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arose62
20th January 2005, 10:40 AM
How much effort should be needed to change speeds on a MC1100 lathe?

I know it's going to be easier to change to a slower speed, as you're assisted by the big spring inside the headstock, but should it take a real handle-imprint-in-the-palm-of-your-hand effort over nearly a minute to go from slowest to fastest?

I've got my lathe in pieces to fit a swanky new calibrated label showing the actual positions (replacing the "Slow - Fast" useless label it came with), and thought now's the time to check whether I keep dismantling, or put my name down for the world arm-wrestling championships.

Cheers,
Andrew

PAH1
20th January 2005, 10:47 AM
I have the H&F equivalent of the MC900, I have not had any difficulty in changing the speeds up or down. While not exactly light it requires no more than slight effort to move it from low to high. Have you greased the shafts that the pulleys slide on? I have done on a couple of occasions and that could be a difference. Otherwise you may have a bent shaft on the speed change mechanism itself.

barnsey
20th January 2005, 10:48 AM
Hi Andrew,

I had an MC900 and it never required anything like that kind of effort.

In the owners manual there was a lubrication process to go through, can't remember off hand what it was but it sounds to me like you have a build up of dust/corrosion that is giving you a pai in the a## :rolleyes:

Have you had it since new or acquire it 2nd hand? ;)

Jamie

Termite
20th January 2005, 11:50 AM
Andrew, have a talk to Darryl up the road, he went through this with his and he has a fix for the problem.

DanP
20th January 2005, 12:27 PM
Mine is so tight that it stripped the thread off the rack. Had to dismantle and rotate the rack around to a new spot. Just did it again recently.

Dan.

PAH1
20th January 2005, 12:40 PM
Mine is so tight that it stripped the thread off the rack. Had to dismantle and rotate the rack around to a new spot. Just did it again recently.

Dan.
And I thought I had a bit of a problem with fitting drive belts for a while. Mine sawed three drive belts in very short order, but seems to have settled down now, have not had to replace one for some time.

barnsey
20th January 2005, 12:49 PM
Mine is so tight that it stripped the thread off the rack. Had to dismantle and rotate the rack around to a new spot. Just did it again recently.

Dan.

Geez if I found a rack that was tight and stripped I'd be rotating it regularly :D :D

Seriously though that is a sign of something bent, binding or buggered :eek: Think I'd be hunting down the cause coz if it continues you could be up for serious dollars to fix it or even more for a new lathe :o

smidsy
20th January 2005, 02:16 PM
The speed change should not be that tight.
As part of regular servicing I remove the cover, give that whole area a clean with an air gun and then spray everything except the belt and electrics with a liberal dose of innox.
This seems to work for me.

Cheers
Paul

gatiep
20th January 2005, 04:12 PM
Andrew


First off, this may sound silly to you but in woodturning classes I have heaps of people that try to change the speed without turning the lathe on!

Secondly: Regular blow out, cleaning and lubrication with something like Inox or some Molybdinum dry grease ( in an aerosol ) is necessary. Strip down every couple of months depending on use, clean and lubricate with the grease. Inbetween a spray with Inox at the first sign of getting tight.

Thirdly: Belt damage occurs due to: 1. Trying to change speeds when stationary. 2. Sharp edges on the slots in the pulleys. Bear in mind they are mass produced and for the price they are sold one cannot expect perfect finish by the chinese. Clean up the edges with a bit of wet & dry 3.Some batches had bad belts that didn't last long. Another problem is that the belt is of incorrect length, either a MC900 ( uses a M22 belt) fitted with a MC1100 ( uses a M22 belt ) or on the MC1100 some suppliers have a M23.5 belt on them. In all these cases the belt is too long and at high speed setting the belt starts climbing out of the motor pulley which wears the belt away in no time, and sometimes the belt flies off flies off altogether. Remedy it by fitting the correct belt. There is an adjustment to stop the rack from opening the pulley too much by removing the speed change handle, then the little plate that holds it in place ( 2 screws ), pull out the shaft, turn it a bit and push it into the next slot. Assemble, if you have adjusted the right way it will stop a regular size belt from climbing up on the motor pulley.

Important to remember that just as even the most expensive and prestigious cars require regular servicing, so does your MC900/1100 lathe. It operates in extremely dusty conditions and the dust cakes on the shafts to make it impossible to change speed.

$50.00 from each of you for this lesson on MC maintenance will be gladly accepted! LOL. Enjoy your MC, they do a good job if well maintained.

:)

Ruffy
20th January 2005, 04:12 PM
I had the same problem right from the start with my MC900. :eek: All my weight (not small) was required into changing speeds. Mine also stripped several teeth off the shaft. :(

Spoke to the blokes at Carbatec Canberra the initially replaced the shaft for me with no problems or questions asked. When the same problem kept occuring they replaced the complete headstock again with no problems etc.

The difference is amazing, I can now change speeds up and down easily using one finger only. :D :D :D :D :D

So I highly recommend you take the headstock back to where you pruchased it and get them to replace the whole sheebang. ;)

DarrylF
20th January 2005, 04:38 PM
The problem with the MC900 or 1100 where it becomes difficult to change speeds will eventually lead to it tearing the belt apart - but it's pretty easy to fix.

