T20 Band Differences

[Dirtdobber]

Well, the back story is this.  When I bought the machine the plungers stuck unusually far out of the case.  I did't run the machine.  I let it sit for a couple of years or so until I could totally rebuild it.  I am just now finishing the build.  I tore the T20 down and the lining was very thin.  I sent the bands off and had them relined (.040 thick material).  I'm still not happy with the extent to which the plungers stick out of the case, so I tore it back down and am am now trying to get to the bottom of the mystery.  Although I didn't measure it, I would estimate the plungers stuck out of the case at least half an inch with fresh band lining.

[ascaw]

Oh, you had the same bands relined and put back in?  If that is true did you get the same bands back?  It does seem odd that they were fine before but now they are too long.

[Dirtdobber]

Thanks ascaw.  I found an old post from Whipper that gave the factory drum diameter of 6.210 inches.  Mine are within a few thousandths of that.  My bands are too long.  If they were modified due to turning the drums they would be shorter.

I do intend to make at least two calls, and one may do the trick.  RR can probably tell me  what's going on.  The second call would be to Transmission Crafters to see if they ever provide extra thick lining for the bands.  By my calculations, lining thickness of about .100 inches would make up the difference. 

This just seems bizarre.

[ascaw]

I don't know off hand what the drum size is new but is it possible the drums were turned down and the bands that came out of it are for the turned drums?  I know they can be turned down and there are shorter bands for the turned drums.  If you give Richard a call with the drum sizes and the band lengths (both the old and new) he may be able to tell you what is going on.

Let us know what you find out.

[Dirtdobber]

Thanks for the response WFO.  I have given some thought to the possibility of stretching,  I measured two other of my "long" bands and they are all exactly the same length.  If stretching is what created the extra inch of length, surely they would not have all stretched exactly the same.

[WFO]

    the metal part of the band is stretched too far. better get new bands. I bought mine from Richard. new thicker metal and newer style band material. the plunger sits just inside the bore.

[Dirtdobber]

Hey guys.  I need help with some info.  I have a T20 that I built and installed newly relined bands (0.040" lining).  The plungers stuck out of the case more than they should so I tore it back down.  I found that the bands are 1 inch longer compared to an old set I have.  I measured along the outer band circumference from eye to eye.

Why the big difference in length?  Was there ever a time when the T20 bands had substantially thicker linings and thus the additional length?  By the way, my drums are ok - all 6.204 inches or larger in diameter.

I've got to decide whether to get them relined with thicker lining, or look for new bands.

Thanks in advance for your insight.