# New Cromwell S800 MK3 Lathe



## valleyboy101 (Dec 12, 2013)

*New Cromwell S800 MK3 Lathe - 2 Pages Now*

Hi All,
In my previous posts New Lathe Thursday and New Lathe Thursday and Movin in Monday I posted some pictures of the new to me Cromwell S800 Mk3 which I purchased from the Canadian govt.  If asked a couple of weeks ago I would have said that I have a 13" Collchester Student and it's all the lathe I need.  True enough but when I saw this unusual precision lathe with tooling and read up on it, I knew it was a one time opportunity.
It has been home a week and I have the base cabinet cleaned, sanded and painted one coat.
The plan is to get a nice finish on the base and then install a sheet of heavy poly over the chip tray and set the lathe down on it.  That way when I'm cleaning and painting the lathe, the poly should save the newly painted chip tray from getting scarred up by solvent etc.
I had the paint store mix up some paint to match a sample I took in, but the first coat on the base looks a lot different than the sample.  However it is still a nice colour and it may change as it dries - I've had that happen before.  I do have the tailstock but forgot to put it on for the pics.
Below is a link to the UK Lathe site for the lathe as well as some pic of the progress.
http://www.lathes.co.uk/cromwell/
Thanks,
Michael


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## xalky (Dec 12, 2013)

That's a really nice lathe. It looks to be lightly used and in real good shape. Thanks for the pics. I'm looking forward to your progress.


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## valleyboy101 (Dec 13, 2013)

Today I got the second coat of paint on the base.  Not really happy with the paint - it doesn't level out like it should.  Today I sanded out all the brush marks from the first coat - only to redo them on the second coat.  I'm using top quality brushes and paint.  Maybe I should thin it? Shouldn't really be necessary, but maybe.  I can live with it in the base if I have to, but not on the lathe itself.  I'll have to experiment tomorrow - any ideas.  I have an air brush and touch up gun but don't really want to spray in the house in the winter.  Thinning may be the only answer.
Tomorrow the lathe goes on the cabinet so at least I wont be crawling around and around the base like a rat, only I have sandpaper or a paint brush in hand.
More pics Sat.
Michael


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## valleyboy101 (Dec 14, 2013)

Hi All,
Today I got the lathe back on its base and mostly stripped down, getting ready for cleaning, sanding, and paint.  The gear box is slow to reveal some of its secrets of disassembly to me - that is why it is still in place.  I could paint without removing it, but would really like to take it apart and give it a good cleaning.  Things are actually going good, in that so far I haven't found anything that gives me a sick feeling and sends a cold shiver down my spine. There is some swarf in the carriage and the usual bits of dirt here and there - looks like it has cut a lot of brass.  See for yourself, I have attached some pictures below.  Any advise from Cromwell gear box diassembly experts, or even other amateurs would be appreciated.
Michael







.


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## valleyboy101 (Dec 16, 2013)

I would have posted more photos and some questions but my iphone has quit uploading photos.  Lots of hours cleaning parts and almost as many trying to get my photostream back in business.  I have a question about the oilers on the lathe - they are a little bit like a zerk fitting but don't lock on.  Several of them are even located on the bottom of the part that needs to be oiled ie. the oil has to be pumped upwards.  Hopefully I'll have some pictures Tues. to show it better than 1000 words.
Michael


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## valleyboy101 (Dec 18, 2013)

Monday I was removing parts from the lathe for cleaning and came across this little jewel - actually the F-N-R tumbler gear set.  I was surprised that it is its own gear box and not open mounted as I have seen in the past.  I attached 3 pics, 2 before and one after cleaning.  In the last picture the steel gear is pushed forward due to the way I set it down.
Michael
The pictures don't seem to be showing up, you can click on the links to see them.  Sorry - I'll do better in the future.


View attachment 66234
View attachment 66235
View attachment 66236


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## valleyboy101 (Dec 20, 2013)

Sorry about the previous post.  The phone and computer are communicating again.  Where we be without contrary electronics to help us reach levels of frustration and patience that previously couldn't be imagined?
Below are the 3 pics that should have showed up last time.
Michael


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## f350ca (Dec 23, 2013)

Coming along nicely. Its amazing where brass cuttings can lodge themselves. 
Missed your posts on this till now, On the paint, I've used automotive enamel hardener in regular enamel paint with great results, it sets way quicker and gives a better sheen. But does give off its own vapours, they don't last long but might be a problem in the house.

