My favorite part of all of your videos is to be able to look over the shoulder of an experienced professional machinist and see how he thinks about problems. I cannot speak highly enough about your description of holding the taper blank. So much insight. Thank you for these videos.
Agreed. Stefan takes the time to explain why some things work so much better than others, like the zig zag oil ways. It makes sense when you think about it but it is not always apparent.
Your experience shows well. I was once told about the levels of training available for trades in Germany. In the US many years ago, the apprentice machinist program was dropped.
Great video Stefan! Your cutting tool can also add or put stress back into a perfectly stress free material. In fact probably most of the stress you encounter in machining is probably caused by what you do. Not actually in the material in the first place. I have seen this quite often when facing thin-ish material with inserted face mills. The part will bow up into the tool. The inserts are expanding the face of the material. It is actually better to face such parts with a smaller diameter and freer cutting tool/endmill with more passes. It will tend to put less stress into the part.
Fully agree! We rarely use inserted tooling in our VMC when machining parts for tool/die and moldwork. Facing is usualy done with a good 16 or 20mm finishing endmill. Grinding can also put quite a bit of stress back in material, especially when the wheel is not cutting free.
@@chris0tube There is indeed stress in materials depending on the way they were manufactured. This will be released when material is removed. What I am talking about is. Every cutting tool induces stress back into the material. Depending on the tool some more than others. Although coolant and the bluntness of the cutting edge do play some part. This isn't the whole story. Every tool pushes some metal back into the cut thus creating a compression in the surface of the cut. As Stefan indicates even a dull grinding wheel will do this. Here is where coolant or the lack of it will even exaggerate this because heat also expands the same surface being cut. You can see a similar effect in a sand blaster. take a piece of sheet metal and blast one side. It will bow the sheet toward the side that's blasted. Or I have seen shafts straightened by peeing with a hammer on the surface. This is the same effect that the cutting tool has when it cuts. The more negative rake or lack of a keen edge the tool has the more it will push metal into the surface its cutting. This is also why ever tool leaves a burr on the edges of its cut.
In my youth, I watched a film about "weathering" of castings, I think it was by the Colchester lathe company, and the point is, that they left their lathe bed castings out in the open, in wind, rain, frost and snow for a couple of years to let them find their optimum stress relieved position. They then rough machined the casting and left it AGAIN, before finish machining. That is probably why a lot of their machine tools are still in use today, and are still as accurate as they were when new. As has been stated any machining will impart stress , but with careful tool selection the stresses imparted can be minimised and a fine machine tool, well maintained, can last a very long time.
Well ,a lot of wisdom here.No nonsense no promises.Just straight talk about how things work.Thats why I like your channel.I'm 75 years old and have listened to a lot of bullshit and produced some myself and have found it goes nowhere.Keep doin the "Hard stuff"Thank's
I didn't think anyone could make 35 minutes of gibs interesting but you did it! Very interesting and informative. I especially liked the info about oil grooves. Thank you for spending your private time educating us! Very kind of you! I look forward to more! :)
For those curious, the potential error when measuring a tapered surface with calipers like that is proportional to the tangent and/or cosine of the taper angle, depending on what sort of errors you make. If you accidentally hold the calipers flush against the tapered surface instead of the flat surface, your calipers will read high by (1/cos(angle) - 1)%. If you hold your calipers correctly but do not place them in the correct location as Stefan showed, then your measurement will differ by the tangent of the angle multiplied by the distance shifted. If you have a 5 degree taper and the true measurement is 5 millimeters, then holding the calipers wrong will result in a 5.019 mm reading. Shifting the calipers 1 mm to the high side will give you 5.087 mm. Doing both will produce a reading of 5.10 mm. Assuming I didn't flub the math, of course.
Back in the day (lord I sound OLD) we had a set of master tapers we would use to make Tapered Gibs. These were in a variety of tapers. .250 per foot etc. To rough machine the gib we would do the work on the shaper. Finish work was usually surface ground and then scraped. The only problem with scraping ground surfaces is unless you have a very sharp scraper it is hard to get the initial scraping passes to grab the surface. The scraper wants to just skip over the surface. The worst part was when we had to make gibs out of Ampco (Aluminum Bronze). If you weren't careful about heating the work everything would be find and then suddenly, BOING!, you'd have a bend.
