Thread: Jammed MC900 Lathe speed adjuster

Fuzzie H&F's sell parts for these just depends on shaft size almost everything else is same being your closest to Brissy they'd be best choice for service. I recall Munruben getting parts for one he has had trouble with a while back.

I thought that the spline/shaft needs to be in rotation to alter the pulley I could be wrong.

I had read that about only changing speed while it is running, but I think that's only to allow the belts to shift up and down as the pulleys expand and contract with the moving free side.

In this part assembled state I think things should be loose and move easily by hand. As far as I can see there is no centrifugal bearings, its all just based on spring pressure.

Originally Posted by Fuzzie

I had read that about only changing speed while it is running, but I think that's only to allow the belts to shift up and down as the pulleys expand and contract with the moving free side.

Yep. That's how I understand it, too.

In this part assembled state I think things should be loose and move easily by hand. As far as I can see there is no centrifugal bearings, its all just based on spring pressure.

Yeah, the parts should move freely. It has been a while since I pulled any of mine to pieces, but I vaguely remember that one half of the pulley is fixed, while the selector moves the other half of the pulley in and out.

However, I thought it was the outside one - the one you've removed - which was fixed. Which'd mean the inside one'd be the one moved by the selector.

I'm probably misremembering though. Wouldn't be the first time, lately.

I have the "same" lathe (Harbor Freight 34706) in a similar state of incomplete repair. Chances are, the square key is frozen to the inboard pulley half. I'm part way through replacing all the pulley flanges and key, as well as the speed handle shaft, which was damaged by stupidly forcing a speed change with the pulley and key practically welded together.

On the motor, the outboard flange floats in repsonse to speed change, which is accomplished by moving the inboard flange at the spindle. They don't move very well absent any rotation; at least a little rotation is needed, even if only turned by hand.

There's a retaining circlip holding the cast iron yoke (with bearing) to the hub of the inboard flange. You might try prying the yoke with a crow bar aginst the spindle housing, accompanied by foul language, in as many positions as possible.

In the event, I had to shatter the inboard flange, and complete demolition by drilling many holes through the hub, parallel to the spindle shaft, before I could persuade it to escape. I used a long (~12") bit to reach the hub. The replacement pulley is in the background.

Luckily, I have a second copy of the lathe, and I swapped headstocks to keep turning, even though tailstock alignment went into the weeds. I've also replaced the screws holding the headstock cover with wing bolts, to facilitate lubrication. Don Garlits (American drag racing hero) said, "Oil is the cheapest thing we've got. Use plenty of it."

As near as I can tell, these lathes are all clones, and parts may be interchangeable - might even use the same part numbers.

Best of luck,
Joe

Joe said.....

Fuzzie says ... Oh dear . Looks like my problem. Get a bigger hammer.

Well a bigger hammer didn't workout all that well. I managed to split the pulley side off the arbour sleeve and it slid merrily off the shaft while the yoke part kept clinging on. I wasn't keen on Joe's drill it out approach and thought it looked like a gear puller might now fit around the yoke so I stopped in at the local steering and suspension shop and the friendly guy there helped out. ( I've retyped the last sentence three times and each one reads worse than the last . A picture will have to suffice )

I have now found the tailstock arbour is also frozen. I'm not sure this lathe is worth the effort. A new pulley is going to cost around $60, but if I can't get the tailstock working, there's not much point.

Originally Posted by Fuzzie

Well a bigger hammer didn't workout all that well. I managed to split the pulley side off the arbour sleeve and it slid merrily off the shaft while the yoke part kept clinging on. I wasn't keen on Joe's drill it out approach and thought it looked like a gear puller might now fit around the yoke so I stopped in at the local steering and suspension shop and the friendly guy there helped out. ( I've retyped the last sentence three times and each one reads worse than the last . A picture will have to suffice )

I have now found the tailstock arbour is also frozen. I'm not sure this lathe is worth the effort. A new pulley is going to cost around $60, but if I can't get the tailstock working, there's not much point.

Fuzzie drop it in some diesel for a day or two, when you take it out slowly work the wheel it might free up. $60 aint bad for a lathe worth $300.

Oh what size shaft and thread as some of these vary.

Fuzzy,

I have just recently picked up 1 of these machines , I did own 1 several years ago, which was a mismatch of parts with the tail stock not aligning with the head stock, but that's another story.

For $60.00 new flanges are cheap, check out GPW in TRADERS WAY in CURRUMBIN, he may have the parts or can get them,

Current new price for your machine is $400+gst, so $60 is cheap.

