Hoffman Amplifiers Tube Amplifier Forum
Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: Sonny ReVerb on April 12, 2022, 04:34:44 pm
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It seems like any information on these cap cans involves replacing a current can. I've decided to use one for a new build (stupid, I know $$$). This is the metal case, negative ground type. I bought a metal mounting plate for it. Does the plate go above or below the chassis? Should the mounting hole be slightly smaller than the diameter of the can? Most of the pics I've seen of the twist-lock tabs show at least one tab soldered to the plate? Star washers for mounting the plate to ensure a good ground connection? I've used JJ cap cans with can clamps several times, but this is a different animal. Any tips or experience appreciated.
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... metal mounting plate ... twist-lock tabs show at least one tab soldered to the plate?
If its for grounding, all signal ground connections (including filter caps) should be soldered into the ground return to ensure electrical connection. How you choose to group the ground returns is a matter of preference.
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The plate usually goes under the chassis. Gives the can a neat look from topside. Look at the pics on this old Sunn for a reference...
Click on the whole chassis gutshot for a closeup.
http://www.sluckeyamps.com/sunn/sunn.htm
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That's helpful, thanks. So, it looks like the rim of the can sits on the top of the chassis for support?
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That's helpful, thanks. So, it looks like the rim of the can sits on the top of the chassis for support?
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Thanks
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Make the hole a bit smaller than the diameter of the can so the can will sit flush on top of the chassis.
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Those plates are only for the FP style cans like the FP models that AES/CE Dist sells. You wouldn't want to use these for the LCR/JJ style dual can caps.
Greg
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All went well, I guess.
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The tabs on this can aren't meant for twisting, I don't think. The original Mallory tabs were cut so they locked in when twisted. These CE tabs are solid. I just bent them over and soldered a couple to the mounting plate. Thanks for the tips.
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All went well, I guess.
Looks about perfect! Closely examine those twist tabs and you'll see two "break-away" score marks on each one. Just a slight twist (15° or so) will cause those break-aways to separate and lock the tab to the mounting plate. It's always good practice to solder one of those tabs to the mounting plate.