Isolation Routing PCBs

[cropwell]

"Entropy Driven Storage Area". Sounds like my brain. Though there are occasions when "It is a shitheap, mainly on the floor" fits as well!

I've been successfully using the toner transfer method for PCBs for some years. I prefer surface mount components myself (easier than drilling all those exactly spaced holes) where the spacing between tracks can be only 0.6mm for SOIC chips. Have you any experience of cutting PCBs for SMD components? I'd be interested to see how the two methods compare.

Kit

I used to etch boards and find the chemical etching dirty and dangerous and you have the spent chemicals to dispose of. Then you have to accurately drill ! Nah! CNC for me !

[magicniner]

I used to etch boards and find the chemical etching dirty and dangerous and you have the spent chemicals to dispose of.

It was great fun though! I remember building my UVA light box (pre-internet search engines) with a home brewed electronic timer and ink jet printing circuits on transparency. All info had to come from books, magazines and parts and consumable suppliers :D

[cropwell]

It was great fun though! I remember building my UVA light box (pre-internet search engines) with a home brewed electronic timer and ink jet printing circuits on transparency. All info had to come from books, magazines and parts and consumable suppliers :D

The good old days when you could just pop to Maplins for a resistor and couldn't wait for Practical Electronics or Elektor to drop through the letterbox. Before that it was red spot and white spot transistors, just can't remember which was PNP and which NPN.

[Kitwn]

It was great fun though! I remember building my UVA light box (pre-internet search engines) with a home brewed electronic timer and ink jet printing circuits on transparency. All info had to come from books, magazines and parts and consumable suppliers :D

Eeeeee lad, I remember those days! The Maplin catalogue and sending off hand filled in order forms by post, Practical Wireless, The Radio Constructor and Veroboard. In those days I drew brain-designed PCB layouts on 0.1 inch graph paper and then transferred the holes to copper board with a pin and drew in the traces using what Maplin sold as a special PCB resist pen but was actually a bog standard permanent marker, just three times the price. I even had my own personalised call sign, G0KIT. Nostalgia's not what it used to be!

More seriously, I've recently changed from using Eagle, where I never quite mastered the libraries and creating new footprints for the PCB, to DipTrace which is a bit easier to use and does have a free-for-non-commercial-use version if you look carefully enough at the website. I've only made one board with it so far but I like it so far.

As for etching, you can use remarkably little fluid by wiping it over the board with a sponge or cloth. A bit tedious but it doesn't take that long and I don't make enough boards to worry about the time.

I'm not sure my current CNC router is precise enough for milling a decent PCB. There's only one way to find out though and it would be a good test of my design and build skills. Off down another rabbit hole!

Kit

[Clive S]

And how about the XFG1 gas filled triode valve that was used in radio control receivers and mighty midget motors.

[Kitwn]

And how about the XFG1 gas filled triode valve that was used in radio control receivers and mighty midget motors.

I never got into valves until I turned from a radio amateur to a radio professional. Then I had BY1144 water cooled triodes to play with!

[cropwell]

I'm not sure my current CNC router is precise enough for milling a decent PCB. There's only one way to find out though and it would be a good test of my design and build skills. Off down another rabbit hole!
Kit

One of my biggest problems was getting the machine bed level. It is fairly good now as one side is hoiked up with brass sheet and aluminium foil to shim it level. Before that I used to cut the outline of the board and then put the board in a board-shaped pocket with some thin double sided tape. I still mill out a pocket (in the spoil board of course!) this levels up enough to get a consistent depth of cut.

Never been into radio, and the nearest to valves I have been was when I built a 15W(?) amp from a kit. It had EL84's as output stage an ECC83 phase splitter and I think ECC83's for preamp, but that was nearly 60 years ago and I haven't touched a valve since.

Rob-T

[Kitwn]

There is software out there that will probe the surface of your uncut PCB (obviously with the aid of a suitable probe mounted on the Z axis) and then modify the G-code to make the tool follow the measured undulations. I think this is the sort of refinement that might be needed for SMD boards , though a machined flat base and double-sided tape is more my kind of technology.

I have enough unfinished projects at the moment so a new way of making one or two circuit boards per year is going to stay firmly OFF the ToDo list for now.

Kit

[magicniner]

I used a Roland engraving spindle with a surface following nose on a sprung carrier for micrometer adjustable fixed depth engraving on uneven surfaces.
The engraving spindle was belt driven from the main spindle and gives 30000rpm from a 5000rpm main spindle speed.
I need to build a new unit for my new CNC though as I sold the high speed spindle arrangement with the old mill.

[cropwell]

More seriously, I've recently changed from using Eagle, where I never quite mastered the libraries and creating new footprints for the PCB, to DipTrace which is a bit easier to use and does have a free-for-non-commercial-use version if you look carefully enough at the website. I've only made one board with it so far but I like it so far.
Kit

I tried out Dip Trace last night after getting nowhere with KiCAD. Within an hour or so I had learned enough to create a schematic


and this morning create the Gerber and drill files to manipulate with CopperCAM to give me the Gcode to make the board.

All I need now is the machine back together to cut the board.

Cheers,

Rob-T