Clausing/Colchester 11" (Colchester Bantam 2000)

Yes, they're overfilled. You all guilted me into opening up the top and draining out the excess. I usually run them slightly over the mark due to slower reaction times (oh, crap, I guess that's too much) and a general apathy towards gearbox levels. The lower box was overfilled to the top of the window which worked out to 4oz. and the top one was the same level over but the gearbox is larger and that worked out to about 12oz over. I did find that the two main bearings are lubricated by oil being flung off the gears to the top where the oil drips into two holes which weep onto the gears - very precise. One was slightly blocked with swarf so that was good to find and clean out but otherwise the gearbox looked perfect. I could be wrong but I doubt there's too much issue with the gearbox being slightly overfilled. It's not exactly spinning at the speed of a motorcycle transmission and they last for years.

The upside is that I needed to top up the oil on the cold saw and now I have some extra.

Gregor
 
I don't know if this is the right place to say this but I made a travelling steady for my Colchester Bantam (I think it is the same lathe as this one). I got a 1" bit of steel laser cut and then machined it from there. If anybody's interested, I can try to dig out some (not very good) drawings that I did and post them here. I ended up changing some of the dimensions a little bit as I made a few careless mistakes in the machining but the drawings would at least be a starting point; and the mistakes didn't affect the function of the steady. I did all the milling on a Boxford VM30, apart from one bit that I had to do on a friend's Bridgeport. Anybody interested? I'll also try to take a picture of the finished item (although I have painted it poorly).
 
Clem,

I'd love to see them, especially with some pics! I am missing the rest and I think that would be a great project.
 
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The common name for the rest that is attached to and moves with the carriage is Follow Rest or Follower Rest.
 
I have a question regarding my (our) lathe. I'm about to turn the most difficult part I've ever turned - a steering stem for a motorcycle fork conversion. I will have to turn dimensions for a shrink fit, a press fit, a slip fit and then a loose fit plus a pair of metric threads of 30x1mm and 28x1mm so it will certainly test my skill.

My question is about runout. I turned the aluminum stock down to 1.125 to fit in the largest 5C collet and drilled the other end for a live center. I turned the whole thing to a dimension with a .010 finish pass over the length. Over the 11" the dimension is .008" tighter at the head stock. That works out to an error of .00072 an inch.

Obviously the sections that require a very tight tolerance are less than an inch so this shouldn't be an issue and I'm sure more precise parts have been made with worse machines but I'm curious if this is a reasonable error and/or what could be done to improve it or if I should just know and accept it and work around it.

Thanks,

Gregor
 
Gregor,

I would check your tail stock alignment. It is probably adjusted a bit off toward the chip pan. You should be able to adjust it by doing that same cut you are doing or use a test bar between centers.

Colin
 
Here they are. I hope they're of interest. The pictures aren't very good, I'm afraid.photo 1.JPG photo 1.JPG photo 2.JPG photo 5.JPG photo 6.JPG Please let me know if you have any questions.
 

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I have a question regarding my (our) lathe. I'm about to turn the most difficult part I've ever turned - a steering stem for a motorcycle fork conversion. I will have to turn dimensions for a shrink fit, a press fit, a slip fit and then a loose fit plus a pair of metric threads of 30x1mm and 28x1mm so it will certainly test my skill.

My question is about runout. I turned the aluminum stock down to 1.125 to fit in the largest 5C collet and drilled the other end for a live center. I turned the whole thing to a dimension with a .010 finish pass over the length. Over the 11" the dimension is .008" tighter at the head stock. That works out to an error of .00072 an inch.

Obviously the sections that require a very tight tolerance are less than an inch so this shouldn't be an issue and I'm sure more precise parts have been made with worse machines but I'm curious if this is a reasonable error and/or what could be done to improve it or if I should just know and accept it and work around it.

Thanks,

Gregor
Hello Gregor,

I'm no expert but I reckon you can get a better runout than that. I've found that, in this situation, I usually drill the end for the centre after I've put the piece in the 5C collet. I also, quite often, end up adjusting the tailstock a little bit, using a clock, once the piece is in the collet with the centre in the end and the tailstock clamped, to make sure that everything is as well lined up as it can be. It might actually prove easier to turn between centres, if you want good accuracy. It's taken me a while to get used to doing things like this but, now that I've done it a few times, I get on OK with it.

I don't know if this is any help. I'm really a beginner myself.
 
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