Verifying oil grooves. In my past dealing with high rpm gearbox shafts using 3 part tilt pad bearings required 15 degree chanfer that allowed lubrication oil to enter the leading edge of bearing shoe contact areas. Shaft speeds were beyond the capability of ball bearings.
There's SO much extra packed into your video's Stefan. Machining hints and tips, useful jigs and even hints about how to relax ..... not to mention advice on not stealing - at least not stealing parallels. Brilliant. Absolutely brilliant. BobUK.
Really appreciate all the detail and explanation on how something should be done and why. Every video helps make me a better machinist. Thank you for sharing your knowledge so selflessly.
a couple ideas for measuring that taper. 1: use an indicator to measure the rise over run of the part. I've had good experiences with this method. 2: use a ball between your anvil on the micrometer and the part. This has also served me well in the past.
Another way of holding tapered parts is to make one extra sacrificial tapered part and super glue it in the opposite direction to the one you want to machine. That way the combined pieces can fit in the parallel jaws of a normal vise.
Thanks Stefan, always good to learn something different. I think I now know what a gib actually does in a machine tool now! I work in another field, but always nice to learn from other trades. Thanks for taking the time to share your work!
I find that quite a good way to hold rough sawn stock in a machine vice is with thin lead sheets between the jaws and the cut faces. For rougher workpieces the lead can be folded (by hand) in places where it needs to be thicker. If a thicker rectangular block is needed it's a simple matter of creating a 'Swiss Roll" and then squashing it flat.
Nicely presented Stefan. It is a fairly involved process to build gibs. Your description of the geometry was very clear. I like the set up you devised to cut the bevels. Some day I need to get a tilty table. (and of course scrape it!)
To be pedantic: it's trivially possible to remove all stress from a material: just make sure it's not a solid. Liquids, gases, and plasmas inherently have no stress. Not sure about more exotic forms of matter, but if you turn it into degenerate matter to find out you'll win at least a Nobel prize!
Love your method to hold the tapered parts. When I worked for Reynolds, the toolroom would measure tapers with gage pins on the top surface, fixed at a known distance apart. Subtract the diameter of the pin.
Excellent as always! Its really hard to focus on work when you have new SG video waiting for you in the morning. But you have to set up your priorities right... Thats why I'm here watching it! Haha :)
Great info. I need to mill some oil grooves into my lathe cross slide as there is no oil nipple/system in place. (Other than trying to squirt oil up from underneath which doesn't work well) So it looks like I'll be making a custom cutter for that!
I think thats what machining comes down to ;) Everybody can take a huge cut, removing a large bulk of material when its held perfectly in a large hydraulic vise. But with tricky stuff like a long taper, well, thats a different story.
Excellent set-up with the double matched vice, like the idea of the ability to stagger them. May I ask would fitting the magnetic chuck from the surface grinder on the milling machine be a solution, if you have the Z height capacity?. Wunderbar, as normal. Thanks for sharing and best regards from the UK.
Stefan , interesting video , thanks . Tip . to check a taper , a micrometer ball attachment can be put on a micrometer. will not give a perfect reading but way better than two flat surfaces . hope this helps. John
Thank, good to hear. I try to compose my videos in a way that everyone mechanicaly inclined can learn at least a tiny bit from it, even if he never has to do the task shown.
Great video! Boy Alibre has come a long way with the UI. That's the dirty secret of the cad world. They all use very similar kernals and it's lots of UI usability and automation
love your videos. can you add the german names for some of your bought stuff: like the oilgroove cutter or the precision magnets, I can't find it anywhere.
The small one seen in the video I did a exhausting long video series on - But it was built without a surfacegrinder. Only mill/shaper/toolpostgrinder. Today I would have more/different options to get them more precise. I might revisit them.
For oil grooves, how about using a ball endmill and not plunging it in the full radius? That way the angle on the edges would be more shallow. Then maybe grind or scrape away the residual edge and it should be good.
Stefan could you hold the gibs using a regular setup in the vice and simply rotate one gib in the opposite directions so that the 2 gibs combined cancel the taper out and then just set the vice to the desired offset? Great video as always!
Stefan, your commentary is always very precise, there was no need for the drawings and the visual aids. As machining itself adds stress to a part.. would you do a video on the basic techniques of high precision machining? Thank you!
