I have a mark 5 that I use quite a bit and I recently purchased another one at a yard sale for my father-in-law. We got it for a song with a bunch of attachments and then I realized after working with it that the speed control is all messed up.
After breaking it open I think I know what is wrong, but not sure how to fix it. The sheaves on the motor would not open up and after using a puller I was able to get the floating sheave off. I cleaned that whole section up and now it slides well, however when the floating sheave comes close the the fan sheave they seem to lock in place. It looks like the teeth are mating to close and it is friction fitting together. As soon as I try to load the spring on the sheave they lock pretty hard. Looking at the shaft and keys I don't see an easy way to rotate the bits to get them to fit better. I was thinking of buying another sheave but maybe there is a better way? I have a metal lathe and am up for a challenge if someone has an idea. I didn't want to break the pulley from the shaft if it is pressed on, unless that is the only way... Maybe I can rotate the fan sheave?
I also noticed that the speed control arm may not be right on the top knob. The top sheaves move fine but is the spring clip thing supposed to attach to the control sheave? The worm gear and piece are all fine and no broken teeth but they are not attached to anything, it just moves in and out.
When I put it back together, should I lube those control gears with a grease... they are pretty dry.
I was going to pull my working one apart but I hope I can get answers instead as I don't want two broken machines
Ericthet wrote:I have a mark 5 that I use quite a bit and I recently purchased another one at a yard sale for my father-in-law. We got it for a song with a bunch of attachments and then I realized after working with it that the speed control is all messed up.
After breaking it open I think I know what is wrong, but not sure how to fix it. The sheaves on the motor would not open up and after using a puller I was able to get the floating sheave off. I cleaned that whole section up and now it slides well, however when the floating sheave comes close the the fan sheave they seem to lock in place. It looks like the teeth are mating to close and it is friction fitting together. As soon as I try to load the spring on the sheave they lock pretty hard. Looking at the shaft and keys I don't see an easy way to rotate the bits to get them to fit better. I was thinking of buying another sheave but maybe there is a better way? I have a metal lathe and am up for a challenge if someone has an idea. I didn't want to break the pulley from the shaft if it is pressed on, unless that is the only way... Maybe I can rotate the fan sheave?
Both sheaves are keyed to the shaft. The fan sheave has a set screw over the key(very tight). Is the key worn and/or the keyway in the floating sheave worn thus allowing the floating sheave to misalign? It is possible the wheelpuller bent the floating sheave.
I also noticed that the speed control arm may not be right on the top knob.????? The top sheaves move fine but is the spring clip thing supposed to attach to the control sheave? YES There should be a wire(etc.) clip that is attached to the small bearing in the nose of the control sheave that slips over the flat spring clip on the pork chop The worm gear and piece are all fine and no broken teeth but they are not attached to anything, it just moves in and out.
When I put it back together, should I lube those control gears with a grease... they are pretty dry. YES
I was going to pull my working one apart but I hope I can get answers instead as I don't want two broken machines
Thanks!
Eric
Judicious filing of the interfering vanes may be possible.
Mount the floating sheave on that lathe and check for bent/wobble using the 5/8" bore. Does the floating sheave backlash on the motor shaft/key?
╔═══╗
╟JPG ╢
╚═══╝
Goldie(Bought New SN 377425)/4" jointer/6" beltsander/12" planer/stripsander/bandsaw/powerstation /Scroll saw/Jig saw /Craftsman 10" ras/Craftsman 6" thicknessplaner/ Dayton10"tablesaw(restoredfromneighborstrashpile)/ Mark VII restoration in 'progress'/ 10E[/size](SN E3779) restoration in progress, a 510 on the back burner and a growing pile of items to be eventually returned to useful life. - aka Red Grange
The quadrant assembly looks damaged and there is no clip on the control sheave. That all looks damaged, probably busted when the bottom sheaves stuck and someone wrenched on the speed control.
I don't think the floating sheave got damaged. It didn't take much force to pull but I will check as suggested. I was able to get the set screw loose but the fan sheave is stuck like a mother. I worked it about 1/2in but tired for tonight. Letting it sit with some liquid wrench and will try more tomorrow. I did get the key out and it is not too bad. It does appear the surfaces of the fan sheave vanes are wrong. Some of the ends are a bit mushroomed. It is not horrible but might be the cause of the sticking.
Plan is to get the fan sheave off, clean both up then dye and try to see what is rubbing. The key, keyways, and shafts all seem pretty good. I will try to take a picture tomorrow. Also might pull the good ss up to take a look at alignment. Hard to picture for me since I haven't seen the mechanism fully in a working state
The bearing on the nose of the control sheave has a button staked in the center race with a hole through it (sides of the button). A roll pin is a loose fit in that hole. The clip ends fit into the center of the roll pin.
The clip has a wire wound sleeve. That sleeve slips over the flat spring on the quadrant arm. The purpose of the clip is to prevent the center race of the bearing from rotating. However if the floating sheave becomes stuck or sluggish, the quadrant arm will pull on the clip. That us what causes the clip/bearing to get pulled out. Everything goes south following that.
The face of the button normally rides on the steel surface on the quadrant arm(that is what is likely damaged). Often the button/bearing falls out and the end of the control sheave nose scars the quadrant arm surface(and vice versa).
I believe you will find the missing parts in the bottom of the motor pan.
Curious what might have caused the mushrooming???
Some pix would help!
The fan sheave can get frozen on the shaft. Heat to the sheave may help. If you got it to move 1/2" the worst is over. Look for scaring/damage to the shaft around the keyway edges.
