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DEC ADJUST SCREW MODIFICATIONS

The text and pictures was submitted by Floyd

For those that find the DEC adjust screw to be very hard to turn when polar aligning, I have found something that works well for me. When I was out last time I found it all but impossible to move the DEC screw when trying to lift the weight of the mount. It was so stiff that I had to have someone lift the counter weights to get the screw in and then it was even hard to move in the opposite direction. I called Larry and he said it was due to the saddle design, instead of a pivot system. I asked if there was something I could do, because polar alignment was near impossible for me. He said, "Start High and then is is easier to let it back down", which helps only a little. So, I took the mount apart and took a look at the way the screw worked.

Well, it is just a bolt with a sharp ring on the nose and it eats a half circle in the aluminum part that it pushes on when adjusting it. Plus the surface of the cast part was rough with bumps and just rough surface. I thought that I could do much better than this and decided to try. First I took a file and made the surface smooth and flat, basically surface the metal part. Then I used a small block with sand paper to semi-polish the surface. I could not completely remove the half circle cut in to the surface, but did remove most of it.

Land Milled

Milled Surface

The I took a piece of Teflon that was 3/16" thick, 1/4" might have even been better, but this is what I had, and I cut a 7/8" circular puck from it with a hole saw with the centering drill bit removed. So this gave me a coin like puck to use. Then I used a 7/16" drill bit to make a partial hole, in other word a depression that was about 1/8" deep, leaving 1/16" of Teflon. This fits the end of the 1/2" bolt end that has a taper to it. I thing removed the sharp edge from the nose of the bolt, just enough to smooth it so that it was more of a ball shape and no sharp edges. Now the end fit nicely into the depression in the Teflon Puck. Next I applied Lithium grease to the depression in the Teflon and on the rear surface of the Teflon Puck where it would contact the metal surface when the bolt was tightened. The Teflon stays on the bolt while you lower the upper part of the mount into place on the saddle. Then when you let it slide until it contacts the Teflon puck, the grease on the back side sticks to the smooth surface, but the bolt will now come away from the puck, should you tilt the mount unintentionally, so the puck stays in place and does not fall into the base almost like a glue.

Bold Puck
Bold and Puck

Puck installed
Puck Installed on bolt

 I also applied wax to the threads of the bolt, so that it was lubricated but would not attract dirt. Reassemble everything and now the DEC moves much easier and smoother in either direction. In fact, if you have the two locking levers partially tightened, it still can be moved against this friction. But if you lock the lever tightly then it can not be moved. This really seems to work well, The puck can slide if it needs to when the DEC angle is changed because the smooth surface and the grease makes it move nicely. Plus the depression in the Teflon keeps the end of the bolt in place in the Teflon puck, so that it does not jump off of the puck. I checked to see that the DEC can me manually pulled away from the bolt and that the Teflon stays in place and it does and the bolt just goes right back into the depression. This mod does not require any special tools and other than smoothing the one metal surface, it does not do any permanent changes. The smoothed metal surface look great and certainly is not a detrimental mod.

Pluck Land
This is where the puck lands on the milled surface.