Taig lathe, help a nub

[Speedygonzales]

okay so I am not sure if the previous owner lapped the carriage to the bed.
and I am trying to make sure everything is ready for its first cuts.

what is the proper way of adjusting the gibs on the carriage?
should you be able to push the carriage across the the bed by hand?

also the backlash in the handles of the carriage and cross slide is this normal to have?

I did read taigs manual but it didn't talk much about this (unless I dont have the right manual?

thanks!

Michael
(I am a super nub! please help)

[noisillator]

In case you haven't seen this, here's the link to Nick Carter's setup instructions:

http://www.cartertools.com/setup.html

I don't think you can hurt the lathe by lapping it, even if the previous owner already did so. Mine is still new in the box - the "assembled" version - and I can tell you the carriage is somewhat difficult to slide by hand. It's really tight to the bed, and there's no perceptible side play. The feed and crosslide knobs both have backlash, so I don't think you have anything to worry about.

[Speedygonzales]

thanks noisillator!
just what I needed

[Jeff-Birt]

The two very important points when lapping are:

1) Don't get carried away, it is a 15 minute process, not 1 hour.
2) Be doubly sure to clean all the lapping compound off there or you will continue to wear down the aluminum.

The 'tightness' of the carriage is a function of how tight the gib is. You only need it tight enough to remove any slop. Having it tighter just makes it wear more quickly. However, I find I like to adjust mine to provide some resistance to turning the feed handle; it also keep the carriage from want to walk on its own due to vibration.

[escott76]

Originally Posted by noisillator I don't think you can hurt the lathe by lapping it, even if the previous owner already did so.

No, you CAN hurt the lathe by doing this. Removing metal in this fashion is NOT going to make 2 flat and parallel surfaces.
Lets say one of the surfaces is "flat" to start, and one is bowed, like this |( . When you are done "lapping" you will have two surfaces like this (( , as the center of the bowed part will wear down with abrasive into the other part, as the other edges don't make contact.
There are several posts describing this here on the zone. I am aware that many people still do this to their machines.
Regardless of if you believe that it will make things flat or not, it still has the capacity to damage the ways, either by causing uneven wear on the bed, or by accelerating wear by leaving grit embedded in the surface.

[noisillator]

Originally Posted by escott76 No, you CAN hurt the lathe by doing this.

Not if it's done properly, i.e. not to excess.

it still has the capacity to damage the ways ... by accelerating wear by leaving grit embedded in the surface.

I don't think I suggested that he do that.

[Speedygonzales]

I got in contact with the previous owner and he told me that since he didnt use the metal carriage he didnt lap it.

so it shouldn't be a problem if I do it?
after all the cartertools gives instructions to do so and the manual also.

do you guys think lagostina cleaner would be fine?
http://www.lagostina.ca/eng/prodaccecleaner.html

and I would clean it up after

[escott76]

Originally Posted by noisillator Not if it's done properly, i.e. not to excess. I don't think I suggested that he do that.

You can do what you like to your own tools, that doesn't mean it's "proper". I'll say it again, taking two non-flat surfaces (of different hardnesses, and lengths mind you) and rubbing them together with abrasive in between does not produce a pair of flat surfaces.
You may not have SUGGESTED he do that, but tell me, how is it that you are sure you've removed all the grit?

[Speedygonzales]

Originally Posted by escott76 You can do what you like to your own tools, that doesn't mean it's "proper". I'll say it again, taking two non-flat surfaces (of different hardnesses, and lengths mind you) and rubbing them together with abrasive in between does not produce a pair of flat surfaces. You may not have SUGGESTED he do that, but tell me, how is it that you are sure you've removed all the grit?

not blasting you in any way.
I understand what your saying, but why would Taig have this in their manual?
wouldnt Taig not put the lapping instruction in if it wasnt good for the lathe?

[escott76]

Originally Posted by Speedygonzales not blasting you in any way. I understand what your saying, but why would Taig have this in their manual? wouldnt Taig not put the lapping instruction in if it wasnt good for the lathe?

I don't recall it being in my TAIG lathe manual, but it was some time ago. It's your machine, do what you like. It certainly isn't needed to use the lathe, and hold tolerances.
Real lapping (this is not real lapping, which uses specially made tools to do the work) takes a while to learn to do properly, and a good, educated user to know when it's enough. It also takes tools which I'm guessing you don't have, like a reference surface of known flatness. Why on earth would you want the first operation you have with your new toy something that deliberately attempts to remove material from the surfaces that you rely on for the machine's precision, with no accurate way to measure the results of your attempt?
People like to come up with things that "seem" to help, but since they don't know any better, or lack the ability to measure the changes caused by their "upgrades" they never realize the harm they do. They get passed around and more people who are still learning pick them up. This is one of those things. Spend your time learning to grind tools, or just making chips. It will be far better spent.
I never even thought lapping the TAIG lathe I got nearly 10 years ago. Still works awesome, it will most likely get CNC'd later this year.

[noisillator]

Originally Posted by escott76 ... how is it that you are sure you've removed all the grit?

I watched myself do it.

[Jeff-Birt]

I don't recall it being in my TAIG lathe manual

If you buy the lathe 'kit' is most certainly in the instructions. The basic concept is just like lapping valves on older cars. It is a procedure that must be done on the kit lathes to get the best fit and smoothest operation of the carriage/cross slide. You do not use a commercial lapping compound though as the parts that are being lapped are aluminum.