I agree soak the head stock in DESO for a few days use a larger bar (diameter) and wind the tail stock out fully heat the exterior with an lp gas torch then drift the MT2 out carefully , if the live center is still on the end beaware that the center point is seperate and held in with a grub screw,.

They are a reasonable machine and worth a bit of time and tlc to get right, my last 1 I had for 6years with little in the way of trouble, just keep the lubrication up to the shafts .

Jeff

Hi Jeff,

I tried Gary Pye, being the closest to me local source, and Carbatec for spares but neither had a headstock pulley in stock and estimates for availability were some weeks/months away.

In the meantime I have derusted and unfrozen all the parts that aren't broken and as far as I can tell without the headstock pulley, all should be operating reasonably smoothly now. I've also made it a mobile base using some cheap castors so I can shoehorn it into my garage space.

As it happens I will be in the States next month and I should be able to pick up spare parts there. Looking around for a possible source of spares I note the Harbor Freight price for a similar clone is $250. I guess I could bring home a complete one for spares but it might kill the excess baggage charges

Cheers, Franklin

Originally Posted by Fuzzie

Hi Jeff,

I tried Gary Pye, being the closest to me local source, and Carbatec for spares but neither had a headstock pulley in stock and estimates for availability were some weeks/months away.

In the meantime I have derusted and unfrozen all the parts that aren't broken and as far as I can tell without the headstock pulley, all should be operating reasonably smoothly now. I've also made it a mobile base using some cheap castors so I can shoehorn it into my garage space.

As it happens I will be in the States next month and I should be able to pick up spare parts there. Looking around for a possible source of spares I note the Harbor Freight price for a similar clone is $250. I guess I could bring home a complete one for spares but it might kill the excess baggage charges

Cheers, Franklin

Part way down the page of the link, click the tab for "Product Manual" and download. Near the end of the manual, there's a parts list and exploded assembly diagram.

If you know where you'll be in about a week or two, consider ordering the parts from HF for delivery to your US address. A lot less excess baggage. They generally use UPS from either Camarillo CA or Dillon SC. Residential or business address should be OK, definitely not a PO box; unsure about hotels because of temporary situation. I don't think Dillon has over-the-counter parts sales, unsure about Camarillo.

Note the US version has 1"x8 spindle thread, which may or may not be significant.

In any event, you might be pleasantly surprised by the prices. Faceplates are almost a gift, when/if they're in stock.

Cheers,
Joe

Hi Joe,

Thanks for the info. I'm ending up in Houston for a quilt show my wife wants to visit and I was originally hoping Harbor Freight would ship to one of their stores there for pickup, but alas they will only ship to customer addresses. I also wouldn't have a lot of faith in shipping to a hotel suite so I've made contact with pen maker extraordinaire edblysard from Houston who has kindly agreed to help. We are actually driving from Washington DC to Houston via New Orleans.

You're right about the price, but I didn't want to bang on about it, $18 there vs $60 here. I'll check dimensions before ordering.

Cheers,
Franklin

Did you check Hare & Forbes Archerfield/

Originally Posted by vk4

did you check hare & forbes archerfield/

$18?

Well I just got back from my trip to the US with my $18 replacement pulley in hand, but I'm disappointed to report it is not quite the right match for my MC900.

Harbor Freight delivered the pulley via normal post to Ed in Houston who kindly played post box for me. There was no packaging to speak of just the two pulley halves clanking away in an oversize envelope. I had over estimated HF as a tool company. I had thought HF was possibly similar to a Hare and Forbes type company, but the reality on visiting one of their stores is that they are more like SuperCheap Auto here rather than a machinery house. Most of the machinery on the floor looked pretty flimsy, but the MC900 clone was probably the pick of the heap in quality.

Unfortunately the pulley I received is a slightly different casting. The collar that fits into the cast iron push block is much thicker on the new piece. I suppose It's just possible a different bearing could be found to fit the collar and push block, but the arbor size is just a tweak different as well. As near as I can measure the shaft size for the new pulley is 0.8mm (1/32 inch?) smaller than my spindle. I'm guessing that could be reamed out but I'm thinking a suitable replacement bearing might be harder to locate. I'm not sure what tool one would use to ream out the hole for the drive shaft and my ability to accurately measure arbor sizes is obviously suspect .

The pic shows old and new pulleys side by side. So close but yet so far.......