We hope everyone had a great holiday season and a good start to 2025! Goals for this year: -Build out our dyno cell & have a functional dynamometer to test our engines with -Finish some of those half-finished projects that you all have been waiting to see... -Post MORE content and BETTER content -Keep learning, trying new things, and sharing our work with you all! Thanks everyone for the support!
I repair CNC for a living. Please check the alignment of your tailstock. Firstly, the taper that you saw in the part is most likely due to it not being perfectly inline with the spindle. Second, after the crash, the tailstock will defiantly not be in alignment with the spindle. It will need to be checked for centerline of the spindle as well as straightness with the Z axis. Straightness is checked first and is done with the ram extended running an indicator along the ram with the cross slide. Once straight, an indicator in the spindle can be used to indicate inside of the ram taper to make centerline. Also if you face the part, then spot drill and deep drill to depth before pulling your material out you will have much better results. This allows the part to be much better supported by the chuck while doing these operations. Having the material sticking out so far and being slightly bent will allow for it to whip slightly. Whip can cause a drill to cut too big, like you saw. I understand that you were trying to keep everything concentric. This advice is not meant for every case, just more info for you. Keep up the good work! Hope this helps.
For what it's worth, as you noted, you're on a learning curve. Having said that, remember the word "fail" is also an acronym for "First Attempt In Learning". Thanks for taking us along.
I was a mechanic for over 50 years , rebuilding engines , fabricating and making all,kinds of contraptions for forklifts, bobcats and industrial machines, 35 of those years as a road mechanic ! I think you and your dad are fantastic on all the machines and do such a meticulous job on your rebuilds , love your videos and work . 👍🏻👍🏻
As a moldmaker years ago, I would have chucked the stock with about 1" extending. Face-off and center drill. I would recommend increasing to a #6 center drill and give yourself ~1/2 dia. chamfer allowing more contact with the live center. Next, I would rough drill the hole to 23/64" to depth +1/4". Next, ream the 3/8" diameter hole. Remember reaming is best at ~1/3 the drill speed. I always had a set of +.001" and -.001" reamers, and would ream accordingly to the fit of ejector pins. Now, extend your stock to length. Turn the OD. Keep in mind you have great experience on manual machines, you just need to apply this knowledge while running CNC equipment. Its like learning a new language, but experiences will prevail. Keep up the great content!
If you are doing precision measuring, use the proper measuring tools. For what I used to do, 0.001" was a wide-open tolerance and that was on huge parts.
25 year veteran of CNC lathe programming and operating here. 1st. Don’t let the mistakes discourage you. Just learn from them. 2nd. On the crash into the live center. The main reason for crashes is usually due to a bad touch-off/offset. And I don’t care if I’ve ran a program a 100 times in the past. Every time I go back to it. That first initial approach, have the machine in “single block” and the feed rate turned down. Watch the distance to go on your screen. If it’s got a lot to go, but you’re already close to part. Something’s wrong. And you’ve just avoided a crash.
Kudos to you for showing all the bugger ups. As others have said, chuck the material with minimum stickout, face and centre 🇬🇧 , then carry out any drilling and reaming of holes, ensuring you have enough countersink for supporting the live centre. Only then pull the stock out of the chuck the minimum amount to allow the rest of the machining. Clearance is clearance as they say.
Okay some points: For what you were attempting I would not use mild steel. Go online to McMaster Carr or one of the other online metal suppliers and look for 1144 stress proof steel. The mild steel you were using is often full of internal stresses and it's not the best material for machine ability. The stress proof machines like butter and is 3x's stronger than the mild steel. Don't use a center drill in the lathe, unless you are making a hole for a lathe center. If you are just drilling a hole, use a drill with a 135* split point for your start. It will find center better and track better from jump. What I like to do if I am drilling a deep hole, is let's say I need to drill a .500(1/2) diameter. I will drill to .4375 (7/16), about one inch deep, then switch to a boring bar and skim the the hole out to .500. Then I will switch to my 1/2 drill. The initial bored hole will act as a guide to guide the drill straight and true as the hole is drilled through. The type of drill matters, a normal jobber drill will work, but not as good as an aircraft type drill. They have a split point and are held to better diameter and straightness tolerances than a jobber drill. Peck cycle: I would peck at .010-.025 peck and retract for clearing every 5-10 pecks initially then maybe drop that down to retract every 3-5 pecks as the hole gets deeper. On a part that length I would drill from both sides using the same methods. Reaming: so we got this 1/2 hole, now we need to ream it to .5312(17/32) bore the first inch of the hole to maybe .542, then switch to your reamer. My go to reamer is a right hand cut, left hand spiral flute reamer, also known as a "gun" reamer because it pushes the cuttings ahead of the ream, instead of packing them in the flutes. Turning: I don't know what insert you were using, but it didn't sound happy. For light turning in decent material, I prefer either a CCMT or CCGT insert style. They are available in a wide variety of chip breakers and carbide specs and quality inserts are worth the money. Iscar and Sandvik are my favorites. You really need to have the insert matched to the job and defer to the insert mfgs specs for speeds and feeds and not those from the Lathe mfg. Start conservative on speeds and feeds and if things are looking right, you can then experiment by increasing as needed.OD turning, you should only hear chips hitting the window, not any rumbling/grating/grinding noises when turning. If you're hearing that, something is wrong and it's not going to get better, stop and figure it out.
Great points, I'd like to add my 2 cents worth - the OD of the stock need to be truly round, especially if moving out later to turn OD to ensure precise concentricity. I would have chucked up in a collet (only because I have them) Also, cheap live centres are just that, however in this case its probably good that you didn't have a top of the range centre in there. Cheers
My recommendations for drilling deep holes on the lathe, that run concentric to the OD: - center drills with the 60° flutes are for live centers, not for centerdrilling a hole, use a proper center drill with about 2° more tip angle than the twist drill you are gonne use (2° more so the twist drill allways starts to cut in the middle first, these are easy avaible for common tip angles)) - solid carbide twist drills with an 140° tip angle will wander off much less - solid carbide reamers will straighten out most of your curved holes - gun drills work best, but you need high pressure through coolant for them - if you want to machine parts in multiple set ups, get yourself a self centering 4 jaw cuck and a stack off soft jaws (an cheap 6 jaw chuck with a "set true" back plate will also do) - don't underestimate stresses in material, especialy in hot rolled steel Greetings from Germany Brian
I’m no expert in machining but I would drill the id with minimal stick out from the lathe chuck. Then use the live centre to machine the od. This would give you a better chance of having the od and id being concentric.
