Gallery, Projects and General > Project Logs
Building an ER collet chuck from scratch for a Myford ML7
NickG:
Nice work there Arnold. I have an ER25 collet chuck and collets for my mill, which I am going to make a drawbar for so I can use it in the lathe for small stuff. Should be a good accessory.
DeereGuy:
Nice work Arnold, I have a ton of respect for one that takes on a project like this. Lots of things I have made can be bought also and some that didn't seem available. I always learned a lot during the process and got great satisfaction from knowing I was able to make it....
Looking forward to seeing more.
arnoldb:
Well, had a most productive day today producing scrap.
I received the collets and closer earlier this week :) :
The collets looks OK - I'm slightly disappointed with the closer; it's pretty rough, and full of very sharp edges, so I'll disassemble it and get rid of the sharp edges and see if there is any dirt/swarf in the bearing :dremel:.
On to today's work. I screwed the chuck body onto the lathe spindle, and turned the nose down to start threading for the 32mm x 1.5mm closer thread.
I took the next photo just before I used a parting tool to make a groove for thread run-out:
Then started threading - was coming close to final size and then disaster - cut half of the formed thread away :bang: :bang:
I think the topslide moved - don't know if I accidentally brushed against the dial or what. I was turning the thread using cross-slide feed only - still need to make some clamps and additional markings to use be able to use the offset topslide method, as mine can't rotate enough... :dremel:
So that's one chuck body scrapped :( - might be useful for something else in future.
Then I did something I never do - went into the house, got a beer to cool me down, and brought it back to the workshop to think. Must have still been fuming when I fetched the beer, as I can hear Shrek practicing new words while I'm typing this lot up :doh: ...
On to recovery. One thing I have learned through this (besides to make a plan to lock the topslide :hammer: ) is that my original choice of cast iron might not be the best. I noticed some "chipping" in the spindle thread lead-in, so this piece of CI I have might be too brittle :scratch:. This could potentially cause long-term problems with the much finer closer nut thread. I have an old bolt - used to have a pair of them but the other one was already turned into other tooling. This is nice steel of unknown origin, but it does machine OK:
Shoved that on the bandsaw to get a new body, and gave the lathe a good cleaning while the saw was doing it's job:
Fortunately, I now have all the cutting bits and steps, so next one might be easier
As I had an open beer, further machining was out of the question, so I closed up shop for the day. Tomorrow is another day.... :coffee:
:beer: Arnold
bogstandard:
Arnold,
With regards to your closer nut with the bearing in it.
I personally wouldn't do anything with it, use it as is. It requires those sharp edges for locating the collet and after a few uses, you will find they will mellow down by themselves.
You will also find that the smaller sized collets will be fairly difficult to fit sometimes. That has nothing to do with the collet nut. It is due to the way the collets have to be forced to fit into the nut, and because the smaller sized collets have more meat in them, the harder you have to push to deform them to get them to lock in.
I have been using one of the bearing nuts for a while now, and to me, it is a fantastic bit of kit.
John
sbwhart:
Hi Arnold
I got one of those bearing closer nuts and found it tight same as you, I spoke to John about it and followed his advice, sure enough its eased off.
Stew
Navigation
[0] Message Index
[#] Next page
[*] Previous page
Go to full version