Why oh why is my airbrush doing this to me!!!

Hello people.

First of all, I'm sorry for all the times I complain about my airbrush, but the problems are just never ending!


I get very little time to work on my models, and when I do, I don't want to be demoralised when a perfect paintjob is ruined by airbrush problems which are happening for no reason I can think of!


The airbrush is an Iwata Eclipse CS


I have two problems I just cannot get my head around:


1) Today I was spraying Tamiya Acrylics through the airbrush, correctly thinned out with IPA. For some reason, whilst normally spraying, the airbrush would decide to spit out ( not spray ) some IPA on it's own. I don't have a clue why, it just kept on intermittently happening which was causing the paint to strip off the surface I was painting.


This is strange, because even when the cup is completely empty, and I hold down the trigger for just air, every so often this liquid will still spit out? I am not sure where it is coming from if the cup is empty?



2) Whilst also spraying the acrylics, the paint, whilst spraying normally, would all of a sudden spit or splatter out, and then spraying would continue as normal. This obviously ruins the paint job, as you suddenly have one area with alot of paint on and a slight run in comparison to the rest. This problem is similar to the first problem of some other substance randomly spitting out.




Since these problems I have done the following:


-Dismantled the airbrush
-Lubed the trigger mechanism
-Let the nozzle, needle, caps etc in airbrush cleaner before re-inserting.



Basically, I have cleaned everything I can clean as well as possible.


I then tried to spray some cleaner through to test. Was spraying normally at 23PSI at a constant release rate, and then all of a sudden it spits again, and then goes back to normal. A few seconds later it will spit again.


I notice that inserting the needle after cleaning it gets stiff about half way in and needs a slight bit of force to go in. Not sure if this is normal because the needle gets wider towards the end of it.



In the handbook it says spitting is caused by the following:
-Dried paint on needle tip - Not this I've checked
-Pigment build up in needle cap - Not this I've checked
-Air pressure too low - Not this it was fine before, still happened when I upped to 30PSI
-Pigment too thick - Maybe I will try thin the acrylics even more, as I have never had problems with Zero paints which are thinner
-Dirty airbrush - Cleaned it all
-Dried out air valve packing o-ring - I lubed the trigger mechanism


I would appreciate any help and advice here, as I will not continue to waste my time trying to build models for them to be ruined by my tools not performing how I would like them to! I just wish it performed like it did when I first used it only about a month ago!



Indy

well you said you cleaned it and that is a good start but I would say that you need to fully lube the gun, lubing the trigger mech is not lubing the needle packing, I have an Iwata gun too, and I will take some pics to show which areas need to be lubed, also what kind of lube are you useing? is it safe for use with paints? not all lubes are.

do you start spraying before your part and stop after passing over it? sometimes paint will build up on the tip of the needle, and is blown off when you first pull the trigger, this would be interpreted as spitting but would not be a problem if you pulled the trigger before you started making your pass on your model part.

also I would say to thin your paint to the concistency of milk that is about perfect for an airbrush, some heavy metalics and pearls will not spray through an airbrush no matter what you do depending on the size of the needle and fluid tip, I have Iwata custom micron C Plus and the needle and fluid tip are very small, .18mm if I remember right and I have a hard time even spraying some finer pearls but then the brush can make a line as thin as a very sharp pencil. its a give and take, I believe your airbrush should be good for just about any kind of paint though.

let me get those pics and see if I can help

Steve

Thanks mate, appreciate the quick response.

I am spraying past the object. So I start spraying before the object and move across it.

The lube I am using is the approved lube which comes with the airbrush.


I think the paint needs to be a bit thinner, but this is still no excuse for the paint to be spattering. Maybe it is because I keep the trigger down too long, and need to lift off every 10 seconds or so, but this still doesn't explain the IPA seeming to come out seperately?


The pictures will be extremely helpful, though.