Love the honesty Nick. It is what makes the channel authentic. Keep learning mate. My suggestion when drilling the bar after turning to diameter is to have the minimum possible protruding from the chuck when doing the pilot hole and when drilling to size. That should reduce drill wander assuming your chuck is a good quality item and the headstock spindle is properly centred during manufacture.
Thanks for the video. I have over 40 years machining and I was going to offer some input on machining in general and CNC but I see in the comments you have enough to swallow. Keep on smiling.
One way I've found to get a straight hole with a drill bit is to start with a short stubby drill bit and feed slow. Pull the drill out often to get rid of the chips. Go to the end of the flutes with the short bit, then switch to your long bit. The hole you drilled with the short bit will help guide the long bit from wondering. But the key is to pull the bit out often because chip build-up will cause the bit to wonder and bore oversize. A set of stubby drill bits is the most handy thing you can buy!
Interesting, I am not a machinist of any kind but I have been watching a lot of Keith Rucker and Quinn Dunki and the first thing I thought watching you was to center drill with the stock as close to the chuck as possible which wiser heads than mine have pointed out. Quinn talks a lot about the problems of drilling accurate holes with twist drills as well. Good luck guys, I know you've got this.
I believe I would have started with a better piece of material. I would have also center drilled with little or no hang out. But the bottom line is I totally respect your thirst for trying to improve any process and sometimes things just do not go as planned. But you just gained a butt load of experience and that will pay huge dividends in the future. That is exactly the way I operate with continued strides for improvement.
Material was my first thought. Get a “free machining” steel, such as 12L14. Also, a parabolic drills and split points are good for deep holes.Peck cycle hood. Might have to drill smaller and follow with a reamer.
I could make it on a manual lathe but I never learned the CNC. I think that one-off parts are sometimes good candidates for old school. But I can see your a quick learner and will master it.
Nicolas, as someone who also learnt how to use a lathe (and CNC) at university (almost 40yrs ago!) you soon learn that round bar isn't actually round! I loved this video because it is clear that you are a good student and learn quickly. I would also suggest doing a drawing and a machining procedure to ensure you get the logic correct. So if concentricity is important then ensure that the bar is trued at the holding end before turning it around for centering. Well, you know that now and of course you know about not weakening the part before sticking it in the press. Oh well! Thank you, very good video that other folk can learn from.
And as far as chatter, just as you learned on the Serdi, speeds and feeds are a matter of using your eyes and ears to dial back from "recommended speeds/feeds.
We learn more from the fails then when everything goes without issue. The processes and technology is so complicated, there are a multitude of factors - they things go right we never fully understand all or (the critical) factors. When we see others attempt something and it doesn't we work - the lesson is "oh-crap" didn't realize that was a thing. Thanks again for sharing - keep up the good work (and take the cleaning guy out for lunch occasionally....)
for a guy that didn't get a lot of training on it you are doing good, It's better than not trying guy for sure. working on getting the best out of the machining is hard with some of them older motor blocks and heads . Always enjoy learning from you guys on how you try to get the job done right.
Tried and true. Run your ID hole first with a center hole. Turn around, indicate opposite side true and center the ID hole. Rig up and run between centers. If you can't blend the OD then make it longer and cut off to the length you need.
Thanks for the video. You folks are doing a great job on this old engine. Nice work. Great video too watch and learn from. Many thanks. The Iowa farm boy. Steve. 😊👍🇺🇸🇺🇸
I'm in the process of disassembling a 239 flatty. After several months of on and off work, I finally got the last three of the pistons out yesterday only for a small crack to catch my eye, similar to what this Mercury block had. I am hoping that the shop I plan on using for the machine work can do a similar repair on my engine to what you demonstrated in the last video on this engine. Nice to see you guys working on these old flatheads.
Great work. Always face, centre and drill as close to the chuck as you can before pulling the work piece out to it's extension. However you are on a learning curve and you are working around problems well. Keep up the good work and great content.
my observation.. the chucked end of stock needs to be first prepared as everything else is relative to it. I.E. make the chucked end perfectly round and smooth as a FIRST step.
Very nice explanation, and I think what you were hoping to do was a very good thing. Try it again, when you have a bit more time. If you're working with cold rolled steel, there's always some stress built into the piece, so if you need precision, as in this case, consider annealing the work before you start. Or buy some stock that's already been stress relieved. As for keeping a long center bore straight & centered, sometimes it's best to drill, bore, & ream the center hole first, all the way thru, then finish the OD with the work resting on centers at each end, with a lathe dog driving the work. Use a very large center drill to give plenty of taper for the starting end, so the bore doesn't remove all of it. The far end taper will be harder to keep centered on the bore. I don't think lube would have helped on that press fit. The chip clearance slot just removed too much strength. You need less interference or just mill the slot last. Or don't mill the slot all the way thru.
I would suggest drilling the centering hole (and perhaps even the center drilled hole) while the part is in its original position (i.e., close the the chuck), THEN extending the part out to be able to machine the outer diameter. This method has its own challenges, but the part being much more rigid while drilling the centering hole helps to ensure the hole position.
We used to make similar tools to that. We'd make them out of 1045. First, we'd turn them and leave them 0.003" big. Then we'd wrap them in foil and heat treat them. Finally we'd use a centerless grinder to take them down to finish size and surface. They'd come out with a 65+ Rockwell hardness, a 3 to 5 surface finish and were + or - 0.0002" For the center holes, we made separate bronze bushings with a 0.003" crush fit. Once they were installed, we'd hone them to finish size. I think the hardness is important so the tool doesn't wear under use. Good luck!
You did a good job! always make sure the stock you're working with in a 3 Jaw self centring chuck is as far in the jaws as you can get. Especially when center drilling, never have you're work piece out side of the chuck. That goes with drilling deep holes. Haas has coding is annoying when it comes to the post processing and its easy to have the tool cut too deep in a canned cycle. P71 call outs usually try to devide your cuts into equal steeps until finished depth is hit. And if you dont have your chip load a feed per tooth selected in your tool chain via fusion 360. It'll take deeper cuts as it gets closer to its finishing pass. Thats probably why you noticed huge tool load and had to stop the machining process and restart, assuming you checked wear comp or canned cycle stepp over.
For drilling deep holes straight, use a special gun drill bit. We fabricated nozzles for our chain-mold extrusion machines inhouse on a CNC lathe. Machining began by turning the outside profile of the nozzle. This was basically a large threaded connection for the extrusion machine that tapered at 30-45 degrees to a slender rod. That slender rod would then be gun drillled to make an injection tube that would extend into the extrusion mold halves. Lengths of those "tubes" were approximately six inches in length with wall thickness of approximately 0.020"-0.030". Finally, a tapered internal transition was machined into the connection end. I did not believe it could be done until we tried it.
