Shoptalk #28
ฝัง
- เผยแพร่เมื่อ 27 ก.ย. 2024
- 00:00:07 Intro, Blabla
00:01:01 Spline drive alignment
00:09:38 Thermal growth
00:15:01 Deckel machine lineup
00:31:54 Spherical turning
00:42:54 The End
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love the shop talks and really liked that radius setup! is the error from the "straight" section of your radius? ie the tool length? mount the tool on the bar and pin-slot it to the toolpost? I'm surprised your tailstock quill and taper lock well enough to drive the carriage under power cross feed. maybe i need a new lathe, lol. anyway, enjoyed!
This Old Bro, you need to post more videos
Left this comment on Stefan's comments, but you would certainly be another that could produce a nice, clear presentation of "fits".
"You mention something in this video that I'm not very "brushed up" on. You used the term "sliding fit". I've looked and have never really found a good video on "fits", sliding/slip/press/etc."
I really dig these shop talks.
Thank you Stefan especially for the radius turning tip, going to store it in memory for future use👍
Nice subjects! This is how some of us learn the most by listening to people experienced like yourself! Thanks for posting and take care!
Thank you once again Stefan, I so enjoy your work and presentation. It's the first time I've seen the door to your patio open, what a wonderful working environment. So much nicer than a basement!
The large radius turning idea is absolute genius.
I’m a simple man - I see new content from Stephan, I automatically thumb it up and feed the algo before even watching.
Indeed!
Same
The computer knows you didn't watch it first so probably doesn't work.
Oh, come up with something new once in a while!
Feed the algo. 👍
I really enjoy your shoptalk videos,so many usefull bits of information and handy tricks for hobby machinists to learn from you,however my ebay searches after your videos will surely bankrupt me ! Thankyou Stefan
I feel your pain. e-bay with a credit card is one of the most dangerous places on earth. 👍🤣🤣 I'm a hobby machinist too and anytime I watch a machining video I see something else I just have to have.
Always enjoy these shop talks Stefan, thank you for uploading my friend. 👍👍
Deckel's fascinate me, and when you and Michel are using them, i am in awe every time. No, not on my bucket list to own one, but will continue to enjoy you that do have them. Bear in TX
The radius turning idea is pretty ingenious. I like how your brain works.
Being a machinist of optical assemblies, I was screaming "spherometer" when you started discussing the metrology of spherical curvatures.
Of course the indicator depth on a spherometer is known as an algebraic function of the radius. No need to cheat with CAD.
Another method would be to polish and set up the shiny concave item as an autocollimator, such as with a camera on the carriage, and using the DRO to measure the focal length.
The Deckel system diagrams remind me of the Zeiss microscope system diagrams. Very much a German style of modularization, reuse, and scaling.
As usual fantastic work. I really love this Mill and also your surface grinder. To the point of hating you. :) Also your methodology is top drawer. Jeep it up.
31:54 I can't believe what I just saw. You sure could have done this with a profile cutter. 😉
Thanks for showing this great idea! 👍
With a shiny concave part like your spherical mirror, the other easy way to determine spherical radius is to measure the focal length!
There are a couple simple ways to do this:
Use a point source like a small lamp, LED, or a light behind a sheet of paper with a small hole. In a darkish room, move the spherical surface away from the light source/flat plane, until the light reflected off the mirror forms a point. The distance between the mirror and the point/light source is your focal length, and also the radius of the surface.
Or, look at the sphere, line the reflection of your eye up in the center, and move the mirror away until your eye gets giant. When it's as big as it gets, the reflection will flip. At that point the mirror is one focal length/radius away from your eye.
Wow, thanks for showing the extent of thermal expansion. I never paid it much attention...I will from now on.
🏅
Thanks Stefan! Always enjoy Shoptalk.
Stefan, Your videos bring a lot of usefull information, and what is even more valuable is Your out of box approach. Keep it that way, my admirations!
Du wolltest nie eine FP1 haben, und jetzt bist Du Fan!
Die Dinger sind schon sehr universell und gut ausgedacht. 👍
Danke fürs Zeigen des Kataloges!
Gruß Larry
Lustigerweise war ich immer Fan von den Maschinen, alleine weil ich beruflich immer FP1-FP3 zur Verfügung hatte - Ich wollte nur keine weil sie teuer sind, Ersatzteile teuer sind und Zubehör teuer ist :D
Aber die Prioritäten ändern sich halt im laufe der Zeit, das Ding ist jetzt meine Midlifecrisis-Fräsmaschine :D
Saturday morning SG.....👌, stoked on the channel👍👌🇦🇺
Very ingenious cutting of that 400mm radius. Great stuff!
