assembly with solder paste dispenser

[Chupa]

I saw this video of someone using a EFD 1500DV solder paste dispenser/vacuum placement machine and I am in love with this idea. I was wondering what some of the opinions are out there working with this type of thing to assemble boards.  I have an IR preheat station and a hot air rework station like he uses to flow the board after placing the parts. Ebay has a couple of these 1500DV stations for $350USD.

Currently I do my SMD assembly the old fashion way with tweezers and solder and I find it to be one of the more tedious aspects of a project and am always looking for ways to make it more painless.

What are the opinions on this type of setup? Worth the money or not?

[mikeselectricstuff]

A foot operated compressed air dispensing is definitely worth it for 1-offs where you don't want the cost or leadtime of a stencil.
A foot operated vacuum pickup tool is also very useful when tweezers are too slow.
But if you're flowing a whole board, a cheap toaster oven is a lot quicker and more consistent than a hot air gun.
See this video for more info : 

[HackedFridgeMagnet]

That's a good video, when I get the time I will try and set up this.

Would a convection toaster oven be better than the normal ones?

[Monkeh]

A foot operated compressed air dispensing is definitely worth it for 1-offs where you don't want the cost or leadtime of a stencil.
A foot operated vacuum pickup tool is also very useful when tweezers are too slow.
But if you're flowing a whole board, a cheap toaster oven is a lot quicker and more consistent than a hot air gun.
See this video for more info : 

That's given me ideas of building my own vacuum desoldering rig, too. Curse you!

[Chupa]

I'm sold on this setup now.

[johnnyfp]

So I made a solder dispensing setup by putting two air solinodes on a line, one to pressurised and one to release, then hook it up to a pic Mcu that activates on pressing a foot pedal for a defined period and then releases the pressure. All this cost me $100 or so.

For the component placement i used a dual output fish air pump with the pump valves turned upside down Then attached the hose to a pen manual smd pickup tool. I drilled a hole in the pickup tool for control, to release the component but found that if you only use the metal nib (remove the rubber foot that come with the pen) theres enough pressure to keep the component sucked until it touches the paste, and then comes off.
I was surprised how well it worked. And cost me $29 for the pump and a few dollars more for the piping.

[SeanB]

Instead of using 2 solenoid valves just get a 3/2 valve with pilot air.  The pilot air connection means it can be used from vacuum to the rated pressure  with no control problems ( common pneumatic valves use the incoming air to operate the moving slide inside, so they need a minimum pressure to operate, the pilot gives a separate air connection to run this side from a regulated air supply, the ports then can be at any pressure and still operate fast and with good flow) and you simply have a air ( or vacuum) inlet and an outlet to the work, with the other port being for the exhaust side. When you power the valve it connects the inlet to the outlet, the exhaust then being closed. On power off the inlet is closed, and the outlet port is connected to the exhaust port. The exhaust port normally has a silencer, or a combined silencer and speed control, basically a needle valve to restrict the flow.

If using any system for vacuum, it is essential to have vacuum filters in line with the pump, surprisingly these are cheap and easy to find, go buy a cheap car fuel filter with a 6mm barb fitting ( cheapest one in the shelf, no matter what car it is for, just needs the 2 barb fittings to slip the pipe over) to prevent dust and other fluff getting into the pump. After it has been in use for a year you will see a lot of stuff in it.

[johnnyfp]

http://www.dealextreme.com/p/semi-automatic-glue-dropper-dispensing-controller-52250
you'd have to use a real air compressor for this

OMG! That's cheap! I would buy one just for the parts!

[Chupa]

I do have a bunch of solenoid valves around that I could use to make my own. My concern is about a compressor. I don't really want a loud pancake compressor in here. Would one of these little airbrush compressors work? Perhaps I'd probably add a accumulation tank to it. But its max PSI is only 58.

http://www.harborfreight.com/air-tools/oilless-compressors/1-5-hp-58-psi-compressor-and-airbrush-kit-95630.html

[johnnyfp]

I run my compressor at around 58PSI t with a 50-200ms pulse depending on what pad I'm doing, so it should be ok. Just be aware the 58PSI is the Maximum for this airbrush. They state "Air delivery: 0.7 CFM @ 40 PSI"