You have enough experience using a lathe but the set and options used in a CNC machine is mind boggling ! LOl many people with years of experience have the same problem at times , your doing great !
I have seen the tool you were trying to make. It's not in my Sioux seat grinder but it may be in my kwik way seat grinder deep in storage. Harmonics with the serti. Try a urethane shock absorber bushing on the pilot. You may need to use the wire hose clamp maker to give it enough squeeze on the pilot to dampen any harmonics. Or a cv boot stainless band clamp. You will have to play with the clamp compression.
Hey guys love the channel been a fan a long time. The guys at LAOL gave you a shout out about checking there Caterpillar heads. Would be awesome to see you guys work on some of the old Caterpillar equipment stuff I love the detail you guys go into on the projects you have. Also cool you guys are near each other. Thanks for the videos.
Maybe drill the hole with minimum stick out, chop it off afterwards, make a dead center then run between centers with a lathe dog, that should make the outside concetric with the bore, idk if it would help alot but worth a try
Yeah sometimes the first attempt on making a tool doesn’t quite work out we have all been there. Happened to me this week. Came back fresh the next day refined it a little and it worked perfectly
I love watching you guys work. Not sure if it applies, but I see people tightening the chucks and it is flawless, but when I was entry maintenance we had an old lathe with a really old chuck that was completely worn out, it would take 15 minutes to get it centered by loosening the chuck on the side it needed to go to be centered, then tightening the other side, this would go on untill you could turn it 360 degrees and still have contact with the cuting bit. That's all I got, may not apply, your chuck may just be junk, hope it helps.
Not sure what manufacturer tools you used but here on production machining (in EU) we use a lot of Walter, Seco, Sandvik and Iscar tools. Not gonna go in depth what exact tools from them as this message would be a book long. I guess in States theres a lot of Kennametal tools for machining, we use their products mainly for drilling deep holes (solid carbide drilling inserts for drilling body that can be all the way up to 9 X diameter deep, maybe More than that) But it requires coolant through the drill. For the machining method that you used, could also use G74 for basic od roughing as I think you used G73, and if the material is tool steel you need to keep rpm quite low, otherwise you will end up with broken inserts. Quite good suggestions here already about how to do that part without this much issues, but its learning experience, just make sure everything is in centre and aligned, longer that bar stock is out of the jaws the more things will vibrate and bend, loved the video ❤
when you make a center hole, it is a really good idea to have the end of the martial as close to the 3 claw dom as possible, then the hole will also be more accurate and in the center of the steel
Great, helpful info from lathe operators! Concur with drill geometry and precision. Also, you'll get a more consistent hole with a ream (mentioned by several here too). But for a really nice guide diameter, how do you do it? Right, hone it.
It looks like you were using a Groove and Turn tool for turning the O D. Those tools work great for back turning, where you first plunge to a depth several times in a row and then clean up by traversing. In other words very minimal z-axis pressure. Cnnm tools work great for z-axis pressure due to how much inset and material behind the insert. But any number of tools will work fine. Is the material known? Or something out of the scrap pile? Kinda looks like what happens with case hardened material.
I was starting to go through withdrawls not getting my cleaning crew fix. Personally, i would have started with a piece of 1045 tgp instead of hot/cold roll. Hot/cold doesnt have consistent sectional density which will bite you on precision parts. It looks like there was a lot of runout being that far from the chuck. The more concentric the part runs the less vibration and chatter. Put the center in choked up to the chuck. Youll get it its one of those things you have to mess up to learn. I have a lot of accusize tools, middle of the road cost and quality.
For the hole you might try a smaller Q value. Or if you're using IJK a smaller K value. Under size the hole and then use a reamer. Honestly I have similar problems with drilling small holes so I'm not much help here. On the boring bar you found out how crazy those little insert boxes are 😂. Couldn't tell if your boring bar is carbide. Carbide is all I'll use now. Not sure if your TL is equipped but you could also try M38 to reduce chatter. On your oops. Feed hold, 5% rapid, hit position until it gives you "Distance to go" eyeball whether it's actually that distance for a second. If you're comfortable hit cycle start. But cover feed hold like your life depends on it. ☺️
9:04 NOTE: I am not a machinist. I have however watched hours of work by Abom79, Kieth Rucker, Inheritance machining, HAL in Austrailia, CEE Austrailia, Topper Machine, and likely others. Based on that class, I would try leaving the part chucked deep for the initial facing, center drill, and pilot drill. Use a smaller bit for the pilot, and plan on using a reamer to get an exact dimension for the hole. Once you extend the part, set your carriage so that your tool can barely reach the start point, and bring the tailstock as close as possible to improve rigidity at the live center. Take small cuts - you will have to know your own machine and tooling well enough to properly set speeds & feeds, but there is no shame in taking 10 to 20 thousandths at a time to avoid part flex. Let the part cool before your final pass. Finish your part one thousandth too large, and using emery cloth polish it down to the exact 10th of a 1000th that you are wanting. Let the part cool before your final pass. I am not saying you did or did not do any of those steps - there are lots of ways to skin a cat - but if it were me having those problems, these are the things I would look at first.
My recommendation for concentricity on the lathe is to start the hole with a center drill. The live center mess up is why you need to be right there on the stop button when you start a program. Good luck
Solid channel. You deserve every dime you make off of youtube and affiliates for the time and effort you put in. Give the cleaning guy a little extra too.
Lifter bore coaxial to the guide is not a requirement since the lifters spin I would think. But it is cool to get precision never seen for 70 year old flat head Fords. Can't argue with your results the valve job looks beautiful. As for the CNC, you're on your own pal. 🤣😆
I had three years of metal shop in high school plus I have a old South Bend 9 x 36” lathe so I’m no expert but when I drill a center hole for a live center, I like to have the piece close to the chuck as possible I think sticking it out 7 inches would add some wobble.
I have found i get a straighter more centered hole by drilling a smaller initial hole about a 3/8 to 1/2" deep then use a micro or mini boring bar to bore the hole to size , then drill the 2" deep hole to size.
I have used a single-ended end mill to straighten a hole where boring bar will not fit well. I had quite a drawer full of end mills that would give me an exact size and leave a better finish than a reamer.
The lathe. Looks like you didn’t have a deep enough cut to keep deeper than the radius on the cutting tip. It’s rubbing then and not cutting. And is essentially shoving metal in front of the tip till it builds up and chips the edge in a large mass.
