Hi folks

I've just done an introductory thread over here: [ame="http://www.mycncuk.com/forums/showthread.php?p=8058#post8058"]New member from the IOM - MYCNCUK[/ame]

So I thought I would start one here to try and get help with a problem with my minilathe.

It's a Sieg C3 and the main problem I have is as follows.
I recently bought the Sieg DRO conversion for the lathe, and fitted it a few days ago.
It's a nice little setup, although it wasn't quite a straightforward fit as some of the bits didn't fit together out of the box!

That's all done now, but the big problem is a lot of play/backlash that has appeared since fitting them. NB - nothing I've 'adjusted' to get it to fit together would have been responsible for this.

Where it suffers most is on the cross slide. If I grip the cross slide and push the assembly above it (compound/toolpost etc) in & out (ie towards the back & front of the machine across the bed) it will move by something like 0.5-0.75mm! Surely there shouldn't be any play that you can feel by hand?

The compound also suffers from this but not quite as much. Still enough to be a nuisance and I would describe it as excessive even though I have nothing to compare it to.

I haven't tested the lathe on any project material since fitting these, but I'm guessing I'll get tons of tool chatter and will get horrible finish & be restricted to very shallow cuts etc as a result.
Before fitting the kit there was a little bit of play like this in the cross slide but a fraction of what is there now. Am very disappointed indeed at this stage but I'm hopeful that the problem can be resolved.

The gibs seem to be adjusted fairly well as both slides move quite freely without any significant wobble if you try to twist them by hand, so I'm not sure what else might influence the correct fit of this kit, ie what I can do to tighten it all up so it operates smoothly and rigidly.

All ideas gratefully received!

What other measures can I take to make the lathe as play/backlash free as possible? I already lapped the gibs to smooth the surfaces and that helped a little, and I've now bought some brass gibs (not yet fitted). Looking at them they seem to have one sharper edge and one more rounded edge (opposite side of the profile) to them so I'm uncertain which way round would be best.

I know I can also get better bearings for the lathe but I'm not sure how much difference they might make, or what else will make the most difference to its accuracy/rigidity.

Apologies if I've posted this in the wrong place, and I look forward to any useful suggestions you folks might be able to give me to sort out this problem.
I'm itching to get using it again but I suspect it will be horrible to use at present with these issues.

Cheers
Jim