Drive Hubs/Mounting tubes set up with power pro headstock

rolands · Post by **rolands** » Sat Dec 25, 2010 1:35 pm

Doesn't matter when you became a member. Main thing is you are a member and a lot of information can be gained or given on the board. I for one have found that out. Everyone has been very helpful when I have asked a question and I've gotten my problem solved. Welcome from Colorado.

keakap · Post by **keakap** » Sat Dec 25, 2010 10:27 pm

bobdaun wrote:Just got my new power pro headstock last week and installed it on my 520. One of the things that was mentioned in the instructions is that the horizontal and vertical must be perfectly matched by adjusting the mounting tubes. OK, I mounted my band saw and slid power pro over to it. The hubs did not match with the band saw hub. ...

Bob Daun

Wow, that is weird. I haven't used my band saw on the PP, but the jointer went right on without any adjustment. (Frankly I don't remember seeing any admonition regarding checking the adjustments. Maybe that's a clue.)

I'm looking forward to the answer on this one!

dusty · Post by **dusty** » Tue Feb 28, 2012 4:54 pm

keakap wrote:Wow, that is weird. I haven't used my band saw on the PP, but the jointer went right on without any adjustment. (Frankly I don't remember seeing any admonition regarding checking the adjustments. Maybe that's a clue.)

I'm looking forward to the answer on this one!

All that is really important is that the problems have all been resolved. It would, however, be nice to know whether shaft locations changed in the new PowerPro or was this dilemma caused by something else (alignments). I'd bet my new PowerPro on alignments.

I find that from time to time I need to tweak these same alignments. Positioning secured by a couple set screws is just NOT ABSOLUTE!. The more you move the equipment around or change configurations, the more frequently that re-alignment may be needed.

I also fing that from time to time I need to either replace the set screw (discard the old one) or do some house keeping on the setscrew landing zone. This is especially true with a flat tipped setscrew. It seats best with a smooth surface.

2bits · Post by **2bits** » Tue Feb 28, 2012 7:54 pm

ADDED COMMENTS: Here are some rough measurements from the drive shafts center line to the top surface of the way tubes. The lower shaft is 2 27/32" above the tubes and the upper shaft is 7 5/8" above the tubes. This means the shafts (on center) are 4 25/32" apart.

Someday I may be able to measure a power-Pro and an 83' vintage headstock to compare. I will check the 83' when i go back out to the shop. I will then compare it to the Power-pro (HOPEFULLY SOON

)

JPG · Post by **JPG** » Tue Feb 28, 2012 10:24 pm

What pray tell would cause shaft alignments to change with he power pro. All headstock bores are the same. The only shafting that changes is the idler shaft. The eccentric is still used.

Therein lies the culprit! for the jointer.

Changing the belts with the older drive or adjusting the tension causes changes in the idler shaft alignment to the jointer.

The main shaft alignment will be affected by the tie rod removal and replacing and any twisting of the way tubes caused by headstock removal and replacing.

I do not understand the concern regarding having to readjust the spt tubes.

I would expect it unless the way tubes were re-aligned to the bench tubes etc.!

dusty · Post by **dusty** » Wed Feb 29, 2012 7:01 am

JPG40504 wrote:What pray tell would cause shaft alignments to change with he power pro. All headstock bores are the same. The only shafting that changes is the idler shaft. The eccentric is still used.

Therein lies the culprit! for the jointer.

Changing the belts with the older drive or adjusting the tension causes changes in the idler shaft alignment to the jointer.

The main shaft alignment will be affected by the tie rod removal and replacing and any twisting of the way tubes caused by headstock removal and replacing.

I do not understand the concern regarding having to readjust the spt tubes.

I would expect it unless the way tubes were re-aligned to the bench tubes etc.!

What pray tell could cause shaft alignments to change?

I think the answer to that question is relatively simple. Something moved unexpectedly. And the only thing that I can think of that would allow something to move unexpectedly is to have had a loose setscrew(s).

Most of the setscrews that we are talking about are "flats". Most of the setcrews that we are talking about do not have the nylon patch.

Maybe there needs to be some changes made. Are there technical reasons why these setscrews should not have the nylon patch?

I'm thinking mostly of the hubs and the arbors. These are set screws that seem to be part of an issue with the PowerPro growling at the user if he chooses to use a bandsaw.

These setscrews, as best I can tell, are all the same and do not have the nylon patch (using the Shopsmith parts).

Maybe this part should be used. What say you?

This specific part is longer than the callout but I am unable to find a 1/4" setscrew with the nylon patch.

This is a part equivalent to the Shopsmith part (222458).

