Dangerous Prototypes Open Source Hardware

Re: A stencil8 PCB tooling block for doing solder paste sten

Reply #30 – January 30, 2013, 10:46:02 am

[quote author="ian"]I got a digitally set dispenser with lots of settings all the bits and bobs and tips (not a compressor, which I have to get) for 320rmb, about 50 bucks US. I saw some starting at $25 though, this was the most expensive one I could find. I don't have a pic, but it is scheduled for delivery Friday.[/quote]

So, they're a bit more expensive on aliexpress etc - about $100, but still not outrageous.

What did you get for an air compressor? All the options seem to be either 12v automotive ones, or huge expensive 20+ litre ones.

Re: A stencil8 PCB tooling block for doing solder paste sten

Reply #31 – January 30, 2013, 11:02:20 am

You don't want an automotive tyre one - they run continously and are horribly noisy.  You need one with a pressure tank, and generally they are a few hundred dollars for anything decent, up into the thousands.  Not sure if the hobby size ones sold at model stores have enough pressure/capacity for dispensing, but they typically are sold at a premium price.  The cheap compressors for home garage use are bulky and also very noisy when running, but once pressurised you can just turn it off and use the stored pressure to complete a dispensing job.  Belt drive are quieter than direct drive, but again more expensive.  For my work, I went with an aluminium tank model that is lighweight and also rated to be pretty quiet - but pretty expensive for hobby use.

Re: A stencil8 PCB tooling block for doing solder paste sten

Reply #32 – January 30, 2013, 11:13:25 am

I'm looking at a few alternatives right now. One would appear to be air compressors designed for use with airbrushes. They're small, cheap, have a tank, and operate at up to 70PSI.

Another alternative is Scuba or paintball gun air tanks - though then the issue is getting them refilled.

Re: A stencil8 PCB tooling block for doing solder paste sten

Reply #33 – January 30, 2013, 11:30:06 am

Yeah, the airbrush ones was what I was thinking of as "hobby size".  70psi should be OK, I think I generally have mine set around 60psi.  But the small tank means it will have to run more often, and when I looked at them I decided they don't look very solid.  In Australia they sell fo nearly $400 though at a hobby store, but maybe available cheaper online.  My 20L aluminium tank "light industrial" unit was a bit under $500.  You can get cheaper 12L ones for under $200.  Noise is the main issue with cheap ones, but of course you also need the space.

Re: A stencil8 PCB tooling block for doing solder paste sten

Reply #34 – January 30, 2013, 01:08:13 pm

Yikes. Just got back from looking at a few. 24L (20L?) is $150 at the brick and mortar. Googling I found the same with free delivery for $100, and a smaller 6L model with all the same pressure specs for $100 (both free delivery).

Re: A stencil8 PCB tooling block for doing solder paste sten

Reply #35 – January 30, 2013, 01:10:39 pm

And at that price they will be crap - you get what you pay for!

Re: A stencil8 PCB tooling block for doing solder paste sten

Reply #36 – January 30, 2013, 01:21:25 pm

I'm currently looking into alternatives for stored gas - such as buying a CO2 or air cylinder. A scuba tank would last forever and costs a pittance to fill, but tanks are expensive and bulky.

Re: A stencil8 PCB tooling block for doing solder paste sten

Reply #37 – January 30, 2013, 01:28:05 pm

I don't mind crap, I only plan to do one-offs with dispenser, stencils for multiples for sure.

adding - will wait until the dispenser it is delivered so I know the exact specs I can get away with.

Re: A stencil8 PCB tooling block for doing solder paste sten

Reply #38 – January 30, 2013, 01:35:29 pm

Fair enough!  :D

I actually started with a cheap/crap compressor many years ago, but upgraded last year once I was happy with the whole system, and wanted something that didn't require me to wear ear protection.  The compressor is also located on the other side of the workshop where I have the other machine tools, with a long pressure hose going to the electronics benches.

Re: A stencil8 PCB tooling block for doing solder paste sten

Reply #39 – January 30, 2013, 03:24:17 pm

In the US, the cheap, heavy, noisy variety are available at harbor freight.  I got one like this http://www.harborfreight.com/3-gallon-1 ... 95275.html for $40 a couple of years ago on sale.  It's marginal at its primary job of 80psi tire inflation.

Re: A stencil8 PCB tooling block for doing solder paste sten

Reply #40 – January 30, 2013, 03:25:25 pm

Biggest shipment released from customs! :) probably too late for delivery today, but in time for workshop video tomorrow for sure.

Re: A stencil8 PCB tooling block for doing solder paste sten

Reply #41 – January 30, 2013, 03:33:18 pm

[quote author="ian"]Yikes. Just got back from looking at a few. 24L (20L?) is $150 at the brick and mortar. Googling I found the same with free delivery for $100, and a smaller 6L model with all the same pressure specs for $100 (both free delivery).[/quote]

Also, have you checked out air compressors intended for airbrushes? I'm not sure, but I think they may do the job.

Re: A stencil8 PCB tooling block for doing solder paste sten

Reply #42 – January 30, 2013, 03:35:39 pm

yeah, gonna wait to get the dispenser so I know exactly what pressures it wants.

Re: A stencil8 PCB tooling block for doing solder paste sten

Reply #43 – February 06, 2013, 09:31:57 pm

[quote author="ian"]Will do. Was actually thinking of bringing them here and selling from our DP store because it's so low volume and Seeed is valuing their stock space pretty highly right now, but the tins are definitely for the Seeed Store.[/quote]

Do you have an store here?, I think you have mentioned an DP shop before also, but I cannot find it?, or is it future plans?

Re: A stencil8 PCB tooling block for doing solder paste sten

Reply #44 – February 07, 2013, 11:01:24 am

We have the free PCB store and occasionally put stuff for sale in there too.