I would have done the bevels before the taper; Keith Rucker did bevels before tapers (and also used a compound magnetic vice). There are problems with doing the bevels before the taper and vice versa, so it's probably just a question of order of operations and how you choose to hold the gib during machining/ grinding.
Hi folks. I worked out the approximate error in misplacing the micrometers on the taper. It's about 30 microns at each end with anvil centred over tick marks. Might cancel out, might add together depending on placement. So, in Stefan's world, it's significant. This guy works to 10 microns on a milling machine! (Assumes 5 mm wide mic anvil - use half that in calculation - and 2 mm in 170 mm taper - think I got it right!) BobUK.
Haven't yet watched through the video (but as usual I figure it will be high quality video), I hit stop on the dust extraction issue because I had a question. I wonder if it's more effective with a shop vac setup like Stefan has, or a would woodshop dust collector work better? When working with wood and dealing with the fine dust generated a dust collector is preferred because while it has less suction it moves a much, much bigger volume of air and creates a "negative volume" of air around the machine that makes all air borne particles move towards it and prevents them migrating around the shop and giving everything a fine layer of dust. And never mind your lungs. I am not sure the same applies to cast iron particles, if they are bigger and heavier and will fall down, then more suction is better. Anyone know the nature of the dust, are they fine enough to be suspended in air or are we talking bigger bits?
My favorite part of all of your videos is to be able to look over the shoulder of an experienced professional machinist and see how he thinks about problems. I cannot speak highly enough about your description of holding the taper blank. So much insight. Thank you for these videos.
Thanks a lot!
Agreed. Stefan takes the time to explain why some things work so much better than others, like the zig zag oil ways. It makes sense when you think about it but it is not always apparent.
Your experience shows well. I was once told about the levels of training available for trades in Germany. In the US many years ago, the apprentice machinist program was dropped.
These videos bring a kind of rational order to the chaos of the world. So much order. Very precision.
666 degrees C - the temperature of the beast.
6, 6-6, the heat of the treat!
Great video Stefan! Your cutting tool can also add or put stress back into a perfectly stress free material. In fact probably most of the stress you encounter in machining is probably caused by what you do. Not actually in the material in the first place. I have seen this quite often when facing thin-ish material with inserted face mills. The part will bow up into the tool. The inserts are expanding the face of the material. It is actually better to face such parts with a smaller diameter and freer cutting tool/endmill with more passes. It will tend to put less stress into the part.
Fully agree!
We rarely use inserted tooling in our VMC when machining parts for tool/die and moldwork. Facing is usualy done with a good 16 or 20mm finishing endmill.
Grinding can also put quite a bit of stress back in material, especially when the wheel is not cutting free.
@@chris0tube There is indeed stress in materials depending on the way they were manufactured. This will be released when material is removed. What I am talking about is. Every cutting tool induces stress back into the material. Depending on the tool some more than others. Although coolant and the bluntness of the cutting edge do play some part. This isn't the whole story. Every tool pushes some metal back into the cut thus creating a compression in the surface of the cut. As Stefan indicates even a dull grinding wheel will do this. Here is where coolant or the lack of it will even exaggerate this because heat also expands the same surface being cut. You can see a similar effect in a sand blaster. take a piece of sheet metal and blast one side. It will bow the sheet toward the side that's blasted. Or I have seen shafts straightened by peeing with a hammer on the surface. This is the same effect that the cutting tool has when it cuts. The more negative rake or lack of a keen edge the tool has the more it will push metal into the surface its cutting. This is also why ever tool leaves a burr on the edges of its cut.
In my youth, I watched a film about "weathering" of castings, I think it was by the Colchester lathe company, and the point is, that they left their lathe bed castings out in the open, in wind, rain, frost and snow for a couple of years to let them find their optimum stress relieved position. They then rough machined the casting and left it AGAIN, before finish machining. That is probably why a lot of their machine tools are still in use today, and are still as accurate as they were when new. As has been stated any machining will impart stress , but with careful tool selection the stresses imparted can be minimised and a fine machine tool, well maintained, can last a very long time.
Stefan Gotteswinter is it because of this most machine tables are planed instred of milled?