Are you sure it's IPA that's spit out, or (as I suspect), moisture that is being spit out through your air source? You need to have a moisture filter on a compressor; compressed air cools in the hose, and condenses...intermittent "spitting" of water can cause big problems with a paint job, and it is quite common, especially in a humid environment. I can almost guarantee that this is your problem, and it is not the airbrush.

You can run the compressor for awhile to dry it out. But get an inline moisture trap that you splice into the hose, close to the airbrush itself.

Thanks mate. I had a big hunch that it was the compressor causing the spitting problem.

I have a water trap on the compressor, but I'll get one which also goes in between the hose and the airbrush.

ok so heres my best explanation of how to clean and lube your airbrush, I'm not too familiar with the Eclipse line but I'm sure they are similar.

first dissasembly.
http://i239.photobucket.com/albums/ff174/mugenhbtyper/IMG_5758.jpg
http://i239.photobucket.com/albums/ff174/mugenhbtyper/IMG_5761.jpg

I'm not sure if your gun has this part but it is removable and is there I'm asuming just to protect the needle itself, but I have noticed when I have sprayed with it on that paint will accumulate on the little prongs and spit from time to time, so I just remove it while I paint. and am carefull not to damage the needle tip.
http://i239.photobucket.com/albums/ff174/mugenhbtyper/IMG_5762.jpg

I clean my airbrush with laquer thinner as it removes everything, you can soak your parts too, but I would not recomend leaving them in there too long because the thinner can etch the metal and possibly damage the airbrush parts. I tear off a piece of paper towel and twist it up then dip it in the thinner and insert and twist inside the part, you'll be surprised what will come out even with regular cleaning.
http://i239.photobucket.com/albums/ff174/mugenhbtyper/IMG_5764.jpg
http://i239.photobucket.com/albums/ff174/mugenhbtyper/IMG_5766.jpg
http://i239.photobucket.com/albums/ff174/mugenhbtyper/IMG_5772.jpg
http://i239.photobucket.com/albums/ff174/mugenhbtyper/IMG_5775.jpg

now to the gun itself, there is an O ring in it this is the needle packing at the tip, this has to be cleaned well, I use a Q-tip with most of the cotton taken off the tip and the remainder twisted back tight and dip it in some thinner then clean this area out. this O ring is removable but is very hard to reinsert so I don't remove it every time to clean it but do it maybe every 3-5 times, but this O ring has to be lubed very good. A little too much is not necesarily a bad thing you can blow the exess out after reasembly before you start painting Plus the lube will not have any negative reaction with the paint if it is the proper kind.

http://i239.photobucket.com/albums/ff174/mugenhbtyper/IMG_5767.jpg
http://i239.photobucket.com/albums/ff174/mugenhbtyper/IMG_5768.jpg
http://i239.photobucket.com/albums/ff174/mugenhbtyper/IMG_5769.jpg

I also lube all threads and any moving parts, this is the lube I use it was purchased from a paint supply store for like 5 dollars and has lasted forever.
http://i239.photobucket.com/albums/ff174/mugenhbtyper/IMG_5760.jpg

Also inspect your needle and make sure the tip is not bent this will cause irratic spraying, and if you look at the needle very close in the light you will see what looks like wear on the needle itself I lube these areas aswell because they are obviosly rubbing on parts of the gun internally.

as for the moisture in the line that is a good idea to check I hadn't realy thought about it because I use a 80 gal compressor and I have a external dryer/water seperator on the tank, and have never encountered this problem, but you should pick up one of the Iwata moisture trap deals that attaches to the air inlet of the gun I've used one on my gun even before I had the dryer on the compressor and never had a problem with moisture and they are pretty cheap around 20 dollars I think.

pics off the moisture trap
http://i239.photobucket.com/albums/ff174/mugenhbtyper/IMG_5776.jpghttp://i239.photobucket.com/albums/ff174/mugenhbtyper/IMG_5777.jpg

hope this helps, if you have anymore Q's I'll try to help.
Steve

I would see what the humidity is but as its winter that typically shouldn't be the problem. This is a shot in the dark, but i had a similar problem before with a similar airbrush.

