2nd Shopsmith suggestions??

[mbcabinetmaker]

(Quote by Bill)

The quadrant is the next major problem area but most times, it is the lack of oil in the control sheave that caused the quadrant teeth to wear excessively or break. I find that replacing the quadrant roll pin with a 2 1/2" #10 allen head bolt, star washers and locking nut helps keep the quadrant teeth from wearing excessively. I have pictures of this change if anyone is interested.

Bill I would like to see this process and have been trying to send you a PM with my email address as I am not wild about posting it on the forum. The PM system seems to be on the fritz. Is it possible to post these pictures on this thread. Thanks for all that you do to help us keep our machines in top notch shape.

[billmayo]

(Quote by Bill)

The quadrant is the next major problem area but most times, it is the lack of oil in the control sheave that caused the quadrant teeth to wear excessively or break. I find that replacing the quadrant roll pin with a 2 1/2" #10 allen head bolt, star washers and locking nut helps keep the quadrant teeth from wearing excessively. I have pictures of this change if anyone is interested.

Bill I would like to see this process and have been trying to send you a PM with my email address as I am not wild about posting it on the forum. The PM system seems to be on the fritz. Is it possible to post these pictures on this thread. Thanks for all that you do to help us keep our machines in top notch shape.

OK, this a a short history of what I do:

The Speed Control Assembly is the one part that I have to repair on most of the headstocks that I rebuild or repair. Going from SLOW to FAST, the Control sheave is opening putting no pressure on the quadrant. It is when going from FAST to SLOW that the drive belt is being compress and putting pressure on the quadrant and one leg of the bracket. The quicker the Speed Control Handle is turned, the more pressure is causing the leg to bend (716 &717). [ATTACH][ATTACH]5386[/ATTACH][/ATTACH]This pressure will alsoincrease if the control sheave has not been oiled in a long time. If the motor is not operating, you can break the quadrant, bracket leg and/or break the quadrant teeth off. Once the leg starts to bend, then the worm control gear begins to misalign and bind. This takes more effort to turn the Speed Control Handle and puts more pressure on the leg causing it to bend a little more. This causes the quadrant teeth to bind more with the worm gear causing more teeth wear on one side of the teeth. It will quickly destroys the quadrant teeth to where you can not longer use the full speed range. Most of the time, I have to install a new quadrant as the teeth are too worn to reuse.

Being an old farm boy who had to improvise, I believed replacing the roll pin (the edge of the roll pin acts like a dull drill bit) with a solid surface bolt and using the hole in the quadrant (3 times more material) vs legs as a pivot point, I could eliminate most of the wear and help prevent some misalignment. Preventing the one leg from bending helps prevent the main misalignment problem. I found an allen head #10-32 X 2 1/2" bolt (757)[ATTACH]5388[/ATTACH] fits the quadrant hole really good with a star washer on each side of the legs and a locking nut. I use a little bit of wheel bearing grease inside the quadrant hole before installing the bolt. I cut the extra length of the bolt off. The star washer tips helps prevent the bolt from turning. I used red LocTite on the star washers to help secure them. I straighten the bent leg back to its original position being careful not to break the leg (many small hits with a small hammer). You can see in (0758)[ATTACH]5387[/ATTACH] that the worm gear is now centered on the quadrant teeth. I have been doing this change for more than 5 years with no returned quadrant problems or for my shopsmiths.

On headstocks with a rectangle access hole for the speed changer, I actually have to file out a small additional area on the top of the access hole near the top left corner for the allen head bolt clearance on the rebuilt Speed Control Assembly. It is easy to see when trying to insert the speed control assembly.

[mbcabinetmaker]

Thanks Bill, I will do this upgrade the next time I service a machine. I have noticed that the last Mark 5 I bought is a lot harder going from fast to slow than my other Shopsmiths. I did a complete cleaning and lubing before putting it into service but did not check the alignment of the quadrant teeth against the gear. I will do that before using it again.

[robinson46176]

Bill, That is absolutely great information and well presented. Thanks.
I will be checking all of my SS's (well, the ones with that speed control) for that.
What is your favored lube for those gear teeth?

[billmayo]

Bill, That is absolutely great information and well presented. Thanks.
I will be checking all of my SS's (well, the ones with that speed control) for that.
What is your favored lube for those gear teeth?

Well, this is an area that I have been trying many different products. I am currently using LPS Force-842 Dry Moly Lubricant which leaves a nice finish and does not attact sawdust/crud. I really like this product which also leaves a nice metalic looking finish on any cleaned metal like arbors, shafts, lathe tools, joiner/planer knives, wrenches, etc that seems to prevent any rusting for a while. I find any type of grease/oil attracts too much sawdust/crud over time. I have not tried any kind of graphite as it is hard to keep off or get off my hands and I believe Shopsmith did not recommend it's use at one time. I find that any product that collects sawdust/crud may be doing more damage than no lubricant on the teeth.