Wow these last few vids of youre have made up my mind. Going to finaly pull the plug and pick up a lathe from adendorff! Thank you for all info and looking forward to more!
@timrichards3359 lovely comment! My videos are more for the home workshop with smaller equipment, though.... the training I give for industry is different.
I’ve never had a problem parting off. It’s just a matter of doing it correctly. Get center height correct. A problem is that people don’t get it correct. It needs to be EXACTLY at the center line. Part off at a high enough speed and a decent feed. Too many people think that it should be done at a slow speed, but that’s incorrect. If your tools are rigid enough, using a parting tool, usually carbide, that has a slight angle, with the pointed tip towards the side of importance, is just fine. That’s what I use and it works very well. Since lathes are built differently, not all the compounds have bolts at 180 degrees. Mine has two set screws that come in from the side at a 90 degree angle. It’s very rigid. They push the compound down and back. If you have a small lathe that’s not very rigid, then parting can be a problem if you’re not careful.
By angling your cross slide dovetail you also minimize the play left in the gibs by lengthening the force line between the dovetail front and rear. In my mini lathe the gib material is rather soft and I find I have to frequently readjust the gib screws to minimize play, so this geometry change is very useful. Thank you.
Sir, i fear the problem with often re-adjusting the gib screws of the compound, is not caused by soft gib material, but instead ( !!! ) by the compound itself, opening the dovetail more and more ... ( i have the same problem, i hope i'm in error ... ) In any case i got two more compounds as spare parts !!!
Hello. A good informative video. The person who inspired me in parting off was Joe Pie. Some take away things are:- lock the saddle down, use plenty of coolant/lubricant, reduce spindle speed and reduce tool stick-out. I personally do not power feed but it is down everyday on a CNC mill/turn but those machines are highly rigid. I find the quickest way to square up the parting tool or any tool is to use a 123 block sandwiched between the chuck face and the blade holder. Also for setting the cutting edge height, machine up a dedicated height measuring steel cylinder (approx 40mm dia) with a sharp top edge. I made a non-slip knurled grip plus splashed some colour on it to make it look like a jig tool. In use, it sits on top of the saddle as the reference surface and can be done at any time without removing the job. Undercut the base in the centre to ensure it sits flat. For most work I remove the compound and fit a solid steel block. This is a cast iron cylindrical spacer. Doing this improves rigidity greatly and allows extra hold down bolts to be fitted. I have three instead of the two. Also the tool post can have multiple bolting positions (three in my case). I have seen a polyurethane manufacturer use a blade cutter to part off washers. Cheers
Nice comment... just one thing on the CNC, there auto feed is not consistent. It varies based on the tip speed/material so as you move to the centre the feed changes, as well as the speed.
Hi just another thing I thought of. I purchased a blade type parting off holder for a much bigger lathe. The tang that fitted into the quick change holder was much larger. This allowed me to machine it back to size but rotated the entire tool holder back at about 6 degrees. This provided an automatic top rake angle. This way, only the end of the blade needs to be sharpened. The 'V' top of the blade and the tapered sides of the tool help with chip control and reduced friction. I think that parallel side blades should be avoided if possible. Also it is an opportunity to buy blades with a higher cobalt content. Cheers.@@Lukers_tinkering
@@Lukers_tinkering Thanks! That's extremely thoughtful of you. I saw your note about a rear mount parting tool; did you mean the limiting factor was the physical space? I have a Sherline mini lathe I've bulked up, almost doubled the throw capacity & powered w/ a DC treadmill motor. I can turn SS & hard metals ss long as I don't get carried w/ DOC. I converted it to an ER32 & mount the 100 mm chucks I have directly on the ER chuck threads. Pre mods, SS was a chatter nightmare; even mild steel could give fits, at times. Parting was a disaster. I designed & made a rear approach, upside down cutter parting tool which uses carbide tipped blades I get from old carbide circular saw blades. I was a carpenter for nearly 40 yrs, & still have a pile of blades because I have a resharpener & do carpentry on my house & shop. I'm 70, BTW. Can get a dozen parting blades from a 7.25" (~180mm) saw blade. The tool works great. By reversing the opposing forces everything is more rigid. I got the info from a YT vid. GeoD
Rear mounting the parting tool does improve the forces at the tool but not all lathes can handle the reversed spindle rotation. Generally, eastern block lathe cross slides are not designed for that type of loading and the thickness wont accommodate studs safely. As a general rule if the cross slide has t-slots then it will be fine. Your setup sounds perfect. Chatter with parting is when the spindle speed is too high and the feed is too low, but some of the smaller machines can't handle the required forces to dampen the chatter. Then the only option is to go for a thinner parting off tool or improve lathe rigidity, which is what you did... so hats of to solving a problem that many people never solve... Thanks for watching my video!@@georgedennison3338.
