Adjusting slides, how often?

[I. Klemetti]

How often do you guys adjust slides and gibs on your lathes?

I have got a Proxxon PD 230 with a milling unit. I think I have to make some adjustments after every 20 h of machining. Is this normal or do I have a low quality machinery? Or am I just picky?

I'm trying to have all sliding parts well oiled all the time.

-ilkka-

 

[narrowgauger]

Firstly check of the locknuts on the gib adjustment screws are in place. If not use minute amount of Locktite green thread locker on the adjustment screws. Gibs must be adjusted with the cross slide in the central (neutral) position.

I suspect from your question that you may be refering to the diecast compound slide, not the cross slide. If that is the case do your self a favour and remove it from the cross slide and only use it when absolutely necessary for taper work. This diecast unit is not well designed and is only suited for occasional work. If used constantly it will certainly work loose and create other problems as well. If you remove the Proxxon compound it is easy with a small rasing block to attach a A2Z QCTP, which will also help significantly with any gib problems since it resolves vibration / schatter problems.

the standard Proxxon 230 gibs are steel. whilst of good quality we have found that brass replacements reduced considerably the need to adjust the gibs once correctly set. we have 2 Proxxon 230's and 1 Toyo 210 (the Proxxon forerunner) in dayly use with brass gibs which are adjusted once every 6 months.

Proxxon quality is excellent compared to all other brands of small lathes.

have fun
Bernard

 

[rake60]

It depends on what I'm doing.

If I'm making a fan shaft for a local green house or pins for an industrial fork lift,
I don't check them at all. If it's cutting straight and clean enough to be within
factory specs tolerance, it's good.

If it's for me the rules change.
I may be the toughest inspector I've ever worked for.

Within tolerance isn't good enough. That is when the gib adjustment's come into play.
I want to hit the size and make it pretty the first time.

I'm 50 years old and I don't have to take off my shoes to count up how many times
all of those efforts were completely successful.

Craftsmanship is a practice.
I've worked with machinists who couldn't do anything right because the machine was garbage.

I've also worked with machinists who could run that same machine and turn out consistency
perfect results.

It is possible to set a machine up to perfection for today.
Tomorrow the ambient temperature, humidity, phase of the moon and power of "The Jedi Force"
will change.

Machine tools are strange animals.
If anyone ever comes up with a solid manual on the perfect way to handle their moods please
let me in on it.

Wives can't be that much different.
I'll pay to have it published and we'll both be millionaires!
:big:

Rick

 

[I. Klemetti]

Thank you for your opinions, guys.

Bernard, I was referring to all three slides (ways, cross slide and compound slide). I am using the compound slide for taper work only. The reason is that I noticed it is seldom parallel to the axis of rotation. The degree scale is too coarse to set it. Now you added another reason not to use the compound slide.

I have a milling unit on the lathe. Maybe the milling operations are shaking the slide adjustments. The cross slide is a relatively narrow unit for the milling table. I gotta be careful. A proper milling x-y-table is next on the purchase list.

Changing the gibs for a brass ones sounds a good idea. This is what I found on Youtube

[ame]http://www.youtube.com/watch?v=SadxxvUkAbg[/ame]

Although the author talks about cross slide he is referring to compound slide (or did I understand it right?). Anyhow, he talks for brass gibs.

-ilkka-

 

[narrowgauger]

Hi there

this guy is dealing with the compound slide. I do not agree with his methodology at all since one edge of the brass gib is in effect unsupported (except for the screw indent) which will cause the slide to lift under load. The original Proxxon gib is sound for an occasional use compound slide. Yes, it is too stiff, which is easily resolved by removing some material from the fixed gib, e.g. from the adjustment screw face.

as said earlier, the compound slide on the 230 is for occasional use only. Remove it for normal turning work and mount the toolpost direct on the cross slide with a suitable hight spacer block. this, together with the brass gibs will remove all play and will require minimal future adjustment. when machining the brass gibs place a steel insert between the brass gib and one adjustment screw to act as the lock screw. we do this by milling a slot about 15mm long into the gib (approximately 2mm deep) into which we place a small steel 15 x 2mm plate. This ensures that the gib is not bent when the cross slide is locked.

Bernard

 

[I. Klemetti]

Thank you again, Bernard

I think I'll change the gib for a brass one some day. My cross slide has got four screws: three ones with locknuts for adjusting and one for locking.

-ilkka-