Renegade Krome: Bubbling: Pulling my hair out!

[Mark Taylor]

Hi all

I have been airbrushing for a few years now and have pretty good knowledge of cleaning/general airbrushing etc.

Recently, I acquired a second hand Krome in a large deal with a friend. When I first saw the brush, it was spraying water without any problems, including no bubbles.

The guy who was selling it had let it get full of gunk. I took it home and cleaned it with lacquer thinner as per usual. I had a shiny new-looking airbrush as a result.

Once I started trying to spray water, I have had no end of problems. I have spent about 4 hours trying to fix it, to no avail. I am getting constant bubbling from the tip end into the paint cup. This is just with water/cleaner. Water is coming out but it is also pulsing pretty heavily. No problems with any other AB on the same compressor.

I have tried all the usual tricks, including:
- Google-Fu
- Trying out 3 sets of brand new tips (nozzles) & needles in various combinations
- Tightening/loosening needle chuck
- More, more and more cleaning in thinners
- lube
- chapstick on the threads and at the mating between tip and frame

None of the above makes a difference. Something is not right - have I just bought a broken brush or do you clever people have any sage advice to assist?

Many thanks.

 

[Robbyrockett2]

Hmm... any defects in the nozzle post where the base of the nozzle sits? have you chapsticked there? Edit: nevermind says you did in your post


Does the nozzle protrude slightly beyond the aircap when assembled?

 

[Robbyrockett2]

I just read your intro post and realized you also have a sotar.... I'm assuming it may have been acquired in the same large deal. I'm not sure of all the ins and outs of what fits what but that leads me to believe you may have a mis-matched aircap scenario going on.
@DaveG could, im sure sort that out.

 

[Mark Taylor]

Hi there, thanks for the reply.

I did not actually chapstick within the nozzle post, but rather around the nozzle itself. The chapstick on the post worked for a single blasthrough (yay) but then the bubbles returned almost immediately (boo). This tells me that the nozzle post itself is damaged (double boo); no idea how it was working when I first observed it. Perhaps I damaged it cleaning somehow? It has never happened before but there's always a first time.

Is there anything I can do except buy a whole new body? Doh

In terms of the SOTAR, I got that a few years ago - I grabbed the Krome recently as it was such a good deal - looks like it was too good to be true.

 

[DaveG]

Krome, and Sotar, well, they are basically the same... Bubbles in the cup on the Krome is always an issue with the nozzle seal against the body. It is the hold down ring that needs to be snugged up - but, you say you tried chapstick on the nozzle base and still got bubbles? Hmmm - split nozzle would also do it, but you tried new ones? The regulator cap also has to match the nozzle you are using. The fine cap needs to be use with the fine nozzle - a fine cap on a medium nozzle will cause performance problems.

 

[DaveG]

nah, I don; think the nozzle post is damaged... Badger can be a little iffy with QC, sometimes that hold down ring really needs to be tight, but with such small threads you risk damaging things. The option is to use chapstick on the base taper of the nozzle. You have to apply very carefully, as you don;t want chapstick in the nozzle, just around the base taper, so it ill seal against the mating taper on the post.

 

[Robbyrockett2]

Hi there, thanks for the reply.

I did not actually chapstick within the nozzle post, but rather around the nozzle itself. The chapstick on the post worked for a single blasthrough (yay) but then the bubbles returned almost immediately (boo). This tells me that the nozzle post itself is damaged (double boo); no idea how it was working when I first observed it. Perhaps I damaged it cleaning somehow? It has never happened before but there's always a first time.

Is there anything I can do except buy a whole new body? Doh

In terms of the SOTAR, I got that a few years ago - I grabbed the Krome recently as it was such a good deal - looks like it was too good to be true.

Id guess then that it was working because it had dried paint in the defect. If it is in fact damaged. The only way i could think to repair it without a new body is a rather complicated one that would require tinning flux in the post and then a reamer with the proper angle or a junk nozzle and some really fine lapping compound but if you are up for a project and the body is already damaged i guess it would be worth a shot.
Maybe just a new hold down ring would make it tight enough???
I think you can try the sotar one???

 

[Mark Taylor]

I have tried everything within my skillset I think. Last port of call it to actually buy a chapstick (have been using Vaseline as always before but may as well try the chapstick). The post itself looks a little shonky too- not quite a perfect circle . I think I am going to clock it up to a learning point and not spend any more cash on it (got it for around $95/£55 with extra needles etc). I may just try and sell it for less than I paid for it to someone else with the specific proviso that there is a problem. Then it can be someone else's mission!

