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View Full Version : Looking at a lathe that doesnt run.



donf
05-29-2012, 03:04 AM
I have been scrounging around looking for a bigger lathe. I found one candidate that might work or might be one to stay away from depending on what I find. A south bend 9" that was taken off its bench years ago and is missing some small parts. Other than looking for gouges in the bed and turning everything by hand, Is there any steps I should take to make sure its a keeper? I do have a long 36" mechanics straight edge if that will help? Its not a machinist one, but it has a ground edge that's supposed to be accurate enough for checking the aliment of heads and blocks, etc.
Thanks, Don

mike4
05-29-2012, 03:43 AM
I have been scrounging around looking for a bigger lathe. I found one candidate that might work or might be one to stay away from depending on what I find. A south bend 9" that was taken off its bench years ago and is missing some small parts. Other than looking for gouges in the bed and turning everything by hand, Is there any steps I should take to make sure its a keeper? I do have a long 36" mechanics straight edge if that will help? Its not a machinist one, but it has a ground edge that's supposed to be accurate enough for checking the aliment of heads and blocks, etc.
Thanks, Don
Look for wear on the bed under the chuck , if you can get to see one that is complete , try to get a cost of the missing parts, at least if it turns andyou have some mechanical skills it could be a good priject.
Michael

LKeithR
05-29-2012, 04:23 AM
All depends on what you're looking for, I suppose. If it's cheap and you've got the time to mess around it might be worth while. Me, I'd never touch it--something like that belongs in the scrap heap...

alanganes
05-29-2012, 06:27 AM
If you have not seen this already, read the info here:

http://www.mermac.com/

Good starting advice on how to quickly assess a machine from a guy who was in the business.

FYI

oldtiffie
05-29-2012, 08:03 AM
If the owner/seller could not arrange for the lathe to be operable and let me try it I'd give it a miss. I'd only need a single-phase machine and I have a very good portable "Honda" 2KW gen-set which should run that lathe easily.

But given that I pretty well always settle on new Chinese machines which are pretty cheap and not too bad that lathe up for sale would need to measure up. If there was too much unknown or if known too much spares and time and money involved in doing it up to an acceptable standard, I'd give it a miss there too.

A warranty is only worth the good will of the seller and the paper its written on - ie no written warranty = no warranty.

The buyer assumes lot of risk in buying used anything - lathes and other shop machines included - especially in an "as is - where is" sale.

justanengineer
05-29-2012, 08:41 AM
Take as many photos of it as possible and post them on this board, PM's SB forum, and a few others. I am always amazed by what some of the collectors can spot in a photo.

As far as missing parts are concerned, SB9s are one of the most commonly collected lathes today, so there are a ton of spare parts on ebay, craigs etc. Personally, if its missing anything common, it better be cheap, as in <$300 for a 9a if youre in the northeast or midwest. These lathes when complete dont bring much more than that.

donf
05-29-2012, 09:51 AM
Thank you for the advice. I will do my homework and take a look. I think it might be something I pass on, but you never know. :)

jep24601
05-29-2012, 10:44 AM
The "missing parts" may be the killer here. I recently got an Atlas 10" which had obviously been dropped when moving breaking the gear door, the gear banjo, the piece of the bed which the door hinge clamped to, the motor mount bracket, and it had sat for a while with a light surface rust and some parts slighly immobile BUT IT WAS COMPLETE. It is running fine now after I repaired the broken parts and scraped rust with a razor blade and lubed initially with penetrating oil and re-wired with new wiring, and I had to purchase NO parts - nil outlay in cost except for brazing and welding rods and socket screws and epoxy already in hand - just some time.

However, had I needed to buy parts this would have been a completely different story. People want $20 to $40 for zamac gear wheels even. With just a few parts missing your lathe is a parts lathe. A couple of parts only needed and maybe the lathe is worth a little.

Bill Pace
05-29-2012, 11:34 AM
I have bought several lathes and a couple mills in not working condition, having been sitting in a corner for years, and I can add some comments here.

As already mentioned, while parts for a SB are pretty plentiful, there just may be that one or two that arent available, or are so expensive as to make them unattainable. If you are pretty skilled you can make them.