Disclaimer: This posting should not be taken as a call for assistance from Engineering. This is, at this time, just a talking point on the forum. It also should not be taken by users as a recommendation to substitute parts. I am not qualified to do that. My only experience in matters such as these is as a engineer for a defense contractor. If you do substitute parts, you are doing so at your own risk. Further side comment: I do currently have a substitute part installed in one of my saw arbors as an "unauthorized" field test.

JPG · Post by **JPG** » Wed Feb 29, 2012 10:30 am

dusty wrote:What pray tell could cause shaft alignments to change?

I think the answer to that question is relatively simple. Something moved unexpectedly. And the only thing that I can think of that would allow something to move unexpectedly is to have had a loose setscrew(s).

Most of the setscrews that we are talking about are "flats". Most of the setcrews that we are talking about do not have the nylon patch.

Maybe there needs to be some changes made. Are there technical reasons why these setscrews should not have the nylon patch?

I'm thinking mostly of the hubs and the arbors. These are set screws that seem to be part of an issue with the PowerPro growling at the user if he chooses to use a bandsaw.

These setscrews, as best I can tell, are all the same and do not have the nylon patch (using the Shopsmith parts).

Maybe this part should be used. What say you?

This specific part is longer than the callout but I am unable to find a 1/4" setscrew with the nylon patch.

This is a part equivalent to the Shopsmith part (222458).

Disclaimer: This posting should not be taken as a call for assistance from Engineering. This is, at this time, just a talking point on the forum. It also should not be taken by users as a recommendation to substitute parts. I am not qualified to do that. My only experience in matters such as these is as a engineer for a defense contractor. If you do substitute parts, you are doing so at your own risk. Further side comment: I do currently have a substitute part installed in one of my saw arbors as an "unauthorized" field test.

My 'what . alignments . change' "question" referred to spt/headstock alignment. Loose set screws will not cause alignment to change(spacing yes). Those bores will not move.]not[/B] involved with setup changes like quill/arbor screws) should be cup or 'knurled' cup type.

A nyloc or nylon patch screw would possibly be helpful, but IMHO if the 'dig in' type set screws are adequately tightened, they rarely come loose due to vibration. The PowerPro may be different due to the possible added torque oscillations. The only places I am aware that that type screw is used on a SS is those that are not intended to be tightened fully(quill/keyway half dog and miter gauge stop screws come to mind).

I do not think there is any reason to not use one other than cost etc. As for length, I believe they should be as long as the hub(or whatever) allows without protruding.(safety!!!!!)

One thing is for sure! When I put the pieces on my PP DIY together, the setscrews shall be well secured prior to powerup!:D

dusty · Post by **dusty** » Wed Feb 29, 2012 2:30 pm

JPG40504 wrote:My 'what . alignments . change' "question" referred to spt/headstock alignment. Loose set screws will not cause alignment to change(spacing yes). Those bores will not move.]not[/B] involved with setup changes like quill/arbor screws) should be cup or 'knurled' cup type.

A nyloc or nylon patch screw would possibly be helpful, but IMHO if the 'dig in' type set screws are adequately tightened, they rarely come loose due to vibration. The PowerPro may be different due to the possible added torque oscillations. The only places I am aware that that type screw is used on a SS is those that are not intended to be tightened fully(quill/keyway half dog and miter gauge stop screws come to mind).

I do not think there is any reason to not use one other than cost etc. As for length, I believe they should be as long as the hub(or whatever) allows without protruding.(safety!!!!!)

One thing is for sure! When I put the pieces on my PP DIY together, the setscrews shall be well secured prior to powerup!:D

In most applications where a setscrew would extend outside of the object into which it is installed, I don't believe that it would be a safety issue BUT it would be useless.

Putting a 3/8" into a 1/4" deep threaded hole leaves 1/3 of the threads exposed doing nothing. That would be the case for saw arbors. What I am saying is that my idea of a longer setscrew (in most applications) would buy me nothing. BAD IDEA Same with the hubs.

JPG · Post by **JPG** » Wed Feb 29, 2012 3:17 pm

dusty wrote:In most applications where a setscrew would extend outside of the object into which it is installed, I don't believe that it would be a safety issue BUT it would be useless.

Putting a 3/8" into a 1/4" deep threaded hole leaves 1/3 of the threads exposed doing nothing. That would be the case for saw arbors. What I am saying is that my idea of a longer setscrew (in most applications) would buy me nothing. BAD IDEA Same with the hubs.

The safety 'issue' has to do with things getting snagged on the protruding screw whole it is rotating.

dusty · Post by **dusty** » Wed Feb 29, 2012 5:05 pm

JPG40504 wrote:The safety 'issue' has to do with things getting snagged on the protruding screw whole it is rotating.

I do understand why some people view this as a safety issue. What I said was that I don't see it that way.

I see hanging a faceplate on the end of the headstock (instead of a hub) as a safety issue.

These are called opinions.