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Tiger
11th June 2009, 11:14 AM
Anyone who owns an MC900 type lathe would be well aware of having to clean the spindle connected to the motor as it becomes gunked up with dust etc. I do this by taking the circlip off and then the spring and then the Reeves pulley. That is usually the easy part. The hard part (where 3 hands :C would be handy) is mounting it back on because the spring is highly tensioned and you need a lot of pressure while you hold it there and then put the pulley there and then get the circlip on. Just wondering what other turners do here to hold that spring in place, is there a tool that could be used to help here?

hughie
11th June 2009, 11:44 AM
Never used to take my spring off unless I was forced to. I used to blow the shaft down with air and then hit it with WD40 work it back and forth till it was free. Blow the WD40 off and remove as much as possible. Then appy a dry lube so as not too attrack the dust back again.

Skew ChiDAMN!!
11th June 2009, 03:33 PM
Ya know, I've stripped mine down a couple of times now, but I can't say that I recall anything much about the reassembly?

I'm not sure whether that's 'cos I had no problems or they were painful memories that have been repressed... :rolleyes: Big help I am, eh?

Either way, good luck!

Tiger
11th June 2009, 04:13 PM
I too just apply a bit of WD40 from time to time but everynow and then I take the pulley off because the lubrication failes to have much effect. It's a pain because the circlip holding everything back flies off, the spring which has tons of pressure comes off but after a good clean the lathe speed selector is nice to use. The problem comes when you have to re-install the spring, it's an amusing way to spend an hour or so.

Ozkaban
11th June 2009, 04:26 PM
I'm interested in this - my mc1100 is due for a bit of maintenance, and I've never done it before. The belt is a bit frayed and the it slows down if I put any pressure on the work. Actually, sounds waaya overdue for mainenance!

Cheers,
Dave

arose62
11th June 2009, 04:31 PM
I'm trying to remember how I did mine - I know I looked at the spring, and did a bit of thinking before I tried.....

I *think* I put a clamp on the spring BEFORE I took the circlip off, so it didn't fire the circlip/pulley/whatever across the garage, never to be seen again. The spring stayed compressed, so replacing the bits on the shaft was no drama.

Or did I put a clamp to pull the pulley back against the spring?

Something like that - definitely

1) clamp
2) remove circlip
3) ease off clamp
4) disassemble & clean

Cheers,
Andrew

jefferson
11th June 2009, 04:39 PM
Excuse my ignorance, but what's an MC 900? It sure seems to be a popular lathe.

Jeff

arose62
11th June 2009, 04:40 PM
Getting forgetful - I can remember some of the thinking, but not the actual doing :C

Maybe I tied the spring in the compressed position with some stout wire?

Cheers,
Andrew

Ozkaban
11th June 2009, 04:42 PM
Excuse my ignorance, but what's an MC 900? It sure seems to be a popular lathe.

Jeff

Generic chinese cheapie along with the MC1100. made by about 400 different companies out of 3 factories. :rolleyes:

Cheers,
Dave

bowl-basher
11th June 2009, 05:30 PM
just went down this road myself found that by ass. te motor pully without the belt on it is so much easyer to do as the pully closes just that much more
bowl Basher

Skew ChiDAMN!!
11th June 2009, 06:12 PM
Getting forgetful - I can remember some of the thinking, but not the actual doing :C

Ditto.


Maybe I tied the spring in the compressed position with some stout wire?

Sounds vaguely familiar. :think: I'm pretty sure I didn't use a spring clamp. Or did I? No... I don't think so. The only spring clamp I have is for cylinder heads and wouldn't work on these pulleys.

DJ’s Timber
11th June 2009, 07:23 PM
just went down this road myself found that by ass. te motor pully without the belt on it is so much easyer to do as the pully closes just that much more
bowl Basher

He has it the nail on the head, remove the belt first and the spring is fairly easy to compress.

joe greiner
11th June 2009, 11:07 PM
It seems a lot of the resistance to speed changes comes from the rack driven by the speed handle. The round rack engages a hole in the front of the headstock, which may become lodged with dust. Tape or a closure plate might overcome this. But in the meantime, or even afterwards, spray some lube into the hole. The "hole" is about 1/2" diameter, not the dead centre divot in the end of the rack. DAMHIKT.

Cheers,
Joe

bowl-basher
12th June 2009, 10:47 AM
I also found that 'INOX" spray is the best as it drys and leaves a film of dry teflon lube that the dust dose not stick to. Real good on the ways of the lathe and magic on chucks ( no interest just a happy user) also removed and cleaned the rack and adjusting lever refitted with dry graphite grease
Regrds
Bowl-Basher

Bagmann
12th June 2009, 11:25 AM
I agree with the above, having just done this the belt needs to be removed. But just to ask a question while on the topic of the old MC900, has anyone ever chaged a motor in one?