@@Lukers_tinkering Thanks... One of my favorite pastimes is making equipment of obsolete/old equipment or parts I scavenge. Partly to keep stuff out of the trash stream, partly for economics, (been disabled from brain injury for 20+ yrs & on fixed income), & partly, it's good for my brain. I don't run my lathe backwards when using the parting tool, I reverse the blade, instead; that was the tip I picked up from the YT vid. The Sherline does have T-slots, but they're tiny; the bolt is a 10-32, (~5mm). The last thing I need to take on is making some bronze/brass gibs. Sherline uses a plastic composite which, even when so tight the cross barely will move, there is flex. The entire project building this, my 1st lathe, from parts & pieces has been a great learning experience & has solidly reinforced the necessity of rigidlty & mass! I'm about to take on a larger lathe 'Frankenstein' project in which I'll fab a skeletal frame connecting the moving parts, then encase it all in epoxy granite. You're in South Africa, right? I suspect you get machine tools of European decent, do they tend to be from certain countries or is there a variety? GeoD
@georgedennison3338 it varies, I've seen machines from all corners here. These training videos are specifically for one of my tool suppliers here in sa. I also prefer making things from scrap. If you dig around my videos, there's casting from scrap and even making name plates using everyday items...
Thank you for the video, interesting perspective. The trick to parting off is to do it upside down. This way the chips exit the bottom. I have parted off 60mm PH17-4 stainless with a 1.5mm blade using auto feed and lubricant. If your lathe doesn't spin backwards then make holder for the back side of the chuck, I'm fortunate to be able to reverse my lathe. I do most of my cutting at ~300 rpms with a fine auto carriage movement. The other thing is your holder, every time you change the distance from the tool holder you have to reset your tool. I use a blade with an insert that always has the tool at the correct height for most of my work. Also, the problem with the holder you made is that the cut off tool is to far from the Aloris so you're adding flexibility, you want the blade as close to the holder as possible. I even took the extra time to make my own blade holder for the Aloris to fix this problem. I used a Chinese hold to do this as Aloris holders are hardened and the Chinese ones aren't. Hope this helps.
Thanks for your comment. Not all lathes can be reversed for parting, especially the Chinese v-bed types. The forces on the carrage will result in jams. I would also be a little apprehensive of not seeing what's going on in the slot, as you can't take corrective action if needs be. The parting forces on a 1-1.5mm blade are small for a medium sized lathe like mine so I don't worry about the overhang, never had a problem with that blade. Cutting a martensitic stainless like you mentioned is possible with that blade but that's probably pushing things a little. If you jam with auto feed when parting you would likely damage the leadscrew key or slot, which is why I prefer hand feeding. Trying that with austenitic stainless or mild steel will probably result in a tool break. My advice is always.... if it works for you then its perfect! Thanks for watching...
@@Lukers_tinkering Thanks Luker. I misspoke, I run stainless at 100 rpms and the slowest feed rate. What happens with the tool post being upside down is that if the blade jams the whole tool post is pushed up out of the cut as opposed to being pushed down which Aloris holders are designed not to do by the height setting nut but they do push up which did happened to me when I tested my theory. My lathe is an Austrian Maximat Super II which is quite a good lathe and the cross slide has a slip ring on it so the lead screw never has the chance of damage. There are also different shafts for thread cutting and bed travel. ( the thread cutter lead screw has aluminum shear pins to keep the system from self destruction.) Two shafts are a much better design as you don't wear your thread cutting lead screw running bed travel. Yes, the only way, if you can't reverse the headstock, is to mount the cutoff tool on the backside of the cross slide, Sherline cutoff tools work this way, by the way. If anyone wants the parts here's the Shars blade I use: 404-0389 Again, the benefit is that you can extend it only the amount you need for a particular job without having to reset the center height but you do have to either make or mod a Chinese AXA holder or use the Shars blade holder for the Aloris, part number: 404-0462 (ebay: Shars 14 PC Set 1/2" Shank Self-Lock Cut-Off Tool +10pcs Inserts) $40. I made my own to keep the extension from the holder to a minimum.
Part upside down so your chips can fly all over the place. Never heard of such a thing. I part with normal rotation. I can assure you that HSS is the problem. Get a carbide insert parting tool and make parting a pleasure. Forge On!!!
