520 carriage lock wedges

[DLB]

Just wanting to drop back to my previous point. Sorry for any confusion. I didn't suggest they were not Shopsmith Wedge Locks. They almost certainly are. But they are not 520 Carriage Wedge Locks (514095).

- David

[RFGuy]

Just wanting to drop back to my previous point. Sorry for any confusion. I didn't suggest they were not Shopsmith Wedge Locks. They almost certainly are. But they are not 520 Carriage Wedge Locks (514095).

- David

Thanks David for pointing this out because that was not readily apparent to me. Do you know what is different about the 520 wedge locks versus the other SKU number? Did something change in the headstock casting or carriage lock assembly during manufacturing? Or is it something changed to support the PowerPro?

I don't understand why the 520 specifically has to have a different wedge lock than the 510 for instance.

[edma194]

Just wanting to drop back to my previous point. Sorry for any confusion. I didn't suggest they were not Shopsmith Wedge Locks. They almost certainly are. But they are not 520 Carriage Wedge Locks (514095).

- David

514095 is listed as simply a wedge lock, don't know what it is. The parts for all models are 504234 (Right Hand Wedge Lock) and 504235 (Left Hand Wedge Lock).

I know it says those wedge locks are for 505/510/520 machines with no mention of 500s, but the conventional headstock diagram shows those parts and they should work on a 500 just as well. Just to be sure I'll go take a look at a 500 locking mechanism later on.

[DLB]

Just wanting to drop back to my previous point. Sorry for any confusion. I didn't suggest they were not Shopsmith Wedge Locks. They almost certainly are. But they are not 520 Carriage Wedge Locks (514095).

- David

Thanks David for pointing this out because that was not readily apparent to me. Do you know what is different about the 520 wedge locks versus the other SKU number? Did something change in the headstock casting or carriage lock assembly during manufacturing? Or is it something changed to support the PowerPro?

I don't understand why the 520 specifically has to have a different wedge lock than the 510 for instance.

It's the same ones for the 505/510/520/M7 Carriage. Different than ANY headstock and different than 500 and prior carriage (which are the same as headstock). I didn't mean to imply it was 520 unique. My original post was intended only to help the OP not buy headstock wedge locks when he clearly wanted carriage wedge locks.

- David

[edma194]

504234 and 504235 are also listed as the wedge locks for a 500 carriage. I do not see why they wouldn't work on a 500 carriage or headstock.

[wurlitzerwilly]

Is this only a problem on the carriage? Very easy to take a look at those wedge locks in drill press mode and see what keeps the carriage from moving. You can probably disassemble the locking mechanism without removing the carriage. The screws rust easily but are fairly hard steel and don't rot away easily. Gunk can build up in the threads of the screw or wedges. I use penetrating oil to make sure I can turn the wedges all the way in to remove the screw, and then remove them. De-rust the screw, clean the wedges well, file of any sharp edges and put it back together.

Also, when I remember, putting penetrating oil on the roll pin holding the handle on helps it come out nice and easy. Not sure if helps driving the pin back in. That little trick I should have learned years ago makes me hate roll pins less.

You know I must be getting too old - it just doesn't dawn on me to use drill press mode to view the underside of the carriage. Thanks for mentioning that. No problem with the rust - I have rust remover gel and wire brushes. I guess the roll pin needs to be removed in order to be able to turn the screw shaft more than the usual 3/4 turn. I used to use those pins a lot and I think I still have the roll pin fitting tool.

I'll let you know how I get on, probably over the weekend.

[JPG]

The wedges wear at the contact point of the wedges to the way tubes. The sloped shape of the wedges press against the round tubes and the line contact will cause a concave depression on the slope of the wedges. Eventually this wear will result in an over the center situation and create the situation you described. A minimal amount of reducing the concavity of the wear will solve the problem. here is a substantial amount of material in those wedges so the 'fix' can be repeated multiple times.

The gorilla factor will increase the wear.

Yes removing them makes this 'dressing' them much easier.

[RFGuy]

It's the same ones for the 505/510/520/M7 Carriage. Different than ANY headstock and different than 500 and prior carriage (which are the same as headstock). I didn't mean to imply it was 520 unique. My original post was intended only to help the OP not buy headstock wedge locks when he clearly wanted carriage wedge locks.

- David

David,

Thanks. Sorry for any confusion. When I first read your reply I guess I misunderstood it. Thanks for clearing this up and pointing out the differences.

[wurlitzerwilly]

Hi again guys.

I have everything sorted out now, but there were some mysteries.

I put the SS into drill press mode and locked it. I then removed the nut on the backside of the carriage lock and removed the washer and wedge. Unlike some images I've seen, the spring that pushes the wedges away from the way tubes is a single spring which runs the length of the shaft, not two separate springs, one at each end.
I had to remove the table raise/lower wheel, so that the carriage lock arm could be fully removed along with the front wedge.
Both wedges are identical and do not have a screw thread to attach to the shaft, which I believe the headstock wedges do.
Both wedges have a "clutch" cutout, but only the front one is used to engage with a clutch collar and engaging ring which has a roll pin through it to attach it securely to the shaft.
I have re-dressed the wedges and used dry silicone spray on all surfaces except where the wedges mate with the way tubes. I also de-rusted the long spring.
Re-assembly was fairly straightforward, but I had to use some grips to hold the spring back from the back end, so that I could get the wedge, washer and nut back on the shaft.
I've adjusted the nut as per the manual and it now locks at the 4 o'clock position without undue force. Loosening the lock, the wedges now spring back away from the way tubes as they should.
The entire carriage assembly is now working as new (or better).

Alan.

[wurlitzerwilly]

Just wanting to drop back to my previous point. Sorry for any confusion. I didn't suggest they were not Shopsmith Wedge Locks. They almost certainly are. But they are not 520 Carriage Wedge Locks (514095).

- David

Thanks David. Now that I've finally had the carriage lock completely disassembled, I agree with you, the wedges in my original photos are definitely *not* carriage lock wedges (well not for my carriage anyway). They are almost certainly headstock wedges.