Restoration/Repairs on a 10" LD Utilathe - Standard Modern

[Brent H]

Well this tapered gib for the compound was quite the project. Cast iron is a hard material. When you have a cutter that is a bit out of round - well it is harder to cut. Couple that with a sudden horrible back gear sound and things can get exciting! So after finding out my 30° end mill was out 0.0015” but being without options I slowed my feed and shifted to a slower mill speed. Then came the grinding sound that was not the bit cutting a hair out of round - it was the Bridgeport back gears growling away.

With everything set up and measurements on the money I proceeded to tear the head off the mill to access the back gears and see what was amiss. I found that the gears were not engaging fully with the main drive gear and also there was a need for more grease. After packing a half tube of grease Into the head I had one of my boys hold the main gear in position and set the lever up on the side. Then reassembled and started milling again in a much quieter environment.

I milled the blank to thickness and then used a 60° cutter setup (sort of a hodgepodge or cutter and holder) to cut the angle on the straight side of the gib.

once that side was done I set up with my jig for cutting the taper and just about screwed the whole thing up! I set the compound up and used it to turn my vice to the angle required for the gib. I used a test indicator to dial it in to 0.0000”. Total excitement and then it dawned on me that it would cut my angle opposite to what I needed - crap, what to do......my vice has the swivel base still on it so I set a dial indicator up at zero on one edge of the vice. I then moved the table over to the other side of the vice and swivelled the vice until my indicator came back to zero - sweet! I did a few other checks and things looked good!


roughed in the angle with a roughing mill and then cut the 30° bevel with my out of round cutter.

After milling I had several hours of scrapping and lapping and some grinding




Yep- the front of my compound is some chowdered up still, even after welding repairs - BUT!!!!!! The dang thing runs butter smooth now without end play !!! Yeh me!!! And my mill back gears are all set properly as well !!

 

[PeterT]

Nice work.

- does your lathe have a locking mechansim, like a glorified set screw that imparts force laterally onto the gib strip? My Taiwan 14x40 does & I think its a bad design feature. I modified mine with a angled brass shoe so the screw no longer gets a chance to make bite marks down the pristine gib strip. I might have some pics if this isnt clear

- I assume you have a surface grinder & scraping tools? <envy>

 

[Brent H]

Hey @PeterT, my gib is secured with an adjusting screw that holds it in position. No other screws so it has to fit the taper. One thing I noticed is that the new key that fits better has a slightly greater angle than the original - probably not the correct gib from the get go.

gib screw:
Surface grinder is getting a restoration and my scrapping tools - LOL - was a re-purposed carbide lathe tool that did a pretty good job! I was pretty careful with my set up on the mill and was out only maybe a thou or two from a good fit. After a few high spots were corrected things started working very well.
I smooth flattened the gib on my surface plate with a piece of wet 400 grit and some WD40. The mill marks only took a few figure 8’s to get rid of

 

[John Conroy]

Nice work Brent, gotta love it when you set out to fix one machine and wind up having to fix 2!

 

[Brent H]

@John Conroy - LOL - Yes indeed - it was the “feats of strength” to muscle off the mill motor and get things apart and back together. I had it apart last year when I first got it to fix a few things - there is a lot of grease in there for sure! It was originally missing the grease plate that keeps things from spraying everywhere - glad I replaced it - could have been one wicked mess.

 

[Marc Moreau]

@John Conroy - LOL - Yes indeed - it was the “feats of strength” to muscle off the mill motor and get things apart and back together. I had it apart last year when I first got it to fix a few things - there is a lot of grease in there for sure! It was originally missing the grease plate that keeps things from spraying everywhere - glad I replaced it - could have been one wicked mess.

Very nice pictures Thank You

 

[PeterT]

Hey @PeterT, my gib is secured with an adjusting screw that holds it in position. No other screws so it has to fit the taper.

Sorry, I mean a travel locking screw for cross slide, not a dovetail adjusting screw. Here is mine. And sketch of thingy I made. The wedge goes into the threaded hole & mates the dovetail angle. The steel bearing ball is between the wedge & thumbscrew end. So the screw now provides pure axial force & doesn't torque against the dovetail (which can actually make the carriage displace a couple thou by tightening as evidenced by DRO.

 

[Brent H]

Ah! @PeterT - no, I have nothing of the sort. On the drawings for the newer 11/13 Utilathe and on the bigger 12,14 and 16” LD Utilathe they have a cross feed stop. I gather this would be quite handy for threading - @David_R8 made/ has one for his type lathe.

What would you use the cross feed lock for?

 

[Kelly McLaughlin]

Nice resurrection! That poor thing was fairly hurt : (

 

[Brent H]

@Kelly McLaughlin , the lathe does have its challenges but I am just going over the top for repairs. Most people would just buy a new one - LOL making new gears will be soon

 

[PeterT]

What would you use the cross feed lock for?

Pretty much any time you want more accuracy and/or reducing load/wear on the leadscrew nut assembly. By independently clamping the table movement you are reducing float by providing a more secure backstop. Kind of like getting in the habit of clamping any non-motion mill axis when traversing. But a lathe its probably more important; the cutting load forces want to push back against the cross bed axis. in the same direction you are applying in-feed

 

[Brent H]

@PeterT - roger that, never really thought about that. Always made sure all components were on their load side of the thread - interesting ....

 

[Kelly McLaughlin]

Hi Brent! In the mid 90's a friend and I did a lot of side work for the shop I worked at. He had a 9 x 20 Utilathe like the one I currently have. we thought change gears for metric threading might be a good addition so I called Standard Modern. I don't recall the exact amount but I remember thinking yup 15 or 20 years we could make that back : ) I casually asked the fellow what that lathe was worth new he without hesitation told me 10,000.00. Keep fixing you have a lot of room for sweat equity : )

 

[Brent H]

Thanks @Kelly McLaughlin It pretty interesting making all these things and exploring the machining world outside of the comfort zone (at times - LOL).