Keep up the posts

Greg


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## valleyboy101 (Dec 23, 2013)

Hi Greg,

I changed brands of paint from Ben Moore to Beauitone and it is really a lot better at leveling out. I started putting the lathe back together today. The reason I finished the bed was to earn spousal credits.  Once I finished the bed I was given the rest of the month off, for play.  I should have more pictures tomorrow, but I also have some prep work to do for the family Christmas dinner.  My greatest Christmas wish is for Santa to help me figure out the electricals.
Michael


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## valleyboy101 (Dec 26, 2013)

The lathe is back on it's base and mostly together.  I still haven't got the correct setup of the thrust bearings at the right end of the lead screw, but I'll get there.  I haven't installed the cross slide and the compound because I discovered they were engine turned (jeweled).  I'm not sure if it is original from the factory or done by an owner (the Canadian Govt. was the original owner and I don't think they would have done it, so maybe it is originnal). It is virtually all worn off, but still bright under a brass protractor plate.  I don't really want to take the time right now but it would sure look sweet. Although I have always wanted to try it I have never done engine turning before so I will practice on a scrap and see how I do.  
Michael


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## mattthemuppet2 (Dec 27, 2013)

damn that is a sweet looking lathe. Really novel arrangement for the carriage feed too. Nice work!


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## valleyboy101 (Dec 27, 2013)

Thanks matthempuppet,
Yeah it will take a bit of  getting used to - not having a half nut engagement, threading dial or a hand wheel on the carriage - but I'm looking forward to it.  Not sure that I'll get much done on Sat. as I've got to cut back some snow/ice banks for friends 
Michael


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## valleyboy101 (Dec 29, 2013)

I decided to do the engine turning (spotting) on the cross slide and compound.  The original used a .4" diameter to do the spotting, so I turned down some hard maple to .4"with a half inch shank.  I only had 2 grades of valve lapping compound 400 and 180 grit so I went with the 180.  Tried a few spots an a piece of  scrap and it seemed to look OK, so I went on to the side of the compound - it took about half an hour.   It is a bit blingy, but it would sure catch my in a showroom. So tomorrow it's on to the rest of the parts.  There is a picture below.
Michael


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## valleyboy101 (Dec 30, 2013)

I did the rest of the spotting on the cross slide and compound today.  A fairly laborious process I figure that there are well onto 2,000 spots.  It didn't use all that much abrasive and didn't wear the dowel down very much.  Not that much of a fan of automation in the home shop - but today I did a bit of dreaming in that direction.  Hope you like it, it's my first attempt but looks good to my eye.
Michael


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## f350ca (Dec 31, 2013)

That is impressive Michael. 

Greg


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## JoeSixPack74 (Dec 31, 2013)

Beautiful work.


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## valleyboy101 (Dec 31, 2013)

Thanks Greg and Joesixpack74,
My travel plans were cancelled by lake effect snow, so it's just me and my machines home tonight.  Happy New Year!  
The original wipers on the carriage were neoprene and appear to be original as they are molded to fit.  My concern is that there are no oil holes in the top of the carriage and if tight fitting neoprene wipers wipe it all off - what's left for lubrication?  I have some 1/4" felt that I bought before our local felt mill closed, so I'm seriously considering using it for wipers.  The carriage also has wipers between the front and rear ways - they wipe where the tailstock slides.  There was only one of two installed when I got the machine and it was a skinny little piece of too thin felt, so I've already replaced them with felt.
Any ideas re felt vs neoprene for the remaining 4 wipers?
Michael


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## f350ca (Dec 31, 2013)

Im partial to neoprene wipers, they wipe the way and push chips and dirt ahead of them keeping abrasives out of the mating surfaces. The felt wipers seam to hold chips and drag them back and forth under the felt, there may not be enough pressure to do any real damage though. If the originals were neoprene I'd be inclined to stick with them, manufactures like Cromwell and Hardinge tend to know what they're doing.

Greg


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## valleyboy101 (Dec 31, 2013)

Hi Greg,
I guess that you're right.  The designers know more than I can ever hope to.  I'll go with the original neoprene and maybe add a couple of oil holes for peace of mind.  Happy New Year.
Michael
ps I would have posted pictures of the complete cross slide and compound but the transfer from my phone is screwed up again.


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## f350ca (Jan 1, 2014)

And a Happy New Year to you to Michael. Get that transfer working, we need pictures.
Greg


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## mattthemuppet2 (Jan 1, 2014)

I really don't know what that pointing is for but it sure looks pretty!


