Making 4 oz and 10 oz copper PCB boards

[HarryN]

Hi, I am intereted in making some boards with thicker copper. A power supply design I am working on will already need 2 oz copper to work and while I am at it, I figured I might as well go overboard. It seems like miling a pcb would be less sensitive to copper thickness, so this "seems like " a good idea.

The power supply is for my flashlight hobby in case anyone is curious.

I have found copper foil in various thicknesses on the internet, but mostly they are for artwork, so about 99 % purity as opposed to the much higher purity normally found in copper wiring. Please excuse my ignorance, but I assume the foil on a PCB is quite high purity for maximum conduction - or is that a misconception?

I assume that once I find a supplier of foil and blank boards then I can epoxy it all together and be ok. Yes, I am brand new to this.

Thanks

HarryN

[admin]

Copper is nasty to mill, so I would expect that the thicker the harder it would be on the bit. You can get 2 oz clad board, I periodically see it on ebay. You can also by thin copper sheet which I would think you could laminate to fiberglass. Flashlight hobby is a new one on me, any pictures?

[HarryN]

Hi Phil, Thanks for the reply.

I have limited experience with machining, mostly some Al and Cu on hobby mills. My brother was a (manual) machinist for years and now just does it as a hobby. I am more of a wood guy - and not that great at it either.

I once tried to cut off some Cu slugs from a rod of Cu - it moves around so much it was very hard to cut. We thought about freezing it to hold it still - not sure if that works or not.

EBay can be handy, but I don't use it - my son had too many problems with them, so I just stay away. (and I mean E Bay itelf, not his customers)

I am not really sure if you want to look or not, but here are some hobby forums for flashlights http://www.candlepowerforums.com and http://www.flashlight-forums.com. You would be surprised at the number or people that get interested in something like that. I suppose it is sort of like cars and pimping them out - same thing, only cheaper and smaller. Similar anal retentive hobby to pimped out cars, and I do say that in a positive way. I actually suggest that you don't look - it is really a black hole for time and money.

I actually started wandering around cnczone because of my needs to machine flashlights, and then found your forum.

Back to PCB, I have seen for sale black markers for masking out boards by hand or touch up. I have been told that a simple black sharpie can do the same thing. I was toying with the idea of doing perhaps a reverse of the milling method -have the cnc mill mark up the board with a sharpie where you want to keep the metal and just etch it off.

I was trained as a chemical engineer, so HCl and ferric don't bother me that much.

[HarryN]

Continuing post (long winded)

I am designing a board (my second ever) as we speak, or perhaps more accurately, I have layed it out on paper and a friend is doing the eagle part. Next, I will try your software to make G Code, then I need to find someone to machine it.

I guess that is a question - is there a place on this forum to post "can anyone make this for me" kinds of questions ?

[admin]

There is now.....

[HarryN]

There is now.....

Wow - Thanks a lot - that will be really useful.

You know the last time someone did something that fast for me was when I was "father of the bride". Kind of an amazing experience.

Anyway - Thank you very much.

HarryN

[HarryN]

Hi, I might have a line on some 3/3 oz board. A friend on another forum seems to have located some commercial stock. I will post more info here as it becomes real.

Harry

[HarryN]

Hi, I managed to obtain some boards with 3oz copper on each side, and JayC managed to mill it, so that is good.

One of my needs for a project is better thermal conductivity through the board, and I am considering to buy some Bergquist TClad, which is:

http://www.bergquistcompany.com/ther...t-overview.htm

The Type (a) version I am considering is:
- standard 0.060 in thick (1.5mm) of Al core
- 0.003 thick MP (multi purpose) insulation on the Al core
- 2 oz copper foil
- 18 x 24 inch rectangles (assume you cannot use the outer 1/2 inch all around)

There is a type (b) version, everything double thickness, for about 2X the price, but I probably don't need that.

The boards are pretty good quality stuff - really pro quality for single layer circuits with thermal transfer applications.

There is a minimum though, and it is more than I need, so if anyone else is interested in going in together on this, let me know. I am not planning to really stock exta to sell, just getting enough for the intended projects, so post here if you are interested in some.

The type (a) would be about $ 90 / sheet in this qty, shipped to most places in North America and I can ship to some other places if it is not too much hassle if needed. I don't use paypal, but can work out a method for payment if you are interested and not too flakey.

Let me know by posing here I guess. Hoping to place the order in Dec 2009 or close to that.

Thanks

Harry