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chato de shamrock
02-03-2015, 10:02 AM
Good morning folks

I've recently ran into a speed bump when I was taking my airbrush apart to clean. As I was about to loosen the fluid nozzle I turned the tiny wrench the opposite direction (righty tighty) and the nozzle tip just fell off. I'm under the impression I might have broken it when I tightened it the previous time I used it and put it back together after maintenance because as I turned the wrench I used absolutely no force whatsoever to try and turn the wrench. It easily turned and off came the tip of the nozzle.

This is the first airbrush I've owned and I learned that i'm tightening a small piece of metal, not some lug nuts. Anyway, what's done is done and I began searching the website of the hobby shop I bought my airbrush kit from and found no parts available. I called them and was advised to call the manufacturer, Grex, and purchase directly from them seeing as they (the hobby shop) wait until they have several orders before they place one large order with Grex. I called Grex and they told me they don't sell to the public but referred me to a couple of dealers in my area. After the call I went online to visit these dealer's websites. Some didn't even have parts on their websites. I had to call them just to get a, "we don't stock parts but can order what you need" response. Those who did carry parts in stock seemed to only have needle kits and adapters to connect Grex's air control valve or quick connect set with other brands of airbrushes. So for parts like the fluid nozzle I need I'm restricted to ordering from one of Grex's dealers and waiting. A troubling thing I found was about half the people I spoke with seemed to have a knowledge of airbrushes no grater then mine, which is why I'm here asking.

My question is, is this how it is with every airbrush company out there? Are some of the more popular brands like Iwata easier to (walk into your LHS and) get parts? Do hobby shops tend to stock parts from certain brands more then others, or is there just too much in terms of number of airbrushes being sold to stock replacement parts for any? Is this something Grex customers have to deal with or do Paasche, Badger, Iwata, etc. customers also go through this when they need to order a spring, o-ring or fluid nozzle?

Two other questions, one of the o-rings on a cup broke off. I'm not sure if that was also due to over tightening. I managed to get a replacement but the replacements look much smaller and cheaper quality. I read somewhere (maybe an amazon review) that their o-rings aren't very good and the person recommended the o-rings from another brand which happen to fit Grex's cups. Does anyone have any additional info or experience regarding this? Lastly, I had a question about reading PSI's. When I set my PSI to a specific pressure (for example Alclad suggests 15 PSI) then pull the airbrush trigger I notice the PSI reading drops by about 2, 3 PSI's (for example 13 or 12 PSI). Once air stops flowing through the airbrush the PSI's will raise back to the original setting (15 PSI). Which of these readings should I follow?

Thanks in advanced for your help folks.

02-03-2015, 11:25 AM
i'm lucky to have two branches of an official tamiya distributor near me, so airbrush parts (tamiya spraywork basic) is of no problem for me (which is good, since i tend to be clumsy with some AB parts and break them on a regular basis). on the off-chance that they do not have parts, they can order it but i have to wait since they sort of wait for orders to bunch up before contacting tamiya for replacements, but so far i have yet to wait longer than a week.

regarding your PSI query...i don't actually measure the one on mine. maybe the lower psi is because there's not much backpressure which increases the reading?

02-03-2015, 12:22 PM
You can Grex parts here This great company with great service. They are in Chicago USA

chato de shamrock
02-04-2015, 12:47 AM
You can Grex parts here This great company with great service. They are in Chicago USA

I found this shop while I was doing a google search. I noticed they had the nozzle I was looking for but the drawback was they're in Chicago and I'm in Southern California, where Grex is also located. I was hoping to find shops that actually stocked parts for Grex's airbrushes and can drive out and buy them, or worse case, order the parts and pick them up within 2-3 days. Unfortunately, finding a store that stocks more then just needles and adapters and I can go pick what I need up right away doesn't seem to be an option. I was wondering if that's just how it is with airbrush users or if shops tend to stock parts from other (more popular) brands.

Hemi Killer
02-04-2015, 01:32 AM
I recently just went through a month long debacle trying to get an obscure Grex part for my Tritium airbrush.

They don't sell direct, you have to order through the distributor. What I wasn't told is that they require their distributors to place a minimum order, I believe it's $250.

So I waited for my o ring to come in, which was so small I could not find it at a dozen different places around town. In fact I am still waiting to here from my hobby shop and every time I call, they don't know when it will come.

In the mean time, I contacted Grex directly and they sent the part out immediately, no charge. Not only that, but when I first emailed them to ask for help, I didn't know what was wrong with my airbrush, it was leaking paint from the trigger area. They responded right away with a detailed description of how it works and what to look for, and he basically diagnosed it through the email.

While I find the fact that they require a minimum order is frustrating, they responded right away and were extremely helpful. They even recommended a lubricant from a competing company to lube the new o ring. I would highly recommend Grex.

I have some extra .3mm fluid nozzles. I'm stupid and have damaged about 4 needles now, and they are freaking expensive. The nozzle comes with the needle kit. If you need a .3mm nozzle, I will be happy to send you one for no charge.