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## valleyboy101 (Jan 1, 2014)

Hi Matthemuppet,
It is variously called (and can be googled) as engine turning, spotting, and jeweling.  It is done by applying abrasive to the part to be decorated and then in my case using milling machine to press a spinning dowel against the work for a few seconds - leaving a circular spot.  Then move it table 1/2 the diameter of the dowel and press down again.  Keep on going many times and you have a pattern. 
Glad you like it,  I got the manual this week and the it was a feature of the lathe as it came from the factory.
Michael


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## valleyboy101 (Jan 1, 2014)

Hi Matthemuppet,
It is variously called (and can be googled) as engine turning, spotting, and jeweling.  It is done by applying abrasive to the part to be decorated and then in my case using milling machine to press a spinning dowel against the work for a few seconds - leaving a circular spot.  Then move it table 1/2 the diameter of the dowel and press down again.  Keep on going many times and you have a pattern. 
Glad you like it,  I got the manual this week and the it was a feature of the lathe as it came from the factory.
Michael


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## mattthemuppet2 (Jan 2, 2014)

valleyboy101 said:


> Hi Matthemuppet,
> It is variously called (and can be googled) as engine turning, spotting, and jeweling.  It is done by applying abrasive to the part to be decorated and then in my case using milling machine to press a spinning dowel against the work for a few seconds - leaving a circular spot.  Then move it table 1/2 the diameter of the dowel and press down again.  Keep on going many times and you have a pattern.
> Glad you like it,  I got the manual this week and the it was a feature of the lathe as it came from the factory.
> Michael



so is spotting for aesthetics only or is it similar to flaking surfaces to retain oil? Not that it can't be both of course.


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## valleyboy101 (Jan 2, 2014)

Yes as for as I know it is just eye candy, and although it does trap a certain amount of oil I've never heard of it being used for that purpose, on sliding surfaces etc.
Michael


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## mattthemuppet2 (Jan 2, 2014)

well it certainly succeeds at being eye candy, it looks beautiful


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## valleyboy101 (Jan 2, 2014)

I've made some decent progress over the last couple of days - with the wind chill in the -30's it is a pleasure to work inside. 
The cross slide and compound are both back together, the motor has its shaft turned down from 1" to the required 3/4", and the motor booster is ready to bolt in.  Motor booster may not be a common term but  the shaft of the drive motor is exactly 1" lower than the generator shaft which it couples to.  So the motor needs a boost.  I had some 1 x 4" inch steel that just had to be cut to length.  Now it is drilled and countersunk for the bolts which will hold it to the base of the lathe and drilled and tapped for the motor hold down bolts.

The motor is originally from a table saw, and I think it is a 2 phase although I'm not sure that is the correct term.  It doesn't have a speed switch but does have a large, remote mount capacitor.  My thought is that it uses the phase shift from the capacitor to provide torque for starting and running.

I received the manual from Tony Griffith's site (10 days after order) and the electrical diagram is a great help.  It gives instructions for switching it from 550 V 3 ph, to 230 V 1 ph, and then to 230 V 1 ph.  I am going to put my faith in them - at least til they are proven wrong. Looks promising as when you change from 550 V to 230 V all that you do is bypass the transformer. ie the rectifier is 230 V single phase rather than 550 V
With a little luck it could be "power up Friday"
I have attached some pics below.
Thanks for your comments,
Michael


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## ARM (Jan 3, 2014)