Most of what you do is way above my head, Stefan, but yet again gobsmacked by the setup. Pure machinist TH-cam Gold. Vielen Dank.
Good morning Stefan. I look forward to your videos. This one sounds like it is going to be very inventive. Also having watched some so far - educational. It's also interesting to see some of the history about tooling you have. Thank you for taking all the trouble to film this episode and the many others. The macro filming must be quite fiddly. Love the throw away lines as well!
I really enjoyed the Deckel catalog chat. Thanks for showing that. And, of course for all the rest too :)
Those copy milling machines look really fun, would really like to take a closer look at one.
Also, with the spherical turning, you can compensate for the error of the radius simply by making the hole distance in the bar shorter by the value of the tool radius. You would also have to compansate for the radii of the balls you used in you measuring tool in the same way. Since the curvature was really shallow it's easy to get away with ignoring it, but on more curved features you have to take that into account. You can also account for it if you make the radius of the spherical feature smaller by the ball radius of the measuring tool when constructing it in CAD, or you model in the balls as well.
Stefan, that shaft operation is cool, here I always thought they were broached. That is an excellent fit.
I sanded a mirror myself. At that time I had measured the radius of the mirror's curvature with a point light source on the mirror axis and a razor blade: Foucault's shadow test
Interesting topic about that large radius tool Stefan, nifty solution!
You always inspire me to do better with more patience and thoughtfulness! Thanks
Cool trick with the large radius 👍
Excellent video as always! Thank you so much for sharing.
Hello Stefan, interesting compilation. 👍
I have a manual FP4 from the 70's and it surely does have a vertical AND horizontal quill. The machine itself is a beast, although much of the feeling does have to do with the huge table.
That looks like it will make a fine steering shaft.
I think it went in a track-only jaguar.
I almost bought a Deckle Dye Sinker for a song a few years back, in perfect order, with a ton of the tooling and accessories.
I just did not have the space at the time!
They are quite big!
Thanks again for a clear, not to say precise, and informative video.
Thermal expansion of materials not only has an impact on work dimensions but also on work holding. I stumbled on this when I was turning a roller for the craft press I was making for my wife. The material was some 41xx steel and I was roughing the outside diameter for this 200 mm long roller. Pretty simple operation having the work piece between a 3-jaw chuck and a live center in the tailstock. I used a WNMG insert with a depth of cut being like 1mm and feed enough to break the chips orderly. Of course the work piece got quite warm as I was turning it dry. Then my wife interrupted me with the excuse of a dinner and I had some quality time with her. After some 1 hour later I continued turning from where I left it off. The work piece started to rattle and vibrate violently. So what had happened during that one hour?
I noticed quite soon that the live center was loose. So, why would it be loose as I originally tightened it when it was cold? Actually, when that work piece got hot, it expanded and pushed the tailstock a little farther. When it cooled down, the tailstock, of course, did not follow :) ...
The thermal expansion coefficient of most steels are in the 9-12 ppm range and the same figure for aluminum alloys is in the 19-22 ppm range. So aluminum expands double as much as steel.
So let's take an example for that (damned) roller I was turning. The length from the chuck was 200 mm and the change in temperature was about 80 degrees (from 20 to 100 degrees) Celsius. So, if the thermal coefficient would be 10 ppm (for simplicity), the total change in length would be 200 mm x 10 ppm x 80 degrees. This will yield 0.16 mm which is more than enough to loosen the tailstock.
Good stuff Stefan, love the radius setup in the lathe. Making the pin spacing of the radius bar shorter by the tool nose radius will give an accurate part radius.
ATB, Robin
Hi Robin! Thanks, I have to revisit the radius tool, the geometric phenomen, on how the insert radius actually deforms the contour is not entirely clear to me yet.
@@StefanGotteswinter I don't think there is any error if the insert tip is straight on the centerline of the 400mm holder, and the 400mm is from the tip of the tool to the center of the pivot near tailstock, what does change is the stepover per revolution because you're feeding in in a straight line, so stepover is -decreased- INcreased as you get closer to the center, but probably not an issue in this case if there is some radius on the tip of the tool, besides the error is minimized because the infeed point is far away from the pivot point, would have been even less if you moved it closer to the cutting tip
PCD tool had a hefty radius, MCD I couldn't make out
Awesome content, as always!
