Dave, I think the finding a suitable mill bit might be a problem at this size??

Why not photo etch? Print out layout on a transperent and get some photo sensitive pcb. AFAIK you can use sunlight for the exposure.

Michael

Dave: Milling PWB's is done quite often for prototyping. There are several several machines built for that purpose and associated softwre is available to do large area copper removal to make "conventional" looking boards. Very small eyelets are normally used for layer interconnects for double sided boards. All of this is expensive however. I have used these machines some and they work well.

I have milled PWB's with a CNC milling machine for years doing the same type of layout style that you are doing where a minimum amount of copper is removed. I normally use a conical point engraving type cutter with a flattened tip to give about 0.005 wide removal line width. These cost aobut $10 or so if you buy them or take about 5 minutes to make from a "used up" 1/8 shank carbide end mill using a diamond wheel. They like to turn at 20K RPM or more but will work at 3500 in a pinch. You do need to use carbide as glass board really eats up HHS rapidly.

Thanks for that.
Maybe a dremel mounted verticaly with a suitable tip might even work for small pcb's.

Picture of pcb with components

I am sure I can mill pcbs with my Proxxon CNC conversion. Another possibility would be to build a small hand cranked mill. A few micrometer slides off ebay and a dremel

Graham

Dave,

I use a system called Press n Peel, it works by printing the pattern you want at 1:1 scale onto a special release film which you then iron onto the copper side of your PCB material. The film is peeled away to leave the printer's toner stuck to the surface of the board, the etch resist layer. You do have to etch this but the P n P system provides a clean etchant, it is completely clear and does not stain everything in sight like ferric chloride.

Press n Peel comes from USA but is available in the UK and I guess other places too I get it from MPS (Maplin).

Andy.

Thanks.

Familiar with etching process, press 'n' peel, riston etc. A lot to buy for a small pcb or two. Having said that I'm sure I would use it on other projects and when the cost is divided up!

On the other hand if you already have a mill, lathe and or dremel!
Dremel mounted over lathe, pcb fixed to slide.

Dave

.

Thats a nice looking reciever! about how much does it wiegh?

Haven't weighed it yet, but it is small and light.
The Rx I guess is about 1 gram at most.
With wires and sensor about 1.5 gram tops.

Have powered up smd IR Rx without motor attached, it works.
Must say I'm impressed with this little Rx.

Dave

Have now weighed IR Rx on 0.1 gram resolution scales, as pictured below with wires and light weight batt connecter (about 0.4 gram) and sensor weighs just 1.2 grams.

Being so light I have made a slightly larger pcb to give more room for soldering wires direct. Board will use some smaller components (pic and 1uF caps) So weight increase will be little or none.

Dave

1.2 grams

just use some thinner wire and you´ll be below 1 g

looks great!

How did you conect the TX board to your TX?
sounds promising if you can use your regular TX to IR stuff

/Philip

Phillip

Yes the wiring is a bit heavy duty. All I could lay my hands on.
Have to get something better from Graham.

The IR Tx plugs into trainer jack. Couldn't be easier.


Dave

For an quick source of wire check out dead mice cables. Not as nice as my wire but cheap.

For signal connections make your own litz wire by twisting together say 7 strands of really thin copper wire. Use a power screwdriver and anchor the other end of the bunch on a sprung hook (this helps stop snapping.

Graham

Dave,
I'm a huge convert to Graham's light weight wire. But, to save a bit of additional weight I sand off all possible excess plastic on those type of plugs. It helps. Your board looks great. Keep it up!

Gordon