Adjusting the "Universal delay drilling tool"

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Wayco

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I have two of the new Universal delay drilling tools, and the drill bit is 1/16" longer on one than on the other. Measuring from the base of the knob, one is 2 1/8" and the other is 2 3/16". Since 1/32" is one second difference in the delay, that's a 2 second variance in these two tools. Anybody know what the correct length of the drill bit should be?

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I can see where there is a set screw in the knob, so it should be easy to adjust, I just don't know what the correct length is.
 
I know to adjust the RDDT tool you just place the tool on a flat surface and adjust the bit till it touches the surface, doenst matter wether you use the 4 second or 8 second end on the table/surface, the drill bit handle should sit flat on top the adapter ring. UDDT should be similar.

I recently had my drill bit on the RDDT come loose and it removed a small amount from the delay, not the 4 seconds I needed needless to say the rocket (my sons Crayon Bank Rocket) slammed into the ground rather hard.
 
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I know to adjust the RDDT tool you just place the tool on a flat surface and adjust the bit till it touches the surface, doenst matter wether you use the 4 second or 8 second end on the table/surface, the drill bit handle should sit flat on top the adapter ring. UDDT should be similar.

I recently had my drill bit on the RDDT come loose and it removed a small amount from the delay, not the 4 seconds I needed needless to say the rocket (my sons Crayon Bank Rocket) slammed into the ground rather hard.

I use the same method for the RDDT, but the UDDT has to fit down into the forward closure and cannot be adjusted like that. I used this method that I found on the thread that gltruett linked above:

If you have an RMS delay tool as well, or a friend with a delay tool, borrow their washer, loosen the set screw, stack both washers on the tool, and set it on the delay assembly , at the 4second side. Let the drill bit just touch the delay grain and tighten the set screw.

After I set it, I measured it with my calipers using a single washer on the knob, this gives you a flat surface to set your caliper on. My measurement was 2.086, pretty close to these:

It looks like yours needs adjusting. Mine which worked well for me goes 2.1670 tip of drill bit to outer base, 2.0845 with the washer in place which makes it easier to measure with calipers.

Thanks for the link!
 
After I set it, I measured it with my calipers using a single washer on the knob, this gives you a flat surface to set your caliper on. My measurement was 2.086, pretty close to these:

Hmmm... This smells about the length of calibrated drill bit for the RMS tool (both 18-38mm and 54mm tools). I wonder if the difference in body length of the universal and RMS tools is the depth of the charge well. If that is true, it would mean knob with drill bit is interchangeable between the two, and one could calibrate length of the drill bit for the universal tool directly by inserting it into RMS tool.

The above is just speculation. I.e. don't do that until somebody confirms it is actually true!
 
Got reply from AeroTech's support. The UDDT body is shorter than RMS DDT body. The difference in length is the depth of the ejection charge well. If you have RMS tool (or a friend with RMS tool, or borrow it from someone at the launch) you can calibrate UDDT using the RMS DDT, following exactly the same procedure:

  1. Take the knob and drill bit out of UDDT.
  2. Loosen the set screw.
  3. Put the body of RMS DDT on flat surface.
  4. Insert UDDT drill bit into RMS DDT all the way down so the tip is flush with the bottom end of the tool.
  5. Put the knob back onto top of the drill bit and push down till flush with the top end of the tool.
  6. Tighten the set screw; make sure to not move drill bit or knob when tightening it.
  7. Take the knob and drill bit out. The exposed part of the drill bit should be exactly the length of the RMS DDT body.
  8. Put it back into UDDT.
Do not use washer during calibration!

While the method of using the motor and two washers to calibrate UDDT should work too, simply using RMS DDT to calibrate UDDT is nicer and simpler. You can do it anytime, no need to have the motor and/or take it out of the sealed bag, if all you want to do is to calibrate the tool before you go to launch.
 
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