Only thing I’d say is you have too much stick out of material I noticed when center drilling . If your cut is too aggressive you’re gonna get deflection and chatter. Different inserts make a huge difference as well , sometimes it’s trial and error.
I'm not a machinist, but you mentioned knurling the removable valve guide. Could you instead use plasma spray to build up the surface diameter ? I only heard of it in GT-R cylinder walls. Then where could you have it done, and at what cost.
Good content... I would of given the bar stock a roll on flat surface after it was cut from the saw then leaving a bit more out than you had for facing off ...face.. center drill ...drill out I.D. ..chamfer...then bring out and turn O.D. length then cut off....your program may take a secondary letter code on your length turn axis to work with that letter code to control taper ..read your machine manual before doing so...thanks ..🔧🔧👍
Thanks for the heads-up. I often wonder whether an old flattie can be a reliable daily driver capable of 30,000 miles without drama. It would be fun to use an A-V8 as everyday transportation.
I have heard of a conversion kit that replaces the bypass filter with a full flow filter. I suppose that would be the best first place to start. Many new flathead valve kits use modern stainless steel valves from a small block Chevy. Replacement water pumps can be bought which have modern sealed bearings and CAD designed impellers. There are ways to replace the road draft tube with a PCV system. Certain types of replacement piston have a different ring pack that can be ordered with more durable stuff. EGGE and Speedway motors have cast pistons which take 5/64 5/64 3/16 rings, which may last longer than the 3/32 3/32 3/16 3/16 stock type. Forged pistons sometimes let you use modern 1.5mm 1.5mm 3mm rings which are much more durable.
If you want deep concentric holes, you need to start drill, bore to a thou under drill size, then gun drill. But that also requires high pressure coolant, around 1000psi depending on hole size. I drill holes ~16x dia to within .002 tir. if you need better than that, you have to bore.
You might try to bore and ream your center hole first and then turn a piece stock in the chuck to fit the hole with slight larger diameter taper toward the chuck . I would first make sure you had an accurate center drilled hole in the other end of the part for the live center
I don't know if you guys have a manual lathe or not, but that seems like it would be a lot easier on a manual lathe, because you could just sneak up on it until it fits right. Manual lathes are also great to have around for second operations. The only other thing that occurs to me is that you might want to use a reamer for that inside bore, maybe you did and I just couldn't tell because I did watch this on my phone. For what it's worth, manual lathes can be had very cheap, maybe 3,000 would get you one that's plenty good enough.
It's not that I'm arguing, and I certainly understand the uses of a CNC lathe. Some things are just easier on a manual. It's also a lot harder to crash tools on a manual. Easier to take a spring pass too. Easier to polish that last thousandth that you need. A manual lathe will never do what a CNC will do, I get that fully. But a manual lathe is so cheap and so useful and so fast and so handy no CAD/CAM required, just seems more efficient to have both. There were many times when the engineers were still messing around building 3D models and rendering and fixing toolpaths and all kinds of stuff like that, I would get impatient and just make the damn thing. Your channel is awesome, BTW, I watch every minute.
I commented once b4, suggesting reaming drilled holes cuz reams are much stiffer than drills. If bent holes still result, a good ( ridgid) boring bar is the only other solution. "D"
Never messed with those fancy lathes. On a manual lathe I'd drill the center to undersized then ream to final size. Cut the stock off a couple inches longer than necessary and turn the OD between centers with a drive dog and the tail support offset the amount needed for the taper. Unless your lucky enough to have a taper attachment. By turning between centers you're insured concentrically.
You’ve got way more lathe than you need. Manual would have been more than sufficient for shop that wouldn’t use a CNC lathe for production. Could have roughed out the od, rough cut the length. Drill your hole going from stub drill to jobber to extra length drill. Finish your internal diameters then the overall length. Then put your part between centers and turn the od to the finish diameter. Put a piece of material in the chuck and true up a taper. Then put your part in and bring the tail stock up. Put a reasonable amount of torque on the tail stock handle, just enough to keep it from spinning. Good luck. 🍀
Nice job, that’s where I think a manually operated lathe is better, so you control it yourself and measure as you go, just my preference as an amateur anyway.
We hope everyone had a great holiday season and a good start to 2025! Goals for this year:
-Build out our dyno cell & have a functional dynamometer to test our engines with
-Finish some of those half-finished projects that you all have been waiting to see...
-Post MORE content and BETTER content
-Keep learning, trying new things, and sharing our work with you all!
Thanks everyone for the support!
Thank you for being "Support Worthy". Y'alls content is always entertaining, but most importantly, it's massively informative.
Can't wait to see what you have planned for the dyno.
You could slow that lathe down just a little bit
It's a lathe not a Mailing. machine
I enjoy watching all of your videos. You and the cleaning guy do a great job. Its nice that you show all of it, even the mistakes. That keeps it real.
Look up cee Australia
I repair CNC for a living. Please check the alignment of your tailstock. Firstly, the taper that you saw in the part is most likely due to it not being perfectly inline with the spindle. Second, after the crash, the tailstock will defiantly not be in alignment with the spindle. It will need to be checked for centerline of the spindle as well as straightness with the Z axis. Straightness is checked first and is done with the ram extended running an indicator along the ram with the cross slide. Once straight, an indicator in the spindle can be used to indicate inside of the ram taper to make centerline.
Also if you face the part, then spot drill and deep drill to depth before pulling your material out you will have much better results. This allows the part to be much better supported by the chuck while doing these operations. Having the material sticking out so far and being slightly bent will allow for it to whip slightly. Whip can cause a drill to cut too big, like you saw. I understand that you were trying to keep everything concentric. This advice is not meant for every case, just more info for you.
Keep up the good work! Hope this helps.
I'm sorry to say, but chris is right. Don't ask me how I know.
For what it's worth, as you noted, you're on a learning curve. Having said that, remember the word "fail" is also an acronym for "First Attempt In Learning". Thanks for taking us along.
I was a mechanic for over 50 years , rebuilding engines , fabricating and making all,kinds of contraptions for forklifts, bobcats and industrial machines, 35 of those years as a road mechanic ! I think you and your dad are fantastic on all the machines and do such a meticulous job on your rebuilds , love your videos and work . 👍🏻👍🏻
As a moldmaker years ago, I would have chucked the stock with about 1" extending. Face-off and center drill. I would recommend increasing to a #6 center drill and give yourself ~1/2 dia. chamfer allowing more contact with the live center. Next, I would rough drill the hole to 23/64" to depth +1/4". Next, ream the 3/8" diameter hole. Remember reaming is best at ~1/3 the drill speed. I always had a set of +.001" and -.001" reamers, and would ream accordingly to the fit of ejector pins. Now, extend your stock to length. Turn the OD.
