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mofugly13
08-14-2003, 10:01 PM
I have an older Sheldon lathe model WS56-P. I got it with two three-jaw chucks, a faceplate, a tailstock chuck and a couple of bits for $400. For the last year and a half I've been tooling up via ebay. I finally picked up a dial indicator and decided to measure my spindle runout. With the indicator mounted to the toolpost and the spindle turned by hand, I get .002" of runout.

Since I've mostly used the lathe for making perfectly good brass pipe nipples (or any round piece of metal I can scrounge up in the shop) worthless by shaving it down to nothing while watching the chips fly and thinking "Man, that is so cool!" as I smile at the tickle in my belly, the .002" of runout hasn't concerned me. I did make one of these

http://www.onagocag.com/jeffs.html

but that didn't require a whole lot of precision.

But, I do want to build rifles one day. I wan't to start out by rebarreling mu Rem. M7 to 7mm-08. As I become more proficient I'd like to blueprint the action of this rifle and my M700 '06.

So, my question is:
Is .002" of spindle runout too much for me to expect to do accurate rifle barrel/action work?

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Thrud
08-14-2003, 10:27 PM
mofugly13:
1) make sure the lathe is properly leveled first.
2) make sure everything is adjusted properly after leveling the machine.
3) check your chucks for slop & wear - this is the most likely source of your consternation.
4) lube it properly
5) Check the spindle bearings - they may need TLC/replacing.

turn a test piece between centers (not in the chuck) - the finishing cut should by very light.

Measure the piece with a micrometer. If it is consistant the entire length - your lathe is fine.

It should measure nearly the same when done with the tail center and the chuck - if it varies somewhat then your chuck is the source of the run out. Check the spindle bearings - they may need TLC/replacing.

Problems with the chuck can be as simple as loose mounting bolts or it just needs a proper cleaning and regreasing.

The backplate of the chuck must fit snuggly against the shoulder of the spindle (threaded spindle) as this is essential for low run-out (if it cannot screw down flat to it, the chuck will wobble).

The jaws can also be the source of error as can a stretched scroll. If it is a very old chuck get it repaired by a pro or buy a new unit. Bison makes quality chucks at a reasonable cost.

You can get your chucks repaired by http://www.worldwidechuck.com/

[This message has been edited by Thrud (edited 08-14-2003).]

mofugly13
08-14-2003, 10:55 PM
Thanks for the quick reply, Thrud. When I first got the lathe I used a 9" torpedo level to level it. Then, on this site I read about RDM. So, once I had my dial indicator, I did that. I was amazed at how just 1/16th of a turn on a levelling screw would affect the twist of the bed. Surpsisingly the 9" torpedo had me VERY close to true alignment. When I indicated the spindle, the first time I did it by indicating off the circumference of the more "accurate" of my three jaw chucks. Then I indicated off of a center I placed in the spindle, then off the outside of the spindle itself, and finally off the inner bore of the spindle (I was having mucho fun indicating everything I could think of with my new indicator). I have a L-00 mount spindle by the way with a 4MT bore. All of my measurements were .002". This surprised me because I thought the chuck would show more runout than the spindle itslef. I have kept the late lubed by making sure the numerous oil cups stay full. I should probably get the proper lube but I used Castrol Syntec motor oil when I first got it because that's what seemed like the best stuff to use out of all the different lubes I have in my shop. I will turn a test bar 'tween centers when I get my hands on a set of dogs, but lately other monetary priorities have popped up.

I know I omly have 6 posts on this board, but I've been lurking for about two years now and am amazed at the wealth of knowledge available from the guru's who post here. Thank's for the help...everyone.

Thrud
08-14-2003, 11:11 PM
If you are going to indicate off the chucks you should use a ground rod known to be striaght (Gauge pins work nicely and are less than $30). Clamp it in the jaws and indicate off of the ground piece. I use a ground carbide shank to do this on my machines.

It sounds like your bearings may need adjusting.

[This message has been edited by Thrud (edited 08-14-2003).]

shorty
08-15-2003, 11:20 PM
Hey Thrud,
I'm in the smoky Crowsnest Pass and I was wondering if you knew of any outfit that would come in and trouble shoot a lathe for a guy. I'm starting to get not bad at running it but the age and lack of maintanance it saw in the past have taken their toll on it. It's a good mahine, big too, and it would be nice to get back to snuff if possible.
Shorty

Thrud
08-16-2003, 02:03 AM
shorty:
My toolmaker friend is a few hundred miles from there - I will call him and ask if he is interested. What make and model is the lathe?

There are a few machine rebuilders in the province, but I do not know if they do acceptable work or not.

GM69camaro
08-17-2003, 01:19 PM
Mofugly,
That is a very interesting web page. Those fire pistons look really neat, sorta like a small 1 cylinder diesel engine. I might have to try to make one!

thanks,
Gordon

shorty
08-17-2003, 06:47 PM
Thrud,
It's an old Stanley, I'll have to check the model # monday. I'll also haveto see if the powers that be (bosses) would be interested in getting the old doll up to snuff.
Here's my email;
shortreeds@shaw.ca
if you're buddy or you want to get hold of me.
Thanx,