another Stereomour but a giant step for me

borism · 7901

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Offline borism

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on: March 13, 2014, 08:06:58 AM
Hi,

I have been reading this forum for a few months and have found it to be a great resource as well as fun to read. My kit arrived about a week ago and I have started working on it. Briefly, I have no experience working on electronics, never have used a soldering iron before and have no woodworking skills to speak of.
However, building my own amplifier was so intriguing that I just had to try. Another disclaimer is that I am well aware that I should be building the original kit but I just could not resist making some substitutions that I have seen mentioned frequently on the forum. Clearly, I am not blaming anybody else particularly when, as possible, I come back for troubleshooting help.

So my upgrades include:
goldpoint selector and stepped attenuator
cardas speaker binding posts
Mundorf coupling, parafeed caps

My main issue so far has been, unexpectedly, the finishing of the woodbase. I didn't like the streaky polyurethane finish, so I ended up sanding it down again and starting over.
(http://)
I hope the images download correctly. If not, I may need some help.

Boris

Boris


Offline Bartguy

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Reply #1 on: March 13, 2014, 09:09:00 AM
Boris, I built mine with a Goldpoint attenuator and switch, too. If you need help wiring them, (I did) let me know and I can show you how I did mine. They're working fine.



Offline Doc B.

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Reply #2 on: March 13, 2014, 09:16:26 AM
The one step finishes can end up very splotchy and streaky. I recommend using a separate stain and clear coat.

Dan "Doc B." Schmalle
President For Life
Bottlehead Corp.


Offline borism

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Reply #3 on: March 13, 2014, 02:39:11 PM
Hi Bartguy,
Yes, I think I know the wiring scheme but if you have some pictures or tips it would definitely help.

Doc, I did use a seal coat, then stain followed by polyurethane, but it was just my lack of experience. Now I intend to use shellack spray to see if I can get a smooth finish.

One more photo where things are:



Boris


Offline borism

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Reply #4 on: March 13, 2014, 02:44:42 PM
Sorry, let me try again

Boris


Offline mcandmar

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Reply #5 on: March 13, 2014, 04:01:33 PM
Doc, I did use a seal coat, then stain followed by polyurethane, but it was just my lack of experience. Now I intend to use shellack spray to see if I can get a smooth finish.

The key to poly is multiple thin coats, and sand the finish flat between each coat.  The more layers you add the flatter and smoother the finish will become.  I used four coats i mine, using finer grade sandpaper between each layer.

M.McCandless


Offline Kris

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Reply #6 on: March 13, 2014, 04:18:54 PM
I used wipe-on-poly for wood base. Can't go wrong with this stuff.



Offline JamieMcC

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Reply #7 on: March 13, 2014, 09:35:56 PM
Incrementally adding a little oil based varnish to some wipe on Danish oil or Tung oil gives similar results.

Shoot for the moon if you miss you will still be amongst the stars!


Offline borism

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Reply #8 on: March 14, 2014, 04:35:32 AM
Thanks for the tips regarding the wood finishing. I was considering a wipe on poly but ended up using the brush. My poor sanding between coats resulted in the corners being stripped of the stain. That's when I ended up sanding it all down to the wood. Has anyone tried a spray on Shellack? Or, maybe going back to some wipe-on finish is safer?

My progress is somewhat slow, in part due to time limitations. Last night I progressed to the first input wire. You'll note that I installed the power board with the 4 resistors replaced by two Mills 270 ohm (seen on this forum for 2A3 tubes) ones. My thought being less must be better. Also, I decided to replace the input wire with a Mogami 2534 quad cable. The ohm-meter was helpful in sorting and marking the wires (there are 2 blue and 2 clear coated ones). Again, I am indebted to this forum for the idea. I only got the input #3 done yesterday.
 

Boris


Offline JamieMcC

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Reply #9 on: March 14, 2014, 05:42:21 AM
I have not tried spraying shellac however I do regularly use automotive clear coat/lacquer on wood and have found it works very well if the wood is dry and well seasoned. You can also use a brush to apply I find if I dip the brush in some thinners first then wipe or spin it out so the bristles are only a little damp from the thinners then dip in the lacquer it flows out nicely.

I did these pieces with the clear earlier in the week.

Shoot for the moon if you miss you will still be amongst the stars!


Offline Doc B.

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Reply #10 on: March 14, 2014, 05:50:55 AM
Shellac can make a nice finish, but it is actually rather tricky and tedious to do in the best possible way, which is French Polish. It also makes a good filler over which to shoot nitro lacquer as a finish coat - again a whole lot of work.

My suggestion for a relatively easy and foolproof finish is no stain or a good water based stain and then brush or spray coats of a water based clear poly finish, lightly sanding with 220 grit paper between coats.

I don't use a sealer before staining, but I use a water based aniline dye and the penetration characteristics can be different than with oil based stains.

Dan "Doc B." Schmalle
President For Life
Bottlehead Corp.


Offline Grainger49

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Reply #11 on: March 14, 2014, 06:00:26 AM
Here is my suggestion for a finish:

Start at the bare wood.  Stain to your liking.  Give it a coat of spray Shellac (I have used this often) making a few light coats, 4/0 steel wool in between coats

The shellac seals the wood keeping it from soaking up a varnish.  Then spray light coats of polyurethane for shine.
« Last Edit: March 31, 2014, 02:59:09 AM by Grainger49 »



Offline mcandmar

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Reply #12 on: March 14, 2014, 06:08:48 AM
I did these pieces with the clear earlier in the week.

Sry for going off topic, but what type of wood is the sample on the left?

M.McCandless


Offline JamieMcC

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Reply #13 on: March 14, 2014, 06:38:25 AM
Hi Mark it's Spalted Beech and can be tricky to find with consistent patternation running through it, its one of my favourites and a bit different from the norm.  You can see wha I am making here as well.

Shoot for the moon if you miss you will still be amongst the stars!


Offline borism

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Reply #14 on: March 14, 2014, 07:02:17 AM
Thanks for all the suggestions.

Jamie, the wood looks beautiful. Let me know if you do some work on request.

Grainger, since I already bought a can of spray shellack, I might as well give it a try. 

Boris

Boris