Material for Turret Board

[Noel Grassy]

Cool, I think I have seen brad point bits in my travels. I thought [mistakenly] that jobber's drills meant something to do with the bit's length not the bidniz end. Between a better choice of bit and clamping to a back-up board drilling should be smooth sailing. I neglected to comment on the scent this Formica gives off, ghastly & repugnant would be the description in the ad copy! It's something like burning oyster shells & human hair inna tray made of fingernails hung below yer nose. Yet somehow more acrid and less appealing.

[heisthl]

Garolite from Mcmaster - but you don't need 1/8. Use 1/16 instead it is virtually unbreakable and the thinner stuff is easier to saw, drill, punch and solder. Make sure you use the correct eyelets and turrents for the thinner stuff. A table saw with a finish blade makes the cutting easy and immediate. An eyelet staking tool will do the large turrets too but you need a smaller staking tool for the smaller single turrets. The anvil for eyelets works for the small turrets but needs to have a bigger hole for larger turrets. Most drill press anvils have a reversible piece that lets you do both sizes. Print your board layout and use double sided tape to attach it to the raw board as a drill guide. Drill the small turret holes first so you don't drill one too big by accident. When you make your first one you feel like your really manufactured something. If you want the retro look Eyelets International has bronze (not tinned) eyelets.

[statorvane]

Statorvane- I'm gonna try the formica thing. No question about it- we payin way too much for the stuff we puttin in these here amplifiers!

You can use scrap Formica leftover from a kitchen/bath project. There is usually enough of this stuff leftover from sink cutouts to make several eyelet boards. I have been lucky enough to not have to resort to home remodeling to get the Formica . One piece should be stiff enough, but I now laminate two pieces so the outside is Formica, and the wood backing is internal. I then take the laminated piece and trim off any excess with a router - leaves a nice burnished edge. I don't care for colored stuff, the white lets me make a few notes as far as component placement, etc. with a pencil.

As far as eyelets, I use the 1/8" variety from Jo Ann Fabrics - about 80 for around a buck, enough for a 'Wreck. They are located in the scrapbook supply area. To "stake" them, I insert a row of eyelets, tape them with vinyl electrical tape, flip the board and splay out the bottom of the eyelet with a #2 Phillips screwdriver bit. Then flatten the surface with a gentle tap from a hammer. Remove the tape and repeat for the next row. It helps if the board is backed by hardwood when splaying out the eyelet. I used some ash leftover from a Tele project.

So depending on your resourcefulness, you can build a custom eyelet board for the cost of the eyelets, some wood glue and a little elbow grease - about a couple of bucks.

Edit - You can see one result here, a P1 eX w/Term & 'Verb: http://s165.photobucket.com/albums/u76/ ... 20Chassis/

[titanicslim]

Stator, you are officially in my Pantheon of Heroes

To the fabric store, driver!

[gearhead]

Stator,

Where do you get your formica? I did a troll of the big guys and HD only has it in 4x8 sheets, while Lowes stopped carrying it at all.

It was fascinating to learn the origin of formica; a cheap and moldable replacement for mica as an insulator. Thanks!

[statorvane]

Where do you get your formica? I did a troll of the big guys and HD only has it in 4x8 sheets, while Lowes stopped carrying it at all.

Last time I was at Lowes I noticed they seem to be reducing their entire kitchen area. They used to have an entire aisle of range hoods - now just a few. Also noticed their Formica was 4' x 8' sheets and not much to choose from either. I think they are pushing their pre-laminated, particle board counter tops. It'd be a shame to buy a counter top to get the Formica.

Haven't been to Home Depot in a long time so I don't know what they've got. That is where I originally got the Formica. They had about a 1/2 aisle full of various colors/textures, and my favorite - white. I have found that their on-line content isn't necessarily reflective of actual store inventory.

You might also try your local/hometown home improvement stores. Also, if you know any contractors I'm sure they toss out enough from each job for a couple of eyelet boards.

BTW, there are other uses for the Formica. I used it to make the control plates for the amplifier in the link - and a little spray lacquer, decals, inkjet printer.... That 2' x 4' sheet lasted me a long time - a 4' x 8' sheet should carry me to retirement (15 years).

[benoit]

I don't know what the exact name for the laminate we use on counters in my father in law's cabinet shop, but I DO know that we throw away pieces all the time that are more than big enough to do a board with. I can find out if its formica or something else. I know its pretty stiff stuff, maybe 3/32" thick, if you glued 2 together you'd be golden. You can drill through it with minimal chipping, and it cuts fine on a table saw.

