Circuit etching

[3v0]

With pulsar paper the the limiting factor is your printer just as it is with photo resist. The cost of pulsar paper + PCB is quite a bit less expensive then sensitized PCB. But you need a laminator.

Either way it takes a bit of skill.

One advantage with toner transfer is that you can use it to add graphics to the PCB.

Given you got the right stuff either method can make crappy or good looking PCBs. With both you still have to drill the holes.

 

[FreeThinker]

......
Given you got the right stuff either method can make crappy or good looking PCBs. With both you still have to drill the holes.

This is my biggest problem, drilling the holes.Always end up looking a mess holes slightly out of line etc.Have been thinking of building a cnc machine to etch and drill, anyone had any experience of this?

 

[3v0]

I have been using a CNC mill to drill the holes. I drill first and etch after. Works well. I do layout in Eagle and use the user language script pcb-gcode.ulp which generates the GCode needed for the mill.

 

[FreeThinker]

I have been using a CNC mill to drill the holes. I drill first and etch after. Works well. I do layout in Eagle and use the user language script pcb-gcode.ulp which generates the GCode needed for the mill.

Which mill have you got? what software? have tried Mach 3 on some stepper drives i've got and it works well.would like to build my machine from scratch, but not out of mdf possibly aluminium or such.Got a nice Rotozip I can use as the router drive but still looking at ideas

 

[3v0]

The machine is a MAX NC 10 at the high school. I expect you are already reading cnczone.com.

I will be playing with steppers but it is for an automation project. Expect to finish the driver board today if luck holds.

 

[FreeThinker]

cnczone, ukcnc, among others.I got my driver cards from diycnc and the steppers from ebay.Not planning a large footprint about 12 x 12 inch for pcb's and cases/panels etc.Hoping to build from aluminium mainly and leaning towards belt drive (Leadscrews and ball nuts are so expensive) hopefully timing pulleys and belts will be accurate enough.

 

[MrDEB]

I use a 1/2" drill press with a fence. If you etch first then you have a small crater to drill out.
Using the fence you drill out dip socket holes exactly in line. If you use an index mark on the fence (.1") then you get perfect spaced holes. Been doing it this way and have great results.
Use at a high rpm.
Drill bits I get from wiget supply (need to look up link) but very reasonable on HSS bits.(#65 & #68) Have even drilled out entire boards using a broken bit.
As for a laminator you can use an iron but using a laminator is best. Very consistent results. Have done .006 traces just to see if I could (two traces between ic pins)
Also found using #0000 steel wool to clean the copper laminate works very well.

 

[jbeng]

I buy my carbide drills from Electronic Goldmine.

Here's a link.

Carbide is fragile, but the drills will last a long time if you're careful.

 

[MrDEB]

Carbide is fragile for sure. Found that IF your not RIGHT ON and bit drifts into crater the bit will snap. Using the HHS the bit will flex slightly. Have used broken bits and they drill just fine.
I buy lots of stuff from Goldmine as well.
Have you tried using liquid tin after you have etched a board. Works pretty good but is kinda pricey.

 

[MrDEB]

$2.29 for 10 drill bits
Widget Supply
They carry lots of hard to find hobby stuff, nuts bolts Dremel tool stuff

 

[sanjubluerock3]

An insulating pattern applied to a printed circuit board that exposes only the areas to be soldered.

 

[FreeThinker]

I use a 1/2" drill press with a fence. If you etch first then you have a small crater to drill out.
Using the fence you drill out dip socket holes exactly in line.

Yes I've used a similar idea with some success but stil find drilling boards a real pain and I'm far too mean to get them made by a pcb house so I thought that a small cnc machine might be fun and usefull.The mechanical parts aren't rocket science but getting every thing aligned will be the pig,still with a small travel the errors will not be as bad as if I was making a 1xmetre by 1metre.Have most of the electronics to hand and an old rotozip for the spindle so I'm good to go.Will be after Christmas before I start though as I need a new Electronics Lab (read Shed Lol)

 

[aalauzier]

The video by Collin Cunningham shows him using an mini drill press with an 1/8" bit, and it seemed rather simple. Are some of the above mentioned methods harder to work with and drill out? I am trying to figure out everything that I can so I can have a solid plan going into this. Is drilling holes in a homemade pcb harder then I expect? All of these answers are very helpful to me, Thank you.

 

[MrDEB]

IF you etch then drill you end up with a crater that helps align the bit. It really is very easy. I use the thin pcb from pulsar which are somewhat transparent after etching. Very easy drilling (you can get FREE board material from PULSAR as well) with any order unless you want to just pay for shipping.
I have been able to drill out boards with 40+ holes in under 20 minutes. I have a very bright light shinning on the board as well.
attached are some pics