Keep in mind you have great experience on manual machines, you just need to apply this knowledge while running CNC equipment. Its like learning a new language, but experiences will prevail.
Keep up the great content!
Precisely, i have no idea why he did not center drill after facing off .
very good, you would make a great teacher
I'm just a hobby machinist, but "that's so much stick out on the drilling operation " was my first thought. Live and learn.
Great advice
If you are doing precision measuring, use the proper measuring tools. For what I used to do, 0.001" was a wide-open tolerance and that was on huge parts.
25 year veteran of CNC lathe programming and operating here.
1st. Don’t let the mistakes discourage you. Just learn from them.
2nd. On the crash into the live center. The main reason for crashes is usually due to a bad touch-off/offset. And I don’t care if I’ve ran a program a 100 times in the past. Every time I go back to it. That first initial approach, have the machine in “single block” and the feed rate turned down. Watch the distance to go on your screen. If it’s got a lot to go, but you’re already close to part. Something’s wrong. And you’ve just avoided a crash.
Thanks for showing your challenges with the lathe. Really appreciated!
I wouldn't have anything to show if I didn't show the challenges hahaha
Hey even @Abom79 didn't pick up CNC machining overnight, and that dude works on lathes almost all the time. Keep it up it's worth learning.
Kudos to you for trying to make the tooling you don't learn unless you try. Failures teach more than successes.
Kudos to you for showing all the bugger ups.
As others have said, chuck the material with minimum stickout, face and centre 🇬🇧 , then carry out any drilling and reaming of holes, ensuring you have enough countersink for supporting the live centre. Only then pull the stock out of the chuck the minimum amount to allow the rest of the machining. Clearance is clearance as they say.
Both you and your dad put forth the extra effort to make sure the end result in the end is better than the original specs. Truly a vanishing breed!!
Engine looks great.
Always center drill with your material as close to the chuck as possible, and drill before you extend material out of the chuck.
Okay some points:
For what you were attempting I would not use mild steel. Go online to McMaster Carr or one of the other online metal suppliers and look for 1144 stress proof steel. The mild steel you were using is often full of internal stresses and it's not the best material for machine ability. The stress proof machines like butter and is 3x's stronger than the mild steel.
Don't use a center drill in the lathe, unless you are making a hole for a lathe center. If you are just drilling a hole, use a drill with a 135* split point for your start. It will find center better and track better from jump.
What I like to do if I am drilling a deep hole, is let's say I need to drill a .500(1/2) diameter. I will drill to .4375 (7/16), about one inch deep, then switch to a boring bar and skim the the hole out to .500. Then I will switch to my 1/2 drill. The initial bored hole will act as a guide to guide the drill straight and true as the hole is drilled through. The type of drill matters, a normal jobber drill will work, but not as good as an aircraft type drill. They have a split point and are held to better diameter and straightness tolerances than a jobber drill. Peck cycle: I would peck at .010-.025 peck and retract for clearing every 5-10 pecks initially then maybe drop that down to retract every 3-5 pecks as the hole gets deeper. On a part that length I would drill from both sides using the same methods.
Reaming: so we got this 1/2 hole, now we need to ream it to .5312(17/32) bore the first inch of the hole to maybe .542, then switch to your reamer. My go to reamer is a right hand cut, left hand spiral flute reamer, also known as a "gun" reamer because it pushes the cuttings ahead of the ream, instead of packing them in the flutes.
Turning: I don't know what insert you were using, but it didn't sound happy. For light turning in decent material, I prefer either a CCMT or CCGT insert style. They are available in a wide variety of chip breakers and carbide specs and quality inserts are worth the money. Iscar and Sandvik are my favorites. You really need to have the insert matched to the job and defer to the insert mfgs specs for speeds and feeds and not those from the Lathe mfg. Start conservative on speeds and feeds and if things are looking right, you can then experiment by increasing as needed.OD turning, you should only hear chips hitting the window, not any rumbling/grating/grinding noises when turning. If you're hearing that, something is wrong and it's not going to get better, stop and figure it out.
Great points, I'd like to add my 2 cents worth - the OD of the stock need to be truly round, especially if moving out later to turn OD to ensure precise concentricity. I would have chucked up in a collet (only because I have them) Also, cheap live centres are just that, however in this case its probably good that you didn't have a top of the range centre in there. Cheers
use 4140 ph...
Excelente comentário.
Foi cirúrgico.
Obrigado por isso.
Abraços do Brasil 🇧🇷
Its nice to see your honesty and show all!
Your ingenuity when it comes to finding simple solutions for complex problems never fails to impress me. Real engineers at work!
My recommendations for drilling deep holes on the lathe, that run concentric to the OD:
- center drills with the 60° flutes are for live centers, not for centerdrilling a hole, use a proper center drill with about 2° more tip angle than the twist drill you are gonne use
(2° more so the twist drill allways starts to cut in the middle first, these are easy avaible for common tip angles))
- solid carbide twist drills with an 140° tip angle will wander off much less
- solid carbide reamers will straighten out most of your curved holes
- gun drills work best, but you need high pressure through coolant for them
- if you want to machine parts in multiple set ups, get yourself a self centering 4 jaw cuck and a stack off soft jaws
(an cheap 6 jaw chuck with a "set true" back plate will also do)
- don't underestimate stresses in material, especialy in hot rolled steel
Greetings from Germany
Brian
I’m no expert in machining but I would drill the id with minimal stick out from the lathe chuck. Then use the live centre to machine the od. This would give you a better chance of having the od and id being concentric.
The rough stock is not true. It's going to run out when he pulls it to cut tbe OD. So that wouldn't work very well
Good job on editing. The shots of valve seats being cut were awesome.
Thanks! Was trying a new format so I am glad you enjoyed!
Love the honesty Nick. It is what makes the channel authentic. Keep learning mate. My suggestion when drilling the bar after turning to diameter is to have the minimum possible protruding from the chuck when doing the pilot hole and when drilling to size. That should reduce drill wander assuming your chuck is a good quality item and the headstock spindle is properly centred during manufacture.
Glad you showed the Boo Boo, and the lesson learned. Takes a great engineer to learn rather than bluff it and blame the ex and or dog. Great work.
Thanks for the video. I have over 40 years machining and I was going to offer some input on machining in general and CNC but I see in the comments you have enough to swallow. Keep on smiling.
