FR4 cut to size and drilled (for turret boards)

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beatnik

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I am looking to get a small batch of FR4 boards cut to size and drilled to make turret boards for tube amps.

I need a neat looking job, so no hand cutting and drilling. It needs to be done with a machine, either laser cutter or a cnc router I guess.

I can eventually supply the bare material in 50cm x 10cm x 3mm sheets

Preferably EU based
 
I am looking to get a small batch of FR4 boards cut to size and drilled to make turret boards for tube amps.

I need a neat looking job, so no hand cutting and drilling. It needs to be done with a machine, either laser cutter or a cnc router I guess.

I can eventually supply the bare material in 50cm x 10cm x 3mm sheets

Preferably EU based
Do you have a dimensioned sketch of the finished product?
It's probably something I could do with my CNC and table saw.
Also a reference drawing of the turrets.
 
It is probably just as cheap to have a PCB made with no tracks, just the holes. You could even add idents to the turrets and component footprints in silk screen.

Cheers

Ian
I have considered this option, however the turret terminals I found need either 2mm or 3mm boards. The fabricator I normally use (JLCpcb) charges a premium cost for 2mm boards compared to the standard 1.6mm thickness. Can you suggest an alternative supplier for affordable 2mm or 3mm pcbs ?
Drilling can be done with a press drill and good workpiece clamping tbh. What is actual quantity ?
I need about 15 pieces of mixed sizes. Of course it can be done by hand, but it's just gonna take too much time and I don't see how it's gonna cost less than using a machine.

Do you have a dimensioned sketch of the finished product?
It's probably something I could do with my CNC and table saw.
Also a reference drawing of the turrets.
I have attached a draft pdf, this has been optimised to be made on a cnc router using a 2mm bit. Keep in mind the larger pieces would need holes added which I haven't finished drawing yet.
The drawing is made for using a 50cm x 10cm sheet that I can get from my usual parts supplier.
I have left two corners empty to screw the piece on a board.
I imagined the cnc machine would do a first pass drilling all the holes and then each individual piece is fixed using its holes and the machine would do another pass cutting out the shapes.
I am open if you have suggestions for alternative methods.

I was aware about the ready made parts from Keyelco, the single row strips would have been ok but unfortunately the sizes I need are not going to be restocked at mouser or digikey.
 

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I have considered this option, however the turret terminals I found need either 2mm or 3mm boards. The fabricator I normally use (JLCpcb) charges a premium cost for 2mm boards compared to the standard 1.6mm thickness. Can you suggest an alternative supplier for affordable 2mm or 3mm pcbs ?
You can stack 2 pcb for 3.2mm ?
 
Probably needs to glue the pieces together so a bit time consuming, not a bad idea though.

Still hoping to find someone with access to a cnc router or laser cutter...
 
I have attached a draft pdf, this has been optimised to be made on a cnc router using a 2mm bit.
The best way is to use a drill bit of the proper size for the turrets.
PDF is not the best for talking to a CNC machine. DXF is best. Several free software packages offere this possibility.
Actually, for such simple drawings, I would prefer a dimensioned sketch than a non-dimensioned pdf.
I imagined the cnc machine would do a first pass drilling all the holes and then each individual piece is fixed using its holes and the machine would do another pass cutting out the shapes.
My usual method is drilling first then cutting with a table saw. Routing contours is lengthy and dirty.
 
As turret act like rivet, if you have enough there is probably no need for gluing ?
For alignment and tight sandwich mount you can use screw/bolt/washer at 4 turret holes, which avoid plan sliding (that can be an issue for the first clamped rivet). Then put all your turrets and finish with the last 4 ?
 
I need about 15 pieces of mixed sizes. Of course it can be done by hand, but it's just gonna take too much time and I don't see how it's gonna cost less than using a machine.
Ive had good luck printing out the dimensional drawing onto a piece of paper, and overlaying it onto the turret board. Then use a drill press and drill out all the holes. Its amazing how quickly it can go when already have the holes marked. As long as the turret board isnt massive I think you could drill them out in 10-15 minutes each. By the time you factor in the setup and time of the cnc operator, not sure its really that much faster. If you have a bunch of identiical designs, you can build a "stack" of the boards and drill through them all at once.
 
Ive had good luck printing out the dimensional drawing onto a piece of paper, and overlaying it onto the turret board. Then use a drill press and drill out all the holes. Its amazing how quickly it can go when already have the holes marked. As long as the turret board isnt massive I think you could drill them out in 10-15 minutes each. By the time you factor in the setup and time of the cnc operator, not sure its really that much faster. If you have a bunch of identiical designs, you can build a "stack" of the boards and drill through them all at once.
Stacking is not recommended unless you TIGHTLY clamped together. Plus they are assorted sizes. We machine our own turret boards out of 1/4" thick Garolite, it is readily available in many colors.

If you are not machining these in an enclosed area with cutting fluid, USE A BREATHING MASK! Once this stuff gets inhaled into your lungs, it does not come out.

I will try to find some pics of ours. They do require some handling as we machine both sides of the board. But Abby or someone over there could quickly know out a bunch of different sizes out of one large sheet. Just machine the holes first. Then use the holes as your hold-down before cutting out. One-sie two-sies on the CNC need not be tedious. Just tack the entire gasoline sheet to a large spoil board on its edges. Make sure you use 3-4 fasteners per parts to hold them down to prevent lifting, rotation, or chatter.

-Tony
 
It is probably just as cheap to have a PCB made with no tracks, just the holes. You could even add idents to the turrets and component footprints in silk screen.

Cheers

Ian
PCB's are getting so inexpensive, and have quick turn arounds - we seldom run our CNC to cut PCB's unless I need a prototype that day. Having said that, our 1/4" thick turret boards for the power supply on the RCA BA tube pre builds we did were very kick-butt.
 
Hi

Just a side note as this topic pop again with new post

I recently had quality issue with 3mm (or 4 ?) coloured FR4 material, those you can buy her an there for turret board.
It appear that the supposed very high isolation/GΩ was not that high, and parallel resistance interfere with sensitive design.
I don't investigate more but I suspect the pigmented epoxy that seal the fibreglass may be the issue.

Cheers
Zam
 

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