@@EdgePrecision that why lapping is soo cool! Almost 0 force
Well ,a lot of wisdom here.No nonsense no promises.Just straight talk about how things work.Thats why I like your channel.I'm 75 years old and have listened to a lot of bullshit and produced some myself and have found it goes nowhere.Keep doin the "Hard stuff"Thank's
Feel free to go into the excruciating details. That's why we come to watch you ;)
I didn't think anyone could make 35 minutes of gibs interesting but you did it!
Very interesting and informative. I especially liked the info about oil grooves.
Thank you for spending your private time educating us! Very kind of you!
I look forward to more! :)
For those curious, the potential error when measuring a tapered surface with calipers like that is proportional to the tangent and/or cosine of the taper angle, depending on what sort of errors you make.
If you accidentally hold the calipers flush against the tapered surface instead of the flat surface, your calipers will read high by (1/cos(angle) - 1)%. If you hold your calipers correctly but do not place them in the correct location as Stefan showed, then your measurement will differ by the tangent of the angle multiplied by the distance shifted.
If you have a 5 degree taper and the true measurement is 5 millimeters, then holding the calipers wrong will result in a 5.019 mm reading. Shifting the calipers 1 mm to the high side will give you 5.087 mm. Doing both will produce a reading of 5.10 mm.
Assuming I didn't flub the math, of course.
Back in the day (lord I sound OLD) we had a set of master tapers we would use to make Tapered Gibs. These were in a variety of tapers. .250 per foot etc. To rough machine the gib we would do the work on the shaper. Finish work was usually surface ground and then scraped. The only problem with scraping ground surfaces is unless you have a very sharp scraper it is hard to get the initial scraping passes to grab the surface. The scraper wants to just skip over the surface. The worst part was when we had to make gibs out of Ampco (Aluminum Bronze). If you weren't careful about heating the work everything would be find and then suddenly, BOING!, you'd have a bend.
mpetersen6:
Same, but used to diamond lap @ 1200 on first finish pass and 2000 grit on the final finish pass. Sent off for final scraping though.
Aluminium Bronze is indeed a pain to scrape, I used to scrape Copper as well, blunts high speed steel very quickly, mainly due to chemical reaction.
Verifying oil grooves. In my past dealing with high rpm gearbox shafts using 3 part tilt pad bearings required 15 degree chanfer that allowed lubrication oil to enter the leading edge of bearing shoe contact areas. Shaft speeds were beyond the capability of ball bearings.
Very skilled professional at work. Your videos are an absolute joy to watch and learn from.
Thank you!
There's SO much extra packed into your video's Stefan. Machining hints and tips, useful jigs and even hints about how to relax ..... not to mention advice on not stealing - at least not stealing parallels. Brilliant. Absolutely brilliant. BobUK.
your thought process for holding your work is simply amazing. I enjoy watching you work!
Crisp, thorough walkthrough from start to finish. Very cool to watch.
Really appreciate all the detail and explanation on how something should be done and why. Every video helps make me a better machinist. Thank you for sharing your knowledge so selflessly.
a couple ideas for measuring that taper. 1: use an indicator to measure the rise over run of the part. I've had good experiences with this method. 2: use a ball between your anvil on the micrometer and the part. This has also served me well in the past.
Groovy video Stefan! Thanks for the oil grove tutorial quiet informative and useful.
Thanks for another excellent and interesting video Stefan.
Great information Stephan, thanks for your time & knowledge. Cheers, Doug
They say that confession is good for the soul, thanks for sharing three of your many vises. :)
Thanks, I always enjoy watching and listening to your videos. Nice work holding setup.
Another way of holding tapered parts is to make one extra sacrificial tapered part and super glue it in the opposite direction to the one you want to machine. That way the combined pieces can fit in the parallel jaws of a normal vise.
Thanks Stefan, always good to learn something different. I think I now know what a gib actually does in a machine tool now! I work in another field, but always nice to learn from other trades. Thanks for taking the time to share your work!
Great video Stefan! I learn new stuff every time.
Yay!!! Another Stefan video!! I still learn something every time
Another fantastic video, once again I learn something I can apply in my own workshop, much appreciated, thanks.
thank you, I particularly enjoyed your discussion on why you use only one reference surface and explained the detail in CAD.
Stefan, you are a gifted teacher.
really enjoyed, thank you for your time in filming and producing this video....LOTS of lessons
Thanks Chuck!