Hello  Michael
Compliments  of  the  Season  and  thanks  for  posting  Your  progress  with  Your  beloved  Cromwell.
Your  work  is  coming  out  nice,  especially  the  Jewelling.  We  use  quite  a  bit  of  this  on  our  knives  with  CRATEX  STICKS  only  on  a  Drill Press.  However,  Your  method  of  utilising  graded  lapping  compound  with a  wooden  dowel  on  a  milling  machine  is  quite  a  novel  approach  to  a  similar  task,  which  we  would  also  like  to  experiment  with.
Regrettably  I picked  Your  progress  a  bit  late,  but  then  it's  never  too  late,  'cos  we  have  a  myriad  of  questions  U  might  be  able  to  assist  us  with  on whether  we  can  or  should  attempt  to  tackle  a  similar  project.    
U  see  we  had  recently  acquired  a  COLCHESTER  CHIPMASTER  which is  in a  pathetically  butchered  condition  and  we  can't  decide  whether  we  should  sell  it  or  keep  the  machine  and  tackle  a  complete  overhaul,  like  U  and  most  of  the  knowledgeable,  experienced  Guys do  here.  Pics  etc.,  are  in  that  section  of  the  Forum  here.
At  the  outset,  allow  me  to  be  candid  and  say  that  we  have  zero  knowledge  when  it  comes  to  the  innards  of  these  Lathes.  
If we  open  say  the  Apron/Saddle,  heaven  help  us  if we  will  be  able  to  put  back  all  the  Gears  etc. !!!
This  machine,  being  rather  noisy,  may  have  VARIATOR  issues,  a  scrape  on  the  BED  requires  removal,  the  MATRIX  CLUTCH  requires  adjustment,  excessive  Back  play on  the  Handwheels  needs  correction  etc.,   etc.   Being  some  33  years  old  it  would  obviously  need  serious  attention.
To  begin  with,  without  sounding  impetuous  or  impertinent,  what  is  Your  level  of  expertise  with  these  machines  ???  Remember,  unlike  U,  we  are  rookies  at  most.
Is  this  Your  first  re-furbishing  attempt  ???
If  U  were  to  advise  one  to  tackle  a  similar  project,  where  would  U  recommend  they  start  ???
We  understand  taking  pics  and  numbering  will  greatly  assist  in  maintaining  a  proper  sequence  of  technical  part  configuration.     
However,  how  would  one  cope  should  one  get  totally  stuck  with  putting  parts  back  in  the  right  order  and  sequence  ???  
Will  the  machine  Manual  adequately  suffice  for  this  ???
Surprisingly we  note  that  U  did  use  a  paint  brush  for  most  of  the  painting,  except  for  what  we  can  see,  the  Motor  ???  
As  moving  our  heavy  ( +500 lbs )  Lathe  would  be  a  serious  challenge,  Your  method  of  using  a  Brush  would  circumvent  that  impasse.  
And  your  work  is  beautiful,  to  say  the  least !!!
We have  had  other  well-intentioned  well  wishers  with  an  exactly  similar  Make  and  Model   on  the  Forum  here  highly  recommend  we  keep  the  machine  and  sort  the  few  problematic  issues.
Regrettably,  we  could  not  make  up  our  minds.
As  an  impartial  observer,  we  would  like  to  pose  the  same  question  to  U.
Should  we  or  should'nt  we  commence  serious  re-furbishing,  knowing  our  level  of  total  technical  ignorance  ???   
Your  esteemed  advices  would  be  immensely  appreciated.
Thanks  in  advance  
Regards
aRM


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## valleyboy101 (Jan 3, 2014)

Hi aRM,
Thanks for the compliments on my Cromwell, but I'm not sure that my opinions are worth esteeming, 
Re the jewelling I used a wood dowel and lapping compound because it was all I had.  Craftex sticks aren't and item I can go to town and buy, and besides it was New Years day and everything was closed.  I read up on it on some excellent sites (saw some stunning work) and determined that you can spin almost any round material that can bring abrasive against the work, in order to make a pattern.
Yes, I have restored other machines, but calling it restoration is a bit of a leap.  Essentially the machines that I have "restored" were all basically sound machines with little wear but looked a little or a lot rough and needed paint and polish - maybe bearings or a part or two here and there.  Sometimes more than 1 or 2 as my Cromwell needs several change gears, an indexing plate and an approx. 4" dial with 250 graduations on it.  
As far as a complete lathe rebuild with grinding and scraping  the ways and everything that goes with that. I have never done it - but I admire those skilled craftsmen and learners that have, and enjoy following their progress.
As far as your Chipmaster goes I remember your posts but can't recall a picture of it.  As for as restoring it goes paint obviously doesn't make it work any better - but it sure looks nice.  There are lots of people doing accurate work on machines with not much paint remaining.  The reason I used a brush was that I wanted a specific colour +-, don't have a spray booth and it is way too cold outside.  Otherwise I might have been able to match it up with automotive spray cans.

It depends what you want your Chipmaster to do for you.  It is not unusual to bring home a new and unfamiliar machine and be a little or a lot overwhelmed - what have I gotten myself into?  As a smart manager once taught me don't look at the whole problem - break it down into sections.  I first used that thinking to do a wood carving project that I never thought that I could do. I thought to myself that I can do that area, and after that I think that I can learn to do the next area and so on - until the project was done.
Any big job is just a series of interconnecting smaller jobs.  To clean it up and get it running you probably don't really have to Know all that much, but you have to be able to learn as you go.  Digital cameras a a big help in record keeping.  Don't take the whole machine apart and end up with a pile of whachyumacallits.  Start with the tailstock, take it apart, clean it, and while it is apart you might as well paint it.  Then do the compound rest - it has only a few parts so shouldn't be too difficult.  
After that I would probably change the lube in the headstock and gearbox (lots of advise on this forum re the correct lube), oil every oil hole you can find, ensure that the gear selectors are fully engaged,  make sure that it sounds smooth when you give it a spin using the belt and power it up a low speed.
Hope this helps,
Michael


