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jdunmyer
02-09-2008, 05:59 PM
What is the correct procedure for installing a camlock lathe chuck onto the spindle? I know that the tapers must be CLEAN, but what is the sequence for tightening the cams? Does it matter what the orientation is? (IE: does the chuck have to be reinstalled in the same relative location every time?) How tight should the cams be torqued to?

There's a line on the cam that corresponds with a line on the spindle when it's unlocked, plus 2 'V' markings? I'm thinking that the pins should be adjusted so the line on the cam is between them when tight, is that correct?

How about removing the chuck? Is there any special sequence to loosening the cams?

PaulF
02-09-2008, 06:17 PM
Hi,
I just machined a D-4 Cam lock for a new collet chuck.

When you set in the pins there is a line scribed on the pin to indicate depth, then a cap head set screw is put in to lock the pin.
There should be free movement of the pins within the range of the cap head hole.

Where I got caught was that I thought these lines were exact...no way!
I had to play around, when 2 would go in the 3rd wouldn't.

If you play around you will find the sweet spot and all 3 will lock.

PaulF

Oldbrock
02-09-2008, 06:20 PM
no particular sequence and no specific orientation just lightly snug each first and then3/4 tighten then as tight as you can with the supplied t handle. Do make sure they are tight, a chuck coming loose during machining is no a fun time. Peter

ammcoman2
02-09-2008, 08:15 PM
Not sure if it is necessary but I have punched a "1" on the backplate to align with the # 1 pin so that I always put the chucks etc on the same way every time. Did this before skimming the register for each chuck. Haven't bothered with the 4 jaw though.

The books say to screw in the pin up to the line and then turn in more to align the cap screw slot. As PaulF said that doesn't always work!

Geoff

pcarpenter
02-09-2008, 09:31 PM
I worked out the minimum runout of the chuck mount to the backplate (by trying) and then also the minimum runout position of the chuck and mount on the spindle and then marked that so I could put it back each time. This can get you some really good runout numbers if you are willing to put in the time, one time. If your chuck came with a built in mount, you are half way there. On a d1-4, you only have three choices.

In my case I went from about .006" to .0007 or .0009 (can't recall) measured on a ground pin about 1.25" in diameter, a few inches from the jaws.

Paul

mechanicalmagic
02-09-2008, 09:32 PM
That depends on the quality of your machine. Some Chinese lathes have .0005" error in the spindle. If you machined a backing plate true, then you might have a significant error in other positions. If you make a backing plate or have machinable jaws, you should mark the spindle and chuck.

I prefer to tighten a D1-4 finger tight on all cams, then half tight all round, then full tight. I did some testing when I got my last chuck, and fitted soft jaws. The biggest error was different gears to tighten the scroll. (Non Set-Tru design). I now have one gear marked.

jdunmyer
02-09-2008, 10:01 PM
Thanks for the help, I'll keep all that in mind.

One more question: where is a chart that shows the different variations/sizes of the D-type camlock spindles? My friend's lathe has 6 pins, with about 6" across the outside of them.

Thanks again!!

tattoomike68
02-09-2008, 10:10 PM
Thanks for the help, I'll keep all that in mind.

One more question: where is a chart that shows the different variations/sizes of the D-type camlock spindles? My friend's lathe has 6 pins, with about 6" across the outside of them.

Thanks again!!


http://www.workholding.com/BTCMOUNTINGPLATES.htm

Anvils
02-09-2008, 10:14 PM
Jdunmyer, Try www.shopswarf.com/chuckmt.html

good information on several types of chucks

Norm