Cheers

Simon

Tiger
12th June 2009, 12:59 PM
Bagman, I had to change the motor last year, as long as the wires are connected properly, not a big drama.

From memory I did take the belt off but the spring was still difficult to work with.

Arose, I think Carbatec actually suggested that you use a clamp but what sort of clamp would hold the spring down on the pulley?

Bowl-basher, I use INOX too but the spindle will gunk up and require a thourough clean at some stage.

arose62
12th June 2009, 02:21 PM
Well, I have a couple of vice-grips, some Quik-Grips, and a couple of G-clamps - so it would have been one of them :)

Bagmann
12th June 2009, 05:28 PM
Tiger, upon having time to remember what I did, the way around the problem is to:
1) loosen the fixed pulley & slide it along the shaft away from the circlip as far as possible, thereby reducing the amount of compression required.
2) put on sliding pulley, spring assembly & circlip
3) slide fixed pulley back & tighten grubscrew, should be easier to pull it into place & operate the allen key than trying to squash springs etc.

Hope this helps

Simon

joe greiner
12th June 2009, 07:40 PM
I agree with the above, having just done this the belt needs to be removed. But just to ask a question while on the topic of the old MC900, has anyone ever chaged a motor in one?

Cheers

Simon

IIRC, Skew has mentioned re-locating the motor to reduce intrusion in the working space.

Perhaps he can be persuaded to reveal the details, if he can recall them.

Cheers,
Joe

Skew ChiDAMN!!
13th June 2009, 02:50 AM
IIRC, Skew has mentioned re-locating the motor to reduce intrusion in the working space.

Perhaps he can be persuaded to reveal the details, if he can recall them.

The simplest method is to simply by an appropriate motor that spins in the opposite direction. Then a little bit of metal-work to mount it so the reeve pulley sits in the same place, but with the motor on the opposite side.

In my case, a lay shaft was put there instead, with a pulley cluster on the opposite end. The motor was moved to the top of the headstock, so it takes two belts: one from the motor to the lay-shaft & another for the reeves drive to the headstock.

Would've worked better if the maths had been done right in the first place, though. (It ain't a good idea to choose pulley sizes for a 1440RPM motor when you have a 2800... :doh::B)

But as to remembering the helpful little details - like putting that damned pulley back on... :no:

Calm
13th June 2009, 10:01 AM
my Hafco WL18HD which was a "special" they brought out had the motor on the other side (not protruding into workspace). I have since changed it to EVS but the motor is somewhere in the shed along with brackets etc.

When it had the reeves pulleys about every 3 months i would remove the guard, blow it out with air and spray with inox/WD40/CRC whatever was around. I found if you make sure the guard is always on the problem of sticky pulleys is reduced.

Another little trick i did was fit - under the spring - on the motor shaft a collar that stopped the pulley opening up further when on the lowest speed setting. This meant the belts didnt come loose when loaded up. As for removing the circlip, remove the belt and it is quite easy.

Hope that helps

Cheers

joe greiner
13th June 2009, 10:41 PM
Thanks, Skew. I thought it was more complicated than just moving the motor topside, because the shaft length wouldn't change.

And, y'know, your 1440 is 1725 here, because of the frequency difference.:(

Cheers,
Joe

Fireguard
28th July 2009, 01:05 PM
I've just stripped my lathe down, It's quite an old version of the MC900 that I inherited from my Grandfather.

Well looks like the 2 bearings in the headstock have pritty much had it... After a bit of belting I finally managed to get these out, The only one that was the pain though was the bearing thats inside Half of the Top pully, I was trying to knock it out and the casting on the end of the pully where the circlick sits broke off. So I rang Carbatec and order another (can't get one, They come as set :) ). then i noticed that the other pully connected to the motor had a BIG crack down the side.. So I've also ordered the other set of pullys....

Since I have the lathe apart anyway and I'm waiting on parts, is there anything else maintenance wise I should do to the motor or lathe whilst I've got head all apart ???

RETIRED
28th July 2009, 01:36 PM
Put a spare belt in there.

joe greiner
28th July 2009, 10:20 PM
As luck would have it, Tiger's other thread on Access Panel (t=47550) provides pictures of Skew's modification, which I hadn't entered in my index of WWF threads. And now I've saved the pictures, too.

A second copy of my HF34706 (sister to MC900) has been riding around in the back of my truck for about a month, waiting for space in my sliding-block puzzle of a shop.

Thanks, Skew and Tiger.:2tsup:

Cheers,
Joe

Fireguard
3rd August 2009, 08:33 PM
Finally got a chance to change the bearings..... The main shaft is now spinning nice and smooth now...

And as luck 'wood' have it I pulled the speed selector apart and gave it a good cleanout, The bottom guide groove was full of dust etc at each end... after cleaning it out I now have an extra speed slower and an extra one faster :2tsup::2tsup:

I've just got to wait for the pully things to arrive and i can start spinning up some more mess :D:D