@@jmbstudio6873 With the blade upside down the chips fall out the bottom of the cut, there are actually FEWER chips flying around! That's exactly why I cited stainless - it is problematic when cutting off. So if a blade upside down can cut 40mm diameter SS then cutting something like 12L14 is a breeze - get it now?
Not all lathes can handle a carbide parting tip. The added speed and lower feed rate tends to cause chatter with the less stiff hobby machines. Perfect for industry.@@jmbstudio6873
The grinding wheel you show in your video is designed for face and side grinding. A regular flat wheel is not made for grinding on the side. They have been known to shatter. Just a word of warning to those that are not aware of that fact. Just google Can I grind on the side of a grinding wheel.
Its common practice to grind using the side of grinding wheels. Tool room textbooks specify this method for sharpening drill bits. That wheel was actually surplus stock for a surface grinder. That whole tool and cutter grinder setup is home made. The colour of the grinding wheel and applied pressure is probably more important, but that's a topic for another video I think!
One of those tools costs more than most of my cutting tools combined... I've managed to design and scratch build a number of highly complex live steam engines with humble tooling. It's more important for me to collect skills and knowledge than expensive tooling...
Not all lathes can handle a carbide parting tip. The added speed and lower feed rate tends to cause chatter with the less stiff hobby machines. Perfect for industry
My Grizzly G0752 handles it just fine. It is far from an industrial machine. It was rough before I pulled the entire machine apart and put it together correctly. I also may have added several mods to eliminate deflection. Forge On!!! Shars Tools has a great one for a QCTP. I can part 2 inch solid round no problem. The only time it vibrates is when I cut too slow. Faster feed rates work better for me.
Wow these last few vids of youre have made up my mind. Going to finaly pull the plug and pick up a lathe from adendorff! Thank you for all info and looking forward to more!
Picked up the same model as yours today :) thanks for all the info.
Best video for my apprentice to watch
@timrichards3359 lovely comment! My videos are more for the home workshop with smaller equipment, though.... the training I give for industry is different.
Stunning video with a ton of very practical tips and tricks👍😁
I’ve never had a problem parting off. It’s just a matter of doing it correctly. Get center height correct. A problem is that people don’t get it correct. It needs to be EXACTLY at the center line. Part off at a high enough speed and a decent feed. Too many people think that it should be done at a slow speed, but that’s incorrect. If your tools are rigid enough, using a parting tool, usually carbide, that has a slight angle, with the pointed tip towards the side of importance, is just fine. That’s what I use and it works very well. Since lathes are built differently, not all the compounds have bolts at 180 degrees. Mine has two set screws that come in from the side at a 90 degree angle. It’s very rigid. They push the compound down and back. If you have a small lathe that’s not very rigid, then parting can be a problem if you’re not careful.
Chad you are not a sheep you dare to be different what an amazing finish you achieved on the ford under the circumstances have a good day
Thank you for your interesting video regarding parting off also well explained .
By angling your cross slide dovetail you also minimize the play left in the gibs by lengthening the force line between the dovetail front and rear. In my mini lathe the gib material is rather soft and I find I have to frequently readjust the gib screws to minimize play, so this geometry change is very useful. Thank you.
Sir, i fear the problem with often re-adjusting the gib screws of the compound, is not caused by soft gib material, but instead ( !!! ) by the compound itself, opening the dovetail more and more ... ( i have the same problem, i hope i'm in error ... )
In any case i got two more compounds as spare parts !!!
Hello. A good informative video. The person who inspired me in parting off was Joe Pie. Some take away things are:- lock the saddle down, use plenty of coolant/lubricant, reduce spindle speed and reduce tool stick-out. I personally do not power feed but it is down everyday on a CNC mill/turn but those machines are highly rigid. I find the quickest way to square up the parting tool or any tool is to use a 123 block sandwiched between the chuck face and the blade holder. Also for setting the cutting edge height, machine up a dedicated height measuring steel cylinder (approx 40mm dia) with a sharp top edge. I made a non-slip knurled grip plus splashed some colour on it to make it look like a jig tool. In use, it sits on top of the saddle as the reference surface and can be done at any time without removing the job. Undercut the base in the centre to ensure it sits flat. For most work I remove the compound and fit a solid steel block. This is a cast iron cylindrical spacer. Doing this improves rigidity greatly and allows extra hold down bolts to be fitted. I have three instead of the two. Also the tool post can have multiple bolting positions (three in my case). I have seen a polyurethane manufacturer use a blade cutter to part off washers. Cheers
Nice comment... just one thing on the CNC, there auto feed is not consistent. It varies based on the tip speed/material so as you move to the centre the feed changes, as well as the speed.
