At what point is a lathe bed too far gone?

Yeah i`ll check around and see what I can find - $500 budget wouldnt be too bad.

As someone above said, the machine is still useable ... if i snug up the gib on the front side it has a range of about 4-5 " before it tightens up too much to be useable ... so I was able to make a 2 collar test at about .0005"

We shall see how bad it is once I remove those shims that someone added ...
 
Replaceable wear strips on the saddle? Am I see that right?
Have you indicated the bed ways?
I wonder if the slop is in the carriage/saddle...
 
Replaceable wear strips on the saddle? Am I see that right?
Have you indicated the bed ways?
I wonder if the slop is in the carriage/saddle...


Those strips are not factory, someone added them to try to deal with wear - there is wear both in the bed and the carriage.

The rear bed way thickness varies by .010" and I have not fully measured the front V way yet but it seems to drop about .015" overall.

The strips you see there are about 1 /16th thick and are just standard mild steel.
 
After removing those strips from the saddle and shimming down the rack so it would engage again, the wear on the bed is about .018" in in the 18" or so closest to the headstock.

I also found that the rear "gib" has been replaced with a plain steel bar, and the front gib/tightening bar only has one working bolt hole.

Is it acceptable to replace the rear bar with brass until I can find some cast iron?

I basically just want to get things working normally so I can take some test cuts and see if this is all livable or not.
 
For what you need to do, sure. Be certain that you have the adjusting screws properly seated in their holes or slots, then tighten the screws so as to lock up the crriage, loosen and repeat. Then loosen and adjust properly. Do this up in the worn area of course.
 
Alright got it all adjusted, had to take .030 off the front gib and was able to get it to lock down pretty good with about 6-8" of travel. Chatters like crazy now of course but see the next pic where the carriage is riding in the groove, lol. I can likely mock that thing up on the mill and get it closer, the v groove on the carriage is also quite worn, wider on the headstock end of course.

IMG_20181129_115421343.jpg

IMG_20181129_115432589.jpg

IMG_20181129_162055647.jpg
 
Ultimately I think I need to decide if its too far gone ... even if I were to Turcite and get the carriage in good shape, is .018" of drop in the bed too much to live with?

I did call around and noone in the pacific northwest knows of a surface grinder larger than 36".

If I can find another machine for my day to day use I may bring this one home and work on it over time ... unless there is a big demand for parts, then away it goes.
 
We hobby machinists often have a hard time letting go of machines. Me, too. When the reality is that the machine is worn out without time and effort well above what the machine could ever repay, we need to find a way to find a new hot date, get excited about it, and then move the old one on to a new sucker, er, I mean someone who will "love it just like it is." There are real sentimental reasons to keep some machines, but most of the time it is just stubbornness. We need to learn to happily be rid of the albatross around our neck...
 
Your lathe may be too far gone for a simple rebuild. but... It is fairly common to grind the ways in 2 setups, and blending them on a 24" grinder for a 36" bed - but it doubles the setup time, which is 70% of the cost. Your carriage would have to be reground and Turcite applied. It also means that at the tailstock the ways will be out a little (in the order of single digit thous).

Send a PM to Richard Smith here in the forum for his professional opinion. He is the real expert on this sort of restoration.
 
It is too far gone when it will not make parts that meet your specifications.
If the wear makes tapered or barrel shaped parts you can't live with, then get rid of it.
If you can make parts that work for you, USE IT.
 
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