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## valleyboy101 (Jan 4, 2014)

Today was power up Saturday.  One small problem is that the contactor coil is 600 V and only hums fainltly at 220 V.  No big surprise, I was trying to be optimistic as last summer when I rebuilt my Startrite bandsaw it was originally a 550 V machine but had a 110 V coil in the contactor.  I'll look around tomorrow and see if I have a suitable coil, if not I'll replace the whole contactor with one I have left from an air compressor.
Hope for the best tomorrow.
Michael


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## ARM (Jan 5, 2014)

> valleyboy101 said:
> 
> 
> > Hi aRM,
> ...


Hello  MICHAEL
Much  appreciate the time U took and spent to respond.
Necessity  is  indeed the  mother of invention  -  and Your lovely JEWELLING just goes to prove that !!
U have also given us stacks to think over with some ingenious and practical methods to go about resolving our quandary.  
Guess we have to now seriously decide what we really want to do, make up our minds for certain and then be determined come hell or high water, that we will want to get this machine right and in perfect working condition.  
Once again a gracious THANK YOU and 
LORD BLESS
aRM


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## valleyboy101 (Jan 9, 2014)

I've been spending alot of time this week - on my knees - thank God they're still good.  I've been figuring out the wiring, lots of problems it appears that the armateur resistance isn't being switched in to the circuit.  Things like that that plus the wiring diagram shows a 3 pole forward reversing switch and mine is a 4 pole and wired up to all 4.  The main and only problem is that the DC drive motor lacks torque.  I beliieve that it is because the armature voltage varies with speed selection and it really should be the field which varies with speed selection - I wish I was as smart as I thought I was 40 years ago!
Michael


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## John Hasler (Jan 9, 2014)

valleyboy101 said:


> I've been spending alot of time this week - on my knees - thank God they're still good.  I've been figuring out the wiring, lots of problems it appears that the armateur resistance isn't being switched in to the circuit.  Things like that that plus the wiring diagram shows a 3 pole forward reversing switch and mine is a 4 pole and wired up to all 4.  The main and only problem is that the DC drive motor lacks torque.  I beliieve that it is because the armature voltage varies with speed selection and it really should be the field which varies with speed selection - I wish I was as smart as I thought I was 40 years ago!
> Michael



You vary armature voltage to control the speed of a shunt-wound DC motor.


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## f350ca (Jan 15, 2014)

Michael, any progress on the wiring?

Greg


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## valleyboy101 (Jan 15, 2014)

Hi All,
The lathe is all back together and runs nice and smooth and should be even better once it is on a solid floor rather than 2x6's and pipe rollers.  There is only one problem - the drive motor has very little torque at low speeds.  I have checked the electrical wire by wire and corrected a couple of problems.  However as it stands now the generator is delivering correct 170 V DC to the motor field and the motor armature voltage varies by speed as it should.  So I guess the only solution is to take the motor out and have it checked out by a motor shop.  Not really looking forward to removing the heavy under mounted motor and even less so re installing it.  Anyway off to the shop ASAP.  I attached some picture of the lathe below, just a couple of paint touch ups to do.
Michael


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## f350ca (Jan 16, 2014)

WOW it turned out great, you must be proud. Looks to good to get dirty.
Greg


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## samthedog (Jan 16, 2014)

Lovely work mate. Please send Tony some pistures so he can immortalize your lathe on his site )

when you say the machine lacks torque in the low speeds, are you saying you can stop it turning by hand? How are you measuring the torque?

Paul.


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## genec (Jan 16, 2014)

that is one fine looking machine. 
:man:


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## valleyboy101 (Jan 16, 2014)

Hi samthedog,
I'm measuring torque by hand ie. using a paper towel to grab the spindle or the motor pulley and try to stop it.  At 400 rpm I con stop it with no problem.  The motor brushes and comutator look to be in excellent condition.  I have trouble believing that it the motor, but have nothing else left to check.
Michael


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## core-oil (Jan 16, 2014)

Michael,

 you mention lack of toque on your motor at low speeds, Is your lathe fitted with back gear? If so that means by using the back gear you can use the drive motor a little faster & increase torque generally , The big old lathes where I once worked had to work in this manner to avoid frying the old D.C. motors 
  good luck with a really lovely & versatile machine.


