Comco Microblaster Use

[Adam.morris08]

Hi all, I've been getting on well with my microblaster unit untill now.

I've had a bit of a temperature drop and more rain where I am.

I've still got about 1-1.5" of powder left in the pot but not really getting flow during use.

I get a big spurt of powder when I start the flow, but after no powder.

Is that normal? Or does it sound like damp? I didn't think damp due to the initial puff of powder as the beginning.

I'm tempted to send it off for a service anyway.

Many thanks

Adam

[Auspex]

Try baking the media, and storing it dry.

[jgcox]

You have to place moisture traps in the air lines. When you compress air whatever moisture (% humidity) is in the air gets squeezed out. When you use baking soda or dolomite they get moist and clog the media, lines and nozzle. You have to empty and bake the media to dry it out and clean the lines and nozzle. Do a search on the forum for articles about making moisture traps.

[Adam.morris08]

I have a moisture trap on it at the minute and a very good one on the way, but if it's a damp problem then surely no powder would come out?

I'm using Ali oxide at the minute

[jgcox]

Was your unit a used or refurbished? You could have a valve problem with the unit I think Comco sells a refurb kit so you can repair it yourself or they will refurb it. go onto their website and checkout their support pages. I use AL Oxide also here in Ohio and have all kinds of problems with moisture and yes you can get a small burst of powder when the pressure is first applied. Also check the grit size of your Al oxide I use a 220 grit and that reduced most of my problems.

[Adam.morris08]

Ah ok

It was a used machine I got from eBay. I think the grit I'm using is about 55 microns. It's the swam/crystal powder.

I'll see how much it will cost for a refurb. Or just the kit

[ZiggieCie]

I bake my Dolomite in the oven at 250 deg F. for 55 minutes, than keep it tightly covered. Make sure both lines are clear if you have two. A clog can happen to the best of us.

[sseth]

It sounds like one of the pinch valves. They are located on the back of the machine and can be adjusted some. They could be wearing out and the kit should help with this.

[Malcolmt]

Sounds like a moisture problem to me. I did the refurb kit a couple of years ago and it does not replace the pinch valves. The main thing the kit replaces is the bar in the vibrator block which as it wears gets rounded edges. It also replaces the lines and seals.

Sometimes the orifice at the bottom of the pot can get clogged. take it out with a nut driver and check. The size of the orifice needs to match the size of your particles. I have two different orifices that I use a .40 and a smaller .25 both obtained from Comco. It says the size on the side of the orifice. Too small an orifice and you will not get proper flow too large and you get big spurts of powder.