Aside from parts, plan on a complete disassembly - it may not need it but more than likely will. Oil access points and their holes will be clogged with hardened oils and cannot be cleared without taking apart - while it may run and seem fine, if oil isnt getting to its destination... There will be dirt dauber nests, chip/shavings hidden in the most unusual places. Then theres the rust, it will be hidden in just as many places unseen as seen.

If you arent able to devote a good deal of time - and have some experience - to deal with these possible scenarios, then its best to wait on something that is in operation and can be checked better.

However, as I mentioned, I have done several of these old lathes and consider doing it as my 'hobby' I just get a kick out of tearing them down to the last screw/nut and bringing them back to something like their original condition. But it can take an awful lot of time, which I have, being retired

Dr Stan
05-29-2012, 11:54 AM
But given that I pretty well always settle on new Chinese machines which are pretty cheap

And you get exactly what you paid for. Plan on doing as much repair work on a Chinese import as you would a 50+ year old machine.

Since you are a mechanic and if you have the time and inclination I say pay scrap price for the machine and as others have said plan to do a complete tear down so you can get the lubrication system up to snuf.

In the final analysis you are the one making the decision. So if you have more time than money I recommend saving this piece of old iron from the scrapper.

Just my $0.02 worth.

DR
05-29-2012, 03:00 PM
I'm no exert on SB's, but I would check the spindle bearings. All the 9", AFAIK, are plain bearing (as opposed to roller or ball bearing). That should be a major concern IMO. I would be more worried about the spindle than bed wear.

I've seen older SB's with spindle running in cast iron "bearings". Some like that, when badly worn would be near impossible is to easily rebuild.

A good way to check spindle bearings might be to pry up on the spindle with a piece of wood and note deflection with a dial indicator.

Alistair Hosie
05-29-2012, 03:13 PM
Check condition,price i.e cost of missing parts,hassle and availability of tracking and buying and having the parts delivered in good condition missing parts might not be in great condition if you buy them blind ,original cost of this lathe compared with a good condition and running example then sit down and do your homework unless your saving a substantial sum I would wait till something better comes along. MY 2 cents. Alistair

dian
05-29-2012, 03:14 PM
if they are plain bearings (which i dont know), be sure to check if the oil pump is pumping oil. mine wasnt.

donf
05-29-2012, 09:00 PM
Thank you for the advise, I have decided to pass on the deal and keep looking. It was almost the same price as others that did power up, but were many hours drive. It sounds like if I'm going to put in that much work and money into something I would be better off starting with something a little larger too so I don't have to upgrade again in the future.

donf
06-13-2012, 01:28 PM
http://i228.photobucket.com/albums/ee288/earlysb1/Shop/4e34d498.jpg
After a few weeks search I followed some of the advice given here and broke a good many rules too according to the paper linked in the first few posts. I did a 12hr dash to the Columbia river yesterday and gave $500 for this ($700 if you count my fuel too!)
It doesn't run and was not under power (3phase) but the bed ways are very good with no digs and it appears to be a much later machine than all the worn out 40's and 50's lathes I was finding locally. It came with six change gears and there is a 3/4 of an identical machine for some parts if I hurry and find anything else I need.
The two items that were missing from both machines were the left cabinet door and the cross slide handle is bent on this machine and missing from the other.
I got an extra electrical panel with the missing switches, and was wondering if any one knew what the red toe kicker switch at the base of the cabinet was?

oil mac
06-13-2012, 01:48 PM
Boxford CUD lathe is a good little machine, with roller bearings, I think you got a basically fair deal, The red bar is an automatic toe operated safety cut out , This little machine might have come from a training establishment

Dr Stan
06-13-2012, 02:35 PM
Boxford CUD lathe is a good little machine, with roller bearings, I think you got a basically fair deal, The red bar is an automatic toe operated safety cut out , This little machine might have come from a training establishment

Ditto. The Boxford lathes were well made. You may want to check with some of the members from across the pond to see if they know of sources for parts if necessary. If you did not get the manual I'd check on-line and if not available check with Tony at lathes.uk/

BTW, very good find.

On edit, since the cross feed handle is bent, I'd check to make sure the cross feed screw is OK. Also if you do not want to deal with a phase converter that machine should be easy to swap out the motor for a single phase unit.

donf
06-13-2012, 06:16 PM
Thank you for the information. :) Yes I think it must have been some type of school lathe. I found an adjustable rod on the back of the lathe that will shut the spindle off if the cross slide gets too close to the chuck. There is also some type of yellow chuck guard that was included in the parts.

