I have to agree with you - been machining for 20 years and absolutely my take on this issue also .

200% agree. If this gives problems its time to replace the collet.

Agree. I run my end mills flush. If I were to change a tool during an operation I would have to zet my Z axis all over again doing it this way. If I just push the end mill flush with the back and know the measurements I can easily compensate with a little math. (better not say math too loud the younger generation may get scared!) I've never been more than 2 thousandths off yet which yeah that can be alot but still that's a tight tolerance!

@@TheCommo81 2though.. thats 0.58mm? Thats quite a lot! When i make something with these tolerances.. i can scrap it all. Lol

​@@Jbpipesandmufflers 0.58mm is still a tight tolerance. When I do bearing pockets and they are 2 thousandths off I just freeze the bearing in my freezer for an hour and it drops right in. if it's going on a shaft I set the bearing on a 100W light bulb for about 3-4 min and it slides right in. When it cools off it's nice and tight. 2 Thousandths is acceptable to most people. My neighbor has been a machinist for 50 years, 2 thou is the max for him. What I was referencing was placing the tool at the same exact height every time you will know where your tolerance lies when changing tools in the middle of a run.

Your welcome!

Thanks so much for explaining how to put the collet in correctly. I had no idea it could be popped in place or taken out!!! You saved the day!!!!!

That’s awesome! Glad it helped!

Actually the collet snaps into the nut quite easily if you push the collet hold the (empty !) collet at an angle while pushing it in.

or, with long stock... the free end whipping and throwing harmonics down the line... yup, never heard or seen anyone ever say you shouldnt push stock/cutters right into a collet... up until now. where some people get their information from... ffs... this is an example of why one should do a trade or at least read some trade books...

Actually like all thread fasteners, there is a recommended and max torque value that should be abided by. ER collet nuts are very susceptible to cracking because of the tapered interface between the collet and the nut which puts a lot a tensile hoop stress on the nut. Since the vast majority of endmills used daily are upcut design, the cutting action naturally is trying to pull the endmill out of the collet and thus you want as much torque as you can safely put on the nut to generate the most clamping force from the collet but at the same time, you obviously dont want to crack the nut.. Any time one is trying to do very high accuracy / extremely low tolerance machining using ER Collets (or with any type of tapered collet), retention thread torque values should be abided by. Most aerospace industry machining businesses (among others) are very particular about this because of the tolerances they are trying to hold. I've worked for a few places over the years that if you were seen not using a torque wrench and proper values when setting up tools, you faced suspension and / or getting fired. Then again, these were also jobs where loose tolerance jobs where in the +/- a couple tenths (like +/- 0.0002" (or +/-0.005mm) and tight tolerance where in the hundreths (like +/- 0.00005" (or 0.001mm). Beyond that, you were getting into the realm of ground and lapped to size rather than milled but still, a few lb-ft of torque difference can result in a cutter slipping a a tenth or two in the holder and blowing the tolerance. At the same time, many of these industries have gotten away from collet style tool holding and gone to shrink fit and hydraulic tool holders due to their superior retention over collets.

Thank you so much, is there anything else you would like to see from me?

@@cutting-it-close some cnc summer designs or spring matbe ?

You're welcome!

You’re very welcome! I’m guessing you were burning through collets like I was!

@@cutting-it-close yep

I am going to do a video soon of just making a simple bowl with my CNC going at 500 or so IPM with a 1/2 bit, should be interesting!

You are so welcome!

@@cutting-it-close on a piece of 3/4 maple i tried 3 passes first pass being .25" i have tried it in 2 passes as well. right now i've dropped my feed and speeds 18000 spindle 170 feed. still have the freight train sound. not as bad. i think it's chatter and I've tried faster speeds and feeds and slower. gone to extremes holding down my work piece as well. still get it, especially with maple. Up here in canada we pay through the nose for bits. so its is a bit frustrating.(no pun intended lol) by the time i get a whiteside or vortex compression bit delivered im in $60 to $70. i have an opportunity to do a mass cut project for a customer that could make my year. All maple. just worried about taking it until i figure out how to cut more efficient and cleaner im cutting latter today and tomorrow. maybe i'll take a video and send it off to you. more than likely it is something really obvious and i'm over thinking it. Thanks

Try using an up cut bit instead. I just milled 10/4 hard maple with a 1/2” UC end mill. No problems. 1/4” DOC each pass.

Could you be more specific? I can help!

You need to tram x/y using a tramming tool: stupidsimple.tools/products/tramming-tool?variant=38224402776262 Z is only up or down, so any ridges you feel or see are corrected on x or y plane. It is near impossible on any hobby grade machine not to have Machining marks left that does not need a little sanding before finishing. But if you are referring to actual ridges, then tuning it up will help solve the problem.

I got mine from Vortex tools

In principle, the nut needs to move the collet+bit deeper into the taper in order to clamp tighter onto the bit. I suppose if the back end of the bit has already bottomed out it could prevent that from happening, but in reality I doubt it's a problem.