Airbrush arrived, some advice needed!

[5thelement]

Well, my airbrush arrived the other day and i've got a can of air to use with it.

I picked up a bottle of white spirit in Asda tonight, for cleaning it mainly, but is it worth trying to thin some paint (revell enamel) with it and giving it a try on a plastic flower pot or something? just to see if it adheres/dries okay etc?

Failing that im gonna pick up one of the bottles of Revell "color mix" thinner, as im guessing thats designed for thinning revell paints.

Any advice would be appreciated.

Cheers

 

[tigertc]

Dont touch a model till your confident mate. See NigelD's tutorial on spraying in the Tutorials section....its invaluable

 

[5thelement]

Cheers, i'll go look for it now.

 

[rjwood_uk]

if you practive on a flower pot they are usually shiny....you want to get id of that sheen!

use a fine grade (about 1200) wet and dry paper and give it a wash afterwards.

good luck!

 

[5thelement]

Looks like i can forget about using this at all.

I just tried connecting up the can of air, and i cant seem to stop air pissing out the regulator attached to the can, i've tried everything, checked the o-rings, tightened it as much as possible, tried it looser, but still air leaks out somewhere from the regulator adaptor thing i cant pinpoint if its from the screw which turns the air on, or from where it screws onto the can.

So at best, i can get air coming out the air brush when i squeeze the trigger with a little leaking from the regulator, but when i release the trigger it all pisses out the adaptor on the can

I'll try put a strip of masking tape around the top part of the screw on the regulator to give it a tighter fit, but i doubt it'll make much difference.

Back to a brush for me

 

[wonwinglo]

Thats a common problem with the cannisters,sounds as if you have a really bad one,get in touch straight away with the supplier and ask for a replacement to be sent out,you could try some of that plumbers tape as a temporary fix until you get a better valve assembly.

 

[5thelement]

So it's a problem with the can itself? wouldn't of guessed that, it's a Humbrol 250ml can (yeah i know, small lol)

Should i contact Humbrol? if thats possible?

I just imagine if i take it back to the model shop i bought it from, they'll think im just trying it on to get a new can of gas lol probably lost the receipt aswell, didn't imagine i'd need it!

Thanks for letting me know, i'll give the tape a quick try and see if it makes any difference.

 

[rjwood_uk]

mine at first leaked from where the air hose attaches to the air regulator. just needed a good tightening...tryed that?

hope it all works out.

if not, get down the good old boot sales for a genny!!!

it will need to have an air regulator and a water trap, these can be bought seperatly but its always good to have in-built ones!

 

[5thelement]

Tightened everything as much as i really can, well, without resorting to pliers to tighten it further (got none pliers lying around though) lol

I just totally covered the top of the can in tape trying to seal it all, but there still some escaping, and the can got extremely cold pretty quick lol

I really have no idea whether its the regulator/adaptor which ive screwed on, or if its a problem with the can itself.

I guess these compressors have a lot going for them lol but if im being honest, if i cant get this to work, it'll be back to a brush for a good while as i cant really afford a compressor/better airbrush at the moment feel like throwing the bloody thing in the bin and just forgetting about it lol

 

[wonwinglo]

This is annoying,the problem sometimes lies with the coarse thread and soft alloy that they are made from,but it could also be the regulator,suggest that you take both back,I know that it is a pain.

The cheapest form of air is a tyre inner tube,you can get an adaptor for this,you fill up the tube with air,throw that outside out of the way and just have the airline inside,I used one for years,eventually finished up with a lorry inner tube ! seriously it is a cheap alternative,all the adaptor is is a step down size from the valve to the pipe you use on your airbrush,free air when you want it and no pesky freezing either.

 

[Bunkerbarge]

Can you try to post some pictures of the fitting, as close as you can get, inside and out and maybe we can see some possibilities.

The very old one I used to have had a cam arrangement on the top which opened the gas and you had to be carefull how you fitted it otherwise it would leak.

Basically as long as the gas comes out when you depress the valve and doesn't when you let go there is not much else to go wrong with the can.

