Headstock slide lock doesn't work

billmayo · Post by **billmayo** » Fri Sep 07, 2012 12:20 am

The headstock lock rod is steel and the wedges are aluminum so it is very easy to overtighten the headstock lock handle and damage the threads in the wedges. Should only take a turn or less to lock and unlock the headstock if adjusted properly. I find the wedge angle needs to be refilled on most headstocks I repair to insure good locking.

lightnin · Post by **lightnin** » Sat Sep 08, 2012 10:48 am

Before cutting the rod look and see if it has become available.
Part 80 here

dusty · Post by **dusty** » Sat Sep 08, 2012 11:39 am

lightnin wrote:Before cutting the rod look and see if it has become available.
Part 80 here

That link indicates to me that the rod is not available as a part. If needed, the assembly that includes the rod and wedges must be ordered. Not cool!!

lightnin · Post by **lightnin** » Sun Sep 09, 2012 3:34 am

dusty wrote:That link indicates to me that the rod is not available as a part. If needed, the assembly that includes the rod and wedges must be ordered. Not cool!!

I suppose if I had to cut the rod to get it out I would be thinking the wedge locks threads have been stressed and would like to replace them to.

JPG · Post by **JPG** » Mon Sep 10, 2012 2:18 pm

lightnin wrote:I suppose if I had to cut the rod to get it out I would be thinking the wedge locks threads have been stressed and would like to replace them to.

It is the shearing of the wedge threads that causes the 'jamming'. The wedges are softer than the rod. Before cutting the rod, I would try destructive removal of the offending wedge. Yes access is an 'issue'!:D Remove the wingnut and tension pin first. Apply torque to the rod from the unthreaded center.

backhertz · Post by **backhertz** » Mon Sep 10, 2012 3:25 pm

I just looked & didn't see part #80 for the rod listed. Perhaps it might be easy to make a new one? Although it looks like an entire assy is available as p/n 513014 for $23.21 and I also see the wedge locks for $8.95 a piece.

I am wondering if there is a way to simply remove a suspect aluminum wedge lock without damaging the steel rod? I've never had a problem myself & found the removal of the rod to be simple when doing a DVR upgrade once I pushed out the rollpin.

The hardest part was simply keeping the wedge locks in position so the headstock could be slid back on. That should be a one person job, but my back tells me otherwise.... I found using cardboard tubes makes it a piece of cake by keeping the wedges in position.

I know in the DVR upgrade DVD, Jim mentions to cut the rod if there is a problem. But is there an easier way as JPG below (above) suggests?

JPG · Post by **JPG** » Mon Sep 10, 2012 6:08 pm

backhertz wrote:I just looked & didn't see part #80 for the rod listed. Perhaps it might be easy to make a new one? Although it looks like an entire assy is available as p/n 513014 for $23.21 and I also see the wedge locks for $8.95 a piece.

I am wondering if there is a way to simply remove a suspect aluminum wedge lock without damaging the steel rod? I've never had a problem myself & found the removal of the rod to be simple when doing a DVR upgrade once I pushed out the rollpin.

The hardest part was simply keeping the wedge locks in position so the headstock could be slid back on. That should be a one person job, but my back tells me otherwise.... I found using cardboard tubes makes it a piece of cake by keeping the wedges in position.

I know in the DVR upgrade DVD, Jim mentions to cut the rod if there is a problem. But is there an easier way as JPG below (above) suggests?

I do not recall using the word 'easy'!;)

backhertz · Post by **backhertz** » Mon Sep 10, 2012 10:40 pm

Oh, neither did I. It was a question. I have a few headstocks down in my basement, let me take a look. I just posted a pic. If the wedge is stripped or galled, all I can say is oh boy. It is going to be a major operation, i.e. remove the motor etc.

It looks though that the wedge could be maybe cut off with a Dremel tool, pried off & hopefully the steel thread will be okay. I hope the word lucky might be used and one of the wedges spins & allows you to get to the bad wedge....

JPG, I believe your method is the one to try. Good luck.

billmayo · Post by **billmayo** » Mon Sep 10, 2012 11:12 pm

I normally only find one wedge that is seized to the lock rod. Remove the lock handle. I remove the motor/motor pan and then, the headstock from the way tubes. Turn the freed wedge all the way to the center of the lock rod. Then, you can remove the wedges and lock rod from the headstock. Remove the freed wedge from the lock rod. I put the center of the lock rod in a metal vise and using vise grips or a pipe wrench, attempt to remove the seized wedge from the lock rod. If successful, I find I can reuse the lock rod after cleaning the aluminum remains from the threads. This works about 90-95% of the time for me.

backhertz · Post by **backhertz** » Tue Sep 11, 2012 2:15 am

Bill,
I was hoping you'd share your experience & wisdom. I only checked 3 headstocks and found 6 wedges all essentially loose on 3 rods- not a tight fit at all on any of them. I can't imagine needing to torque the wedges all that much to hold the headstock in place- even with a heavier DVR motor in the vertical position. I'm wondering if the loose fit wedge/rod is by design or a sign of wear? Perhaps that coupled with excessive torque or the lack of any lube with any or all the above contributes to the problem on a 30 or so year old headstock. Do you replace many wedges? I can't see how and wood or metal chips might sneak in above the motor, but never-the-less there is usually a lot to blow out when I pull a belt cover off of headstocks that I don't think have ever had the sheaves lubricated.

I took my headstocks apart 4 years ago and bought all new parts- bearings, belts, idler shafts, speed assy, etc to upgrade 3 headstocks to new condition when I though Shopsmith might bite the bullet. Then Shopsmith like the Phoenix of myth, flew out of the fire and changed the idler shaft assembly with two bearings (the old one reminded me of a water pump bearing) and then the new DVR motor. A new ball game! I never even thought to replace the wedges.

But even with the new motor which requires the rod and wedges removed and a spiral wrap put around the rod, the rod is never lubricated or inspected as part of the upgrade procedure. I've only done two DVR motor upgrades. The only problem I've had with the wedges is keeping them in place as I & a helper put the headstock back on the way tubes. But the secret to that is a 1 3/4" paper tube and the tubes fit first time, every time. I think the wrap is primarily to prevent any wear on the wires that might touch it. But perhaps some lube/corrosion prevention lube might help too.

I wonder how tight a wedge is suppose to fit on the threaded rod? I have used all ones, and never thought to ever replace them. I just noticed the rod & wedge are on the list of 17 most replaced parts. But they were not part of the almost total headstock rebuild kit supplied with the PowerPro motor. Since Shopsmith didn't include it in the DIY kit, I imagine the Shopsmith policy must be as needed.

I'm an old preventive maintenance trained retired military technician. We didn't wait for things to break. If we had a huge assy apart, it got all new parts if there was a chance of a failure down the road. I wonder if it would simply be good preventive maintenance to replace just the wedges- just like it is when changing the timing belt on a Honda Civic motor. Honda recommends changing out the water pump at that time- even if nothing is wrong as a person essentially only has a few bolts more remove to replace the water pump being everything else is already off. The labor is excessive and everything is already apart. I don't see the rod wearing. Just a thought/question?

I just reread the entire thread & noticed Dusty pretty much outlined the same thing you just mentioned Bill.

Hoping the waters have subsided & you have a back yard again.

Tony