Mark VII drive belt.

[zenman]

It seems like the speed dial is too loose onto the springs detents. when I push onto the dial slightly, the spinning stops.

So it looks like this dial really has to be tight.

Since the only ay to tighten it is with that clip, there are some challenges. to punch in on the dial as the clip is installed.

I'll try to cut some shims with delrin to insert between the wave washer and the dial.

[zenman]

Mark VII and a head unit from a second Mark VII for sale!!!!!

The follower sheave has a crunch to the rotation now, so the bearing has issues and the follower just doesn't look like it is square with the cam.

The speed dial has a space of about 1/8 - 1/4" on the right side from the body and I can't seems to get the dial tighter to the base using shims on the center. I used two different dials with the same problems.

It looks like an alignment issue with the non follower sheave on the top. as that one provides a keyed sleave for the sheave with the follower to slide on. Since that is the only original part left to the puzzle here.

Doesn't look like any alignment adjustments. for that sheave/pulley.

This unit never worked, I bought it thinking I could fix this.

The speed dial just isn't designed well.

[JPG]

Alignment of (a) the control knob/cam shaft or/and (b) the idler shaft/control sheave and/or (c) the motor shaft/floating sheave.

'Follower' sheave tis a mystery. I be assuming you mean the control sheave that the speed control cam moves.

If the control knob shaft is causing the knob to be cocked relative to the casting, the shaft bore maybe cocked, but I do not think that is likely. Do the two bullet detents have equal tension/range of motion? The knob is loosey goosey on the shaft. Maybe shimming there? At the flats?

If the control sheave keyway is worn, or the hub bushing is worn, the sheave could get cocked on the idler shaft. Ditto the floating sheave on the motor shaft.

The keys are standard size(3/16???) and replaceable(the kink would need to be added to standard hardware).

You do realize the idler shaft eccentric adjustment(poly-v belt tension) will alter the positioning of the control sheave 'follower' across the cam surface.

What is 'crunching'? Something must be 'interfering'.

Maybe some pix of these alignment issues would help deciphering the cause.

I am not ready to give up on this yet!!!;)

[zenman]

Thanks,

I needed to turn some pens tonight so I swapped the head unit out of this with another Mark VII I bought for $50. I bought four of them. Oddly enough it all involved a death in the family. When I die, someone gets four, well maybe three.

Anyways, that one's rails were really rusty. I swapped out the head unit with the rails from my current setup. Now I have speed that is controlled, hallelujah. However, this one has a motor that only clicks when going in reverse. Crap..

Looking at a working head, I see the follower does not rotate slightly when the motor is on. The bad head, the follower does turn in the rotation of the sheave. So now I am thinking that maybe the eccentricity needs to be adjusted. I will try to adjust it to see is that fixes anything while the head is off of the rails.

If not, I will take the motor off of the bad head and connect it to the top part of the head unit of the fourth unit, and replace the cam and follower sheave from the bad head which originally came from it. Need a spreadsheet I know.

I hope to make a shorty with the remaining parts. Removed the rail support from the stand and cut the tubes already.

This units has a whole bunch of different sized screws. So I think someone has been mucking with it over the years.

Thanks to you, I am not afraid to take it apart, but I won't rebuild it or maybe I am about to.

[JPG]

. . .

Looking at a working head, I see the follower does not rotate slightly when the motor is on. The bad head, the follower does turn in the rotation of the sheave. So now I am thinking that maybe the eccentricity needs to be adjusted. I will try to adjust it to see is that fixes anything while the head is off of the rails.

If not, I will take the motor off of the bad head and connect it to the top part of the head unit of the fourth unit, and replace the cam and follower sheave from the bad head which originally came from it. Need a spreadsheet I know.

. . .

This units has a whole bunch of different sized screws. So I think someone has been mucking with it over the years.

Thanks to you, I am not afraid to take it apart, but I won't rebuild it or maybe I am about to.

The reverse 'click' is likely due to the switch. Orrrr if mucking includes wiring, . . . . . . Does that one have a start relay?

Ya might want to determine why before swapping motor. I doubt the motor itself is the 'problem'.] Beeg ;>}[/B]

[zenman]

thanks,

I oiled the sheaves and I even put a fine layer of synth grease.

on the original head, the bearing on the follower might have been misaligned somehow as it got really hot running at 2500 for a couple of minutes. this was even with the thickest side of the follower up . need to see if my working units have it that way. I will order a 5 pack of sealed skb bearings and replace to see if that fixes the drag. could it be that the bearing could be bad in both of the sheaves?

will check on clicking motor, but it is working. and so much quieter than the umit in question, like you said, a switch or wiring issue. funny, the direction on the unit in question, was reversed when I got it.

back to the speed dial, I am still looking at why the dial turns. I tried shimming one of the three screws jolding the cam support rod, the thing with the spring loaded buttons.i put toothpaste inside the dial to see if that would add friction, but still turns on its own.

Will exchange various components, from two heads, I think the top outer sheave is related, will know maybe tomorrow. gotta write code today.

[JPG]

thanks,

I oiled the sheaves and I even put a fine layer of synth grease.

the bearing on the follower might have been misaligned somehow as it got really hot running at 2500 for a couple of minutes. this was even with the thickest side of the follower up . need to see if my working units have it that way. I will order a 5 pack of sealed skb bearings and replace to see if that fixes the drag. could it be that the bearing could be bad in both of the sheaves?

will check on clicking motor, but it is working. and so much quieter than the umit in question, like you said, a switch or wiring issue. funny, the direction on the unit in question, was reversed when I got it.

back to the speed dial, I am still looking at why the dial turns. I tried shimming one of the three screws jolding the cam support rod, the thing with the spring loaded buttons.i put toothpaste inside the dial to see if that would add friction, but still turns on its own.

Will exchange various components, from two heads, I think the top outer sheave is related, will know maybe tomorrow. gotta write code today.

Avoid spaghetti!


Top Down Top Down Top Down!!!!











Think First, 'code' later.

[zenman]

The replacement Shopsmith Mark VII ran for about 15 minutes, then a high pitched squeal and that was the end of any rotation.

Motor frozen.

I will replace the working motor from the original unit and got one that works.
Hopefully the speed control will work on this combo.

One things I noticed is that on the two working speed dials, the click indentations were all filled with a brown goop, so that only the very edges can be seen. Normally I cleaned them, but this time I will not.

So now I have a real motor that needs to be rebuilt and I can get hose bearings that JPG mentioned.

This one is a GE motor with relay.

So how many Mark VIIs does it take to spin a light bulb. Three.

[JPG]

The replacement Shopsmith Mark VII ran for about 15 minutes, then a high pitched squeal and that was the end of any rotation.

Motor frozen.

I will replace the working motor from the original unit and got one that works.
Hopefully the speed control will work on this combo.

One things I noticed is that on the two working speed dials, the click indentations were all filled with a brown goop, so that only the very edges can be seen. Normally I cleaned them, but this time I will not.

So now I have a real motor that needs to be rebuilt and I can get hose bearings that JPG mentioned. Take lots of pix before disconnecting any wires!!!! Make sure wire colors are visible.

This one is a GE motor with relay.
So how many Mark VIIs does it take to spin a light bulb. Three.

I think the 'brown goop' is likely acupucky (grease with sawdust embeded).

[zenman]

That was placed there or accumulated there?