Colchester Student Mk1 Won’t Start

[Herman van der MerweParticipant @hermanvandermerwe76509]

Hi Richard,

Phil directed me to your thread from the Colchester lathe group on groups.io where I help out.

I am just starting almost exactly the same restoration work on my Student as you have done so far, so I am reading your posts with interest. Good job so far!

At the moment I am restoring (OK let's rather say installing) the wiring on the lathe. Would it be possible to take some more pictures as to the route the yellow wires follow from the drawer switch back to the wiring panel? My lathe has most of the wires removed, so I have no idea where the run the new wires.

Thanks,

Herman

[Richard Kirkman 1Participant @richardkirkman1]

Hi Herman, Just read through your thread. I'll try to get you as many pictures as I can, maybe a video if you're able to view it like my other videos.

Is it just the wiring of the limit switches that you need?

Nice to be helping someone else out for once…

On another note, it's 3 weeks since the light bulb was posted so I've emailed asking them to send another one out.

Meanwhile, I've been enjoying putting the lathe to use. I'm definitely getting more comfortable using the machine and I'm trying to consider my accuracy.

I had two hammer ends lying around, so I thought I would put them to use and make myself a small mallet from some scrap aluminium I had. I think It turned out quite nicely, even with a wood turned Bubinga handle. Not a typical mallet but interesting for me to try some setups.

 

When I was tidying up the machine after, I decided to stick my hand in one of the holes under the headstock. Turned out it was absolutely full of old swarf and grime. It's made me really want to take the headstock off and clean in there, but it seems a bit excessive. Anyway, it's interesting to see all the old chips, completely steel, no aluminium, and some of the swarf must have been at least 10mm depth of cut on the radius. So more clues that the machine has been used plenty. Surprisingly I didn't find any bolts in the hole, but I did pull out loads of shavings, I can't quite reach the bottom, but the machine is probably 1kg lighter

I'll get those videos this afternoon Herman

With regards to your last post on the Colchester forum, My wires are not free, they go through a pipe that goes all the way through the base of the lathe.

Edited By Richard Kirkman 1 on 08/05/2020 11:58:44

[Richard Kirkman 1Participant @richardkirkman1]

Couldn't really get enough access for a video

My wiring is exactly as Phil directed, so that diagram explains it all

The red blue and yellow come from the contactor and overloads in their specified place, then all 3 wires head out the back and up to where the cover switch is. At this point, the yellow goes into and comes out of the cover safety switch

The yellow then goes out of the switch and down the tube going through the lathe body

Then it heads through into the coolant tank

Orientation might be messed up, but i'm sure you can figure it out

In the coolant tank

Then out into where the drawer is

So the wire coming from the cover switch comes into the key switch, then heads straight back up along the tube, then up and into the limit switch.

I hope that helps a bit, happy to answer any questions or get pictures for anything. Just ask. I'm very interested to see how you will wire yours up.

Also, while i was taking pictures of wiring I did a bit of cleaning, brightened up quite well

[Herman van der MerweParticipant @hermanvandermerwe76509]

Thanks for all the pictures Richards. It really helps a lot. It is interesting that your lathe has a removable plate onto which the key switch is mounted. My lathe does not have this plate and it is simply mounted on the body side.

I love your hammer. You are going to use that a lot when you are doing aluminium and copper work.

The wiring I am still thinking about. I discussed what I should do with two factory electrical engineer mates of mine and they recommend that I wire it up to current standards but keep the old equipment I have in place. This means I will install three contactors (one which was present). The first contactor will be to activated the key switch is turned and will make the electrical panel live. The second contactor will be to activate the motor and the third the fluid circulation pump. Fuses will remain in place but be replaced in function by a three pole circuit breaker. That is as far as I have given it thought.

I am thinking of starting a thread of the rebuild somewhere on a forum so that others can learn as well.

[Richard Kirkman 1Participant @richardkirkman1]

Good Luck Herman, I'm sure Phil will get you sorted if you get stuck.

Looking closely at the pictures of your lathe, it's definitely not identical to mine. The castings on the gearbox look different, letters aren't the same shape, and the two speed levers on the top of the headstock are running on a surface instead of being free like mine. It could be an earlier model, but I'm no expert.

