Attaching the amp to the base

Cleet Torres · 2522

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Offline Cleet Torres

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on: April 25, 2014, 09:29:30 AM
I've done some searches but I have obviously not got my terminology right as I don't get any hits.

Has anybody come up with a nice elegant way to bolt down the amp to the wooden bases on their gear?

My Foreplay II I glued down, which was ok as long as I don't want to do any more work of the amp. On my seduction I drilled holes and bolted down the amp onto L joints bolted into the base - that looks good but it was a REAL pain to get that all done. My Foreplay III I turned in screws into the top of the base with washers so that the washers would hold the amp down in the base. That works well, but it really doesn't do much for the looks.

I'm going to be building a Smash soon - in 5 weeks  if Doc is on schedule  ::)  - and want to make it look as good as it will sound. Any tips and suggestions?

Thanks
Cleet



Offline mpeg2

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Reply #1 on: April 25, 2014, 09:39:47 AM
Unless you want to have your amp on its side, why do you need to attach the amp to the wood base? Doesn't gravity do a pretty good job on its own?

Just curious.

   RIch



Offline Paul Birkeland

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Reply #2 on: April 25, 2014, 10:09:07 AM
The nicest looking method I have seen is to glue some square rod stock into each corner that sits flush with the lip on the base, then drill a small hole in each corner and drive a screw into that stock.

I would expect longer life out of acetal (Delrin) stock screwed into the wood in each corner, then drilled and tapped for a machine screw. 

You can also get a Blumenstein base.

-PB

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline Gerry E.

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Reply #3 on: April 25, 2014, 11:24:35 AM

You can also get a Blumenstein base.

-PB

+1!  That was going to be my suggestion too.

http://www.blumensteinaudio.com/amplifierbases/

Gerry



Offline Jim R.

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Reply #4 on: April 25, 2014, 12:43:36 PM
The corner stock that PB mentioned is a nice approach but generally can't be done  well in the corners with the IEC inlet and RCAs. I typically glue a piece of stock to the front and rear (or sides) and then with a long drill bit drill holes in the top plate and through the stock at the bottom and then either enlarge the holes for threaded inserts or drill them initially for tapping to the thread on the bolts. This requires longer than standard bolts and/or threaded inserts. I generally use an 8-32 bolt and threaded insert but I have one base where I just used the bolt to tap the hole in the bottom stock and it works fine..

Just to be clear -- the stock pieces are glued to the bases near the bottom edge, which also gives you more room to work with for alternate footers. Also use something like ash if you can -- it's hard, but not brittle like maple.

HTH,

Jim

Jim Rebman -- recovering audiophile

Equitech balanced power; uRendu, USB processor -> Musette DAC -> 5670 tube buffer -> Finale Audio F138 FFX -> Cain and Cain Abbys near-field).

s.e.x. 2.1 under construction.  Want list: Stereomour II

All ICs homemade (speaker and power next)


Offline Cleet Torres

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Reply #5 on: April 25, 2014, 01:49:10 PM
Hi Jim

Do you have some pics I can have a look at?

thanks
Cleet



Offline Jim R.

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Reply #6 on: April 25, 2014, 02:24:55 PM
So far i've done this with my s.e.x. 2.0 and my crack (but that has a new top plate which hasn't been drilled yet, and i plan to drill the stereomour base sometime this weekend, but I'll try to get good pics of the s.e.x. 2.0 tomorrow.bbb

Jim Rebman -- recovering audiophile

Equitech balanced power; uRendu, USB processor -> Musette DAC -> 5670 tube buffer -> Finale Audio F138 FFX -> Cain and Cain Abbys near-field).

s.e.x. 2.1 under construction.  Want list: Stereomour II

All ICs homemade (speaker and power next)


Offline Guy Boisvert

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Reply #7 on: April 27, 2014, 10:32:42 AM
All my Bottlehead plates are attached to the base as shown on the photos. I glue 2 small pieces of pine on 2 opposite sides; I drill two small holes in the plate and insert a small stainless steel screw. I leave a gap of about 1/8" between the plate and the top of the piece of pine. Screws are just snug.



Offline Cleet Torres

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Reply #8 on: April 28, 2014, 12:48:08 AM
Looks great Guy.

Yep, looks like the way to go. I like Doc's Alderwood bases - maybe I am just used to them, so Id like to keep "stock" bottlehead look.


Cleet



Offline Jim R.

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Reply #9 on: April 29, 2014, 01:25:38 PM
Cleet,

Sorry about no pics yet -- that amp is in the garage somewhere and I haven't found it yet. I'll just say that my approach is very similar to Guy's but with longer bolts and wood strips glued near the bottom edge of the amp. I think I like Guy's approach a lot better actually.

-- Jim

Jim Rebman -- recovering audiophile

Equitech balanced power; uRendu, USB processor -> Musette DAC -> 5670 tube buffer -> Finale Audio F138 FFX -> Cain and Cain Abbys near-field).

s.e.x. 2.1 under construction.  Want list: Stereomour II

All ICs homemade (speaker and power next)


Offline Cleet Torres

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Reply #10 on: April 30, 2014, 06:09:45 AM
Hi Jim

I think I have done something similar to what you describe , with the exception that I used small "L" joints at the bottom instead of wood. I tend to agree with you; it does seem to be a better idea to have the wood up top. With the wood up top the chassis actually rests against the wood rather than being under tension.

Regards
Cleet