Tight Clearances on a Series II chassis for WOPL
- Thread starter WOPL Sniffer
- Start date
Glen found this clearance problem when he rebuilt his 700II.
Here is the thread: Post #5
http://forums.phxaudiotape.com/showthread.php/5834-Glen-s-700-series-II-build
Here is the thread: Post #5
http://forums.phxaudiotape.com/showthread.php/5834-Glen-s-700-series-II-build
after wading through 100 pics of scantily clad women and some guy in a tutu, I thought it was easier to ask.
Since the Clair amps have machine screws and not sheet metal screws for the top and bottom covers, the screw bosses in the chassis make it really tight to insert the backplanes. I had to remove the standoffs and thermal switches and slide the backplanes into position from left to right and after positioning them where they needed to be, I installed the thermal switches and standoffs. 1/64 of an inch narrower from the top and bottom of the board edges and it would have been perfect. Or, a can of metal stretcher for the chassis.....
Thanks Mike
Since the Clair amps have machine screws and not sheet metal screws for the top and bottom covers, the screw bosses in the chassis make it really tight to insert the backplanes. I had to remove the standoffs and thermal switches and slide the backplanes into position from left to right and after positioning them where they needed to be, I installed the thermal switches and standoffs. 1/64 of an inch narrower from the top and bottom of the board edges and it would have been perfect. Or, a can of metal stretcher for the chassis.....
Thanks Mike
Lee- So far, the 2 Ser II's that have been worked on exhibit this feature. From what I found with Przems it looked like the chassis were bent in the wrong place making them smaller in that dimension....maybe it was a Series wide mistake...
Glen First Problem
Glen First Problem
So the Back Plates were built for the B series. When I went to put them in they were to tight. After talking to Joe a bit I ventured out and cut about a 1/16 off each edge. This exposed the four layers of copper making up the board. I filed and the sanded the edge with 1000 grit emery to make sure the edge was clean and no copper would arc. I will clean one more time after all soldering is done then coat with epoxy and add Kapton tape to the frame as an insulator. I now have about 1/32 clearance each side to frame from Board. I hope this is now beat. Stater the board assembly with some of Dennis's gadgets to help with the standoff soldering.
I was able to use both of my the soldering pencil irons at once to preheat the standoff . Tip hear: keep going up the row as the board holds the heat and the job gets faster as you go.
I found it Mike, Thanks, this will keep it up on the top so if anybody runs into this.....
Perry
I was able to use both of my the soldering pencil irons at once to preheat the standoff . Tip hear: keep going up the row as the board holds the heat and the job gets faster as you go.
I found it Mike, Thanks, this will keep it up on the top so if anybody runs into this.....
Perry
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- Halfbiass...Electron Herder and Backass Woof
- Joined
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- Messages
- 75,023
- Location
- Gillette, Wyo.
- Tagline
- Halfbiass...Electron Herder and Backass Woof
- Joined
- Jan 14, 2011
- Messages
- 75,023
- Location
- Gillette, Wyo.
- Tagline
- Halfbiass...Electron Herder and Backass Woof
- Joined
- Jan 14, 2011
- Messages
- 75,023
- Location
- Gillette, Wyo.
- Tagline
- Halfbiass...Electron Herder and Backass Woof
- Joined
- Jan 14, 2011
- Messages
- 75,023
- Location
- Gillette, Wyo.
- Tagline
- Halfbiass...Electron Herder and Backass Woof
- Joined
- Jan 14, 2011
- Messages
- 75,023
- Location
- Gillette, Wyo.
- Tagline
- Halfbiass...Electron Herder and Backass Woof
- Joined
- Jan 14, 2011
- Messages
- 75,023
- Location
- Gillette, Wyo.
- Tagline
- Halfbiass...Electron Herder and Backass Woof
Yeah, Joe Lists them as Pem's or Standoffs same-o same-o I've seen them called Swage nuts, Clinch Nuts too. I think PEM is a generic term.
16. Securely solder the PEM standoffs to the BACKSIDE of the Backplane board (not the silkscreened side). Due to the mass of copper on the Backplane board and the mass of the PEM standoffs, it will take a professional grade temperature controlled soldering station to
maintain the temperatures needed for this soldering operation. Use a 700 degree F setting.........
16. Securely solder the PEM standoffs to the BACKSIDE of the Backplane board (not the silkscreened side). Due to the mass of copper on the Backplane board and the mass of the PEM standoffs, it will take a professional grade temperature controlled soldering station to
maintain the temperatures needed for this soldering operation. Use a 700 degree F setting.........
It is a known quality issue with the S2 chassis Perry. They made them all on Friday afternoon after lunch. The RevB Backplanes were made smaller in size as a result of this. Glen's experience was with the RevA boards.
The White Oak Chassis is the best solution, a real high quality, precision made chassis with designed in room for this with machine screws for the covers (and an IEC AC inlet).
The White Oak Chassis is the best solution, a real high quality, precision made chassis with designed in room for this with machine screws for the covers (and an IEC AC inlet).