I'm not quite sure why you're doing it with 3 contactors when one seems to work fine like in mine?

Anyway, If you do start a thread, please post a link here so anyone interested can see!

[Herman van der MerweParticipant @hermanvandermerwe76509]

Mine is a 1953 model. If you look at https://colchesterlathe.groups.io/g/main/files/Serial%20numbers you can find your lathe's year of manufacture with the serial number as stamped in the tail end of the bed.

I am still in two minds regarding the wiring, but would like to get to our standards but retaining the original equipment as far as possible.

Yes, I am going the thread route as there could be others wanting to go the same route we did. Will post a link here for sure!

[Herman van der MerweParticipant @hermanvandermerwe76509]

What thickness nitrile rubber did you use for the gaskets?

[Richard Kirkman 1Participant @richardkirkman1]

I used 1mm thick nitrile rubber

It was plenty thick enough

A sheet of 500×500 should be more than enough to replace every gasket in the lathe

[Herman van der MerweParticipant @hermanvandermerwe76509]

As requested Richard here is a linky to my restoration project.

1953 Colchester Student Mk1 6" gap bed – A restoration project

[Richard Kirkman 1Participant @richardkirkman1]

Posted by Herman van der Merwe on 12/05/2020 12:13:51:

As requested Richard here is a linky to my restoration project.

1953 Colchester Student Mk1 6" gap bed – A restoration project

Thank you, I'll be reading along, maybe even see if I can help at some point

In the picture of my limit switch you've posted, my wiring is wrong so if you do get one, don't do it like that. Do it like Phils!

[Herman van der MerweParticipant @hermanvandermerwe76509]

Any idea how to get the spindle's chuck cone loose?

[Richard Kirkman 1Participant @richardkirkman1]

Posted by Herman van der Merwe on 12/05/2020 12:55:55:

Any idea how to get the spindle's chuck cone loose?

If by chuck cone you mean the L0 taper part, that's part of the main spindle, so the whole spindle must be removed which I have covered earlier in this thread. There is also a guide in the manual I sent.

[Herman van der MerweParticipant @hermanvandermerwe76509]

If you look at the attached photo you will see that I cannot fit anything between the nut and the cap screw head. I did read your forum post and the manual's section, but alas my lathe's spindle is different. It looks like the cone part can unscrew.

[Richard Kirkman 1Participant @richardkirkman1]

Okay fair enough.

Having the l0 taper screw on and off defeats the point of the taper though. So I don't think it screws off.

Could you try removing the whole spindle?

[Herman van der MerweParticipant @hermanvandermerwe76509]

Hi Richard, you might have seen on groups.io that I did get the spindle out after a LOT of struggling.

How did you manage to get this gear off the shaft? Mine does not want to move.

[Richard Kirkman 1Participant @richardkirkman1]

Yes I have seen. Very interesting stuff, I wasn't expecting your spindle to be anything like that. Enjoying your thread a lot!

The gear was quite hard to get off. There's a locknut on the end of the shaft which must be removed, then there's a washer then the gear comes off. However, my gear was quite stuck. Eventually, after a lot of pulling and pushing and cutting my knuckles on the gears behind it, I managed to work it off. I didn't take out the other gear shaft, but If you have then it should be much easier access as I struggled and ended up pulling and pushing on the actual handle which risked damaging it. Luckily nothing broke for me, but it's worth mentioning.

Then, if memory serves, there is a leather washer behind the gear which acts as a gasket. My lathe was leaking from that shaft so I made a new leather washer which I made very tight to make sure it didn't leak anymore (1 month later, it's still not leaking) Then just reassemble in the opposite order.

Good luck

I'm not sure that yours will be the same as mine. I'll have a look at the pictures of yours

[Herman van der MerweParticipant @hermanvandermerwe76509]

Thanks for the great feedback. I was worried that I am doing something wrong, but it seems this is one of those new word learning exercises. I was thinking (dangerous) and I will make a small gear puller this morning and see if that will work.

Yes, the shaft of mine leaked grease, so there will be no leather washer and I will need to install something new like you did.

Here is what the gear on my lathe looks like.