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## valleyboy101 (Jan 16, 2014)

The lathe is suppose to be capable of 200 - 2000 in direct drive and 30 - 200 rpm in back gear.  If there were other users around I could ask them, but it's a fairly rare lathe so I haven't heard from any other users.  It does seem like a bit of a stretch for it to run at 170 V field and only 40 V armature voltage and still develop good torque at 200 rpm.
Michael


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## John Hasler (Jan 16, 2014)

valleyboy101 said:


> Hi All,
> The lathe is all back together and runs nice and smooth and should be even better once it is on a solid floor rather than 2x6's and pipe rollers.  There is only one problem - the drive motor has very little torque at low speeds.  I have checked the electrical wire by wire and corrected a couple of problems.  However as it stands now the generator is delivering correct 170 V DC to the motor field and the motor armature voltage varies by speed as it should.  So I guess the only solution is to take the motor out and have it checked out by a motor shop.  Not really looking forward to removing the heavy under mounted motor and even less so re installing it.  Anyway off to the shop ASAP.  I attached some picture of the lathe below, just a couple of paint touch ups to do.
> Michael



How are you varying the armature voltage?  DC motor torque is proportional to armature current.  If you are using a rheostat to vary armature voltage you can't expect much low-speed torque.


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## valleyboy101 (Jan 16, 2014)

Thanks John,
The field runs at 170 V DC and the armature varies from 40 to 220 V DC depending on where the potentiometer is set to vary the speed.  At 200 rpm the armature voltage is about 40 V DC.  It is a Ward Leonard design drive system.  I agree that I shouldn't expect much torque from such a low armature voltage.  However the system is wired as per the wiring diagram and I can't believe that it was originally such a torquelss wonder.  The manual brags in a restrained British manner about its torque at all speeds.
As I said previously I honestly don't believe that there is a thing wrong with the motor.  It is a shunt wound motor.
Any suggestions?
Michael


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## John Hasler (Jan 16, 2014)

valleyboy101 said:


> Thanks John,
> The field runs at 170 V DC and the armature varies from 40 to 220 V DC depending on where the potentiometer is set to vary the speed.  At 200 rpm the armature voltage is about 40 V DC.  It is a Ward Leonard design drive system.  I agree that I shouldn't expect much torque from such a low armature voltage.  However the system is wired as per the wiring diagram and I can't believe that it was originally such a torquelss wonder.  The manual brags in a restrained British manner about its torque at all speeds.
> As I said previously I honestly don't believe that there is a thing wrong with the motor.  It is a shunt wound motor.
> Any suggestions?
> Michael



That's really interesting.  I've read about Ward Leonard systems but I've never actually seen one (I'd love to have a chance to play with one).  It should give you full torque down to quite low speeds.  Something is wrong.   Can you post the wiring diagram?  Here is a link to the Wikipedia article that explains how it works http://en.wikipedia.org/wiki/Ward_Leonard_control

BTW weakening the field of a large DC motor will speed it up, not slow it down.  If you interrupt the field while the motor is running it can speed up so much it explodes.


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## valleyboy101 (Jan 16, 2014)

Wisconsin isn't that far away.  Seriously, I just tried to scan the electrical diagram but my computer has lost its driver for the scanner so i'm in the process of reinstalling it.  I'll post it as soon as I can.
Michael


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## valleyboy101 (Jan 17, 2014)

Sorry, but I'm having absolutely no success inserting a wiring diagram.  I can upload it, but no way will the scan (or any of my previous pictures) insert the into the post.
I'll keep trying.
Michael


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## John Hasler (Jan 17, 2014)

valleyboy101 said:


> Sorry, but I'm having absolutely no success inserting a wiring diagram.  I can upload it, but no way will the scan (or any of my previous pictures) insert the into the post.
> I'll keep trying.
> Michael



Seems to have worked this time: I see a diagram.  Is that exactly how the machine is wired?   In any case, assuming correct wiring my suspicions fall on the rectifier.  What does the DC motor armature voltage do when you stall the spindle?  What does the AC motor do?  Does it slow down?


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## valleyboy101 (Jan 17, 2014)

No the AC motor never slows down.  Tomorrow I'll check the rectifier voltage under stall conditions.  The lathe is wired the same as the diagram, with the exception of cutting out the 3 phase.  The rectifier seems to put out its rated voltage.  I tried over 10 times to post the wiring diagram, but after I wrote my apology for not being able to  -  well there it was.  I guess it is the mystery of the internet.
Michael


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## John Hasler (Jan 18, 2014)

valleyboy101 said:


> No the AC motor never slows down.  Tomorrow I'll check the rectifier voltage under stall conditions.