Make sure the needle is straight with a good tip, and make sure the nozzle tip isn't clogged or smushed. This is the most important thing, make sure the needle is pushed against the tip as far as it can go. (with the nozzle and tip pieces connected first) to the left, then twist the nust in the back. Sometimes the needle tends to not be seating against the nozzle tip allowing a small space that lets liquid get through (paint).

mugenhb, thanks for taking the time to post pics, this will help many people!

I'm not entirely sure how you can use dual action airbrushes like the one your have to paint whole car bodies.... my hands end up with agonising cramp. I've heard that another advantage of the pistol grip filter is that it provides a good base for the palm of your hand to clasp onto, reducing the muscle tension - would you say it is comfortable?

My first Iwata airbrush was the CR - (dual action), its a great little airbrush but I was never happy with the paint finish on car bodies, paint looked rough and uneven - my guess is that my trigger finger was constantly moving forwards and backwards a little....adjusting the flow of product... I couldn't help it, my hands would cramp.

Note: I'm talking abour triggers on your airbrush, not 'gun style triggers'.

So then I switched to SAR, single action airbrush - best paint job I've ever done and a lot less muscle ache being as I only need to push down now. The CR still has its uses for small parts obviously.

Finally, I've noticed in many images people have braided hoses, I still have my Iwata plastic hose.... will I see any benefit changing the hose to a braided material?

EDIT: Think I found my answer, to quote "Braided Hoses are much stronger than vinyl ones and highly recomended"

click the pic

http://www.harborfreight.com/cpi/photos/96400-96499/96427.gif (http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=96427)

I use these traps. I took one to hobby lobby and compared it to the Iwata trap. They are identical in every way. Right down to the mold lines on the plastic. These are VERY good filters since it lets you see if you are getting moisture in your lines. I don't see why they have to charge SO much more for the iwata part, other than profit.

I have just bought the moisture trap for the airbrush. My compressor already has one so it should work quite well once they're both on.


I'll lube up the area stated above when I take the airbrush out again later on today.


I am also using an Iwata braided hose.


Cheers for the response people, and the pictures were extremely helpful!


I will try all of what has been said and see if the problem goes away!

Using the original Tamiya thinner instead of IPA might help as well. I find the Tamiya acrylics spray much better with the dedicated thinner.....

Well, I do not disassemble AB to that extent... I use acetone as AB cleaner and from time to time unscrew needle. It works perfectly well.

I think that some moisture could built up in air line or you may left some IPA inside after cleaning.
I always spray before paint is loaded moving AB up and down - I mean AB end moves up/down. That let me spray out the rest of thinner.

And one more idea - maybe some paint blob is inside AB and occasionally is blocking paint/thinner?

Using apropriate thinners helps a lot - in this case Tamiya or Mr Hobby. I know that Tamiya's is 95% IPA + some magic ingredients (retarder) but those additives make airbrushing easier.

mugenhb, thanks for taking the time to post pics, this will help many people!

I'm not entirely sure how you can use dual action airbrushes like the one your have to paint whole car bodies.... my hands end up with agonising cramp. I've heard that another advantage of the pistol grip filter is that it provides a good base for the palm of your hand to clasp onto, reducing the muscle tension - would you say it is comfortable?

My first Iwata airbrush was the CR - (dual action), its a great little airbrush but I was never happy with the paint finish on car bodies, paint looked rough and uneven - my guess is that my trigger finger was constantly moving forwards and backwards a little....adjusting the flow of product... I couldn't help it, my hands would cramp.

Note: I'm talking abour triggers on your airbrush, not 'gun style triggers'.

So then I switched to SAR, single action airbrush - best paint job I've ever done and a lot less muscle ache being as I only need to push down now. The CR still has its uses for small parts obviously.

Finally, I've noticed in many images people have braided hoses, I still have my Iwata plastic hose.... will I see any benefit changing the hose to a braided material?