I looked at the cross slide screw and its is slightly bent too, right at the end.

So far it looks OK though as a project mostly cleaning and repainting related. The cross slide handle and screw are the only big things I have found with a closer look.

donf
06-14-2012, 12:01 AM
Is a phase converter the best way to get the lathe up and running?
The items that have to be powered up are the coolant pump, a light on the back splash, and the Brook Compton Parkinson Motor 550w, 1425 RPM, 346v@1.75a or 200v@3 amps.

I seriously don't care about VFD - it only takes a second to switch belt pulleys and 40-1450rpm is a plenty of range for me. The wiring is unbelievably complicated on the back of the control panel, but a lot of the mess is from all the different safety and stop switches on the machine. A lot of those will not used. Simple and reliable is my goal.

I did a search at the Boxford Yahoo group, but with any yahoo group the search feature is by individual messages. I did find some very helpful files though about converting the coolant pump and light over to 220v single phase

If a complete electrics swap to single phase power with a new motor, switches and pump light is a better way to do it then that's fine too. I want to do it once and I want to do it right.

I did find a book recommendation from Lathes.UK?
http://www.ebay.com/itm/160804560516?_trksid=p5197.c0.m619

Dr Stan
06-14-2012, 12:37 AM
Those are some odd voltages. Can you check with the seller to find out if it was wired to 220 V 3 phase?

I would not dismiss all the safety stops & switches, especially the foot brake. I've used them on occasion and they are quite helpful in preventing a serious wreck.

donf
06-14-2012, 12:49 AM
Thank you for the reply
That motor is standard on the Boxford, its specs are all over the Boxford yahoo site. The seller of my lathe bought the lathes as a group at auction several years ago. He sold all the rest and was saving this last one for himself, but its a big job to get it up and running again. I can take a picture of the motor plate, but it says the same thing. I'm keeping the emergency stop. What I was talking about is there is a cut out switch if the chuck cover is up, a cut out switch if the gear box door is open, a cut out switch if the pulley door in the cabinet is open. There is an adjustable cutout switch in case the crossfeed gets too close to the chuck too, but I'm going to keep that one.

IanPendle
06-14-2012, 06:28 AM
Don,

I used to have a Boxford ex-training establishment. It had safety cut-out switches all over the place. The hardest to find was one located in the backgear change handle assembly - a little screw you had to tighten back each time you changed to or from backgear. I suppose it was to stop trainees shifting to backgear with the machine running. It took a lot of looking, and considerable bad language, to figure out why my motor wouldn't start!

Ian.

Abaker
06-14-2012, 09:18 AM
If you rule out the VFD (I wouldn't because variable speed is really nice) then you can either go completely single phase or add a rotary phase converter. Avoid the static "phase converter" they are just motor starters and the motor is de-rated to 2/3 it's output.

If it were me I'd go three phase because the motors seem to be better/smoother than single phase. Plus once you get a phase converter then your tool acquisition horizons will open up. You can snag that nice mill that everyone else passes up because it's not single phase.

RPCs are fairly simple to make - they are basically just a three phase motor sized about 150% of the load motor wired into the same circuit. The trick is starting the idler motor. My current method is the sudden discharge linear to rotary power converter. AKA Wrap a rope around the idler motor shaft and yank.

I read and re-read this thread from PM.
http://www.practicalmachinist.com/vb/transformers-phase-converters-vfd/rotary-phase-converter-designs-plans-101231/

If you buy it or make the RPC, be sure that any 115V loads wired off it are wired to one of the hots coming in from the mains. The voltage between the generated leg and neutral is 250V. I found this out the hard way when I fried a 115V coil on a contactor by wiring it to the generated leg.

donf
06-14-2012, 10:48 AM
Thank you for the information! I did find that 380v is European three phase voltage, but since the motor is also rated at 200v then I think it will be fine.

So from the feed back I think the first step is to take the motor out of the cabinet and down to a local motor shop for testing and a look over. No use adapting anything if the motor is inop or badly worn!
If the motor is in good shape then it sounds like that the 3 phase motors are smoother and more compact so I will contact Boxford and see about getting the proper diagrams for my lathe in single phase and three phase and proceed from there.