Collets 5c vs. ER vs. MT3 vs. Drill Chuck etc ??

[stioc]

Good discussion. Check this out (skip to 2:34 in the video) - same concept to making soft jaws for cnc/mill work:

 

[BROCKWOOD]

This is a good topic & read! Thought I needed R-8 for my lathe / mill combo, but failed to realize the manual it came with was newer than the unit I received - though it was brand new. So I bought the MT3 collet holder for ER xx (no idea which ER collets they are). They fit, but ate up too much space. So I bought the MT3 collets. Love them. I also bought the 5C collet set with a spindexer & the 4 & 6 sided holders. I needed & use the square & hex holders. So, now I have 2 sets of ER xx that I don't use yet. The MT3 set does fit my tailstock & I'm told I will want to adapt the R8 set to my stand alone mill some day. Does anybody have a chart explaining the differences & showing the measurements on all the various ER Collet designations?

 

[brino]

Here's another good thread to read on collet differences.
https://www.hobby-machinist.com/threads/is-there-a-definitive-article-on-collets.36227/
I believe there was a catlog posted there that gives various collet sizes.
-brino

 

[projectnut]

You do not appear to understand why collet systems were developed.

First came simple work holding, as technology progressed scroll chucks were employed and there was a vast improvement in the number of parts an operator could make in a given day. One may imagine the glee of the first company that used them, "they may clamp and unclamp the parts with the turn of one key and now make 50 parts per day instead of five".

The next improvement was collet systems, place part in collet and pull the lever and the part is clamped without the need of screwing around with a scroll chuck key, "they are now making 300 parts per day". The material manufacturers then had to produce stock with accurate enough diameters and finishes to work well in these machines, also collets allow for automatic bar feeding.

I fail to see why a hobbyist would invest in a collet system to make, as you say, one part at a time. I do fully understand the quest for ultimate accuracy that many desire, however if only producing several parts without a time constraint an adjustable chuck will do everything that you require and more. It is entirely possible that the people that recommend using only a collet chuck believe that this is the only way because that is what manufacturers use.

I have to agree with P. Waller on this one. I'm in the process of making bushings for a Black Diamond drill grinder. I will be making a minimum of 50 or so parts. I couldn't imagine the additional time and tedium it would take using a 3 or 4 jaw chuck. Each piece would have to be dialed in. Even though it only takes 2 to 3 minutes (including time to setup and remove indicator) multiply that times 50 and were talking over two hours additional setup time. With the collet system I just turn the basic dimensions, part it off the blank, index the blank ahead and repeat.

I keep hearing about the Hardinge collets having a + or - .007" clamping range. I have a set by 1/64ths up to 1 1/8". The clamping range on mine are more like +.000 - .015. Last week I took a piece of over size 3/4" stock (.756") with me to a used equipment dealer. I tried to fit it in at least half a dozen different Hardinge .750" collets and it wouldn't fit into a single one of them. I'd like to know what model Hardinge collets have the + or- .007" range. I know at one time they made at least 2 different models. The ones in my set have both internal and external threads. I have a few additional ones I bought used and about half of them don't have internal threads.

 

[mickri]

After considering all of the same options discussed in this thread I bought er32 collets for my mill/drill. I have an er32 to r8 chuck. I chose er32 because each collet has a wider clamping range. So I didn't need as many collets. My lathe came with a complete set of 3c collets. I have never used them. I also bought an er32 to mt2 chuck to use in the lathe tail stock. I use it occasionally. I can also use the er32 to mt2 chuck in the headstock. I have not done this yet. I would like to have an er32 chuck that fits on my lathe spindle, 1 1/2 x 8 tpi, so I could have whatever I am holding in the collet go down the spindle bore. I have not found one ready made and would have to make one. Or make an adapter for one of the ready made er32 chucks.
I have been pleased with the ease of use of my er32 collets. I have found the er32 collets easy to use.

For work holding in my lathe I almost exclusively use a 3 jaw chuck. Occasionally use a 4 jaw chuck.

 

[brino]

I would like to have an er32 chuck that fits on my lathe spindle, 1 1/2 x 8 tpi, so I could have whatever I am holding in the collet go down the spindle bore. I have not found one ready made and would have to make one.

I have this one:
http://www.bealltool.com/products/turning/colletchuck.php

Actually I have had two Beall chucks on different lathes.
Both were great quality.

-brino

EDIT: I had posted pictures of mine here:
https://www.hobby-machinist.com/threads/is-there-a-definitive-article-on-collets.36227/post-308552

 

[bhigdog]

Most accurate and holds the widest range of shapes = 4 jaw
Next for ease of use and size range = 3 jaw
Size limited but repetitive operation ease = collets

Everyone of them has it's uses and strong points and there is a best use for all. If I could only have one it would be a good 4 jaw...............Bob