[Halld-tracking-hw] CDC Drawings

[Tim Whitlatch]

10am it is. Rm 428 ARC at JLAB.

Tim

Curtis A. Meyer wrote:
> 10:00am is good  -- Curtis
> Tim Whitlatch wrote:
>> How about 10am?
>>
>> Curtis A. Meyer wrote:
>>> Hi Tim -
>>>  
>>>       can we set up a meeting tomorrow morning at 11:00am to go
>>> over all the drawings. We have a few questions that I will type in
>>> below, and then a number of questions on what certain holes are
>>> for that we can discuss.
>>>
>>> FeedThru/Donut:
>>>
>>>    1)  The groove for the glue has been slightly modified. This 
>>> looks to
>>>          be a good design as it avoids the chance of breaking a 
>>> drill bit. We
>>>          are however worried that the sharp edge will catch on 
>>> insertion. Can
>>>          we put a champfer on the sharp edge on the grooves on the 
>>> donuts
>>>          and the inserts?
>>>
>>>     2)  The vent hole on the donuts and inserts was increased in 
>>> size to 0.035.
>>>           We originally had it smaller to aid in construction so 
>>> that it is obvious
>>>            which hole the syringe goes into. They are a too close in 
>>> size now to
>>>             be able to do that. If it was increased for a 
>>> manufacturing reason, then
>>>             perhaps we should just make both holes the same size. 
>>> Otherwise, we
>>>             should shrink the vent back down.
>>>
>>>
>>> End Plates:
>>>
>>>      1) One endplate is still labeled as 6mm carbon fiber. This 
>>> needs to be fixed.
>>>
>>>      2) There are several places where 12/24 screws are used. This 
>>> is a very odd
>>>           size and difficult to get parts for. This should be 
>>> changed to a standard
>>>           size.
>>>
>>>      3) The grooves that are used to hold the shells have widths of 
>>> 0.050 and 0.100
>>>          inches. Do you have a suggestion for what we should use in 
>>> these. Basically,
>>>          we want to discuss the size of these.
>>>
>>>      4) The upstream endplate has 1 mil tolerances on the survey 
>>> ball holes and the
>>>           support rods. The down stream has 2mil tolerances. Why the 
>>> difference?
>>>
>>>      5) The holes to attach the bearing blocks seemed to us to be 
>>> very odd sizes. Perhaps
>>>           the match a known unit, but seeing them as drawn, they 
>>> seemed  odd. One is
>>>           15-thou over a 1/4 and the other is 0.188 inch.
>>>
>>>      6) It does not appear to us that there are marks on the 
>>> endplates to indicate the
>>>           first hole in each layer. There is a call-out to the 
>>> manufacturer as to which they
>>>           are, but it is not obvious that they are marked on the 
>>> plates.
>>>
>>>      7)  There is probably a good reason for this, but we noted that 
>>> the holes for support
>>>            standoffs and gas at the outer diameter are placed at 
>>> four different radii. The
>>>            numerical values for these seem to be random numbers. The 
>>> question is can these
>>>            be at round "english" numbers.
>>>
>>>      8)   We are not sure what a number of the holes are, but the 
>>> twelve  5/16" threaded holes
>>>             at 23.15" radius confused us. What are they?
>>>
>>>   Cheers -- Curtis,
>>>
>>>   
>>
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