I am a beginner/novice with airbrushes, but I have been using the Grex for a while. I bought their hose and compressor, then added the thumb screw adjustment. This way I can set the regulator all the way up, then adjust the pressure at the handle my turning the knob. I used to obsess over what the PSI was and I could never get it right. Now I go off sound and feel, and try and always do a test. It has made a world of difference for me. You can get the thumb screw adjuster without their compressor, but I think you need their fittings and adapters. The PSI dropping is normal. You have to think, when you;re not pulling the trigger the system is closed, so the air builds up, to a certain point. When you pull the trigger, it is releasing the air, hence the pressure drop. Where the air PSI is with the trigger depressed is the pressure you are spraying at.

02-05-2015, 11:57 PM
Chato - you want to use the pressure when the trigger is pulled or depressed depending on which type of airbrush you have.
It is normal to lose 10psi for every 25 feet of air hose
hope this helps you

02-06-2015, 01:39 AM
Chato - you can pick up a cheap air gauge with a flow control knob for about $10 at a Harbor Freight store -
I have one right at the base of my airbrush where the hose connect so I have the PSI at the base of the airbrush not just at the compressor tank

02-06-2015, 01:48 AM
May I ask how you got the part of the nozzle out that were still in the air brush housing?

chato de shamrock
02-06-2015, 07:00 PM
i was able to get the broken part out with a tiny flat head screwdriver. Although i ran into the misfortune of breaking the part, i was lucky enough to have been at Walmart a few days prior and decided to buy a 64-piece screwdriver set with a bunch of tiny Phillips and flat head bits to use on my glasses, computer etc. It was only $10. i just carefully slid in a tip that was about the size of the airbrush opening and slowly turned. Came out fairly easy. YouTube has a video using a flathead and another using the tip on an exacto knife.

Hemi i appreciate your kindness to want to help. im a bit reluctant to take you up on the offer cause those nozzles are a bit pricy for the tiny piece that they are. Would you be cool if i exchange two boxes of aoshima 19s TE37's. I have a few new sets in white and bronze. i bought more then what i plan to use so they've been sitting around for at least 2years.

chato de shamrock
02-06-2015, 08:59 PM
By the way Hemi, I keep forgetting to ask, what was the lub the folks at Grex recommended you use on the O-rings?

02-06-2015, 09:10 PM
By the way Hemi, I keep forgetting to ask, what was the lub the folks at Grex recommended you use on the O-rings?

Chato - I use the O-ring lube that Iwata recommends for their airbrushes - it is available at most places that sell airbrush stuff - at Hobby Lobby here in the USA a tube will last a lifetime and it costs about $9.00 USD. It is like a light aqua color - can't miss it when you see it and it says "lubricant" on the tube.

Hope that helps you -

02-06-2015, 09:30 PM
OH! - Chato - I meant to write to you before to let you know the reason why there is a drop in PSI when you depress the trigger it is because - the PSI before you depress the trigger is the system "holding pressure", but after the trigger is depressed you lose a few PSI "working pressure" because the air moving down the "hose" tubing creates friction on the sides of the walls of the Hose and this causes a drop in pressure - works the same with fluids in tubing - pipe - hoses etc.

Just wanted to give you a "physics" type explanation of why

Like I said Harbor Freight has a nice little "flow control valve" with a small PSI gauge on it for like $10 when I bought mine and I keep that connected right at the base of the air hose "line" and then a quick connect fitting that connects the airbrush to the "hose" line. That way I can change airbrushes quickly and adjust the pressure for each airbrush and viscosity of paint/clear I am spraying.

I usually airbrush paint at 20-25 PSI - 2K Clear at about 25-30 PSI and then 15-20 PSI for really thinned paint for shading like on heat staining an exhaust.

Remember each compressor-line-airbrush system is a little different so you should experiment a little on a box lid etc and see how your system works best before you spray anything on you hard work.

Don't be afraid to ask questions on this forum - most everyone is very receptive and happy to help. This is one of the best forums I've seen for learning new modeling techniques as most everyone is open to sharing their skills with others.

Hope this helps you some

Hemi Killer
02-06-2015, 11:17 PM
By the way Hemi, I keep forgetting to ask, what was the lub the folks at Grex recommended you use on the O-rings?

I replied to your PM, but if anyone else is wondering, they recommended Iawata Super Lube. I never even knew you could lube an airbrush. Before, I couldn't get the needle to slide in all the way, the new packing screw o-ring was tight and it grabbed the needle. Now the whole thing is just smoother and tighter than when I bought it.

I bought it on Amazon. It's expensive, like $15 for a little tube, but it's enough to last a lifetime.

02-06-2015, 11:49 PM
WOW - Hemi Killer is it that much now??
I bought some a few years ago at Hobby Lobby and only paid $8.99 + tax for the small tube of the lubricant.

HobbyLinc USA used to have it but I just checked their catalog and didn't see it there - They have the airbrush cleaner, but not the lube.


It is made by "Medea"

Hemi Killer
02-07-2015, 06:03 PM
Well I bought it on Amazon Prime, so they may have inflated the price to compensate for the free shipping. I added it to some other stuff I was ordering. Honestly, I don't mind the cost, it helped me get back up and running, and I can't imagine ever running out. But it is expensive for what it is, I think between 1-2 ounces.

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