Changing bits

[pross]

When it's time to change bits, it's hard to get the collet out of my HSD spindle. Any suggestion?

[harryball]

As in the nut comes off but the collet won't fall out? Or is the nut hard to remove?

If you've had the collet a while, ever dropped it on concrete or had a bit break at the collet edge or inside the collet, replace the collet, they don't last forever. They are only $30 to $40.

I keep my collets clean and wipe them with T9 to prevent rust. T9 is a lubricant but I've found it wipes off well and I've never had a slippage problem.

Robert

[pross]

Nut comes off easily, collet won't fall out. I have to force it out. My shopbot is brand new so age isn't the reason. Does your collet actually fall right out? I have to try to pull it out or put a screw driver on the collet and hammer it out.

[harryball]

Your collet should be snapped into the nut... you are able to remove the nut and the collet remains in the spindle? If that's the case you need to snap the collet into the nut before installing. The collet and nut should sort of be a single piece.

Call me if you like, 770-262-0800

Robert

[henrik_o]

If this is an ER25 setup (and it should be), please note that the nut is excentric: the collet should enter the nut at a slight angle. There is a mark, usually a recessed dot, on the nut to indicate this.

Tilt the collet, press into nut, rotate it into position. To evacuate the collet, slightly rotate with some tilting pressure, it slides right out.

It took me a while to figure this out (it's covered in the manual from, in my case, Colombo) but once you learn it the collet enters and exits the nut with almost no force on your part.

Carefully check the collet you have forced out for any signs of deformation.

[fleinbach]

I do not understand why they don't ship the nut and collet snapped together. I'm sure from just reading several posts over the years here that most people who purchased a spindle for the first time had no idea the collet had to be snapped into the nut.


My first experience created an accident that luckily did no damage but could have been worse. I put 1/2" bit into the spindle to cut the edge of my spoil board for first cut with the Shopbot. I fired it up and was cutting along the Y axis when the bit flew out of the collet and landed in my lap. This was totally unexpected and quite a surprise to say the least. Only after a call to Shopbot did I learn the collet was supposed to be snapped into the nut.

I realize the spindle comes with 2 collets but one should be snapped into the collet nut just to let you know that is how it should be.

[geneb]

Eh? Snapped in? I'm using an HSD spindle and unless my brain is totally fogged, there isn't any way to "snap" the collet into the retaining nut for that spindle. Is this a Columbo only thing?

tnx!

g.

[harryball]

Granted, I can only assume all HSD spindles are the same. I'm running a 4HP HSD and the collet snaps into the nut.

Robert

[cnc_works]

Frank, I can commiserate with you. The first time I got my Elte spindle up and running, it vibrated worse than my old PC with bad bearings. Sorely disappointed and worried, I called the importer who finally helped me figure out that I had not snapped the collet in before tightening the bit. He seemed really surprised that I was not born with that information, but accepted with some good graces my chastisement that it should have been included in the manual. The MANUAL, HAH! A few photocopied pages translated from Italian that basically said "this thing turns and has wires in it".

And then there was the issue of it showing up without even a collet to test it with (ER25) nor a set of wrenches to tighten the nut. That almost turned into an advantage, though. For the nut wrench, I bought a Harbor Freight 1 1/16" box open, cut off the box end and had a wrench that after a little side grinding fit the nut like a glove, slid in and held independently while I messed with the spanner wrench.

So, don't feel alone Frank. Like you, I feel lucky that it was easily solved and nothing worse happened.

Donn

[henrik_o]

Gene, unless there's different ER25 standards, I think the snap thing is when the collet snaps from it's excentric position (a slight angle) into its straight, and final, position in the nut.

I've found that collets/nuts have a different feel to them depending on the brand; the ones I got with the shopbot demand a relatively large angle of insertion to engage the excenter, while my ER25 Metric set bought here in Sweden do not. For the latter, just push and twist and it slides in. There is no real discernible snap for those, maybe that's the kind of collets/nuts you have.

[geneb]

Hrm. I'll have to look at the spare nut I have when I get home tonight. As far as I know, the collet face has never been on the same plane as the nut face. I'll post pics as well - maybe I've got something different. Most likely, I'm doing something really wrong without knowing it and have been VERY lucky so far.


tnx!

g.

[geneb]

Well I feel really dumb. I've been running my bot for over a year with the collet not properly fitted into the nut collar. Der.

I also discovered that my X car is STILL not square.

*grumbles*

g.

[fleinbach]

Gene,

See here for squaring of the X car.

http://www.talkshopbot.com/forum/show.cgi?tpc=7&post=43809#POST43809

[geneb]

Thanks Frank. I was actually reviewing that thread last night after my discovery.


I didn't discover the problem until after I'd spent three days constructing a fancy vacuum jig holder. I put my 12x12 test material in and it didn't fit right.
I'd cut it on my table saw so I knew that part was square. If I'm careful the squareness problem should be easy to correct.

g.