The shaft at the rear (out of the motor) tends to be a little rough around the keyway etc. The pulleys are alloy and the shaft steel, so the rough edges of the shaft will shave little bits off the pulley as it moves. One half of the pulley moves along the shaft as you change speeds. Eventually it gets all gummed up with a mixture of filings, dust & lubricant and finally stops moving alltogether.

The fix is pretty easy. Remove the cover and the belt. While holding the spring in place on the shaft (I use a clamp), remove the circlip from the end of the shaft (circlip pliers are a good idea), then the washer and spring.

The outer half of the pulley will most likely not want to move easily off the shaft, so you might need the WD40 :) Basically you need to remove it, file down any sharp edges or rough spots on the shaft, clean it all, lubricate and reassemble - being careful not to lubricate the face of the pulleys where the belt runs of course :)

You should also check the pulley at the headstock, clean everything, lubricate where it needs it, and put it back together. Should be running smoothly - run the lathe with the guard off and run the speed up & down slowly and you'll soon see any stiffness etc.

Mulgabill
21st January 2005, 06:17 PM
I had a similar problem with my MC1100 from new and found that one half of the pulley that moves along the shaft as you change speeds was dry and completing lacking any lubrication. A spot of WD40 fixed the problem. On no account force the speed charge.

arose62
21st January 2005, 10:16 PM
Thanks for the various inputs!

My lathe was an ex-demo from H&F, and about $100 less than the usual price, but with full warranty.

The problem was in the main shaft, not the rear (motor) one.

Anyway, after pulling it all apart, taking pictures, some judicious wet-n-dry, running up to SupaCheap for some Inox and threadlock, putting it all back together, noting that the belt was run up too high on the lowest setting, moving one tooth along the rack - it now takes one finger to flick it from lowest to highest speed in a couple of seconds.

Wow! What a difference!!

I smuggled SWMBO's new digital camera into the shed, and took a video of running up and down through the gears, just in case anyone else wants to see how easy it "should" be on a MC1100. It's a 4Mb file, so unless/until I can find how to shrink it, I'll wait for requests to see if there's any interest before I worry about making it available.

Cheers,
Andrew
(who's recalled his entry form for the World Arm-Wrestling Championship)

stingray
27th January 2005, 06:42 PM
For what it's worth. I had the same problem and just renewed the belt ..... 100% improvement.

Rod.

DanP
28th January 2005, 01:10 PM
Bit the bullet and pulled apart my headstock to see what I could see...

It was quite hard to get both the front and rear pulleys off, which it shouldn't be because they should be a sliding fit.

I found that the rear (motor) pulley was full of belt dust. The original belt was rubbish and disintegrated after about a month. Obviously I needed to clean it out better after the belt went kaput. A bit of inox and a tidy up and that one now moves freely on the shaft.

The front pulleys were shocking to get off. Had to 'persuade' them with judicious taps with a soft hammer to work them off the spindle. More belt dust in evidence, but the shaft is poorly machined, with a rough finish. A little light sand should clean that up. The main problem though, is that the key is not in the keyway properly, so it sits up at one end. Also, obviously somone tried to get it to go into the keyway by giving it a light BASHING with a very large sledge hammer :mad: The key is 'bruised' in several places. At least I now know what the issue is. When i can manage to get the key out of the keyway (it's stuck tight) I'll clean it all up and put it back together.

Dan

sailingamerican
28th January 2005, 06:22 PM
Sound like you are having a hard time. Take a fine file or small stone and smooth out the key way. It he key has been hit it might need a slight hit with the file. You need pully pullers to remove most pullies. The cheap ones work well for wood working. Should cost under $10 US I don't know what they are there. More than likely the belt did not last because you need to have the moter runnig when adjusting the variable speed. If you need help drop me an e at [email protected] I was a tool and die maker and have rebuilt many a machine. Hope this helps. Richard

DanP
28th January 2005, 07:21 PM
Richard,

Thanks for the offer of assistance. Not having a hard time, just complaining about the person who put it together. I was a fitter and turner / welder in my past life so I'm no stranger to this kind of stuff, just too lazy to do it when it first became an issue. :rolleyes:

The key was slightly banana shaped, causing it to sit up at one end. Plus there was a bit of smarf in there. I flipped it over and cleaned up the bruises with a file. It was still a bit sticky so I filed the keyways slightly deeper. Polished up the shaft a bit with some emery and voila! Can now move it easily whilst turning the spindle by hand.

I have never moved the speed change without having the lathe running.

Dan

brushy
3rd February 2005, 11:22 PM
On this subject of maintenance on MC900 / 1100 - does anyone have an MC900 manual that I could get copied.

I bought a new MC900 with slightly bent leg and a slightly dickky switch from a Sydney auction house this week. Obviously a manual was in fairyland concepts. Costs etc. will be covered of course.

If anyone else requires an MC900 there is one left at Moorebank Auctions. I paid $220 (incl buyers fee) and bought a drive dog and live centre as they were missing. They had the paper on the lather bed but a bit knocked about on some of the spring loaded handles.

Ennis

smidsy
3rd February 2005, 11:32 PM
Hei Ennis,
If you get no joy by Sunday pm me, I can scan mine and e-mail it you but I can't get near a scanner till Sunday.
Cheers
Paul