Loved the sphereometer.
G'day Stefan, Impressive!
German graphic and industrial design is beautiful, well organized, clean and very intimidating. These values are carried out through every aspect of industry. However, when you observe flimsy chairs holding up heavy machinery in Deckel's factory floor, and an assembly line of well dressed workers bolting parts under Porsches while zipping around on office chairs with casters, humor is also valued.
Thank you Stefan, a very enjoyable 43 minutes!
Very interesting radius turning, useful tip!
I know You pinned Your multifix (as I do as well) but perhaps one possibility to get rid of the small error and possibly simplifying the setup could be to let the toolpost rotate and and simply clamp the tool holder and the bar together in the multifix holder. This in my mind should eliminate the error, since the cutting tip will be aligned with the hinge point, the offset rotation of the toolpost should not matter.
Tolle technik für den Radius. Und der Stefan geht auch bouldern, sehe ich. Ich bin Konstrukteur und bouldere seit jahren. Das passt einfach gut zusammen, beidesmal muss man probleme lösen😂
I fell asleep during the brochure part, and didn't wake up until the shperometer. Had to rewind to see the radius turning.
I never use water based coolant... I use the cheapest atf(oil) i can lay my hands on... First, it smells like you are caramelizing sugar when burnt or heated up, second, its oil, not water, so it can not cause rust if left on surfaces...
Its also quite a good cleaning agent in and of it self, making all the machine surfaces it runs down and that get wiped off as clean as if blasted with brake cleaner... Sure, not in a single go, but when its your only coolant, you machines quickly shine up and loose all oxidation or discoloration on any supposed to be bright finish surfaces...
Its essentially hydraulic oil, but unlike many hydraulic oils and low vis. spindle oils, its not as toxic as all hell, it doesnt turn acidic in a hurry like some hydraulic oils do in presence of even a hint of moisture in the air and so on...
I highly advise anyone whenever i get the chance to try it or to switch over to it... It needs less maintenance than water based coolants, it lasts longer(much longer if the system is filtered and not fully open to air all the time...) and while it may be worse in cooling capacity, all the other properties it offers outscale water based coolants in my opinion by a margin and a half... If you want cooling, use the mist system with the same oil and there you go, much less oil usage, much higher cooling and still no chance of rust or any stupid shit... There is a reason why the old automatic lathes which were cam programmed ran and used nothing but mineral oil as coolant... Those were high precision, complex system machines that required absolutely no chance of any complications due to nonsense...
Also, when coolant gets warm or hot, it also evaporates water inside the tank, and if that tank is the machine base or some machine cavity, you are getting moisture condensation within the machine cavity in the area which likely isnt all that immune to rust... Sure, its likely painted all over, so that offers some rust protection, but paint is a poor solution, whereas with oil, if it evaporates in the machine cavity, it deposits a layer of oil on those surfaces and all other surfaces it lands on, granting some rust inhibition as a free gift...
As mechanics say, ``if water in your knee is bad, you dont want it anywhere else``... Also, if you are using or making your own water cooled spindles, you might consider automotive ethylene glycol as an additive, sure its toxic, but its delicious, and that is the point! Jk, its rich as hell in rust inhibitors and the spindle cooling sys. should be a sealed system with water to air cooling via radiators regardless, which should encourage you to use glycol(if you are confident in handling toxic additives(like the ones used to sanitize machine water based coolant...))... It will help the seals hold up better, and it wont rust weld the cooling system over time, and for fucks sakes, if you are in a cold place with a cold shop, i dont need to say that its also called antifreeze, which i dont need to explain the benefits of in using in a costly system that could be damaged by frozen cooling liquid...
Also, Stefan, you are torturing me by reminding me of Deckel LKS/LKB`s, as one got away from me and im still pissed about it, as it was the seller`s fault... An asshat of remarkable magnitude... A fully decked out Deckel LKB with jig grinding and boring heads, full 2 cabinets of tools and ancillary eq. all of it for pennies essentially, and the machine was in a great condition... And she got away as the asshat had multiple sites with multiple buying options(varying per site) and while in process of making the deal with the seller, someone ``buy-it-now``-ed her online, on a site which i didnt know existed, and since the money hit the decks, the asshat despite the legal binding papers being exchanged, took the money as the more legally binding contract and sold her off... I coulda pressed the issue, as the papers he sent me had ``legally binding offer`` which i accepted, written on them, but fuck me, she`s water under the bridge - long gone other than in memory...