As DaveG noted, it seems pretty similar to the 20/20 in any event.

Unless anyone else has any more ideas, I guess that's the end of my Krome testing!

 

[Mark Taylor]

I stand (quite happily) corrected. By using actual chapstick directly onto the base of the nozzle/tip, the bubbles have disappeared for the last 5 cupfuls of water.

The way to avoid getting gunk in the needle is pretty simple: the wide end of the nozzle is the perfect size for a wooden toothpick (gently slid in of course). If you 'hold' the nozzle by resting it on top of the toothpick, you can chapstick away to your heart's content without fear of filling the nozzle.

Is there anything with a little more staying power than chapstick? I can only imagine this will disappear fairly quickly.

Thank you very much for the help, both.

 

[DaveG]

I stand (quite happily) corrected. By using actual chapstick directly onto the base of the nozzle/tip, the bubbles have disappeared for the last 5 cupfuls of water.

The way to avoid getting gunk in the needle is pretty simple: the wide end of the nozzle is the perfect size for a wooden toothpick (gently slid in of course). If you 'hold' the nozzle by resting it on top of the toothpick, you can chapstick away to your heart's content without fear of filling the nozzle.

Is there anything with a little more staying power than chapstick? I can only imagine this will disappear fairly quickly.

Thank you very much for the help, both.

Actually, chapstick should last without issue... It is there simply to seal the air out, an there is not a lot going on there in terms of solvent or anything that will remove it...

 

[Mark Taylor]

Cool beans, you have just saved my Airbrush! Muchos thanks

 

[Robbyrockett2]

I stand (quite happily) corrected. By using actual chapstick directly onto the base of the nozzle/tip, the bubbles have disappeared for the last 5 cupfuls of water.

The way to avoid getting gunk in the needle is pretty simple: the wide end of the nozzle is the perfect size for a wooden toothpick (gently slid in of course). If you 'hold' the nozzle by resting it on top of the toothpick, you can chapstick away to your heart's content without fear of filling the nozzle.

Is there anything with a little more staying power than chapstick? I can only imagine this will disappear fairly quickly.

Thank you very much for the help, both.

Beeswax, If it were to become an issue.

 

[Jurien72]

Woohoo! Glad to hear you got this sorted out. Hmm I wonder if my Krome still works - its got about a million miles on it now.

 

[Champs]

Having just spent the afternoon trying to find where the air was leaking in and bubbling in the cup, I found that waxing was definitely a temporary fix. Some microsurgery on a roll of teflon tape and a fully sealed nozzle later, and I am back in business.

Is there a chance that my threads were "looser" than others? I was tearing my hair out waxing all the threads for a few moments of bubble free brushing, but a relatively thin layer of teflon has sealed up my nozzle with no extra effort required when screwing it back together.

 

[SiRoxx]

Having just spent the afternoon trying to find where the air was leaking in and bubbling in the cup, I found that waxing was definitely a temporary fix. Some microsurgery on a roll of teflon tape and a fully sealed nozzle later, and I am back in business.

Is there a chance that my threads were "looser" than others? I was tearing my hair out waxing all the threads for a few moments of bubble free brushing, but a relatively thin layer of teflon has sealed up my nozzle with no extra effort required when screwing it back together.

I would guess that it’s possible. If the nozzle has been over tightened, but not to the point of breaking, I would guess it could have deformed the thread. But that is a guess.


Sent from my iPhone using Tapatalk

 

[Champs]

I would guess that it’s possible. If the nozzle has been over tightened, but not to the point of breaking, I would guess it could have deformed the thread. But that is a guess.


Sent from my iPhone using Tapatalk

Thanks, right now I am just happy it works!
And I cant see the teflon causing any long term issues, might make it a bit harder to remove and replace if i have to keep changing the tape, but a working brush is way better than a bubbly one.

 

[crewchief227]

Thanks, right now I am just happy it works!
And I cant see the teflon causing any long term issues, might make it a bit harder to remove and replace if i have to keep changing the tape, but a working brush is way better than a bubbly one.

I'm happy it works, but where a lot of people are using their loupe to find cracked, or flared nozzles, I once made the mistake of switching the aircaps on my .18 &.23 microns. And sure the SB .18 was suddenly a paint throwing God, but loss it's fine detail, and the .23 became a clogging, bubbling nightmare. So lesson learned, no matter how insignificant that hole diameter difference was to my naked eye, it made all the difference in the world.