EDIT: Think I found my answer, to quote "Braided Hoses are much stronger than vinyl ones and highly recomended"

thanks, just trying to help

I would say that the pistol grip is very comfortable, I have never experieced muscle fatique while using my airbrush.

on my airbrush there is an adjustment that allows me to stop the movement of the needle where I want, so I just set the needle where I want for spraying car bodies, then spray with the needle full open, It takes the guess work out of whether your moving the needle back and forth or not.

yeah the braided hose are great, not only stronger but much more flexible, so no more tangled hose.

Steve

EDIT: also a good way to clean your brush between color changes is to fill the cup with thinner after you have got the majority of the old paint out and cover the needle/tip with an old rag or papertowl then squeeze the trigger it will cause the air to go back through the cup and blow alot of bubbles and old paint back out into the cup, then I just dump that thinner out and repeat a few times to make sure I got all the old paint out, and spray some clean thinner through for good measure.
although I'm not sure if this will work with syphon feed airbrushes.

There could be a number of things going on, but I think there my be one or two probable culprits.
First, the way you describe it, it sounds like you are getting moisture in the air, and the only way to cure that is with a moisture trap. Iwata sells a nice inline trap that doubles as a pistol grip.
Second, but less likely is that your thinner and acrylic is separating. This could be because you paints are old and are separating into their base parts. Tamiya acrylics are not real acrylics, there actually closer to lacquers (but not really). They are suspensions of fine particles in a solution, and as they get old, they separate. The other reason they could separate is because you are using cheep thinner. No offense but Tamiya thinner is not alcohol, and not all alcohols are the same, some have way more water than they say. Tamiya and water is a big bugger-up. If you are going to thin tamiya acrylics, use a) Tamiya lacquer thinner (yellow top) esp for gloss paints; b) good quality acrylic thinner; c) good quality 91% iso-butyl alcohol.

Its probably water in the line, and the moisture trap should work, and even if its not, is good for the airbrush. if your paints are more than 1yr old, go buy some new mini acrylics from Tamiya, and upgrade your thinner. The yellow top is wonderful, but not cheap. If its none of these, your painting will improve anyway, and you have not broke the bank.

No problemo, no offence. On the bottle of X-20a is written (atleast was) that it contains 95% isopropyl alcohol. However, there is no info on big 250 ml bottles

Hi, my IPA is 99% so I think that's fine.


My Acrylics are almost 4 years old, so I think that is the problem there! Along with the moisture in the air obviously.


An inline trap arrived for me today, but looks like I'll need to invest in more paints!

The IPA is not the same as Tamiya acrylic thinner. It evaporates far quicker and is much stronger stuff. Because it evaporates so quickly, the paints dry too fast and don't get time to level out. I use the IPA to strip paints (Zero base coats) so it's pretty potent stuff. The proper Tamiya thinner is by far and away the best for thinning the acrylic paints. I have a rule that I only use the same brand thinner as the paint I'm using. If it's designed for their paints you know it will work the best. IPA is fine to clean the airbrush through after use though...

If you still haven't come up with a fix maybe try this,
the same thing happened to my CS and you really need to tighten the head cap. Not just hand tight, use the wrench. Try it.

Stevenoble is right, you cannot go wrong with the manufactures thinner. The IPA is good to clean the airbrush after you are done. There is a good article in the latest FineScale Modeler about getting the best out of your airbrush.

Just for the record, my Iwata Pistol Grip filter arrived today - I have yet to try it out with product but already attached it and it instantly feels much more comfortable to hold the airbrush now - bye bye hand cramp :smokin:

Not sure if I've added this but my inline filter arrived yesterday.

Attatched it and drained quite a bit of moisture straight away, and now the spraying of the mysterious liquid has ceased!


I'm still yet to put any paint through it, so we'll have to see if the Acrylics are still jamming up at the end of the airbrush.

I had the same problem and I use an Iwata Eclipse also. Iwata's moisture filter solved the problem for me.