Please also check the DC motor armature voltage and the DC generator voltage under both stall and no-load.



> The lathe is wired the same as the diagram, with the exception of cutting out the 3 phase.
> Michael



Exactly how did you do that?


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## valleyboy101 (Jan 18, 2014)

OK here are some readings taken at 240 rpm under no load and stall conditions, all in V DC.

                   No Load         Stall
Gen.  Field        12.6           1 2.6
        Arm.        33.8            30

Motor Field       189             189
        Arm         26.7            26.7

Hope they shed more light for you than they do for me.  Now I'll go study the wiring diagram some more.
Michael


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## John Hasler (Jan 18, 2014)

valleyboy101 said:


> OK here are some readings taken at 240 rpm under no load and stall conditions, all in V DC.
> 
> No Load         Stall
> Gen.  Field        12.6           1 2.6
> ...



The generator voltages are about as I expected: the load drops the output a bit.  The motor armature voltages don't make sense.  The notation in the drawing is peculiar but, knowing how a Ward Leonard works, I think I can follow it.  In this mode the motor armature should be connected directly to the generator armature.  You might see a few volts of drop due to dirty switch contacts and/or bad connections but the change from no-load to stall at the motor should be as large as or larger than that at the generator.


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## valleyboy101 (Jan 18, 2014)

Hi John,
I did clean the contacts on the drum switch as they were quite stiff and dirty.  All other contacts have been checked and are tight.  I'll try reversing the motor and see if the other contacts on the drum switch make a difference.
Michael


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## John Hasler (Jan 18, 2014)

valleyboy101 said:


> Hi John,
> I did clean the contacts on the drum switch as they were quite stiff and dirty.  All other contacts have been checked and are tight.  I'll try reversing the motor and see if the other contacts on the drum switch make a difference.
> Michael



Did you measure those motor armature voltages right at the motor right across the armature?


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## valleyboy101 (Jan 18, 2014)

I measure the voltage at the brass terminal blocks on the motor and gen., where the wires exit to the internals of the motor/gen.
I checked the voltage drops between gen. and motor armatures and it is 6 V DC in both forward and reverse - with no load.  6 V is an awful lot, like +- 25%.  I don't know if it enough to cause all of my problem, but it certainly contributes to it.
I think i'll re read the Ward Leonard descriptions on the internet.
Michael


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## John Hasler (Jan 18, 2014)

valleyboy101 said:


> I measure the voltage at the brass terminal blocks on the motor and gen., where the wires exit to the internals of the motor/gen.
> I checked the voltage drops between gen. and motor armatures and it is 6 V DC in both forward and reverse - with no load.  6 V is an awful lot, like +- 25%.  I don't know if it enough to cause all of my problem, but it certainly contributes to it.
> I think i'll re read the Ward Leonard descriptions on the internet.
> Michael



I was thinking that maybe the braking resistor was not being switched out when the motor was running: that would account for poor torque.  However, it also would result in a large drop in motor armature voltage when stalled.  The fact that the motor armature voltage does not change when you stall the motor is odd.  What is the condition of the brushes? (I'm grasping at straws.  I wish I could get at the thing in person.)

Could you measure the voltage across the resistor?  Should always be zero except when braking.

Does the drum switch have a wiring diagram on it?  Perhaps that could be used to resolve the ambiguities in that very nonstandard diagram.


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## valleyboy101 (Jan 18, 2014)

Hi John,
I think the braking resistors stay connected all the time.  Maybe I'll try just disconnecting them and see what happens.  No the drum switch does not have a wiring diagram, but I have figured out all its connections.  The switch is a 4 pole - the first I've ever seen, nice touch to show a 3 pole in the diagram.  As you say the wiring diagram does leave something to be desired, but for the cost of the manual it was the only really useful piece of information that I got. ( apart from the weight of the machine)
The commutators both look excellent.  Good pressure on the brushes, no arcing, good undercutting, nice and smooth - almost like new.
After dinner I'll see what I can come up with re the braking resistors.
Michael


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## John Hasler (Jan 18, 2014)

valleyboy101 said:


> Hi John,
> I think the braking resistors stay connected all the time.  Maybe I'll try just disconnecting them and see what happens.  No the drum switch does not have a wiring diagram, but I have figured out all its connections.  The switch is a 4 pole - the first I've ever seen, nice touch to show a 3 pole in the diagram.  As you say the wiring diagram does leave something to be desired, but for the cost of the manual it was the only really useful piece of information that I got. ( apart from the weight of the machine)
> The commutators both look excellent.  Good pressure on the brushes, no arcing, good undercutting, nice and smooth - almost like new.
> After dinner I'll see what I can come up with re the braking resistors.
> Michael



The motor field discharge resistor should be hardwired and should not be disconnected.  The motor armature resistance, if I read the diagram correctly, is shorted out by the switch in run mode.  If that resistor is always in series with the motor and generator you won't get much torque.  However, I'm still baffled by your motor armature voltage readings.  Before you try disconnecting the armature resistance check the voltage across it, both no-load and stalled.