Speaking of Deckel, those slant table FP3 variants are very popular for some engine resto rooms, logically, those where V block are the main game... You can mount the flat table and turn the head, you can mount the block to the slant table, you can do the hokey pokey, you can bore, you can deck the surfaces and so on with a lot of ways to approach the fixturing and with lots of options given to you by the machine itself... I dont know of such shops, but i have read quite a few forums where some guys claimed to run such shops and to appreciate such machines highly...
All the best and well lubricated regards,
Steuss
This saved the weekend 👌😊
🥉
The Deckel class was my favorite part. Easily in my top 3 machine tool manufacturers of all time. Manual machines are just too cool.
Hold on to your hat! More deckel brochure content coming!
Nice as always Stefan! For reducing glare, when showing shiny surfaces (for example the Deckel brossure) you can use a polarisation filter on your camera lens :)
Always great content on your channel. Thank you! That KF1 would be fun.
😬👍
I've used/seen used (last job) the PHorn system used in production milling machines running almost 24/7, they're outstanding.
Brilliant....as usual. Nice mix of topics.
Is any one else super confused by this radius cutting method? is the cross slide pinned to the bar? I'm missing something
Stephan, I dont care what anyone else says, You are a badass.
I really like your design for the Spherometer, I was looking at doing a similar measuring tool and turns out, there IS a math equation where you can calculate the measurement of the height/depth of the measured radius, although CAD is always easier 😁
I figured out the math meanwhile :D
But I like graphical solutions.
After getting an approximate radius with the sphereometer, the telescope maker might use a Foucault test to find the exact radius. The general idea is that a point source of light at one radius distance will generate a cone of light that bounces off all points of the mirror perfectly perpendicular, and will converge at a point that is also at the exact radius. If put a knife edge into that cone, it will gradually cut the light if it is in front or behind the radius, because it's slicing into a disk of the cone. When you slide the knife into the exact radius, the diameter of the beam is effectively zero (pretty close), and so the light will suddenly wink out. There are various other factors; telescope makers are usually interested in a parabola, and the detailed shape of the polished surface.
I don't know if you need it or want it, but it's an interesting technique, and I suspect if you did want one, you could pretty easily make a little sled to measure the curvature very accurately.
That said, the machinery to turn the radius was terrific!
Hallo Stefan
Vielen Dank für die lehrreichen Videos!
Ich richte mir zur Zeit gerade auch eine mechanische Werkstatt ein und habe mir soeben eine Deckel S1 Universalwerkzeugschleifmaschine gekauft, wäre schön wenn Du bei Gelegenheit Arbeiten an dieser wieder mal Filmen würdest...
Ich habe das Glück, dass ich einen ebenerdigen Zugang zur Werkstatt habe, und eine Nutzlast von 500 kg pro Quadratmeter, nun steht deshalb auch eine Thule Stossmaschine mit 500 mm Hublänge in meiner Werkstatt:) Desweiteren habe ich eine Aciera F3 Fräsmaschine, wobei ich nach diesem Video lieber eine Deckel FP2 hätte...
Grüsse aus der Schweiz
PS: Lustig dass Du auch Boulderst, ich habe neben meiner Werkstatt gerade mit Kollegen eine Boulderwand gebaut...
Always enjoy your videos, thanks
I learned things today! thanks
excellent video Stefan!
Water based coolant is basically the only thing that allows me to part without ruining my parting tool inserts, granted I use chinese ones.It's a mess thogh but I haven't found a good oil alternative that would put the coolant on the shelf. I've built sheet metal covers for the lathe much in the way you and Robin Renzetti have done, but for the purpose of keeping coolant away. I've also used gasket product like Hylomar blue to prevent coolant ingress where the compound slide mates to the top slide. I found it made its way in there and left rust on it before, not afterwards. My lathe is from the 50s but came with a built in pump and coolant tank.
Diamonds and radius turning? Where are the optics videos? You're next level now man.
That fit was gootentite 😊
indeed
A Buddy in Vienna has KF1 and he always tried to Lure me into Buying it. its quite a Massive Mashine to be honest. But like you say: Super interesting Super Coool Machine
excellent work
Two things I love are Deckel and Bauhaus. I couldn't find the architect of that building. I was hoping it was Walter Gropius.