Excellent work. You took the fear factor away!
many thanks for showing all this Stefan
Another great video! Thank You for continuing this work!
I just love your presentations, you have an excellent teaching manner that is very agreable, thanks from Australia
I find that quite a good way to hold rough sawn stock in a machine vice is with thin lead sheets between the jaws and the cut faces. For rougher workpieces the lead can be folded (by hand) in places where it needs to be thicker. If a thicker rectangular block is needed it's a simple matter of creating a 'Swiss Roll" and then squashing it flat.
Thankyou for your wisdom as always Stefan, loved the video :)
Not sure if it hits everyone the same, but, your jokes get me everytime!
Are these nude virgins rare now lol
Excellent teaching, Stefan! Thank you.
G’day Stefan excellent video as always, very much appreciated. Cheers
Peter
Will always remain a student to your methods, always amazed enjoyed !!! Much thanks!!!
Ok, i will not steal parallels. I promise. Nice video, Stefan. I enjoyed.
Good live decision!
Thanks for watching :)
Stolen parallels are unreliable anyway.
Brilliant video on complicated topic , well done, thanks for posting 👍
Nicely presented Stefan. It is a fairly involved process to build gibs. Your description of the geometry was very clear. I like the set up you devised to cut the bevels. Some day I need to get a tilty table. (and of course scrape it!)
As usual, great video Stefan!
Hi Stefan, Thanks for giving us your time. Great video as usual. It would be great if you did a follow up video on scraping in gibs.
To be pedantic: it's trivially possible to remove all stress from a material: just make sure it's not a solid. Liquids, gases, and plasmas inherently have no stress. Not sure about more exotic forms of matter, but if you turn it into degenerate matter to find out you'll win at least a Nobel prize!
If you can get a plasma-gib to work at normal room conditions, the nobelprize will probably be the least they should give you ;)
@@StefanGotteswinter I never said it would be useful! Stress-free, yes. Useful, not so much.
thank you sir. there is some really good stuff to digest here.
Love your method to hold the tapered parts. When I worked for Reynolds, the toolroom would measure tapers with gage pins on the top surface, fixed at a known distance apart. Subtract the diameter of the pin.
work holding at its best, what a good solution well done
23:07 "the wrong one on the right and the right one on the left" love it 😂
Always interesting and very informative. Thank You!
Excellent as always! Its really hard to focus on work when you have new SG video waiting for you in the morning. But you have to set up your priorities right...
Thats why I'm here watching it! Haha :)
Thanks for another wonderful lesson
This is fascinating and after seeing the gibs on my equiv mill I would love to do some workon them
Great job & an excellent video Stefan. regards from the UK
One of your best and funniest. Thanks.
Nice information on oil grooves. thanks
Got to admit, we get a kick out of excruciating. Well explained as always. Regards
Great info thanks Stefan.
21:39 I admire all these flaked/scraped surfaces on that vice. Cheers!
Good stuff as usual
Great info. I need to mill some oil grooves into my lathe cross slide as there is no oil nipple/system in place. (Other than trying to squirt oil up from underneath which doesn't work well) So it looks like I'll be making a custom cutter for that!
Also, no matter how old and wise you are, magnets are just fun to play with
It's not what you can cut, it's what you can hold.
I think thats what machining comes down to ;)
Everybody can take a huge cut, removing a large bulk of material when its held perfectly in a large hydraulic vise. But with tricky stuff like a long taper, well, thats a different story.
Excellent set-up with the double matched vice, like the idea of the ability to stagger them. May I ask would fitting the magnetic chuck from the surface grinder on the milling machine be a solution, if you have the Z height capacity?.
Wunderbar, as normal.
Thanks for sharing and best regards from the UK.
Stefan , interesting video , thanks . Tip . to check a taper , a micrometer ball attachment can be put on a micrometer. will not give a perfect reading but way better than two flat surfaces . hope this helps. John
I will never have to replicate this activity and yet I have learned so much.
Thank, good to hear. I try to compose my videos in a way that everyone mechanicaly inclined can learn at least a tiny bit from it, even if he never has to do the task shown.
Thumbs up for the double vise setup alone.
Nice set up milling the angles . Cheers .
