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- Dec 26, 2016
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For those that are using r8 collets for holding drills, how many collets do you have? Thanks
Just in ER 32 collets I have the 20 pcs metric set and 18 pcs of the imperial set.
For those that are using r8 collets for holding drills, how many collets do you have? Thanks
A set by 1/64ths would be ideal but by 1/32nds will work. The worst case is a diameter slightly larger than the collet so the next larger collet would have to close almost .032". R8 collets will close a minimum of .032" (at least, all mine do).For those that are using r8 collets for holding drills, how many collets do you have? Thanks
Would be very time consuming to use just collets for everything. As far as accuracy, it is pretty much moot, as drills will both walk/deflect and their TIR is probably far worse then a decent drill chuck. Get a stub drill set if you want better accuracy/less drill deflection (the difference is very noticeable). Collets may be helpful with larger drill sizes, but as others have mentioned, probably do just fine with a 1/8" increment R8 collet set. Most end mills have standard size shanks. Alternative would be an ER collet set if you want to cover the complete range, they are more collapsible, but I find the TIR can suffer if you are at near their size limits, and also the quality of the collet.
I switch out drills, taps and end mills frequently that even with a power draw bar I mostly use a CNC type keyed/keyless chucks for most drills under 1/2", the chuck TIR is under 0.001". High accuracy milling I will use R8 collets, everything else is a chuck.
Low run out collets and keyless chuck are on my short list. Thanks!I would get a GOOD 13 piece set, like made by Bridgeport and be done with it. And a GOOD drill chuck, like made by Jacobs and be done with that too…Dave.
Chucks mostly, common twist drills do not make accurate holes, if position is important spot the holes with a spot drill in a collet then drill with a chuck and a larger diameter spot drill will also chamfer the hole saving another operation. If a part has 20 holes first spot/chamfer them all then change tools and drill them all, 1 tool change, this saves a good deal of time.The thought process was to use collets with my screw machine drills since I don’t have a chuck for the mill yet. This should produce more accurate holes. Do you use a chuck exclusively for drilling or do you use collets as well? Thanks