9" SM Utilathe Restoration

[YotaBota]

Ref the belt tensioner - mine must be home made as well, it works okay but it just looks a bit rough for a factory build. The front slot holds the motor in tension and the rear slots holds motor up keeping the tension off the belt to change speeds. A bonus here is I can use the rear slot to take the tension off the belt when I'm done for the day (week,,,month).

 

[YYCHM]

Ref the belt tensioner - mine must be home made as well, it works okay but it just looks a bit rough for a factory build. The front slot holds the motor in tension and the rear slots holds motor up keeping the tension off the belt to change speeds. A bonus here is I can use the rear slot to take the tension off the belt when I'm done for the day (week,,,month).

You have the exact same arrangement my machine came with even the elongated handle (which I thought was home made). I liked being able to prop the motor up, however, the range of motion never allowed the tension notch to be used. Do you have the belt/gear cover for your machine? I had to switch to the short handle in order to close the belt/gear cover.

 

[YotaBota]

I still have the belt guard in place, with belt tensioned the guard closes. When I'm done for the day I just take the belt off and let the motor down so the guard will close and not hit the handle.
The ball maker is something else on my roundtoit list, yours looks good.

 

[YYCHM]

My reverse lockout solution LOL.

 

[YYCHM]

UH-OH...…. Looks like my tail stock spindle is toast



Here is a capture of the MT2 bore, it's in rough shape. I pulled all sorts of metal fragments out of there when I cleaned her up.

No wonder my tail stock chucks were wandering all over the place, hard to remove and the arbours scored.

Brent, do you think your MT2 reamer can save this?

Craig

 

[Dabbler]

It might need boring first. It will save the reamer from having to cut too much.

 

[Brent H]

Sounds like a call from the doctor is in order. I will let you know and arrange an appointment time.

 

[YotaBota]

Amazon has coarse/fine reamer sets for $12 and up. Not to cut in on the doctors house call out fee but, you could always get the set and then rent them out.

 

[Brent H]

 

[historicalarms]

This really does fall under a "farmers fix" definition but I did read it somewhere in either a Brownells gunsmithing kinks book or one of the Guy Letard shop story books.

a fellow had the same chewed up internal morse taper tailstock as your appears to be Craig. He claimed that he mixed up a batch of "Liquid Steel" epoxy and gooped up the tailstock with it then coated a new morse taper stub with release agent and inserted it snugly into the tailstock, let it set for the specified time and then just tapped it out with a long bar .

I guess it worked good enough to garner a 'write-up" but I would wonder how straight the new taper is compared to the axis of the machine as it kind of uses the old chewed up seat as a "line-up". He might have just got lucky with a "one-off" but you might also...your only out a small tube of liquid steel and if it doesn't work it can be just bored out with the reamer you need to buy if it doesn't work.

 

[historicalarms]

Just was finishing my morning coffee and started to think about the above...ya I know its dangerous for a hobby machinist & a farmer to think with the same mind...but anyhow I hit the "mix" button and this turd fell out of the "finished" chute.

To circumvent a bit of the "alignment" issues I thought it would be a good idea to install a shaft with a "known center" cut in the end in the headstock chuck...now after the goop-up of the socket I would use a dead center as a stub and inset it into the socket. Now, firmly, run that dead center point up into the shaft center in the chuck and let it sit that way while the epoxy set up...this should align the new socket perfectly with the lathe axis....in theory anyways...I think it would be an "in a pinch" fix for a "low horsepower" machine such as we use.

 

[Dabbler]

woah! the epoxy thing should only be a VERY last resort, just prior to making your own drawtube for the tailstock!
--it is impossible to align the newly minted hole to anything like accurately in line to the bore.

With that much material to take out, just reaming it won't make the hole concentric or aligned. it has to be removed, chucked up in a 4-jaw, accurately bored then reamed.

The gun guys have somehow promulgated the myth that a reamer is a cutting tool. (ref: via chamber reamers). this has never been true - but some guy guys don't mind working with dull tools and have misaligned chambers. Even a chamber should be bored first then finish reamed.

Even coarse/fine reamers are finish tools. You cannot properly cut the hole to be true with them. As a temporary fix while making a new drawtube, yes it will be sort of close, but never to tenths.

 

[Johnwa]

I have a reamer if you want to try it. The existing socket should be aligned reasonably well even with the scoring. The reamer should follow it fairly well.


