Perforated boards

[BLOOZE]

Hello

I need full-perforated boards with split turrets for a jtm50 black flag and for a jtm45. After that I will build for my wife (she plays bass for me) a 100watt super bass amp.
The original brown vintage material would be great but I think it s not available.

What is the difference between?

http://kurtsequipment.com/reproboards/" onclick="window.open(this.href);return false;

Or

http://smallbox.freeservers.com/catalog.html" onclick="window.open(this.href);return false;

Or should I drill and stack my own with the boards from metro

http://metroamp.com/store/product_info. ... cts_id=224" onclick="window.open(this.href);return false;

What is the right size for a jtm50 with a GZ34?
11 5/8 X 3 1/8 OR

12 1/2 X 3 1/8


Are those all made from GP03?

Any advice would be great

Thanks

[BrianH]

All of the JTM50 boards I've made for folks have been the same size as my JTM45 - 3" x 10 1/8".

Both George's blank board material and Ray's boards use GPO3, fiberglass reinforced plastic.

Ray definitely makes nice boards! Great guy and super high quality.

Mine are not made from GPO3, rather a phenolic that has no swirly pattern and are more brown-red. Phenolic is tricky stuff and varies in color and grain pattern from batch to batch. Hard to order online as what shows up at your door might look great or awful. It's also not the most fun to cut. GPO3 is easier to work with.

My 2 cents

Brian

[mwm523]

I've purchased boards from both Brian H (http://kurtsequipment.com/reproboards" onclick="window.open(this.href);return false;) and Ray D (http://smallbox.freeservers.com/catalog.html" onclick="window.open(this.href);return false;). Both are great -super high quality - but different:

Here an amp I built with Brian's board. As you can see the red is very dark, almost brown, and the board is shiny with no swirl.:




And here's one I built with Ray's board. The color is much lighter, and the board is not shiny and has swirl in it:




Like I said, both are great, you can't go wrong either way. Quality-wise, I would say they are equal. Good luck!

[BLOOZE]

Thank you for the quick answer, both boards are looking awesome.

[thousandshirts]

After that I will build for my wife (she plays bass for me) a 100watt super bass amp.

This could be a forum first - a wife who wants an amp built.

[Flames1950]

Brian's looks like phenolic in most of the pics I've seen -- it's paper or coth in a resin binder. Ray D's boards are done in red electrical-grade fiberglass.

If you're in an extremely humid environment the fiberglass is a more reliable way to go. We have had one forum member whose phenolic board managed to soak just enough humidity out of the air to start leaking current through the board. That's why George quit selling his "vintage brown" material, and my understanding was that Ray used to use phenolics but stopped for the same reason.

Understand that different types of phenolic have different amounts of humidity that they can absorb, so not all types will cause problems under all circumstances.

[BrianH]

Actually I think George stopped selling his out of lack of material, but he could clarify. My boards look identical to what George uses in his high end plexireplica.com builds. It's a canvas-based phenolic.

[Flames1950]

The "Vintage brown" was a pretty common grade of Garolite and should still be available through places like McMaster-Carr, although there is always some variation in appearance between batches if the fabric is slightly different or the resin color is slightly different. He sent me the remains of his last batch after he quit selling it; I've still got a few pieces but not a piece big enough for a JTM100 cap board. I still love the appearance of the brown and it is damn close to what many late 60's Marshalls had in them.

I've often wondered if sealing the edges and holes with shellac or lacquer would help prevent moisture absorption too, but by the time you heat a turret up a couple of times it may not matter.

[BrianH]

The "Vintage brown" was a pretty common grade of Garolite and should still be available through places like McMaster-Carr, although there is always some variation in appearance between batches if the fabric is slightly different or the resin color is slightly different.

Absolutely true in that it varies widely. Awful to cut as the dust is vicious. Instantly gives me a headache if I'm not wearing a mask. Terrible on drill bits, too. The red GPO3 is much more friendly and softer - real nice to drill and stake. No problems with moisture on my material to date - it's comes from both the UK and here in the US (actually picked it up the US stuff myself from a nearby supplier).

I would (of course) confidently build an amp with the boards I sell. The red stuff I used to get from the UK was likely very old and turned darker red from UV exposure for many years. Came from ampmaker.com and no problems reported. No moisture issues even from the rainy UK I'm sure different material absorbs moisture differently, as you said.

Maybe George is using different stuff that I, but it looks identical (I've had one of his boards) and has been quite reliable. Looks great and is quite sturdy. I like that I've been able to acquire it quite locally. You can really check out the color, texture, and how it's been stored.