Hi just another thing I thought of. I purchased a blade type parting off holder for a much bigger lathe. The tang that fitted into the quick change holder was much larger. This allowed me to machine it back to size but rotated the entire tool holder back at about 6 degrees. This provided an automatic top rake angle. This way, only the end of the blade needs to be sharpened. The 'V' top of the blade and the tapered sides of the tool help with chip control and reduced friction. I think that parallel side blades should be avoided if possible. Also it is an opportunity to buy blades with a higher cobalt content.
Cheers.@@Lukers_tinkering
Excellent video showing practical solutions cheers
Great video, Thank You for posting.
Nice tips. I liked the razor technique
Great idea w/ the Stanley blade, going to make one...
Thanks
Thanks George, I've added a little more information on the Stanley tool in the description for you...
@@Lukers_tinkering Thanks! That's extremely thoughtful of you.
I saw your note about a rear mount parting tool; did you mean the limiting factor was the physical space?
I have a Sherline mini lathe I've bulked up, almost doubled the throw capacity & powered w/ a DC treadmill motor.
I can turn SS & hard metals ss long as I don't get carried w/ DOC.
I converted it to an ER32 & mount the 100 mm chucks I have directly on the ER chuck threads.
Pre mods, SS was a chatter nightmare; even mild steel could give fits, at times.
Parting was a disaster.
I designed & made a rear approach, upside down cutter parting tool which uses carbide tipped blades I get from old carbide circular saw blades. I was a carpenter for nearly 40 yrs, & still have a pile of blades because I have a resharpener & do carpentry on my house & shop. I'm 70, BTW.
Can get a dozen parting blades from a 7.25" (~180mm) saw blade.
The tool works great. By reversing the opposing forces everything is more rigid. I got the info from a YT vid.
GeoD
Rear mounting the parting tool does improve the forces at the tool but not all lathes can handle the reversed spindle rotation. Generally, eastern block lathe cross slides are not designed for that type of loading and the thickness wont accommodate studs safely. As a general rule if the cross slide has t-slots then it will be fine. Your setup sounds perfect. Chatter with parting is when the spindle speed is too high and the feed is too low, but some of the smaller machines can't handle the required forces to dampen the chatter. Then the only option is to go for a thinner parting off tool or improve lathe rigidity, which is what you did... so hats of to solving a problem that many people never solve... Thanks for watching my video!@@georgedennison3338.
@@Lukers_tinkering Thanks... One of my favorite pastimes is making equipment of obsolete/old equipment or parts I scavenge. Partly to keep stuff out of the trash stream, partly for economics, (been disabled from brain injury for 20+ yrs & on fixed income), & partly, it's good for my brain.
I don't run my lathe backwards when using the parting tool, I reverse the blade, instead; that was the tip I picked up from the YT vid.
The Sherline does have T-slots, but they're tiny; the bolt is a 10-32, (~5mm). The last thing I need to take on is making some bronze/brass gibs. Sherline uses a plastic composite which, even when so tight the cross barely will move, there is flex.
The entire project building this, my 1st lathe, from parts & pieces has been a great learning experience & has solidly reinforced the necessity of rigidlty & mass!
I'm about to take on a larger lathe 'Frankenstein' project in which I'll fab a skeletal frame connecting the moving parts, then encase it all in epoxy granite.
You're in South Africa, right? I suspect you get machine tools of European decent, do they tend to be from certain countries or is there a variety?
GeoD
@georgedennison3338 it varies, I've seen machines from all corners here. These training videos are specifically for one of my tool suppliers here in sa. I also prefer making things from scrap. If you dig around my videos, there's casting from scrap and even making name plates using everyday items...
Thank you for the video, interesting perspective.
The trick to parting off is to do it upside down. This way the chips exit the bottom. I have parted off 60mm PH17-4 stainless with a 1.5mm blade using auto feed and lubricant. If your lathe doesn't spin backwards then make holder for the back side of the chuck, I'm fortunate to be able to reverse my lathe. I do most of my cutting at ~300 rpms with a fine auto carriage movement.
The other thing is your holder, every time you change the distance from the tool holder you have to reset your tool. I use a blade with an insert that always has the tool at the correct height for most of my work.
Also, the problem with the holder you made is that the cut off tool is to far from the Aloris so you're adding flexibility, you want the blade as close to the holder as possible. I even took the extra time to make my own blade holder for the Aloris to fix this problem. I used a Chinese hold to do this as Aloris holders are hardened and the Chinese ones aren't.