I have plans to make the metric change gear assembly and the cutters etc. It will happen at some point - LOL.

next for the lathe is the cross feed screw and then a bunch of gears in the back. - I should have measured more when I first had it apart!! Ugh!

 

[Brent H]

Well, loads of disappointment and failure today....... lots of blessings and Gesundheitas going on and a few WTF’s.......

@David_R8 is super excited about his single point threading so I thought I would set up a pictorial on inside ACME threading for him and things were going well:


sharpen bit to 29° as per ACME threading gauge


fit to appropriate thread pitch (8 in my case)


Compound at 14°


Tool cutting just at centre - remember to grind in a lot of relief to allow the top profile of the cutter to do its work without the bottom parts dragging.

Cutter is square to the work and good to go.

Zero in your dials - be sure to have the load taken up so back lash is not an issue.


Lathe set up for 8 TPI - I am making a left hand internal thread so the part will turn in reverse with the feed still straight - so feed select is in reverse to counteract the chuck rotation.

ACME depth of cut calculations - basically pitch is 8 TPI or 0.125 divided by 2 plus ten thou. Or about 0.0725 ish.


Test cut at 0.005 and going well. Takes practice to get in the Rhythm to back out and release the half nuts at the right moment.
All was going according to my evil plan until the last few cuts. I was playing safe and only going a couple thousand at a time ...... seemed my apron handle was sometimes pausing and things did not sound as sweet..... then came the bang stop - blessings- a wee WTF panic dance, some rage and then containment....... alas...... a gear (brass one) that I had repaired near the beginning of lathe restoration has decided to leave this world. I am not sure if just the insert I made parted or if something bigger happened. I do know that the lathe still runs and feeds in the higher thread range. My 1-8 tpi bushing repair for the Cincinnati is fit for the bin after the last couple passes at what might be 8.3462894747420 TPI - Argh!!!

The anguish....... anyway, will be draining oil and measuring for a new gear tomorrow.

I still have the finer feeds so after making sure the offending gear is clear of destruction I will get things back to running and then machine a bunch of gear blanks to get machined on the mill.

the joys of success and the agony of my feet - shower time......

 

[DavidR8]

Well, loads of disappointment and failure today....... lots of blessings and Gesundheitas going on and a few WTF’s.......

@David_R8 is super excited about his single point threading so I thought I would set up a pictorial on inside ACME threading for him and things were going well:

View attachment 8567
sharpen bit to 29° as per ACME threading gauge

View attachment 8568
fit to appropriate thread pitch (8 in my case)

View attachment 8569
Compound at 14°

View attachment 8570
Tool cutting just at centre - remember to grind in a lot of relief to allow the top profile of the cutter to do its work without the bottom parts dragging.
View attachment 8571
Cutter is square to the work and good to go.
View attachment 8577
Zero in your dials - be sure to have the load taken up so back lash is not an issue.

View attachment 8578
Lathe set up for 8 TPI - I am making a left hand internal thread so the part will turn in reverse with the feed still straight - so feed select is in reverse to counteract the chuck rotation.
View attachment 8579
ACME depth of cut calculations - basically pitch is 8 TPI or 0.125 divided by 2 plus ten thou. Or about 0.0725 ish.

View attachment 8580
Test cut at 0.005 and going well. Takes practice to get in the Rhythm to back out and release the half nuts at the right moment.
All was going according to my evil plan until the last few cuts. I was playing safe and only going a couple thousand at a time ...... seemed my apron handle was sometimes pausing and things did not sound as sweet..... then came the bang stop - blessings- a wee WTF panic dance, some rage and then containment....... alas...... a gear (brass one) that I had repaired near the beginning of lathe restoration has decided to leave this world. I am not sure if just the insert I made parted or if something bigger happened. I do know that the lathe still runs and feeds in the higher thread range. My 1-8 tpi bushing repair for the Cincinnati is fit for the bin after the last couple passes at what might be 8.3462894747420 TPI - Argh!!!

The anguish....... anyway, will be draining oil and measuring for a new gear tomorrow.

I still have the finer feeds so after making sure the offending gear is clear of destruction I will get things back to running and then machine a bunch of gear blanks to get machined on the mill.

the joys of success and the agony of my feet - shower time......

Thanks for posting this @Brent H I really appreciate the pictures and setup.
Totally sucks about your gear grenading!


Sent from my iPhone using Tapatalk

 

[Brent H]

No problem @David_R8 - so close to a “here ya go mate, works like a charm.....” I will see what tomorrow brings - if things just let go but did not disintegrate I may be able to TIG it back together and carry on. I am without more stock though so things will have to pause on the acme bushing.

 

[Marc Moreau]

Thank you for the beautiful pictures , for my case this is the way I understand more. I learn this way.

 

[YYCHM]

So, what kind of road rash is going on with this piece of stock??? Looks like it's been spun out in the chuck and I don't know what. What is it? Brass?

Craig

 

[eotrfish]

Looks like it could be SAE660 Rotocast bearing bronze. The bars and/or tubes are cast oversize. The surface finish you show is normal, in fact I've seen much rougher surface than the one you've shown. The stuff I've gotten from McMaster-Carr lately has a much nicer finish but is still a little out of round, roughish and oversize. And yes it looks like it has been spun in a chuck. This stuff has a tendency to spin in the chuck because of uneven surface finish unless you really crank down on the chuck key. It all gets better once you've skimmed the surface nasties.