Sieg C6 Modifications

[Steve_Withnell]

Hi folks,

Just wanted to see if anyone had dealt with the tailstock on the Sieg C6? I've done the standard improvement of re-machining the clamp bolt and plate, but yesterday just discovered how much the upper casting wanders about as it swivels around the pin that controls the set-off.

I've done other mods to this machine from heavy duty to minor ones and if there is interest I will post the pics and notes etc.

PS:

AKA: MJ9526, Hafco MetalMaster AL-60, Grizzly G0516"

Schematic is here:

http://www.peter.com.au/metalwork/al-60-g0516-sieg-c6-m2/mj9526-manual.html#Tailstock

The pin I mentioned above is part 302 in the schematic. Though my base casting looks likes its been improved over this one slightly.

Steve

 

[gunboatbay]

Steve,
If you haven't already, you might want to address your question to one of the Yahoo lathe groups that seem somewhat oriented to the Sieg C6 lathe. I'd suggest trying the G0516 group first. It's not very active, but there are a lot of 'lurkers' there that have had the C6/Grizzly0516 for a number of years and might respond.

http://groups.yahoo.com/group/SiegM2andGrizzlyG0516/messages?o=1&yguid=324839999
http://finance.groups.yahoo.com/group/SIEG-SX3-C6B/messages

I agree with your comments about the sloppiness of the tailstock offset adjusting mechanism, but I haven't modified that aspect of my lathe. When I originally set up my lathe, it seemed to take me forever to adjust the tailstock offset by the trial & error method. I was so fed-up at that time that I locked it down probably tighter than I should have and it hasn't moved since. The occasional tapers that I've needed to turn have been short enough to be accomplished using the compound.

Art

 

[Steve_Withnell]

Thanks Art, I think I'm in the same place as you. I did look at the other group, but didn't find an answer. I have in mind to implement a gib strip and screws which should make the set off easier and more accurate, but I've so many real projects to get to it might be a while!

Steve

 

[steamer]

Something I noticed on the SB tailstock base.

The "tongue" was peened...on the rear facing side.,...just slightly...with a hammer.

I believe it was factory.

This made the tongue a tight fit in the groove of the tailstock housing.

I would want to check a few things before I went and did it on my lathe....but if it's sloppy....it won't sit still regardless

I would want to check the forward side of the groove to make sure it is square to the quil. Then I would want to make sure the forward side of the tongue was also square to the ways....or perhaps the headstock spindle.

If these surfaces are indeed true...you could upset...peen...the rear facing surface of the tongue slightly to tighten the fit in the groove.....

If I hadn't seen it with my own eyes I wouldn't have believed it either

Look close at the rear facing top corner of the tonque....on both sides.

Dave

 

[Blogwitch]

Dave,

On my old US made Atlas 10F, the main head casting was brought into alignment by judicial use of a cold chisel on it's what you call 'tongue' to kick it into correct alignment one way or another.

I had to repeat the exercise when I fitted a second hand taper bearing head instead of the plain bearing one. So it is a recognised 'realignment' or tightening up method.


John

 

[steamer]

Considering the design, which has no other option, and the requirement for low initial cost on SB or Atlas, there is really little other choice isn't there?

Some days I really miss my 10F John....she wasn't so bad.

I hesitated to state it as there is a large following of "Southbenders" here who have very high opinions....bordering on "mythical" status for the brand.....who may take my comments as casting aspersions....
But in reality....the SouthBend ...and the Atlas.... where both lathes built to a price point...like any other machine tool.

Dave

 

[pete]

Steve,
Before you start check all of the tailstocks alignments to the lathe bed, I no longer have my C-6 but the tailstock barrel pointed uphill .009 in 2". If there's anything out of alignment then now is the time to factor those in while reworking the tailstock. I can't quite figure out just how my lathe passed any quality control checks so I'd assume there isn't any. There's very little effect if the tailstock barrel is a few thou. high as long as it runs parrallel to the lathe ways and is aligned with the headstocks center of rotation. The way mine was, Trying to drill an accurate centerhole was a joke. Trying to drill and ream an accurate hole? I wouldn't even try it. One more tip, Your holding methods for sweeping the I.D. of the tailstock bore with a light weight DTI swung from the lathe chuck needs to be rock solid. You can be easily fooled with your measurements as it's amazing just how much a light weight DTI will flex a 1/4" diameter rod just due to the effects of gravity. I hope some of this helps.

Pete

 

[Steve_Withnell]

Thanks Pete, that's the second instance of a C6 tailstock "looking up" I've heard now. I've not measured mine yet in that plane yet, now I will get to it, thanks.

Steve

 

[pete]

Steve,
No problem,Hopefuly you'll still be willing to thank me after your checks. Accurate measureing tools sometimes tell you things that don't make your day. But I'd be interested in what you find.

Pete