Hope this helps.
Thanks for your comment. Not all lathes can be reversed for parting, especially the Chinese v-bed types. The forces on the carrage will result in jams. I would also be a little apprehensive of not seeing what's going on in the slot, as you can't take corrective action if needs be. The parting forces on a 1-1.5mm blade are small for a medium sized lathe like mine so I don't worry about the overhang, never had a problem with that blade. Cutting a martensitic stainless like you mentioned is possible with that blade but that's probably pushing things a little. If you jam with auto feed when parting you would likely damage the leadscrew key or slot, which is why I prefer hand feeding. Trying that with austenitic stainless or mild steel will probably result in a tool break. My advice is always.... if it works for you then its perfect! Thanks for watching...
@@Lukers_tinkering Thanks Luker.
I misspoke, I run stainless at 100 rpms and the slowest feed rate. What happens with the tool post being upside down is that if the blade jams the whole tool post is pushed up out of the cut as opposed to being pushed down which Aloris holders are designed not to do by the height setting nut but they do push up which did happened to me when I tested my theory.
My lathe is an Austrian Maximat Super II which is quite a good lathe and the cross slide has a slip ring on it so the lead screw never has the chance of damage. There are also different shafts for thread cutting and bed travel. ( the thread cutter lead screw has aluminum shear pins to keep the system from self destruction.) Two shafts are a much better design as you don't wear your thread cutting lead screw running bed travel.
Yes, the only way, if you can't reverse the headstock, is to mount the cutoff tool on the backside of the cross slide, Sherline cutoff tools work this way, by the way.
If anyone wants the parts here's the Shars blade I use:
404-0389
Again, the benefit is that you can extend it only the amount you need for a particular job without having to reset the center height but you do have to either make or mod a Chinese AXA holder or use the Shars blade holder for the Aloris, part number: 404-0462 (ebay: Shars 14 PC Set 1/2" Shank Self-Lock Cut-Off Tool +10pcs Inserts) $40. I made my own to keep the extension from the holder to a minimum.
Part upside down so your chips can fly all over the place. Never heard of such a thing. I part with normal rotation. I can assure you that HSS is the problem. Get a carbide insert parting tool and make parting a pleasure.
Forge On!!!
@@jmbstudio6873 With the blade upside down the chips fall out the bottom of the cut, there are actually FEWER chips flying around!
That's exactly why I cited stainless - it is problematic when cutting off. So if a blade upside down can cut 40mm diameter SS then cutting something like 12L14 is a breeze - get it now?
Not all lathes can handle a carbide parting tip. The added speed and lower feed rate tends to cause chatter with the less stiff hobby machines. Perfect for industry.@@jmbstudio6873
Good info to know. Thanks.
The grinding wheel you show in your video is designed for face and side grinding. A regular flat wheel is not made for grinding on the side. They have been known to shatter. Just a word of warning to those that are not aware of that fact. Just google Can I grind on the side of a grinding wheel.
Its common practice to grind using the side of grinding wheels. Tool room textbooks specify this method for sharpening drill bits. That wheel was actually surplus stock for a surface grinder. That whole tool and cutter grinder setup is home made. The colour of the grinding wheel and applied pressure is probably more important, but that's a topic for another video I think!
👍👍
For Tool height, measure once to the machinebed.. write that down, stick it to the wall!
What's an oring?
👍🏻
If I only knew this before, while parting off me toolpost broke off at the base (cast irion).
If I saw this only a few months earlyer. My toolpost broke off when cutting off......
Tool sharpening one degree positive od listen to chatter.
Get an Iscar parting tool and add 10years to your life.
One of those tools costs more than most of my cutting tools combined... I've managed to design and scratch build a number of highly complex live steam engines with humble tooling. It's more important for me to collect skills and knowledge than expensive tooling...
HSS parting tools are junk. Get a carbide insert parting tool and enjoy the parting operation.
Forge On!!!
Not all lathes can handle a carbide parting tip. The added speed and lower feed rate tends to cause chatter with the less stiff hobby machines. Perfect for industry
My Grizzly G0752 handles it just fine. It is far from an industrial machine. It was rough before I pulled the entire machine apart and put it together correctly. I also may have added several mods to eliminate deflection.
Forge On!!! Shars Tools has a great one for a QCTP. I can part 2 inch solid round no problem. The only time it vibrates is when I cut too slow. Faster feed rates work better for me.