Ben

[LeftyStrat]

Likewise on the McMaster Carr G10 and Mouser turrets. I am partial to the dark blue G10. Looks cool in a black chassis.

I'm partial to the blue also. Better mojo.

I use the G10 in big sheets. It is easy to cut on a table or band saw. Looks good, and is pretty indestructible.

I also scored some pre-made turret boards from an old electronics surplus place. These are great for experimenting when layout is not as critical (NOT for a Wreck).

I have a nice little tool someone made for me that I can put in my drill press to stake the turrets. It is just a bolt with a conical nose ground on it, the other part is a bolt mounted on a board with a hole drilled about the size of a turret.

Strangely, I find drilling and staking turret boards somehow relaxing and therapeutic. Don't ask me why. Too bad you can't make lot's of money selling turret boards. I could be relaxed *and* rich.

[Trace]

What should I take into consideration when choosing a material for my turret boards? It seems to me that it would not matter much since these are mainly passive components with audio applications, maybe just a thickness issue?

What usually tends to hold up well over time is Garolite G10/FR4. While you can cut it with a jig-saw a band-saw is generally preferred. You can use a drill press to drill the holes (once you've determined your layout that is) and loading in turrets is not all that difficult. Garolite holds up well over time, it’s available in various colors, it's rugged, moisture resistant, will not warp, etc.


Good luck & I hope it helps
Trace

[drz400]

Micarta board, your local plastics company ought to supply it

See wikipedia, http://en.wikipedia.org/wiki/Micarta

FWIW one of formica's original and primary uses was electrical application.

Edit 31 Aug:
As a phenolic and cloth laminate this material in PERFECT for turret boards. Available in 1.6mm and 3.2mm thicknesses.

It may work for certain electrical motor aplications because of it's resistance to heat but compared to FR4 it is hygroscopic which can lead to some snap crackle pop 10 years later or when exposed to humid condictions. Not all micarta is made the same
You can find some that is 2% hygroscopic and some that is 1%. FR4 is the standard for PCB use and is .25% hygroscopic

[titanicslim]

It may work for certain electrical motor aplications because of it's resistance to heat but compared to FR4 it is hygroscopic which can lead to some snap crackle pop 10 years later or when exposed to humid condictions. Not all micarta is made the same
You can find some that is 2% hygroscopic and some that is 1%. FR4 is the standard for PCB use and is .25% hygroscopic

The laminates they are using now, which are seeing extensive use in all sorts of immersed conditions, seem to be holding up pretty well- and that's under hard day-to-day use, exposed. If I had any doubts about the material, I'd laminate with marine or some similar structural epoxy.

Once upon a time, I gleaned sink and grille cut-outs from cabinet shops in the Tacoma Tide Flats area. Used them for tooling when I had a small production shop. When I couldn't get them there for free, I checked at a few small lumber yards where they often had stacks of them and small ends and cutouts of laminates. You might make a few phone calls or spend a Saturday morning getting to know the "boys in the yards".

[skyboltone]

If I had any doubts about the material, I'd laminate with marine or some similar structural epoxy.

epoxy is not a good candidate when heat above 130F is present. It moves, oozes, bubbles and boils. Use weldwood resourcinol type. It comes in a powder and you mix with water. Cheap too. Just make sure to clamp it tight.

[titanicslim]

Dan

Thanks for watching my tail. That's exactly right, I didn't think of the temp. considerations. Resourcinol is also more waterproof, if you don't starve the joint and apply enough (a lot of) clamping pressure.

Another bit of news (to me, anyway) that I picked up today as I cruised the "big box stores": I was not aware that the countertop laminates are not generally available at the retail level. They are mainly selling the entire counter, with the Formica already laminated to the particle board. They told me they could special order some for me but I wanted to buy some small pieces, obviously. Have to check a few cabinet shops.

Dave

[klingo]

hello!

as i'm bored to wait for shipment..i 've tried epoxy board from junk...cleaned, sanded & cutted to size..it works like a board is supposed to in my 500v/hot amp.

computers are great...one PC power supply provide you AC plug,high voltage snubber caps, 2/5W MO resistors and enought decent wire for an amp(mostly 300v yellow black & red).

olivier

[juse]

computers are great...one PC power supply provide you AC plug,high voltage snubber caps, 2/5W MO resistors and enought decent wire for an amp(mostly 300v yellow black & red).

olivier

Thanks for the excellent idea! I just asked our IT guy here @ work for an old power supply from a junk computer & it has lots of usable stuff in it, especially the cord/adapter & wire. I can use the fan to pull the hot air out of the head cab as well. Score!