I am a rank beginner. My ER32 collets and holder have turned up in the mail. Tried to put them together however the collets didn't appear to go into the holder far enough to allow me to thread the collet holder nut on. Googled the dimensions of the ER32 collets, measured the collets and the holder. Thought the holder was about 1mm (0.04 inch) underbored. Put the collet holder in the lathe, trying to figure out the best way to bore it a little further out. Thought about returning it to Ebay. One more google and I found out that the collet is actually meant to click into the collet holder nut before you try and thread the nut on thereby giving the extra room (Facepalm). Thankfully my final google before doing drastic measures solved my problem. Hopefully some other beginners may learn from my mistakes. On the plus side I've now fitted an end mill onto my milling machine, tried it out on some scrap structural steel and very happy with the results. Will set about making some T-nuts for my first project (currently using clamps to clamp material to the table of the milling machine).
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ER32 Fail (Learn from my mistakes)
- Thread starter xxxx_guy
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That is a classic mistake made by many beginners. Most things are good to go when you get them, if it don't fit, have another look before you mess it up,
You are in the right place here. a very friendly forum and lots of experienced people here to help you learn, Remember the only dumb question is the one you didn't ask.
What machines do you have? and what sort of things do you plan to make?
B
Bill Gruby
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You are not the first to make that mistake and you won'e be the last. As Bob said, you are in the right place. Welcome aboard.
"Billy G"
"Billy G"
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The Force is strong in this one!
Good job.
Just as a reminder to folks, be careful about some of those really bargain-bin, low-cost ER32 collet chucks. I just purchased one with an R8 shank (to use on my other mill) and it's an absolute piece of junk. TIR measuring from the internal collet taper averages about 0.006" (six thou, not six tenths-thou) depending on how it's seated. I thought for a moment my spindle was bent but, a good quality ER40-R8 in that same mill repeatably measures 0.0004" TIR. Sigh of relief!!!
At $26, it's not worth my time/trouble to return it. It's a nice piece of steel and maybe I'll "re-purpose" it.
Anyhow xxxx_guy, good job and thanks for sharing.
Ray
It's frustrating, particularly for a newbie, to see this sort of thing. I bet they advertised it as 2-4 tenths TIR, right? It makes it really difficult to figure out what might be a decent tool for a hobby user that can't spend a thousand or so on a chuck. If it weren't for this site mentioning things like this, I would have wasted precious tool funds on crap that doesn't work. Instead, I waited longer and spent a little more. And I know to double check TIR while still in the return window, particularly for more expensive parts.
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The one I purchased on eBay had no tolerance specs -and that's the problem. The majority of the units on eBay and Amazon cost between $25 to $60 and they all seem to be the same unit. They are hit-or-miss junk.
I finally went with a Glacern (GMT) brand that cited tolerance concentricity specs between the R8 taper and Collet Taper. My original unit (on the other mill) is from Shars and for years, it's been running at basically Zero runout.
An issue that beginners face is knowing how to measure. Reading off the outside body is meaningless. With these types of chucks, I recommend installing on machine then TIR measurement taken from inside the taper (without a collet inserted). Next, take a known set of collets and insert several different size (undamaged) shafts and measure TIR. From this, you can establish a level of understanding. If you don't get good readings, remove, wipe everything down, re-install and check again. From this, you will learn the capabilities of the device.
Note: the oblong ring inside the cap is needed to pop the collet out when the cap is unscrewed. Without that, collets would get stuck in the taper.
When unscrewing the cap of an ER collet, put a rag underneath the tool. The cap will eventually pop the collet free from the taper and your carbide endmill will either chip your table, chip itself or chip your workpiece. (Trust me on this last bit of experience).
Ray
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If you have it in your mind to use the collets to hold drill bits as well as end mills, you need good quality collets and of all sizes both metric and imperial, this way you leave the collet chuck in the mill and just switch the collets when you change the bits.
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Well, I think you probably made the same mistake as me, and every other person who had never seen an ER collet and holder when they first try that 
. On the plus side, most of those Chinese tools are so hard, you probably would not have been able to cut it anyway. I suspect that has probably saved a lot of them.
. On the plus side, most of those Chinese tools are so hard, you probably would not have been able to cut it anyway. I suspect that has probably saved a lot of them.