Sent from my iPad using Tapatalk

 

[YYCHM]

I have a reamer if you want to try it. The existing socket should be aligned reasonably well even with the scoring. The reamer should follow it fairly well.


Sent from my iPad using Tapatalk

Hey John, I'll take you up on that offer thanks. PM sent.

Craig

 

[YotaBota]

I guess it all depends on how close to perfect you need/want to be. You might get away with chucking the quill and mounting a reamer in a boring bar holder and then be slow with lots of lube. The Y and Z axis would need to be sooooooooo close to perfect to have it work well. And if the homespun method doesn't work there's always the machine shop.

 

[Tom Kitta]

https://www.americanmachinist.com/m...l-applications-chapter-11-reaming-and-tapping

The problem is abuse - i.e. cutting too much with a reamer - "Therefore, reamers should not be used for heavy stock removal.". However, cutting too little with a reamer may lead to rubbing which is also bad - reamer has to cut! Note that you cannot be slow - recommendation is for 200 - 300% feed of drilling but not more otherwise you risk rubbing.

Also I wonder whatever tail-stock tube would be hardened metal - I would check first.

 

[Brent H]

Hey YYC - I made a new tailstock spindle for my lathe. It was not that bad of a job. It takes a but of time and such but not impossible.
I can check my old spindle and see what material it was - it might be cast iron. I made the new one out of 4140 - might be overkill.
machined it came out to less than 0.0001 over the 7” length and I drilled and tapered for the #2 morse and reamed the final clean up. The left hand acme thread - well - you can thread it like I did or you can machine an insert out of brass or steel or you can chop off your old spindle thread part, machine it and pressfit it into the new spindle.

I was just checking my setup today and I am zero across 10” of a test bar, so that is good. Line boring your tailstock —- longer topic

 

[historicalarms]

Well Craig you opened up a big box of worms with this one hey LOL

I do mostly agree with Dabbler on the reamer thing but will add that a million usable chambers are plain cut with chamber reamers for every one that is first bored to a starting stage (other than the rifling boring done on every blank). Sometimes a chambered barrel will show up that is beyond use (reamer chatter marks or an egg shaped, oblong chamber opening is most common) but for the most part comercial production chambering is "usable" by everyone other than the most discernible shooter trying to excel in a type F competition .

I have been lucky in all my chambering, in 25 or more chambers cut I haven't had a failure or even a slight issue show up. I have cut both stainless & 4140 C.M. barrel steel and have use both a "floating reamer holder" & a solid set-up...I like the solid better but both work satisfactory. My theory is that the reamer pilot & it's fit to the bore has as much to do with success as anything. I order any reamers I need with a "live pilot" that is easily changed to on that fits a particular barrel "perfectly"... not an easy loose fit nor a tight fit...it cant bind at all nor can it allow any movement that will turn into a chatter. It also becomes very plain very quickly that quick ins and outs of the reamer for cleaning is essential (don't forget to swab the bore every cleaning episode as well).

Back to Craig's repair with Johns reamer. I'm not sure how I would attack this, both ways I can come up with will have potential for failure...even more-so than my proposed "farmer fix" LOL.

Does the reamer have a pilot of any sort at the small dia. ? My first thought was to chuck the reamer up in a 4 jaw and then feed the tailstock barrel into it using its own drawbar but I can visualize enough radial cut pressure to cause the fed barrel to flex a bit...this will result in an oblong chamber cut I think .

The other option I thought of would be to chuck the tailstock barrel in a 4 jaw and mount the reamer in a floating set-up mounted to the cross-slide. This would absolutely require a pilot of some sort at the small end of the reamer otherwise chatter at either end would ruin the tailstock barrel.

A solid reamer set-up could be fashioned on the cross slide as well but centering & angles would have to be perfect in every direction or again a miss-shaped hole will result.

That Farmer fix might not be the most logical in most minds but I have seen some very expensive equipment put back into production for the rest of the season with some very unorthodox "repairs".

 

[YYCHM]

Also I wonder whatever tail-stock tube would be hardened metal - I would check first.

My file test indicates that it isn't hardened.

What's a roughing reamer for as compared to a fine reamer? I see they sell them as sets.

 

[YYCHM]

I'll throw this out there.....

Could attempting to ream make it worse than it already is?