One way I've found to get a straight hole with a drill bit is to start with a short stubby drill bit and feed slow. Pull the drill out often to get rid of the chips. Go to the end of the flutes with the short bit, then switch to your long bit. The hole you drilled with the short bit will help guide the long bit from wondering. But the key is to pull the bit out often because chip build-up will cause the bit to wonder and bore oversize. A set of stubby drill bits is the most handy thing you can buy!
why anyone would be critical of you I don't understand. One of my top favorite channels.
Because it’s the internet, and people are weird 😂
Yep, Never go in dry!
Interesting, I am not a machinist of any kind but I have been watching a lot of Keith Rucker and Quinn Dunki and the first thing I thought watching you was to center drill with the stock as close to the chuck as possible which wiser heads than mine have pointed out. Quinn talks a lot about the problems of drilling accurate holes with twist drills as well. Good luck guys, I know you've got this.
I believe I would have started with a better piece of material. I would have also center drilled with little or no hang out. But the bottom line is I totally respect your thirst for trying to improve any process and sometimes things just do not go as planned. But you just gained a butt load of experience and that will pay huge dividends in the future. That is exactly the way I operate with continued strides for improvement.
Part of the problem is that getting good quality material is a challenge for everyone.
Material was my first thought. Get a “free machining” steel, such as 12L14. Also, a parabolic drills and split points are good for deep holes.Peck cycle hood. Might have to drill smaller and follow with a reamer.
I could make it on a manual lathe but I never learned the CNC. I think that one-off parts are sometimes good candidates for old school. But I can see your a quick learner and will master it.
Nicolas, as someone who also learnt how to use a lathe (and CNC) at university (almost 40yrs ago!) you soon learn that round bar isn't actually round! I loved this video because it is clear that you are a good student and learn quickly. I would also suggest doing a drawing and a machining procedure to ensure you get the logic correct. So if concentricity is important then ensure that the bar is trued at the holding end before turning it around for centering. Well, you know that now and of course you know about not weakening the part before sticking it in the press. Oh well! Thank you, very good video that other folk can learn from.
Remember that recommended speed and feeds are Recommendation’s. Your eyes and ears can give you the true speeds and feeds.
And as far as chatter, just as you learned on the Serdi, speeds and feeds are a matter of using your eyes and ears to dial back from "recommended speeds/feeds.
We learn more from the fails then when everything goes without issue. The processes and technology is so complicated, there are a multitude of factors - they things go right we never fully understand all or (the critical) factors. When we see others attempt something and it doesn't we work - the lesson is "oh-crap" didn't realize that was a thing. Thanks again for sharing - keep up the good work (and take the cleaning guy out for lunch occasionally....)
for a guy that didn't get a lot of training on it you are doing good, It's better than not trying guy for sure. working on getting the best out of the machining is hard with some of them older motor blocks and heads . Always enjoy learning from you guys on how you try to get the job done right.
Thanks!
Thank you!!!
Tried and true. Run your ID hole first with a center hole. Turn around, indicate opposite side true and center the ID hole. Rig up and run between centers. If you can't blend the OD then make it longer and cut off to the length you need.
Thanks for the video. You folks are doing a great job on this old engine. Nice work.
Great video too watch and learn from.
Many thanks.
The Iowa farm boy. Steve.
😊👍🇺🇸🇺🇸
I'm in the process of disassembling a 239 flatty. After several months of on and off work, I finally got the last three of the pistons out yesterday only for a small crack to catch my eye, similar to what this Mercury block had. I am hoping that the shop I plan on using for the machine work can do a similar repair on my engine to what you demonstrated in the last video on this engine.
Nice to see you guys working on these old flatheads.
Great work. Always face, centre and drill as close to the chuck as you can before pulling the work piece out to it's extension. However you are on a learning curve and you are working around problems well. Keep up the good work and great content.
Always interesting trying new things, see what does/doesn't work, and learning things along the way.
my observation.. the chucked end of stock needs to be first prepared as everything else is relative to it. I.E. make the chucked end perfectly round and smooth as a FIRST step.
A lot can be learned by watching Curtis at Cutting Edge Engineering. His technics are A!.
My thought exactly
I want his tools.
Very nice explanation, and I think what you were hoping to do was a very good thing. Try it again, when you have a bit more time. If you're working with cold rolled steel, there's always some stress built into the piece, so if you need precision, as in this case, consider annealing the work before you start. Or buy some stock that's already been stress relieved.
As for keeping a long center bore straight & centered, sometimes it's best to drill, bore, & ream the center hole first, all the way thru, then finish the OD with the work resting on centers at each end, with a lathe dog driving the work. Use a very large center drill to give plenty of taper for the starting end, so the bore doesn't remove all of it. The far end taper will be harder to keep centered on the bore.
I don't think lube would have helped on that press fit. The chip clearance slot just removed too much strength. You need less interference or just mill the slot last. Or don't mill the slot all the way thru.
I would suggest drilling the centering hole (and perhaps even the center drilled hole) while the part is in its original position (i.e., close the the chuck), THEN extending the part out to be able to machine the outer diameter. This method has its own challenges, but the part being much more rigid while drilling the centering hole helps to ensure the hole position.
Failure is just learning what not to do next time. Enjoying the videos. Please keep them coming!!!
We used to make similar tools to that. We'd make them out of 1045. First, we'd turn them and leave them 0.003" big. Then we'd wrap them in foil and heat treat them. Finally we'd use a centerless grinder to take them down to finish size and surface. They'd come out with a 65+ Rockwell hardness, a 3 to 5 surface finish and were + or - 0.0002" For the center holes, we made separate bronze bushings with a 0.003" crush fit. Once they were installed, we'd hone them to finish size. I think the hardness is important so the tool doesn't wear under use. Good luck!
You did a good job! always make sure the stock you're working with in a 3 Jaw self centring chuck is as far in the jaws as you can get. Especially when center drilling, never have you're work piece out side of the chuck. That goes with drilling deep holes.
Haas has coding is annoying when it comes to the post processing and its easy to have the tool cut too deep in a canned cycle. P71 call outs usually try to devide your cuts into equal steeps until finished depth is hit. And if you dont have your chip load a feed per tooth selected in your tool chain via fusion 360. It'll take deeper cuts as it gets closer to its finishing pass. Thats probably why you noticed huge tool load and had to stop the machining process and restart, assuming you checked wear comp or canned cycle stepp over.
For drilling deep holes straight, use a special gun drill bit. We fabricated nozzles for our chain-mold extrusion machines inhouse on a CNC lathe. Machining began by turning the outside profile of the nozzle. This was basically a large threaded connection for the extrusion machine that tapered at 30-45 degrees to a slender rod. That slender rod would then be gun drillled to make an injection tube that would extend into the extrusion mold halves. Lengths of those "tubes" were approximately six inches in length with wall thickness of approximately 0.020"-0.030". Finally, a tapered internal transition was machined into the connection end. I did not believe it could be done until we tried it.
