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reeves
25th July 2006, 10:51 AM
HI all, its time to do deeper levels on maintainnace on my lathe, change belt and grease gears.

I busted the pully wheel trying to get it off to change the belt, got a new one...ready to go..

?q--> does anyone use a specific method o removal or tool to do so ?

i found it stuck on tight, i had removed circlip and grub screws, turned on and sped up to seperate the wheels...still could not budge it..eventurally hit the edge of the wheel too hard with a rubber mallet...ooch!


Alo is there specific way to grease the gears or do i need ot take off the speed handle mechanism to get in there...

cheeeeeeers
john

hughie
25th July 2006, 01:18 PM
John,

I am gonna assume your MC900 has an identical set to my MC1100.

When you have removed the circlip that retains the pulley against the spring tension. It should in theory slide off, but like mine it was covered in gunk -- dried grease, wood dust etc. So liberally sprayed it with WD40 and worked it in until it slid of the shaft. After this cleaned up the shaft checking for burrs etc. I reassembled with dry lubricant, working it up and down until it moved freely.
If it does not pull off in future then you may have to resort to a wheel puller, two prong or three prong. They readily available at any after market auto spares store...chiwanese :D not so expensive, you don't need a fancy one as its a cast ali pulley and it wont take a lot of strain.....well I guess you have found that out :o

I knocked/chipped a chunk of mine the first time it did it as well :o it still works....well sort of. Later I rebuilt the whole thing with a different set of stepped pulleys and a inverter.

hughie

arose62
25th July 2006, 01:41 PM
I sprayed my MC1100 internals with Inox (on recommendations from this forum).

You didn't mention which pulley(s) you were having problems with: the one on the motor shaft, or on the headstock shaft.

And, I didn't think you'd need to remove a pulley to change a belt (something I haven't had to do yet).

Anyway, once the motor pulley is moving freely, be sure to have something to compress the spring on the shaft before removing the circlip, and something to catch the circlip!! (A pile of sawdust/shavings is NOT a good option for this. DAMHIKT!)

Cheers,
Andrew

TTIT
25th July 2006, 01:49 PM
Geeeeeez:eek: I thought it was just us bushies that were too heavy handed:o.
I cracked a chip off the pulley on mine when I first took it off by conveniently dropping it on the cement floor!:( My mate bought an MC900 that hadn't been used for some time and smashed the pulley while trying to get it off because of the rust, gunk etc that had built up.
Those pulleys are shamefully weak so anyone toying with the idea of removing them should take great care!:).....Hmmmm - my bearings are getting a bit noisy and I'm more worried about getting the pulleys off in one piece than getting the old bearings out;)

reeves
25th July 2006, 01:52 PM
thanks guys for those responses..i

ts the top pully on the spindle, the larger one and the reason i was trying to remove it was the belt wont fit around it, the wheel edge is too close to the casing about 3-4 mm i tried, just would not fit over..

i would love to change it without removing a wheel...

i had removed the lower wheel but then notice i could not fit the belt over the top one so i figured rmeovingt hem would be too mush hassle..
anyways the front top wheel is now removed and am working on the back one...burr on rim near circlip holder main stoppage..now for the rear one..

new wheels and capacitor arrive 2morrow, carbatec were sharp and fast...

cheeeeers
john

Skew ChiDAMN!!
25th July 2006, 05:24 PM
Welcome to reality, John. The MC-900 is a damned good lathe for it's price, but now you're finding out about its' more serious shortfalls...

One of the projects in my 2doQ (to do queue :rolleyes: ) is to cut away the casing around the top pulleys and install an access plate. Haven't got a round tuit yet, solely because the only time I think of it is when I have to change the belt 'cos I'm in the middle of a project and then I don't have the time to play with modifications.

Thank God it's the sorta thing ya only gotta do once every blue moon, eh? :D

Tornatus
26th July 2006, 12:31 AM
I'm a bit surprised that the word has not been passed around previously about changing these belts - you certainly shouldn't have to go through the drama of removing any pulleys from their shafts, BUT (as others have noted) you must give the whole assembly a good clean and lubricate with Inox before fitting the new belt. You'll be amazed how smoothly the variable speed mechanism works after a clean & lube.

After fitting the new belt loosely over the bottom pulley, use a large (engineer's) screwdriver to CAREFULLY wedge open the bottom pulley against its spring - try not to scratch or otherwise damage the pulley's conical faces in the process. This will let the belt pull into the bottom pulley groove far enough to allow sufficient slack on the other end to slip over the top pulley - done!

It's a good idea to smooth & polish the inner pulley faces to minimize wear on the belt and assist in speed changes - this is of course best achieved by disassembling the pulleys, with all the attendant drama, but it's worth it if you feel up to it (a proper circlip tool makes a world of difference). Use grades of wet & dry to remove any machining marks from the pulley faces, and finish by polishing as smooth as possible with a good metal polish like Autosol (just don't get any in the bearings or on the shafts!)

Another good tip is to buy a quality "A Section" belt for your lathe, rather than the el cheapo variety which comes with it - from memory, the appropriate code is A22, but take your old belt along to verify the size.

With regular cleaning and lubrication of the Reeves Pulley mechanism, and remembering to ALWAYS return the lever to the lowest setting before switching off, you should enjoy long intervals between belt changes.

Skew ChiDAMN!!
26th July 2006, 01:11 AM
I'm a bit surprised that the word has not been passed around previously about changing these belts - you certainly shouldn't have to go through the drama of removing any pulleys from their shafts, BUT (as others have noted) you must give the whole assembly a good clean and lubricate with Inox before fitting the new belt. You'll be amazed how smoothly the variable speed mechanism works after a clean & lube.

