SPTclamp adjustment.

[JPG]

I have posted this before(God only knows where), so I will repeat it with a 'findable' title(notice no space between SPT and clamp).

A wobbly bandsaw thread is what prompted me to do this. I will link to this thread from there.

So;

Remove the clamp completely by rotating the 'barrel' until the screws in the ends allow it to be slid out.

Run the screws all the way into the barrel(one end will be left hand threaded)

Next back the screws out about 1-2 turns(enough so the slots in the end castings will 'capture' them, but not so much as to cause interference).

Slide this back into the slots and rotate the barrel so the screws are being extended into the spt mount bores(if the rotation direction is bass-ackwards[subject to opinion*]) back up and reverse end for end and resume.

This will assure that there will be equal clamping at both ends and clearance of the barrel at both ends. The clamping is accomplished by the distance between the screw ends. If either end of the barrel touches the casting, the clamping will only be effective at the opposite end.

* I prefer the clamping rotation to be outside pulled up. Others prefer the opposite. Whatever floats yer boat!:D

Do make them opposite on opposite ends so that outside pulled up or outside rotated down is the same on both ends. I do hope this does not add to any confusion!!!

[charlese]

Since the SPT clamp's center grip (barrel) is not fixed, I find it is not necessary to even the screws distance to the barrel.

Since one side is left handed thread and the other right, the barrel will move off center one way or the other until the screws equally reach the support tubes of the SPT.

Practically speaking, it would be very difficult to offset the screws enough to jam the barrel into one side of the tailstock and jam. If this is possible, then of course, pressure on the support tubes would be unequal.

[moggymatt]

I just tried that tip and going through the setup, I could not see how it would matter either, and in the end it didn't. The wobble/rocking problem I have is caused by the mounting tubes being ever so slightly loose in the mounts. It allows the band saw to rock in-line with the Mark V frame just enough to make me want to fix it. I picked up some UHMV tape and am going to try that next. The thumping I was getting with the blades I was picking up at the WoodCraft store is all but gone with the new 5/8, 3-4 tooth re-saw blade that just came from Shopsmith. I ran a 1x6 x15" piece of fir through it a little while ago several times at 1/8 thick to see how it would do and I'm hooked. Very consistent and a very good cut.

[algale]

I just tried that tip and going through the setup, I could not see how it would matter either, and in the end it didn't. The wobble/rocking problem I have is caused by the mounting tubes being ever so slightly loose in the mounts. It allows the band saw to rock in-line with the Mark V frame just enough to make me want to fix it. I picked up some UHMV tape and am going to try that next. The thumping I was getting with the blades I was picking up at the WoodCraft store is all but gone with the new 5/8, 3-4 tooth re-saw blade that just came from Shopsmith. I ran a 1x6 x15" piece of fir through it a little while ago several times at 1/8 thick to see how it would do and I'm hooked. Very consistent and a very good cut.

1. That is an excellent blade. When I use mine it does not leave the usual telltale stripes that other band saw blades leave.

2. I get the same rocking motion as you with my band saw. Adjusting the clamp does nothing for me either. I will be interested if you find a fix.

[wrmnfzy]

Doing the adjustment worked for me an got rid of some wobble.

[moggymatt]

OK, Don't add a strip of anything to the post!

I tried the UHMV and all it did was wedge itself in there tight. I don't think any thickness would work as the adhesive is what failed. After that I tried two layers of painters tape and it was a tighter fit but still rocked. My digital calipers say the difference is .004.
When pushed towards the headstock, the BS table is more in line with the table saw table. Pulled back and the BS table angles more upward.
I'm thinking of drilling and taping a hole for a nylon bolt 1/2" -3/4" down from the top of the mount. I'll try that tomorrow.

[skou]

Since the SPT clamp's center grip (barrel) is not fixed, I find it is not necessary to even the screws distance to the barrel.

Since one side is left handed thread and the other right, the barrel will move off center one way or the other until the screws equally reach the support tubes of the SPT.

Practically speaking, it would be very difficult to offset the screws enough to jam the barrel into one side of the tailstock and jam. If this is possible, then of course, pressure on the support tubes would be unequal.

I just went out and checked the looseness of the barrel on my ponytail headrest SPT clamp. I've got slightly more than 1/8th inch of sideways motion on the barrel, with nothing mounted.

I'm thinking, if, with an SPT mounted, if the barrel isn't touching either side, there is no issue. BUT, if the barrel is up against either tube, it's only putting pressure on one SPT mount tube. 3 or 4 turns on one of the the screws would easily cause that.

JPG, this is something to look into, if you have a loose SPT. It may not be the only cause, though.

steve

[JPG]

Hoookay. Looked at this on my Goldie and I believe the 'need' to be picky depends upon the version of the hardware one has.

I said 1-2 turns above as a starting point because that was what I remember from working with my 510.

With the Goldie, that is not necessary, nor possible. Start with the two screws barely off the jam point. The casting is narrow enough to work from there. The difference between the ends of the clamp and the casting 'socket is very close. So close that it only takes about 3/4 turn difference between the screws to cause one sided clamping. This is more easily observed by inserting spt mounting tubes that are not connected to each other. I used two tail stocks(they are small and 'light'). So for my Goldie the procedure needs to be start with the bolts essentially run all the way in and back one out until the flats align for insertion into the casting(< 1/4 turn). Observe the clearance on each end when 'clamping'. If a noticable difference, take it out and back out the bolt on the 'close' end(very small - 1/4 turn). The reason for the last tweak is due to dimensional differences between the bore surface and the casting where the clamp bears against.

I could not measure the casting spacing accurately, but a rough attempt places it at about 4 3/4". The clamp end to end is 4.735. The screw pitch is 0.055. So about 3/4 turn will remove the slop to one end.

I will get and look at the later vintage stuff tomorrow.

FWIW, the need for this pickyness was 'discovered' a long time ago.

If the later hardware is less close, it becomes less picky.


In any event, I suggest equal clearance on each end of the clamp to the casting when clamping both SPT mounting tubes is the objective to assure both tubes are wedged in place by the clamp.

Tubes loose in the thing being mounted is a different issue entirely.

[Ed in Tampa]

Interesting you mentioning the direction to tighten the barrel.

I'm told on Shopsmith demo machines each demo'er was taught to switch the barrels around until both tightened with a upward movement on the outside of the barrel. That way they didn't have to think about which way to turn when doing a demo.

I was also told the great prank between demo'ers was to switch the barrel around so the expected upward movement would actually loosen. As told to me this was something SS demo'er did to each other constantly through out the years. I guess it made for more than one embarrassed demo'er to mount the bandsaw and go to tighten it down only to have the barrel drop on the floor. Of course the old pro's who had it happen to them so often knew almost instantly that someone switched the barrels around.

["Wild Bad Bob"]

Ed,
glad you pointed that out. I am always confused, which is easy for me LOL, which way to turn that darn thing. I am glad I am not the only one. Here is how I solved the problem, have 6 SS!!! Just dedicate each one for something or 2, and that took care of changing SPTs!!!!!!!!