|
Welcome Page
Qweak
|
|
Region 3 Drift Chambers
|
|
Construction
Software
DAQ
Internal
Physics
|
|
|
| Development and Construction related Topics |
Not logged in |
 |
|
|
|
Message ID: 420
Entry time: 05/23/2007 01:36:34 PM
|
|
|
Mo Tames from Atlas Fiber called us back regarding some minor questions about the drawings.
However he also wanted to know the exact diameter of the holes used to put dowel pins through.
For gluing a frame made from 4 boards we use eight 1/4" dowel pins to lock the frame. The 1/4" dowel pins will be presses fit into the reamed hole located at the frame corners where two G-10 boards will overlap.
For stacking the frames as part of the assembly we use 3/8" dowel pins for alignment. The 3/8" dowel pins
will have a slip fit. There are 12 locations on each frame, but most probably only 2 locations will be used to align
two frames at a time. Because of the up to +-5mil tolerances for the hole location it might be tough to get a dowel
pins to go through all 8 stacked frames, so it is better to have more dowel pins holes than we actually need.
So we thought Atlas Fiber would figure out to which hole diameter these dowel pin holes have to reamed ...
apparently they are shifting responsibility to us and we have to figure this out.
Last week I ordered 4x 6"12"x0.5" G-10 boards for testing various reamed hole size diameters and Kirk from the W&M Machine Shop ordered several (expensive) undersized reamers and precision dowel pins from McMaster.
On Tuesday 06-5-2007 the machine shop finished the test board. Based on this board:
1/4" dowel pin,press fit: 0.2497" hole diameter. You can push the dowel pin with some force through the reamed hole.
3/8" dowel pin, slip fit: 0.3760" hole diameter. Reflects the +-5mil max. tolerances on the long board
|
|
|
|
|
|
|