You have enough experience using a lathe but the set and options used in a CNC machine is mind boggling ! LOl many people with years of experience have the same problem at times , your doing great !
Getting so close to figuring that out. Keep at it and look at some of the other comments, seems like some good advice from CNC operators.
I have seen the tool you were trying to make. It's not in my Sioux seat grinder but it may be in my kwik way seat grinder deep in storage. Harmonics with the serti. Try a urethane shock absorber bushing on the pilot. You may need to use the wire hose clamp maker to give it enough squeeze on the pilot to dampen any harmonics. Or a cv boot stainless band clamp. You will have to play with the clamp compression.
Hey guys love the channel been a fan a long time. The guys at LAOL gave you a shout out about checking there Caterpillar heads. Would be awesome to see you guys work on some of the old Caterpillar equipment stuff I love the detail you guys go into on the projects you have. Also cool you guys are near each other. Thanks for the videos.
Maybe drill the hole with minimum stick out, chop it off afterwards, make a dead center then run between centers with a lathe dog, that should make the outside concetric with the bore, idk if it would help alot but worth a try
For being self taught on the lathe, I will give you an A+. Any mistakes are just an opportunity to learn. Rock on!
Yeah sometimes the first attempt on making a tool doesn’t quite work out we have all been there. Happened to me this week. Came back fresh the next day refined it a little and it worked perfectly
interesting style video for you guys. I like. it's a nice change of pace and is interesting.
I love watching you guys work.
Not sure if it applies, but I see people tightening the chucks and it is flawless, but when I was entry maintenance we had an old lathe with a really old chuck that was completely worn out, it would take 15 minutes to get it centered by loosening the chuck on the side it needed to go to be centered, then tightening the other side, this would go on untill you could turn it 360 degrees and still have contact with the cuting bit.
That's all I got, may not apply, your chuck may just be junk, hope it helps.
Wonderful video ! Thanks for sharing !
Dude... you've got the tools, education, and talent. Don't over think what you're doing.
Overthinking is my specialty 😂😭
Not sure what manufacturer tools you used but here on production machining (in EU) we use a lot of Walter, Seco, Sandvik and Iscar tools. Not gonna go in depth what exact tools from them as this message would be a book long. I guess in States theres a lot of Kennametal tools for machining, we use their products mainly for drilling deep holes (solid carbide drilling inserts for drilling body that can be all the way up to 9 X diameter deep, maybe More than that) But it requires coolant through the drill.
For the machining method that you used, could also use G74 for basic od roughing as I think you used G73, and if the material is tool steel you need to keep rpm quite low, otherwise you will end up with broken inserts. Quite good suggestions here already about how to do that part without this much issues, but its learning experience, just make sure everything is in centre and aligned, longer that bar stock is out of the jaws the more things will vibrate and bend, loved the video ❤
when you make a center hole, it is a really good idea to have the end of the martial as close to the 3 claw dom as possible, then the hole will also be more accurate and in the center of the steel
Really enjoy the work and the videos. Hopefully you will be drilling the lifter bores in order to hold the lifter when they are being adjusted.
Well ya did better than I ever could have. But you used the same words I would have! Your doing great just keep trying stuff
Titans of cnc have a great video for drilling deep.
Great, helpful info from lathe operators! Concur with drill geometry and precision. Also, you'll get a more consistent hole with a ream (mentioned by several here too).
But for a really nice guide diameter, how do you do it? Right, hone it.
This was a great "learning experience" video.
It looks like you were using a Groove and Turn tool for turning the O D. Those tools work great for back turning, where you first plunge to a depth several times in a row and then clean up by traversing. In other words very minimal z-axis pressure.
Cnnm tools work great for z-axis pressure due to how much inset and material behind the insert. But any number of tools will work fine.
Is the material known? Or something out of the scrap pile? Kinda looks like what happens with case hardened material.
I was starting to go through withdrawls not getting my cleaning crew fix. Personally, i would have started with a piece of 1045 tgp instead of hot/cold roll. Hot/cold doesnt have consistent sectional density which will bite you on precision parts. It looks like there was a lot of runout being that far from the chuck. The more concentric the part runs the less vibration and chatter. Put the center in choked up to the chuck. Youll get it its one of those things you have to mess up to learn. I have a lot of accusize tools, middle of the road cost and quality.
For the hole you might try a smaller Q value. Or if you're using IJK a smaller K value. Under size the hole and then use a reamer. Honestly I have similar problems with drilling small holes so I'm not much help here. On the boring bar you found out how crazy those little insert boxes are 😂. Couldn't tell if your boring bar is carbide. Carbide is all I'll use now. Not sure if your TL is equipped but you could also try M38 to reduce chatter.
On your oops. Feed hold, 5% rapid, hit position until it gives you "Distance to go" eyeball whether it's actually that distance for a second. If you're comfortable hit cycle start. But cover feed hold like your life depends on it. ☺️
So cool, tool making is so much fun
In regards to stock to use, it’s been my experience to use cold rolled steel. Also using a steady rest on the centering tool for cutting.
Thanks for sharing...! Keep up your awesomeness...!
We learn through failures. You'll get it. It helps you are young enough to learn things easier.
I sure enjoy your adventures.
This whole comment section is wholesome, I love it.
9:04 NOTE: I am not a machinist. I have however watched hours of work by Abom79, Kieth Rucker, Inheritance machining, HAL in Austrailia, CEE Austrailia, Topper Machine, and likely others.
Based on that class, I would try leaving the part chucked deep for the initial facing, center drill, and pilot drill. Use a smaller bit for the pilot, and plan on using a reamer to get an exact dimension for the hole.
Once you extend the part, set your carriage so that your tool can barely reach the start point, and bring the tailstock as close as possible to improve rigidity at the live center. Take small cuts - you will have to know your own machine and tooling well enough to properly set speeds & feeds, but there is no shame in taking 10 to 20 thousandths at a time to avoid part flex.
Let the part cool before your final pass. Finish your part one thousandth too large, and using emery cloth polish it down to the exact 10th of a 1000th that you are wanting. Let the part cool before your final pass.
I am not saying you did or did not do any of those steps - there are lots of ways to skin a cat - but if it were me having those problems, these are the things I would look at first.