╔═══╗
╟JPG ╢
╚═══╝
Goldie(Bought New SN 377425)/4" jointer/6" beltsander/12" planer/stripsander/bandsaw/powerstation /Scroll saw/Jig saw /Craftsman 10" ras/Craftsman 6" thicknessplaner/ Dayton10"tablesaw(restoredfromneighborstrashpile)/ Mark VII restoration in 'progress'/ 10E[/size](SN E3779) restoration in progress, a 510 on the back burner and a growing pile of items to be eventually returned to useful life. - aka Red Grange
JPG wrote:The clip has a wire wound sleeve. That sleeve slips over the flat spring on the quadrant arm. The purpose of the clip is to prevent the center race of the bearing from rotating.
SS 500(09/1980), DC3300, jointer, bandsaw, belt sander, Strip Sander, drum sanders,molder, dado, biscuit joiner, universal lathe tool rest, Oneway talon chuck, router bits & chucks and a De Walt 735 planer,a #5,#6, block planes. ALL in a 100 square foot shop. .
.
Bob
I think these guys, surprisingly, missed the spacer that fits on the motor shaft. Part no.504205 - cost $1.96.
If the spacer has been hit too many times is will be shorter and allow the movable sheave to interlock with the motor sheave. This spacer looks like a wide, cheap wedding band worn by a giant. Memory recalls it is about 5/8" wide.
Octogenarian's have an earned right to be a curmudgeon.
Chuck in Lancaster, CA
charlese wrote:I think these guys, surprisingly, missed the spacer that fits on the motor shaft. Part no.504205 - cost $1.96.
If the spacer has been hit too many times is will be shorter and allow the movable sheave to interlock with the motor sheave. This spacer looks like a wide, cheap wedding band worn by a giant. Memory recalls it is about 5/8" wide.
It goes behind the fan sheave, not between the fan sheave and floating sheave.
It spaces the fan sheave away from the motor end cap.
╔═══╗
╟JPG ╢
╚═══╝
Goldie(Bought New SN 377425)/4" jointer/6" beltsander/12" planer/stripsander/bandsaw/powerstation /Scroll saw/Jig saw /Craftsman 10" ras/Craftsman 6" thicknessplaner/ Dayton10"tablesaw(restoredfromneighborstrashpile)/ Mark VII restoration in 'progress'/ 10E[/size](SN E3779) restoration in progress, a 510 on the back burner and a growing pile of items to be eventually returned to useful life. - aka Red Grange
Didn't have much time yesterday but did make some progress. Finally got that fan sheave to pop off. For anyone reading it was a mixture of liquid wrench and slowly prying with large flat head screwdrivers between the motor face and thick pieces of the sheave casting. Working it a bit then rotating the sheave then working it a bit. Once it got a decent gap between the thin metal shield I put two screwdrivers and rested them on the rivets. Applied some heat around the casting and then a little leverage and pop it finally came.
It is not obvious why they are locking. When I put them together they fit well with space to wiggle. When together the key ways seem to line up with little issue. Key way in the motor shaft seems fine as well all the way down. I am going to clean it all up and then see if the alignment issue persists when I put them back on. My only guess is they both slipped slightly and then got stuck in their positions, mix that with a bit of mushroom on the casting and it locks..... at least that is all I got right now. I will have some time Fri/Sat to do a better look and maybe some pics.
Thanks all for the input it is helping to figure this out. The upper speed control is definitely broken. The clip for the control sheave is just hanging on the quadrant and the thin metal piece on the quadrant is damaged. It looks like the bearing blew out and ripped metal off (looks like metal tear on that thin metal piece. When I first opened it I did see some small bearing balls caught in the pan (never a good sign). I think that bearing is blown out but I can't tell until I take it all off.
I might wait to hit the speed control until I put the motor back together.
While the motor pieces are apart any good suggestions on what to clean? There is a decent amount of dust build up on the windings so I am thinking a spray of air and vacuum to clean.
charlese wrote:I think these guys, surprisingly, missed the spacer that fits on the motor shaft. Part no.504205 - cost $1.96.
If the spacer has been hit too many times is will be shorter and allow the movable sheave to interlock with the motor sheave. This spacer looks like a wide, cheap wedding band worn by a giant. Memory recalls it is about 5/8" wide.
It goes behind the fan sheave, not between the fan sheave and floating sheave.
It spaces the fan sheave away from the motor end cap.
Correction accepted. Shouldn't have relied on memory.
Octogenarian's have an earned right to be a curmudgeon.
Chuck in Lancaster, CA
Got a few mins at lunch to break it down a bit. Took out the speed control assembly and that is a sight to behold. Attached some pics and they are interesting. It looks like the bearing was trying to friction weld itself to the quadrant assembly. The steel got blue and it even wore a way into the aluminum casting. All that is left of that poor bearing I found when poking around the headstock some more. The idler shaft got a bit of marring but it is not too bad, I think it will be fine.
Two questions from this:
1.) I noticed the quadrant might be fixable if I rivet a new steel sheet metal to it. Is this worth it or just go for the $27 for a new one. I noticed they might be on back-order.
2.) Is it worth trying to press a new bearing in the sheave (if I could even find a comparable one) or just pay the $56?
I think at this time I have more money than time, which is not to say a lot... but you get the point.
Back on the motor sheaves... Attached some pics there too. They don't look all that bad. You can see the slight damage on the tips of the vanes. I don't know anything on that until I clean the shaft and try to fit them up again. I did take apart my working SS and noticed that when the sheaves fit together they do stick a bit (they don't come that close with the belt in-between) but nowhere near what the broken one was doing. It could be there was still gunk on the shaft and when they came close enough it stuck, but I still did not like the alignment of the vanes.... will see what happens there.
