Mark 500....first attempt to use problem

[pieceseeker]

So I go to use my Mark 500 for the first time, going to use the belt sander to reshape the wife's shoe stretchers (2), right?

Well I attach the proper drive hubs up to the sander and the "upper" auxilliary shaft and then attach the power coupler and this is what I get. ( spent a 1/2 hour aligning the shafts)
[ATTACH]20774[/ATTACH]
[ATTACH]20775[/ATTACH]
[ATTACH]20776[/ATTACH]
What is wrong with this picture????

Some observations:

The headstock drive hub is not going all the way into the power coupler.

This cannot be correct.

The setscrew for the headstock drive hub is sticking up too high.

The power coupler's headstock end runs into the setscrew.

Some troubleshooting:

Yes, the setscrew is squarely on the flat part of the shaft.

Yes, the drive hubs are in their proper locations, per the manuals.


Some questions:

Are not all drive hub set screws created equal?

Is there a special shorter setscrew used on 5/8 hole drive hubs??

What gives???


Now, obviously I compared all my drive hub setscrews and they are all the same.
Some of the setscrews used elsewhere on the machine are somewhat longer.

Any insight here would be helpful

[dusty]

So I go to use my Mark 500 for the first time, going to use the belt sander to reshape the wife's shoe stretchers (2), right?

Well I attach the proper drive hubs up to the sander and the "upper" auxilliary shaft and then attach the power coupler and this is what I get. ( spent a 1/2 hour aligning the shafts)
[ATTACH]20774[/ATTACH]
[ATTACH]20775[/ATTACH]
[ATTACH]20776[/ATTACH]
What is wrong with this picture????

Some observations:

The headstock drive hub is not going all the way into the power coupler.

This cannot be correct.

The setscrew for the headstock drive hub is sticking up too high.

The power coupler's headstock end runs into the setscrew.

Some troubleshooting:

Yes, the setscrew is squarely on the flat part of the shaft.

Yes, the drive hubs are in their proper locations, per the manuals.


Some questions:

Are not all drive hub set screws created equal?

Is there a special shorter setscrew used on 5/8 hole drive hubs??

What gives???


Now, obviously I compared all my drive hub setscrews and they are all the same.
Some of the setscrews used elsewhere on the machine are somewhat longer.

Any insight here would be helpful

You need shorter set screws. The vast majority of the setscrews used are 5/16" long.

[ATTACH]20778[/ATTACH]

[pieceseeker]

All of my drive hub setscrews are 5/16 long, all 8 of them.

[dusty]

pieceseeker: I do use a different hub on that shaft than the one you have pictured.

[ATTACH]20779[/ATTACH]

[ATTACH]20780[/ATTACH]

[dusty]

All of my drive hub setscrews are 5/16, all 8 of them.

I don't think this makes a difference (but maybe). Are all your hub setscrews flat points? They should be.

http://www.fastenal.com/web/products/details/25450;jsessionid=vsXbRYQPFqgHNBkF8LyXgLjQ6q1kV9bbW3WqX7Tld52ycF4pmWrp!-840290057!NONE

[reible]

The set-screw in question is 1/4" long flat point.

Ed

[dusty]

The set-screw in question is 1/4" long flat point.

Ed

I am confused. Not on my machines.

[dusty]

I stand corrected. Ed is right.

Now I gotta learn to read my spread sheet.

5/16" is the diameter.

[pieceseeker]

Well then, that has to be the answer. All of my setscrews for the drive hubs are 5/16 long serrated cup points. I have 8 of them.

The real question now is, where is mine? Somewhere on my machine stuck in a hole meant for a longer setscrew?

Without that, the previous owner wouldn't be running anything off of the upper aux shaft.

Here's what I have.
[ATTACH]20781[/ATTACH]
[ATTACH]20782[/ATTACH]
These are the 4 different hubs in my possession. My long hub that go on the headstock looks different than Dusty's. Notice the smooth shoulder that goes on first.

[ATTACH]20783[/ATTACH]
per instructions!
[ATTACH]20784[/ATTACH]

[pieceseeker]

BTW, if all the drive hubs require 1/4 flat point setscrew, where would the 5/16 cup point screws be used? Maybe they don't even belong on a ShopSmith!