That machine ought to work well and give you good speed control with full torque.


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## valleyboy101 (Jan 18, 2014)

Will do.
Michael


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## valleyboy101 (Jan 18, 2014)

I found my missing 6 V - the braking resistors have it between them.
Then I disconnected them and nothing, no life in the motor.
That and the missing 6 V lead me to believe that the resistors are wired in series rather than parallel.
However I don't really understand how that can be because, as per the wiring diagram contact A1 has one wire to the fuse and one to the resistor, AA2 has one wire to the motor armature and one to the other side of the resistor.
Back at it tomorrow,
Michael


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## valleyboy101 (Jan 20, 2014)

Major Victory!!
I found the source of my lack of drive power.  After a lot more ringing out of circuit and testing of resistances I found the culprit - a burnt contact on the reversing switch.  It was on the pole that switches the armature and one side was still making contact, so when it was switched on it didn't connect across the switch as intended but through the resistors, giving the 6 V drop from gen. to motor.  The motor now runs with lots of torque.  I am embarrassed that it took so long to find the problem but at least it is found.  Thanks for your help John and others.
Michael


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## John Hasler (Jan 20, 2014)

valleyboy101 said:


> Major Victory!!
> I found the source of my lack of drive power.  After a lot more ringing out of circuit and testing of resistances I found the culprit - a burnt contact on the reversing switch.  It was on the pole that switches the armature and one side was still making contact, so when it was switched on it didn't connect across the switch as intended but through the resistors, giving the 6 V drop from gen. to motor.  The motor now runs with lots of torque.  I am embarrassed that it took so long to find the problem but at least it is found.  Thanks for your help John and others.
> Michael



Excellent.


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## valleyboy101 (Jan 20, 2014)

Thanks John.  Your troubleshooting advise was a big help.  The contact was burnt off in such a way that the damage wasn't visible, but it couldn't hide from a VOM.
Now it is just a matter of putting a 220 V contactor on it, moving it into position and leveling it up.  The only big problem is figuring out how to use it without getting it dirty!
Michael


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## f350ca (Jan 21, 2014)

Great to hear you got things sorted out.
I'm currently making some small parts for a CNC plasma table and fighting my worn out Colchester if you need projects, LOL

Greg


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## vettebob (Jan 21, 2014)

Glad You got it running right. Now it's time to get it dirty.:thumbsup:   Bob


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## mattthemuppet2 (Jan 21, 2014)

great job! Electrical gremlin are a pain to deal with, I'd much rather have mechanical problems any day.


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## John Hasler (Jan 21, 2014)

mattthemuppet said:


> great job! Electrical gremlin are a pain to deal with, I'd much rather have mechanical problems any day.



I much prefer electrical problems.  Mechanical ones are expensive.


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## valleyboy101 (Feb 2, 2014)

Last post on this machine - until I start to make additional change gears and a follow rest.

The lathe is moved into its final position, leveled, tailstock lined up with the headstock, and magnetic starter installed.  I connected to micro switch on the back of the bed at the headctock end.  There is an adjustable stop rod on the back of the carriage which opens the micro sw., interrupts the DC motor's armature current - effectively putting the brakes on.  It was intended to keep the carriage and tooling from being run into the headstock.
The wiring kept me on my knees ringing out circuits and comparing them to the wiring diagram for more hours than I care to admit.  Anyway all's well that ends well.

Thank You All for your interest and help, Pics below
Michael


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## mattthemuppet2 (Feb 4, 2014)

wow, that really does look good. Congratulations!


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## Tony Wells (Feb 4, 2014)

That sure is purdy, Michael! I have always like the look of that style casting on a lathe. Just classy. Will be a shame to get it dirty, but it looks easy enough to clean up.

Glad you got the problem sorted.


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## f350ca (Feb 4, 2014)

Sure looks purdy. Going to be a sin to get it dirty.

Greg


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