My recommendation for concentricity on the lathe is to start the hole with a center drill. The live center mess up is why you need to be right there on the stop button when you start a program. Good luck
Lol I literally had my hand on the button 😂
@JAMSIONLINE turn the feedrate way down when you start so it is easier to catch a mistake
Solid channel. You deserve every dime you make off of youtube and affiliates for the time and effort you put in. Give the cleaning guy a little extra too.
Thanks! We plan a quarterly pizza party for the cleaning guy! We might even let him choose the toppings this time!
@@JAMSIONLINE Yeah, pizza party is a little over the top. I was thinking $20 bucks.
Lifter bore coaxial to the guide is not a requirement since the lifters spin I would think. But it is cool to get precision never seen for 70 year old flat head Fords. Can't argue with your results the valve job looks beautiful. As for the CNC, you're on your own pal. 🤣😆
I had three years of metal shop in high school plus I have a old South Bend 9 x 36” lathe so I’m no expert but when I drill a center hole for a live center, I like to have the piece close to the chuck as possible I think sticking it out 7 inches would add some wobble.
passion in motion
Kudos for showing your failures, not easy to do by you will undoubtedly prevail. Very cool old motor!
I thought you had the bar stock too far outside the chuck for drilling or use a roller style steady rest to support it
I have found i get a straighter more centered hole by drilling a smaller initial hole about a 3/8 to 1/2" deep then use a micro or mini boring bar to bore the hole to size , then drill the 2" deep hole to size.
I have used a single-ended end mill to straighten a hole where boring bar will not fit well. I had quite a drawer full of end mills that would give me an exact size and leave a better finish than a reamer.
The lathe. Looks like you didn’t have a deep enough cut to keep deeper than the radius on the cutting tip.
It’s rubbing then and not cutting. And is essentially shoving metal in front of the tip till it builds up and chips the edge in a large mass.
Great content thanks for sharing
I would have done the center drill before you extended it out. Center drill as close to the chuck as you can
Center drill, drill undersize, ream to finish, turn OD between centers.
Only thing I’d say is you have too much stick out of material I noticed when center drilling .
If your cut is too aggressive you’re gonna get deflection and chatter. Different inserts make a huge difference as well , sometimes it’s trial and error.
I really liked this video!
I'm not a machinist, but you mentioned knurling the removable valve guide.
Could you instead use plasma spray to build up the surface diameter ?
I only heard of it in GT-R cylinder walls. Then where could you have it done, and at what cost.
Good content... I would of given the bar stock a roll on flat surface after it was cut from the saw then leaving a bit more out than you had for facing off ...face.. center drill ...drill out I.D. ..chamfer...then bring out and turn O.D. length then cut off....your program may take a secondary letter code on your length turn axis to work with that letter code to control taper ..read your machine manual before doing so...thanks ..🔧🔧👍
Thanks for the heads-up. I often wonder whether an old flattie can be a reliable daily driver capable of 30,000 miles without drama. It would be fun to use an A-V8 as everyday transportation.
I have heard of a conversion kit that replaces the bypass filter with a full flow filter. I suppose that would be the best first place to start. Many new flathead valve kits use modern stainless steel valves from a small block Chevy. Replacement water pumps can be bought which have modern sealed bearings and CAD designed impellers. There are ways to replace the road draft tube with a PCV system. Certain types of replacement piston have a different ring pack that can be ordered with more durable stuff. EGGE and Speedway motors have cast pistons which take 5/64 5/64 3/16 rings, which may last longer than the 3/32 3/32 3/16 3/16 stock type. Forged pistons sometimes let you use modern 1.5mm 1.5mm 3mm rings which are much more durable.
If you want deep concentric holes, you need to start drill, bore to a thou under drill size, then gun drill. But that also requires high pressure coolant, around 1000psi depending on hole size. I drill holes ~16x dia to within .002 tir. if you need better than that, you have to bore.
I always under size the drilled hole and use a reamer to get to the finished diameter.
You might try to bore and ream your center hole first and then turn a piece stock in the chuck to fit the hole with slight larger diameter taper toward the chuck . I would first make sure you had an accurate center drilled hole in the other end of the part for the live center
I don't know if you guys have a manual lathe or not, but that seems like it would be a lot easier on a manual lathe, because you could just sneak up on it until it fits right. Manual lathes are also great to have around for second operations. The only other thing that occurs to me is that you might want to use a reamer for that inside bore, maybe you did and I just couldn't tell because I did watch this on my phone. For what it's worth, manual lathes can be had very cheap, maybe 3,000 would get you one that's plenty good enough.
I guess I don't see it as an argument of CNC vs Manual. You can sneak up on it in a CNC just the same as you sneak up on it manually lol
It's not that I'm arguing, and I certainly understand the uses of a CNC lathe. Some things are just easier on a manual. It's also a lot harder to crash tools on a manual. Easier to take a spring pass too. Easier to polish that last thousandth that you need. A manual lathe will never do what a CNC will do, I get that fully. But a manual lathe is so cheap and so useful and so fast and so handy no CAD/CAM required, just seems more efficient to have both. There were many times when the engineers were still messing around building 3D models and rendering and fixing toolpaths and all kinds of stuff like that, I would get impatient and just make the damn thing.
Your channel is awesome, BTW, I watch every minute.
I commented once b4, suggesting reaming drilled holes cuz reams are much stiffer than drills. If bent holes still result, a good ( ridgid) boring bar is the only other solution. "D"
Never messed with those fancy lathes. On a manual lathe I'd drill the center to undersized then ream to final size. Cut the stock off a couple inches longer than necessary and turn the OD between centers with a drive dog and the tail support offset the amount needed for the taper. Unless your lucky enough to have a taper attachment. By turning between centers you're insured concentrically.
Use a center drill for centers, a spotting drill for drilling. Keep trying, it gets easier.
You’ve got way more lathe than you need. Manual would have been more than sufficient for shop that wouldn’t use a CNC lathe for production.
Could have roughed out the od, rough cut the length. Drill your hole going from stub drill to jobber to extra length drill. Finish your internal diameters then the overall length. Then put your part between centers and turn the od to the finish diameter.
Put a piece of material in the chuck and true up a taper. Then put your part in and bring the tail stock up. Put a reasonable amount of torque on the tail stock handle, just enough to keep it from spinning.
Good luck. 🍀
Nice job, that’s where I think a manually operated lathe is better, so you control it yourself and measure as you go, just my preference as an amateur anyway.
Gun drill and reamer for deep holes , you will prevail ! I chuck the stock with little stick out , center drill, then slide out not rotating the stock
If you need a carb for that I have one that might fit, I believe it was off my dads 34 ford, it was wrapped in a rag and in a box.