I'd like to add that in good repair the variable speed lever should be movable with just one finger. If it starts sticking, or becomes harder to shift, it's time for a clean and lube.

However, now I'm wondering if there's a bit more variation to the MC- series than I'd thought. I know for sure that on my "hard-knocks" MC-900 there's only about 5mm clearance between the pulley rim and the casing. No matter how smoothly the mechanism works, there physically isn't any room to "slip over the pulley," short of "ferreting" it through too a small gap. :( Not really good for the belt, or my temper for that matter. :rolleyes:

I'll have to check my "finishing" MC... which is about 15 years more recent. I don't recall changing any belts on it yet, so it may be a problem they've rectified. Find out tomorrow, I guess.

hughie
26th July 2006, 01:44 AM
for sure that on my "hard-knocks" MC-900 there's only about 5mm clearance between the pulley rim and the casing. No matter how smoothly the mechanism works, there physically isn't any room to "slip over the pulley," short of "ferreting" it through too a small gap. :( NotHowever, now I'm wondering if there's a bit more variation to the MC- series than I'd thought. I know really good for the belt, or my temper for that matter. :rolleyes:


Skew,
I cut a fair bit out of my casing, best thing I ever did. :) I found it easier to strip the pulleys down as it gives more room to move.
It cuts real easy either by hacksaw of one of those 1.5mm cutting discs, ran around the edges with a flap disc to clean it up. All in all about 2 hrs work , up and running again
hughie

reeves
27th July 2006, 11:37 AM
ok, now what didnt someone tell me about the circlip 'behind' the inner top wheel, the one u can't see cos of the black cast structure...mmmm

and yes Hughie my problem is the same, u just cant fit the new belt over the upper wheel cos its too close to the casing, grinding the casing away seems a good option.

thanks for the responses guys

regards
john

arose62
27th July 2006, 01:54 PM
Hey Reeves,

you did remove the circlip 'behind' the inner top wheel, the one you can't see because of the black cast structure, didn't you :D :D :D

Cheers,
Andrew

DanP
27th July 2006, 02:15 PM
Once you have the pulleys off, check the keyways. That was where mine was binding. I had to tidy up both the keys and the keyways to make it run as it should. You will be amazed at the diff.

Dan

Skew ChiDAMN!!
27th July 2006, 04:09 PM
I cut a fair bit out of my casing, best thing I ever did. :) I found it easier to strip the pulleys down as it gives more room to move.
It cuts real easy either by hacksaw of one of those 1.5mm cutting discs, ran around the edges with a flap disc to clean it up. All in all about 2 hrs work , up and running again

It's definitely in my 2doQ, just a matter of finding the time and inclination.

Thin cutting disks, you say? One of the reasons I've been putting it off was the thought of toiling away with the ol' hacksaw... didn't even consider the angle-grinder. :o The odds of the mod actually happening here have just been improved considerably. ;)

arose62
27th July 2006, 07:17 PM
I posted this ages ago, but after seeing a few comments on the "one-finger" speed change, I think it's timely to repost.

This video shows how it SHOULD be, after I got tired of wrestling with my MC1100, and got heaps of info from this forum.

"And a video of how smoothly the speed changes after cleaning out inside the lathe head
http://people.aapt.net.au/rosefamily/LatheSpeedChange.MOV

(about 4 Mb, so it'll be painful over dial-up.)"

Cheers,
Andrew

reeves
28th July 2006, 01:11 AM
ok the saga continues, with lend of gear puller fomr Andy Mac, i have managed toremove stubborn old wheel ( eventually using bandsaw to cut aluminum hub from bearing casing). In my enthusiasm to get new wheel on i rubber malleted it over spindle and its a bit tight so stuck on, shaft wont slide.
Now gotta re remove it and hone inside of new wheel....remove mor e burrs

i can see light at the end of this tunnel, just a little more time.....

lathe and i r bonding on new levels....
mmmm

hughie
28th July 2006, 01:43 AM
Thin cutting disks, you say? One of the reasons I've been putting it off was the thought of toiling away with the ol' hacksaw... didn't even consider the angle-grinder. :o The odds of the mod actually happening here have just been improved considerably. ;)
[/QUOTE]

Skew, go for it,I Chucked caution to the wind chopped as much as I wanted too
The flap disc will remove allot as well, so you can trim it up to remove any indiscretions cause by the cutting disc ;)

hughie

reeves
30th July 2006, 10:26 AM
YEEEHAH!!!!!!!!!!!!!!!!

its done, lathe is rebuilt and WORKING fine, what a frigging miracle of endurance. Big thanks to Brett at Crabatec in brisbane for his invaluable advice on the vagaries of low cost chinese production techniques and the Andy mac for the gear puller.

I have new wheels, belt and capacitor, even with the speed control lever in upside down (i kinda like it), it kicks along.

I now know a lot more about my lathe and feel much more confident about working on it, or sending it off to carbatec for servicing at 35 an hour, saving myself pain and frustration..tho i hope i dont need to change the bearings in the future ;-)

Thanks to all for their advice and when i can get my hands on a small grinding wheel i will surely grind a hole in the side of it to enable changing of belts easier.

To the lathe----------->

cheeeeeers
john

cedar n silky
31st July 2006, 11:12 PM
Good to hear your"back in the sadle"Reeves. Nothing worse than the lathe being down!!:eek: Enjoy the turning.:)