New Cromwell S800 MK3 Lathe

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
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
 
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
 
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.
 
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

002.JPG003.JPG

002.JPG 003.JPG 004.JPG
 
WOW it turned out great, you must be proud. Looks to good to get dirty.
Greg
 
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.
 
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
 
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.
 
Back
Top