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Johnnz
3rd September 2011, 01:43 PM
Hi all,
I recently bought a second hand air compressor which came with a spray gun. I decided to make use of it on a simple MDF box I have made, but it does not appear to be working properly.

Occasionally, the spray stops completely, but disconnect the airline, remove the paint canister and reattach everything it works great - briefly.

From there on, to get any reasonable coverage of the spray I have to hold it about 100mm from the surface, from what I have read this doesnt sound right. The front most adjustment knob is very sensitive. Turned right in, it reduces the spray to a intense coin sized shape. Turned out a little it gives a fan shaped spray but turned any further the spray seems to evaporate before it hits the surface or simply doesnt come out. The other knob at the back seems to do almost nothing.

Should I be dismantling some part to soak in thinner? I have heard that certain seals inside the gun shouldn't be soaked in thinner?

Here's some pics of the gun:



http://i123.photobucket.com/albums/o306/Johnnz_photos/image002-2.jpg

http://i123.photobucket.com/albums/o306/Johnnz_photos/image001-2.jpg

China
3rd September 2011, 11:23 PM
What pressure are you runing it looks like a low pressure gun to me , if so it will not work at high pressure.If you can buy a service kit ( which I doubt) it wouldn't hurt to fit one, also what are you trying to spray with it, you may need to change the air cap and needle.
It looks like a generic gun to me I would seriously consider discarding it and buy one that is set up for what you are doing

nine fingers
4th September 2011, 10:50 AM
Johnnz, First , clean the air breather hole ,top of pot, just under the trigger.
Try spraying straight thinners , if you still have troubles , dismantle and clean. The knob at the back controls the amount of paint . NF.

Johnnz
4th September 2011, 02:48 PM
Will have a look for the breather hole. I pulled the nozzle pieces apart today and found an o ring had badly perished around the brass hexagonal screw nozzle inside the front chamber. Will replace that tomorrow and see if that helps.

Also wondering now what the hexagonal screw cap is for on the right hand side of the gun (not shown in photos)? I took it off and all that is exposed is two little tunnels one leading up and one leading down. The one that goes down allows sight of the shaft connected to the trigger. Is this an access point for lubricating the mechanism do you think?

Also wondering what the allen keyed grub screw is for at the top back, and also what the hexagon nut with the cylindrical cap is for beneath the knob at the back that NF said was for controlling the amount of paint?

Thanks for help.

Johnnz
6th September 2011, 07:20 PM
Thanks nine fingers! Once I had cleared that breather hole (buried in layers of paint) the gun worked great! Thanks again :)