Can An Atlas Bed Be Cut Down?

[yendor]

I have a 10F TH36 with some serious wear on the first 8-10" of the ways.
You can see the wear from standing 5' back. But the rest of the machine is in good condition.
It cuts a pretty nasty taper on a test bar.

I have access to a very good condition TH 54 Bed (for Free) that has very slight wear in the 1st 6" of the ways.
If I try hard I can make it catch a fingernail.

Is it feasible to cut off 18" from the TH54 bed and drill the required holes for the headstock mounting and feet?
If so I could have an excellent condition 36" bed with what would seem to be Zero wear.

Anybody ever done this?

 

[fgduncan]

STOP!!! Think about what you are proposing! Taking a longer bed and making it shorter? Having a bed that is too long is like having too much money in the bank. You may not need it, but if you do , it's there. Take that bed and put your headstock and tailstock on it and walk away with a (BIG) smile!

Besides, Looking at my 10F TH42, the bed has a reinforced, thicker area for the feet to be bolted to the bed. Cutting it off will remove the reinforcement and require some careful consideration about where to drill new holes and what size bolts to use.

Check with wa5cab, AKA Robert D. who is the resident guru on Atlas so see what he has to say.

 

[Andre]

I'd consider having it reground, if you can afford it. DO NOT CUT IT!

 

[pdentrem]

All you require is a longer leadscrew to finish the conversion. You could use the existing leadscrew by making an extension to the right hand end to make up the difference in length.
Pierre

 

[yendor]

Everybody slow down and don't type Caps. This is the internet and I can't Read Caps and louder than normal case.
NOTE: No lathes have been hurt in the process of creating this thread.
This is an exercise in "What-if", and "What are the options"

Re-Grind of the TH36 is an option I thought about. Here's what I found.
I have a quote for $800.00 but that is the bed only.
Note: This is a fairly local firm where I can drop off and deliver so no shipping. I would certainly need to go talk to someone there in person with pic's in hand to get what I believe would be a real price.
One other firm also local enough - responded with a; Yes, we can - send Pic's.
I sent pic's and got radio silence.
The quote doesn't include any work on the carriage saddle which also would require grinding the equal amount to raise the apron back to the original height and keep the leadscrew aligned.

Buy a 54" - Leadscrew - Yes I like the idea of a longer lathe - you never know.
I have seen other posts where replacement leadscrews were (at least 2 years ago) still available from Clausing over $800.00 ( I have yet to investigate this myself so can't confirm pricing)
I have seen posts that say 3/4" - 8 TPI Acme Thread Bar can be purchased and turned to fit.
The biggest issue I seen mentioned is cutting the Keyway for the Power Cross Feed.
Not sure I have the skills for this as yet. I'm just learning this lathe stuff.

So - let's help me sort out options:

What is the process of making a replacement leadscrew.
How involved is it?
Skill level required?
High, Med, Low ?
How would the steps for the process go.
What comes first?

The TH36 won't turn what I need the way it is - since it's way out of whack.
I'm guessing I could swap over the parts.
Run thru a thousand checks and alignments to get it all setup and manually move the carriage to cut a test bar and I suppose a new leadscrew - right?
But then the Keyway slot ?

 

[Holescreek]

Since Atlas ways are flat the simplest and most cost effective solution is to grind or scrape them back in. Since grinding has been quoted astronomically high you should consider learning how to scrape. And yes, even if you do, you're going to need to adjust some other parts to make it work but the only cost is your time scraping.

The unknown (at least to me) here is just how far out the bed really is. If it's .025~.035" it's doable. If it's 1/8" it's scrap iron. the distance in between is the gray area.

 

[kd4gij]

I have read severial threads where one has swapped the bed end for end. put the bad end at the tail stock end.

 

[Ulma Doctor]

It's probably not feasible to cut a TH54 bed down....
Grinding is way too expensive, you could buy another lathe for the cost.
then there is scraping... it will be time consuming but it's the most accurate method- even after being ground.
I'd consider swapping the TH54 bed and retrofitting the TH36 leadscrew until i could find a suitable TH54 leadscrew or a trashed out machine for cheap.
the conversion would look a little funny and you wouldn't get full travel until the TH54 leadscrew was obtained.
it's a viable solution if you don't need full length all the time.
another thing i would consider is how bad the saddle is, if it's worn as bad as the ways,
you'll be in for a lot of work to straighten it out...

 

[wa5cab]

I have a 10F TH36 with some serious wear on the first 8-10" of the ways.
You can see the wear from standing 5' back. But the rest of the machine is in good condition.
It cuts a pretty nasty taper on a test bar.

I have access to a very good condition TH 54 Bed (for Free) that has very slight wear in the 1st 6" of the ways.
If I try hard I can make it catch a fingernail.

Is it feasible to cut off 18" from the TH54 bed and drill the required holes for the headstock mounting and feet?
If so I could have an excellent condition 36" bed with what would seem to be Zero wear.

Anybody ever done this?

Sorry, I've been out of pocket for a bit, getting new teeth. I agree with most of the comments. My lathe is a 3996 so it doesn't have the same bed as the TH54 but from the description it is at least similar in that the bottom flange is wider at both ends where the legs attach. And at least if you have the room, the only theoretical advantage to a shorter bed is that it might be marginally stiffer. I would use the new bed as is. I've forgotten what stand you have (if any) but if is the factory original cast iron legs contemporary with the lathe, all that you would need would be the wood. Having a lathe longer than you usually need is not a disadvantage if you don't use the additional length like having a swing much larger than you need is.

The other part you would need is the rack, but it may still be on the stripped bed. If not, I think that the shorter rack should bolt up except for the right hand groove pin. As for the lead screw, I would start looking for a good used one and in the meantime (assuming you don't find one PDQ), drill and tap two holes for the lead screw support bearing and use the short one.

On the carriage, most of the uneven wear is going to be on the carriage gib, which is by far the easiest of the three on the carriage assembly to make a replacement for. You can get a pretty good idea of the wear on the carriage bearing areas that run on the top of the ways by first checking them for flatness. Then mount the carriage on the new bed with the original carriage hold down shims and use a feeler gauge set to determine the clearance underneath. The difference between front and rear will be a pretty good indicator of wear on the carriage bearing areas. And if push comes to shove, asking prices for carriages isn't generally very high because there isn't much demand for them. And the last three 3/8" ways 12" models use the same carriage as the 10F.

 

[shawn]

i have a bed from a 10'' 42.. its scraped and scaled nicely ... got a lathe and a whole bunch of parts in a trade. it was built into the entire lathe but i swapped everything back to the original bed that has about 6 thou droop in the middle. i plan on mountind it solid to a thick bench and blocking up the mid section just past true and hopefully in a few years, either it will be flat enough to correct or tll be so frustrated with the obstruction underneeth the bed ill just say screw it.... but the other bed is a craftsman badged.. 42.. if anyone is interested in it?