TreadBot

[dragons_fire]

so... i ordered some motors and a motor controller from robotshop.ca, and it gave me 3 shipping options... it could come on monday for $6, friday (3 days before) for $10 or thursday for $28.. i picked friday, so i would have them mto play with over the weekend.. well, guess what i just found in my mailbox (its thursday today for those of you who dont know) !!!

so im sitting here putting it all together and thinking.. i need a way to connect all these things together...
up until now, i have always used .10 headers for all my connections such as servos and sensors.. basically everything uses headers.. so my next question is:

does anyone know of any small 2pin and 3-pin connectors, that are smaller than .1 headers?? preferably with digikey part numbers if possible...

thanks again...
Danny

[skimask]

so im sitting here putting it all together and thinking.. i need a way to connect all these things together...up until now, i have always used .10 headers for all my connections such as servos and sensors.. basically everything uses headers.. so my next question is: does anyone know of any small 2pin and 3-pin connectors, that are smaller than .1 headers?? preferably with digikey part numbers if possible...

I would stick with the .1 headers for now, easy to put together, easy to tear apart if/when you make a mistake or a modification....but that's me, I'm crazy that way... As far as the smaller types go, flat flex cable maybe?
Have fun! Don't fry anything...at least anything that's not replaceable!

[dragons_fire]

SO i got my board designed now, and i used the .1 headers. i managed to fit everything on there, plus 18 I/O pins that can go to anoterh board on top. my issues that im having now, are that i dont think i can easily do thru-hole plating at home (i managed to fit everything on the board, using only 5 vias that i will need to solder a pin through), and i took a copy the design to staples for a copy, and they charged me 4 times as much because i wanted it dark, and its not good enough for me to use. now im looking into either getting my own laser printer, or trying out the inkjet transparencies. (i have about 8 injets lying around, they come free with almost everything now. within the next year or two, im sure we will see them at the bottom of cereal boxes!!!)

[mister_e]

transparencies film work great with inkjet printer. That's what i use here. Set your printer to the best resolution mode... yeah slower but better.

I tried laser printer in the past. i gave up, sometimes the toner don't do a nice and perfect job on 10-12mils traces.

Home made Thru-hole plating would be nice... but not a trivial thing. Sure there's some rivet kit available here and there... but it's a little bit expensive for what it worth. Better to outsource your PCB to some cheap PCB fabs.

Good luck!

[skimask]

transparencies film work great with inkjet printer. That's what i use here. Set your printer to the best resolution mode... yeah slower but better. I tried laser printer in the past. i gave up, sometimes the toner don't do a nice and perfect job on 10-12mils traces. Home made Thru-hole plating would be nice... but not a trivial thing. Sure there's some rivet kit available here and there... but it's a little bit expensive for what it worth. Better to outsource your PCB to some cheap PCB fabs. Good luck!

Inkjet? Really? I didn't think that worked at all! I tried the 'Press-n-Peel' method awhile back, used the good laser printer at OfficeMax, was really careful and all that. But it seemed like my problem was with the toner.
Does the ink actually dry on the transparency or do you have to be fairly careful with it (i.e. don't bend it, etc.)? How small are you able to get reliably on the traces and circles and the like?

[mister_e]

I've never had enough guts and patience to try the press and peel method. Yeah i like dealing with chemicals and black-rooms

Depending of your printer, you won't need to care about film handling. I'm a Canon printer fan. I use a IP4200. I print the film, wait 20-30 second (just for safety sake) then do the exposure job.

The ink stick on those film really well, you can bend them as you wish. no real problem. Just make sure you select the right film model for the right printer brand and you're in business.

I'd compare few film brands to see if there's any difference between them. Not really. I use those from staples.

PCBs brand make a difference. Here we can have those from C.I.F (circuit imprimé francais) or MGChemicals. By far, i prefer MGChemicals. Hassle free, work all the time.

[dragons_fire]

i tried a transparency on my injet on the last board i did, it worked amazingly well, nice and dark, with nice edges and all... my printer doesnt have rollers after the printing head, so i dont have to worry about it smudging, i just have to let it dry for 10 minutes after..
unfortunately, with the last board, my overhead got scratched and the board came out bad...

i think what i may try, is getting a laser printer, adn try ironing the toner onto regular (not-presensitized) boards. that way, i can use cheaper boards, and skip some of the chemicals..

[mister_e]

this method may have it's advantage for sure. My biggest concern, and also why it doesn't turn me on, is the precision of your layout alignment when doing a double sided PCB. With transparencies film it's just soooo simple to do.

You place your 2 films on a white sheet (or lightened table if you have any) align them perfectly, stick them together with tape on 3 edge (create a kind of pouch) and VOILA!

Place your film on your exposure gizmo, place your PCB the way you want without having to care about alignment, start neons, few minutes later it's done... on both side!

But yeah... you have to deal with exposure time, chemicals etc... but it's working really well. I did many successful prototype PCB using fine pitch SMD components, i can't confirm if the toner method would work as this well. But as long as it's working for you... life is good

If you scratch your film, or you use a fine tip ink pencil.. or simply print it again. Make sure you inspect them carefully first.

If you mess the toner transfer, what happen? is this easy to remove? What is the aprox cost of a toner-transfer sheet?

Films can be reuse again and again.

[skimask]

Place your film on your exposure gizmo, place your PCB the way you want without having to care about alignment, start neons, few minutes later it's done... on both side!

But yeah... you have to deal with exposure time, chemicals etc... but it's working really well. I did many successful prototype PCB using fine pitch SMD components, i can't confirm if the toner method would work as this well. But as long as it's working for you... life is good

If you mess the toner transfer, what happen? is this easy to remove? What is the aprox cost of a toner-transfer sheet?

Films can be reuse again and again.

I didn't realize you were using the pre-sensitized boards. I tried that too... used a couple of 15w flourescent bulbs for exposure (not even close to the right equipment to be sure), couldn't really get the hang of it. I suppose it was because of those bulbs I used.
Toner Transfer Sheets $ - they weren't cheap, cheaper than presensitized boards, but a guy still has to buy the blank copper. If you screw up the toner, sure you can take it off with a steel wool pad, but then you have to start over again, transfer it somehow, blah blah blah.
I'd really love to get my hands on one of those Protomat S62's for the house...only $25K with the options...pocket change! NOT!