Great video! Boy Alibre has come a long way with the UI. That's the dirty secret of the cad world. They all use very similar kernals and it's lots of UI usability and automation
VERY interesting... thanks for sharing!
thank you for showing oil groove end mill
I would love to see you make a sine bar. I would learn a lot
He did some already.
When measuring a "flat taper" you can use a ball (or half a ball) to get a better measurement
The only Acceptable stress relief is if it’s carried by the Princess of the dawn I heard...
Accept-ed!
Sometime U do what you have to...
\m/ \m/
As Always, enjoyed..
Svaka čast MAJSTORE
another great video thank you for sharing
It actually takes ~1020 kg rather than 981 kg to produce 10 kN on earth; the 9.81 m/s² is "applied the other way around". That's a technical term.
Technically one is a force the other is a mass, with weight being a force. But this is being overly pedantic, everybody would understand regardless
Urgs! You are right!
Ah just talk to a structural engineer 1 t = 10 kN. Because lazyness
love your videos. can you add the german names for some of your bought stuff: like the oilgroove cutter or the precision magnets, I can't find it anywhere.
A video about building a sine bar sounds interesting.
The small one seen in the video I did a exhausting long video series on - But it was built without a surfacegrinder. Only mill/shaper/toolpostgrinder.
Today I would have more/different options to get them more precise. I might revisit them.
He already did.
Little known facts about lesser known subjects is why I come here!
Very enjoyable,thank you..
"Elongated potato chip" (smirk!). You are truly a master of the machining metaphor.
For oil grooves, how about using a ball endmill and not plunging it in the full radius? That way the angle on the edges would be more shallow. Then maybe grind or scrape away the residual edge and it should be good.
Nice vid, thanks!
Glad I just sold my last stock of 100 year old outdoor nude virgin cast iron. Prices have plummeted after your comments in this video.
Was there some question that the nude virgins were not actually virgins?
Great video. Any reason you true up and cut the taper with a small endmill vs a face mill? Thank you for sharing. I always learn a lot from your work.
Stefan could you hold the gibs using a regular setup in the vice and simply rotate one gib in the opposite directions so that the 2 gibs combined cancel the taper out and then just set the vice to the desired offset? Great video as always!
Gut gemacht.
Good stuff Stefan!
ATB, Robin
Thanks Robin!
Thanks Stefan,
Are there micrometers that have double ball anvils?
Thanks for sharing, enjoyed.
Cheers
Stefan, your commentary is always very precise, there was no need for the drawings and the visual aids.
As machining itself adds stress to a part.. would you do a video on the basic techniques of high precision machining?
Thank you!
Or maybe every situation requires its own special care.
By the way If I ask a noob question don't hesitate to tell me lol
I would have done the bevels before the taper; Keith Rucker did bevels before tapers (and also used a compound magnetic vice). There are problems with doing the bevels before the taper and vice versa, so it's probably just a question of order of operations and how you choose to hold the gib during machining/ grinding.
excellant
anyone seen my long parallels? I think someone walked-off with them... :)
Have you seen my braaaaaaaand new large parallels? ;)
Hi folks. I worked out the approximate error in misplacing the micrometers on the taper. It's about 30 microns at each end with anvil centred over tick marks. Might cancel out, might add together depending on placement. So, in Stefan's world, it's significant. This guy works to 10 microns on a milling machine! (Assumes 5 mm wide mic anvil - use half that in calculation - and 2 mm in 170 mm taper - think I got it right!) BobUK.
Haven't yet watched through the video (but as usual I figure it will be high quality video), I hit stop on the dust extraction issue because I had a question.
I wonder if it's more effective with a shop vac setup like Stefan has, or a would woodshop dust collector work better? When working with wood and dealing with the fine dust generated a dust collector is preferred because while it has less suction it moves a much, much bigger volume of air and creates a "negative volume" of air around the machine that makes all air borne particles move towards it and prevents them migrating around the shop and giving everything a fine layer of dust. And never mind your lungs.
I am not sure the same applies to cast iron particles, if they are bigger and heavier and will fall down, then more suction is better. Anyone know the nature of the dust, are they fine enough to be suspended in air or are we talking bigger bits?
Thank you.
hyperbolic paraboloid is the name of the shape of a potato chip. Very useful tips and information video, thanks fo sharing
I need a double like button!!!
stefan why dont you have pinch clamps on you tilt table they are like a mini vise in the t slots