ER40 Collet Block

And shipping is $79 AUS to the US
 
$79 shipping! No thank you. I couldn't even see the shipping cost, said $25 but I'm sure that is not right as their checkout has no field to entire in city or country. Cool idea but I'll pass.
 
I tried to square up the errant collet block but was not satisfied with the results. I could not work out a sufficiently accurate method of locating it relative to the collet hole. And I discovered that the fixed jaw of my economy vise was not exactly perpendicular to the vise base.

I recently purchased a collet block from Little Machine Shop. It is much more accurate - and hardened. I think I paid about $40. I'm pleased with it.
 
Put a gage pin in the collet. Place on surface plate and measure the top of the pin, then rotate the block and check again. Take pin out rotate and try it again to see if it repeats.
 
Put a gage pin in the collet. Place on surface plate and measure the top of the pin, then rotate the block and check again. Take pin out rotate and try it again to see if it repeats.
This is a good idea. Just by goofing around with a file, you can make a huge improvement over the 0.010" that you were experiencing.
 
I have a set of the cheap "soft" hex and square ER40 blocks, Curiosity led me to check them out. The worst I could find was .0015 out-of-concentricity. Not outside my standards. (I don't attempt projects that need ±.000 concentricity.)
 
I attempted to repair the original collet block as follows:

I installed a 3/4" collet and put an 8" length of 3/4" precision shaft through the collet. I set up the collet block suspended by the shaft on two V-blocks on a surface plate. I placed a vise under the block and with the block still suspended by the shaft I clamped the block in the vise. Then transferred the vise/block assembly to the milling machine table and faced the top block surface. Then repeated this procedure 3 more times for the other three surfaces.

The results were an improvement but still not satisfactory. I believe the issue was a lack of perpendicularity on the fixed jaw of my economy vise. I could have repeated the procedure with a precision screwless vise, but at that point I chose not to waste more time on the block.

Anyway, the message that I was trying to convey in my previous post is that Little Machine Shop has good ER40 square collet blocks for a good price.
 
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Most will laugh at how I use my square collet block for but here goes lol . I keep the 4 jaw chuck on my lathe most of the time so if I’m doing things that might want to use a collet chuck for ( which I don’t have ) I just stick a ground rod in the collet , use soft aluminum strips on the chuck jaws , indicate the pin , then I’ll use whichever size collet I need . Comes in very handy for the stuff I do . I have used it in the milling machine but not nearly as much . Since your not happy with that block it would work fine for that purpose
 
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The results were an improvement but still not satisfactory. I believe the issue was a lack of perpendicularity on the fixed jaw of my economy vise.
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How much is the vise off? This sounds like a more pressing ( :) ) issue.
 
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