[Newbie] Emco Compact 8 Repair

[slow-poke]

Hi all first time post here.

I’m a novice with machine tools so have come to learn.

This seemed like the most appropriate thread for this question as I could not find a category for Emco lathes.

I recently purchased an Emco Compact 8 lathe that needs what appears to be a minor repair.

Excuse me if I get some terminology incorrect. The Emco 8, that I purchased has a broken (missing) lever that engages the horizontal feed (see image below). However a complete new replacement part (Apron?) was included so I just need to replace the old with new.

It looks like I will have to remove the compound rest to get access to some of the bolts that retain the apron.

Can I simply unbolt the compound rest / cross slide from the apron or should I take any measurements or be aware of anything before I start disassembly?

Any and all advice is welcome.

 

[Bob Korves]

Welcome to Hobby-Machinist!
If I were doing the job, the first thing I would do is find a manual for the lathe containing a parts breakdown. Then you can see how it comes apart and goes back together. There may be one posted on this site. There are likely other Emco lathe owners on these forums who will also step up to help you. Emco is known for making quality lathes, congratulations!

 

[slow-poke]

Progress The new apron is in, I do have a few questions....

Note the feed lever operates a sort of C-Clamp that the feed screw passes through that gets smaller in diameter as you rotate the lever.

If I have the carriage any ware from about one inch and more away from the chuck the feed works, however when I get within about an inch of the chuck the carriage stops feeding (the lead screw keeps rotating, but the carriage just seems to disengage somehow), the lever does not seem to move so it's not clear what's causing the carriage to stop moving?), I'm not sure how to fix this, any ideas?

I'm wondering what this bolt "G" is for ?


I'm also not sure what this set screw "H" does?

 

[Bob Korves]

The clamp things are called "half nuts". They are used for threading, and also for longitudinal feeds on some lathes. If there is a separate feed, do not use the half nuts for feeding for turning. Bolt G probably locks the cross slide. I don't see a feed knob on the apron, but some have it on the headstock end. Once again, find a manual for the machine! Then RTFM (read the manual.) 8^)

 

[Ulma Doctor]

the leadscrew has provision for a handwheel on the tailstock end of the leadscrew.
there are 2 small flats on the leadscrew end for handwheel engagement.

as far as the half nut engagement with the leadscrew, move the carraige as far as you can to the tailstock end and inspect the leadscrew carefully
there may be considerable wear, or maybe a crash occured and part of the leadscrew thread may be compromised.
if the laedscrew is compromised or damaged, it could impart damage on the new/used parts intended to repair the condition.

 

[mikey]

I am attaching the Emco Compact 8 IPB.

There are two things that might help the half-nut issues:

• Look at the IPB on page 14. You will see 4 hex head screws that hold the half nuts to the apron. Loosen the two screws on the right and adjust the adjusting screw #9 in the IPB until the half nuts move freely but without play.
• "H" in your pic adjusts the backlash in the lead screw when the half nuts are engaged. Loosen the screw and engage the half nuts, then turn the screw until backlash is eliminated.

My friend has a Compact 8 that we just restored to like new condition. I can ask him to verify the above tomorrow. Here is his lathe:



His lathe started out looking just like yours. Now it runs tight, with no backlash in any screw. Nice little lathe!

 

[slow-poke]

I am attaching the Emco Compact 8 IPB.

There are two things that might help the half-nut issues:

• Look at the IPB on page 14. You will see 4 hex head screws that hold the half nuts to the apron. Loosen the two screws on the right and adjust the adjusting screw #9 in the IPB until the half nuts move freely but without play.
• "H" in your pic adjusts the backlash in the lead screw when the half nuts are engaged. Loosen the screw and engage the half nuts, then turn the screw until backlash is eliminated.

My friend has a Compact 8 that we just restored to like new condition. I can ask him to verify the above tomorrow. Here is his lathe:

View attachment 141105

His lathe started out looking just like yours. Now it runs tight, with no backlash in any screw. Nice little lathe!

Mikey, thanks for that, I adjusted the half-nut setscrews and the longitudinal feed now works.

I'm not sure if this adjustment is just finicky or there is some underlying problem:
1) With the two bolts on the RHS loosened if I adjust set screw 9 for just shy of tight lever action, when I tighten the two bolts I can no longer move the lever, so I had to adjust setscrew 9 iteratively while tightening the two bolts
2) There is a fair bit of backlash and adjusting setscrew 6 is quite finicky, I expected that if I continued to turn this setscrew clockwise the backlash would be reduced until at some point the longitudinal feed would become too tight, however that's not the case, too many turns clockwise and the feed no longer engages and same thing the other way, too many turns counter-clockwise and the feed no longer engages, these is a sweet spot that allows engagement, however it seems to have little effect on backlash. For the type of work I do this is not a problem , so I guess I will live with it, but would like to understand why it acts like it does.

I'm pretty happy with my new toy and now want to do some upgrades: quick change tool post (I like the look of the one in the restored image you provided), possibly variable speed control and possibly driven cross feed. Since I'm largely over the repair aspect I will start new threads on the other topics.

BTW I found the manual at Machinemanuals.co.uk, so I now have a manual.

Thanks to all that chimed in

 

[mikey]

You might want to adjust the back lash on the leadscrew itself, then re-adjust those other settings on the saddle. If you look at page 3 of the IPB, you will see that there is a lock nut and adjuster on the end of the RH leadscrew support. Disengage the half nuts and move the lead screw to see if there is play. If so, loosen the lock nut 7 and adjust the set screw 8 until play is eliminated. Then go back and check the other two adjustments you made to see if they can be done better.

Edit: called my friend and he said to adjust the lead screw as above, then adjust the half nuts.

 

[slow-poke]

Mike,

The lead-screw did have a fair bit of play, that adjustment helped

 

[Dr. Navycop]

Progress View attachment 186272 The new apron is in, I do have a few questions....
View attachment 141095
Note the feed lever operates a sort of C-Clamp that the feed screw passes through that gets smaller in diameter as you rotate the lever.

If I have the carriage any ware from about one inch and more away from the chuck the feed works, however when I get within about an inch of the chuck the carriage stops feeding (the lead screw keeps rotating, but the carriage just seems to disengage somehow), the lever does not seem to move so it's not clear what's causing the carriage to stop moving?), I'm not sure how to fix this, any ideas?

I'm wondering what this bolt "G" is for ?
View attachment 141096

I'm also not sure what this set screw "H" does?

I am attaching the Emco Compact 8 IPB.
There are two things that might help the half-nut issues:

• Look at the IPB on page 14. You will see 4 hex head screws that hold the half nuts to the apron. Loosen the two screws on the right and adjust the adjusting screw #9 in the IPB until the half nuts move freely but without play.
• "H" in your pic adjusts the backlash in the lead screw when the half nuts are engaged. Loosen the screw and engage the half nuts, then turn the screw until backlash is eliminated.

My friend has a Compact 8 that we just restored to like new condition. I can ask him to verify the above tomorrow. Here is his lathe:

View attachment 141105

His lathe started out looking just like yours. Now it runs tight, with no backlash in any screw. Nice little lathe!