[Herman van der MerweParticipant @hermanvandermerwe76509]

Posted by Richard Kirkman 1 on 28/03/2020 16:21:38:

As for the tumbler arm mystery, you tell me if I'm being blind, I can't see a dutch key!

Looks like there's the starts of the threads on one the actual tumbler arm, but the shaft doesn't seem to have anything?

Edited By Richard Kirkman 1 on 28/03/2020 16:28:10

Richard, I figured this one out.

You need to remove the grub screw in the cap. Then screw in one of the longer gearbox cover cap screws and then either use a puller or a slide hammer slide the cap of. It is almost a press fit but does slide out. In my case the entry to the hole was damaged, so I countersunk it a bit and retapped the thread.

Then you remove the two revealed grub screws and the main big mamma of a cap screw in the arm and the arm slides off.

[Phil WhitleyParticipant @philwhitley94135]

A solution!! That explains a lot Richard!!

Phil

[Richard Kirkman 1Participant @richardkirkman1]

Solution played out perfectly, except from the oil that leaked out of the end. It was much easier to dismantle than to reassemble, but still not too difficult. It would have been much easier if I had drained the change gear box first!

Still, thanks a lot Herman, very helpful. The more info that's around, the more that it can help others too.

I took it off, cleaned a little, then put it back together.. I didn't want to lose too much oil. But it did make me want to paint it.

Still no LED bulb, 4 weeks since it was posted. I emailed and they've sent another one out last Monday, but now that's already late too! Looks like i'm going to be waiting a while.

I need to replace the gasket at the back of the lathe where the brake is, since that's getting oil in and becoming ineffective.

I also need to look at the other seals again, since i'm getting a bit of a leak out of the end of the main spindle. When I took this to pieces, it seemed like there were rings for a gasket of some sort and a space in the end cover for one too. Any thoughts on that?

[Richard Kirkman 1Participant @richardkirkman1]

You can just see a drip below the spindle. It's not anything to worry about, I know, but if possible I'd like to sort it. Especially if there is a place for a gasket/seal

Edited By Richard Kirkman 1 on 16/05/2020 15:42:42

[Phil WhitleyParticipant @philwhitley94135]

Richard, does yours have the same type of all metal brake as Hermans does?

Phil.

[Richard Kirkman 1Participant @richardkirkman1]

Phil, it is not the same as Hermans, I have material on mine.

The leak is trickling down the lathe and pooling over time in the tray. You can just see a slight bit in here since I cleaned it the other day.

Leak is definitely coming from the inside of the brake

Covered in oil inside. Doesn't make for an effective brake, and makes my lathe messy!

This is where I get stuck. I need to remove the sprung bit, but I cannot seem to get it off. I tried taking out the bolt, but it doesn't feel quite right. There's a circlip on the shaft below that turns to push the brake out, but I don't see that helping disassembly yet. Any Ideas?

I've been working on making a tailstock die holder the past day or so. I've run out of material so I've ordered some steel from my local steel place. So I have a few days to stop this leaking

I also got myself a knurling tool, which arrived today, I tried it out and I'm very impressed, you get so much more grip on knurled parts. I think I'll have to knurl everything now

[Herman van der MerweParticipant @hermanvandermerwe76509]

I am glad you got the arm loose.

Took me two days to get the speed change gear off the handle selector shaft and then another three hours to fix it up. I ended up making a puller.

The gear was knocked oval, the shaft had hammer dings on it that created edges standing out from the shaft and the Woodruff key was knocked about so badly that it was stuck solid. The key took about an hour to flatten on a diamond plate.

All fixed, sliding and fitting as it should.

[Phil WhitleyParticipant @philwhitley94135]

Richard, you cant do with oil leaking into the brake drum like that, there is a seal in the flanged bearing (which is actually a bush), take of the brake shoes, and remove the allen screw or screws, depending on which it is, seems like on the early, there is one, but three on the later, and the flange should come off. there appears to be a cork gasket behind it.  the circlip only hold the pivoting cam for the brake into the backplate. Have a look on the parts diagrams on the manuals, that makes it easier to see.

Phil

 

Edited By Phil Whitley on 16/05/2020 19:22:55

Edited By Phil Whitley on 16/05/2020 19:24:09

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