The connection could have an 'O' Ring or a seal missing by the sound of it but I would like to see a picture if possible. Have a think about how it works and where you would expect there to be a seal. Maybe the thread is damaged and it isn't screwing down correctly before the seal has located.

Don't despair, these things happen and they are always repairable, sometimes it just requires a bit of "Out of the Box" thinking!!

 

[wonwinglo]

You must have read my thoughts Richard ? I have just been rummaging to try and find my very old unit to see how it works,it must have got thrown out at some clearout,I am pretty sure that there is a seal where it joins the inner thread,easy to loose these little perishers,how many times have you purchased something that has been opened in the shop and bits fall out on the counter and never get put back,especially when the items go in the window on display ? it must be very basic,sort a picture out 5th and lets see if we can get our heads together on this ?

 

[5thelement]

Thanks again

The airbrush was picked up on Ebay, so no doubt the guy will ask me to post it back first (more money) i guess i could ask him and see though, seems to sell a few of them.

I did try sealing off the bottom of the adaptor with my thumb and blowing through the hole the hose attaches to, to see if there was a leak in that but nothing escaped, couldnt get anything to get through anywhere, which makes me think it might be the can instead, but i really dont know, could be either i guess dont really want to buy another can to find out it's the same lol

The airbrush itself seems to work though, push the trigger and air came through, in the end i put some water in the jar and attached it, but i couldn't get anything to come through, i guess the reason being the pressure is too low because of the leak.

EDIT:

I'll go and grab some photos and post them up.

 

[rjwood_uk]

to find out if its the can, remove the regulator completely.

no air should come out what so ever as they have a valve that lets the air out when the screw goes down into it.

so if no air comes out (maybe hold in underwater in the bath to look for bubbles) then its not the can.

then try re-ataching the the regulator and screwing it down so the air starts comming out (make sure the air hose is attached firmly) and submerse the can and regulator under the water (make sure the air hose is out the water as air will obvioulsy come out of that!)

hey presto....you should be able to see where the leek is!!!

 

[5thelement]

Okay heres some pictures

The adaptor which screws onto the can in one piece

Adaptor with the "tap" unscrewed

Inside the adaptor (part which screws onto the can) o-ring intact

The "tap" (the white stuff at the top is just a bit of masking tape i tried to use to make a better seal)

edit:

No air comes out the can when the regulator isn't attached, i'll go and try the water test, as its diffuclt to tell if its coming out from the bottom of the regulator, or where the tap screws in.

 

[5thelement]

Well, water test done, it looks like it's leaking where the hose is attached, at the hose end. It even froze the water round the screw at the end of the hose.

Pretty sure this is where its coming from anyway, it leaks even more when the other end of the hose is covered.

Just to clarify, this is where

 

[rjwood_uk]

......where mine leaked first of all. that is where all the pressure is being forces into a small hole so its got more tendancies to leek. just make sure its as tight as it can be (even use plyers if you have to) seeing as unless something goes wrong with the air hose you should never actully have to undo this connection!!!

 

[5thelement]

True, i'll get hold of a pair of pliers tomorrow morning and give it a shot. *fingers crossed*

If i still have no luck, i'll contact the guy i bought it from and tell him its not working, and see what he says.

 

[wonwinglo]

Well done 5th,nice set of pictures there,try this if you have any PTFE plumbers tape try a small piece on the thread itself,if this does not cure things remove a small portion of the plastic hose and re-seat it.

As an alternative to the tape try a bit of Bluetak smeared around the thread and general area and finger tighten it up,it only takes a tiny leak with that pressure to show as it has done here,see if that works,if not we will have to think of something else ?

 

[Bunkerbarge]

5th stick a picture of the inside of the hose fitting as well. If the contact is flat it should have a seal but if it is conical it could be damaged and be leaking through the cone.

It could also be the hose connection itself, I can't see any means of holding it to the brass nipple, such as a crimped fitting.

At least wea re narrowing it down!!