Very interesting. Thank you. 👍👍👍
Just dropping some names for optical (non-contact) inspection systems for others looking for further research...focus variation + depth stitching, structured light, or interferometry. Non-contact metrology is essential for diamond turning applications. That being said, I'm curious how accurate an xbox kinect/similar imaging methods are.
Thanks for the video Stefan. The radius setup is ingenious.
Ooh, new intro music
Regarding the spline fit: maybe the tightness is due to the interference of the spline's _roots_ & the joint's _crests_. In which case knocking off the burs on the spline's crests wouldn't help.
Thanks! :)
what if there was an odd number of splines?
Like in my example? :D
Then you have a problem. Or you dont notice, like I did in the video.
I like the long radius tool 😃
Hi Stefan, can you do a review on the Mutifix style tool post?
You are incredible! thanks
So- it's all about trying to simplify the geometry of planes. How would this have been done in say a transmission factory? A specialist machine?
You mention something in this video that I'm not very "brushed up" on. You used the term "sliding fit". I've looked and have never really found a good video on "fits", sliding/slip/press/etc.
I habitually cool down parts as I am machining for that very reason regarding part growth.
I have to wonder how many of the optional arrangements for all those machines were actually sold. Thanks for the video about them.
I guess a lot where sold with a full/semi full accessory kit
Good stuff Stefan. I wonder where Hermle got their inspiration for their C20, C30, C40, C50......... Cheers, Jon
I own this large Deckel rotary table you first show. Do the manual specify what power is use to actuate it?
Hmm, I think its 6V, but I can not guarantee it.
Thanks Stefan. I liked the walk through of the Deckel brochure. Who needs an Innolite ;) I'd be interested to see Jeroen at @HuygensOptics measure your spherical surface.
So was the radius pivoting around the toolpost shaft centre? love that radius finder jig!
Love the deckel catalogue tour. I wonder if Stefan has ever came across any Swiss Fluri mills like the really odd SFM2 I am getting in a few days. I was able to find ANY information about it other than the fact that the brand isn't making machines anymore
Sorry, Never heard of them - Fluri seems to make linear transfer machine these days?
Is it possible to counteract the error induced by the nose radius if you slightly change the distance between the holes of the 400mm bar?
Yes if you reduce the radius of the guide bar pivots by the radius of the tool, it should give the perfect form as long as you don’t start to cut on the tool flanks.
I think you could have put a collet block on the spline shaft if you had one? then indicated off that?
Awesome. Thermal expansion has caught us all out at one point, and that radius turning method is mad, but if it works it works.
There's something a bit off in the audio, have you changed something about how you capture and process the audio? Too much bass throughout, and some clipping in your intro.
I am lacking the sound dampening of furniture in my new office space, where I recorded the intro, sorry :-\ The rest of the video should be the usual sound quality (Which needs also work..)
Stephan, the thermal differences is very informative. Will there come a time when Temperature will be specified with margin. is, +.01mm/30C. 😮
Now my brain hurts
Great video as always. I loved the radius turning idea, not seen that before. I do have a query though: Isn't there risk that the drill chuck taper will pull out of the tailstock? Is there a way to mitigate that, or are you just relying on the taper holding?
So, are you making telescopes or breakfast bowls?
Regarding the potential error with the tool: would it be theoretically eliminated by having the headstock end pivot point at the tool tip? Trying to get my head around the error, thanks
How about a cooler using shop air instead of coolant. A desiccant dryer used of corse.
Someone should make a insert drill bit with a chip breaker, those stringy chips are shitty to clean up and dangerous too
Radius 400? Why not 400 - cutter radius? 🤔
Like the fp2 more then the fp1 cause it have a deeper casting ( only reason why I like it over the fp1 )
Hi stephan, a bit of a noob question. I see people swiveling the contact point of their dial indicator. I have a standard mitutoyo indicator, but I found it doesn't go so easy. I'm worried I might break it if I force it. Or should it just work? How much force does it take? I'm not finding any good videos on this and the mitutoyo site doesn't give a good explanation
How would you do a *convex* 400mm ?
Run away screaming and panicking? I dont know off the top of my head. Maybe a template in front of the carriage and a follower bearing.
PKD is of course PCD for many of us .
"Let's do it properly." Translation: "Let's do it German."
Another option for testing such piece is formtester from Mahr sitting in my basement… bought in the past as used, realy expensive, unfortunately as it is special machine difficult to sell. Bad investment for me and too far from Stefan to use it as help.
Comment 41! Love this guy !!! thanks Stefan ✌️💖&💡 via 🇺🇸
⭐🙂👍