Highlighting Issues

[Silenoz]

when painting with Tamiya/Gunze, when spraying for a longer time, sometimes it's necessary to thin in between, because the thinner is alcohol based (mostly) and evaporates also from the cup.

 

When there is moisture in the air supply hose, look out for one of these baby's... 

 

 

a life saver... 

[Gorby]

21 hours ago, GazB said:

Is there a particular nozzle size I should shoot for that would be good for detail work?

Mine is 0.2mm which seems to be a pretty good all-rounder - others will probably disagree, but it suits me.

[GazB]

15 minutes ago, Silenoz said:

when painting with Tamiya/Gunze, when spraying for a longer time, sometimes it's necessary to thin in between, because the thinner is alcohol based (mostly) and evaporates also from the cup.

 

When there is moisture in the air supply hose, look out for one of these baby's... 

 

 

a life saver... 

I do have one of those connected to my airhose and I will occasionally bleed it off a little just in case. I didn't consider that about the thinner, though. Although when I did get the sudden change in spray, I added another drop of thinner and then did the backwash technique to mix it.

13 minutes ago, Gorby said:

Mine is 0.2mm which seems to be a pretty good all-rounder - others will probably disagree, but it suits me.

Cool, thanks

 

https://www.amazon.co.uk/Gocheer-Precision-Airbrush-Painting-Manicure/dp/B071JBRHFH/ref=pd_sbs_21_1?_encoding=UTF8&pd_rd_i=B071JBRHFH&pd_rd_r=82c492cc-2266-11e9-bc01-5d84e75cd9b8&pd_rd_w=DF8Dh&pd_rd_wg=p6KA8&pf_rd_p=18edf98b-139a-41ee-bb40-d725dd59d1d3&pf_rd_r=PD781MZG4TM7M8GFNEHT&psc=1&refRID=PD781MZG4TM7M8GFNEHT

 

Has anyone heard of this make before? It comes with a few different needles and nozzles.

 

Gaz

[sergant-san]

I found those "no name" airbrushes to be hit and miss. Bought 3 different ones and managed to build one from all parts that works more or less OK ( use it for scenery currently and my son using it for school projects ). Also got a H&S Ultra 0.4 and Evolution Silverline 0.15 and 0.2. 

Found an interesting thing with Ultra, which can cause some issues, if your paint is not thin enough you running a risk of trapping air bubbles between nozzle and paint cup. this causing a formation of dry paint inside the nozzle which results in splattering... Easily cured by ensuring that paints are thin enough to prevent bubble formation.

 

 

[GazB]

16 hours ago, sergant-san said:

I found those "no name" airbrushes to be hit and miss. Bought 3 different ones and managed to build one from all parts that works more or less OK ( use it for scenery currently and my son using it for school projects ). Also got a H&S Ultra 0.4 and Evolution Silverline 0.15 and 0.2. 

Found an interesting thing with Ultra, which can cause some issues, if your paint is not thin enough you running a risk of trapping air bubbles between nozzle and paint cup. this causing a formation of dry paint inside the nozzle which results in splattering... Easily cured by ensuring that paints are thin enough to prevent bubble formation.

 

 

I was having a little look around different airbrushes, and came across the H&S Ultra one. I saw about the backflush issues, but that a cap was sold for it. I might shoot for one of those.

 

On a sidenote, I had a peculiar issue with my old Revell airbrush tonight. After use and cleaning, I noticed it was still spraying very slightly the water I flush out any cleaner with after so it doesn't interact with paint after. I was certain I tightened everything up. So I took it apart, made sure everything was clean and put it back together. Problem solved. It did it again later on, but also stopped after I had stripped and reassembled. It didn't seem to do it again, but I was quite confused. It was like the needle wasn't going all the way forward, so with the constant airflow on that particular brush, it was blowing out any fluid inside, but the needle wouldn't push any further forward either.

 

It seemed to stop doing it, but I had no idea what the cause was. 

 

I also tried the double action regulator on the other airbrush, and noticed that when that's attached, and I'm not depressing the trigger for air, my compressor makes a lot more of a grinding noise. Air does seem to bleed out via the moisture trap, but I was always concerned with a double action that it could cause damage to my mini compressor if the air wasn't escaping. Is that an actual issue or me being paranoid?

 

Gaz

[sergant-san]

7 hours ago, GazB said:

I was having a little look around different airbrushes, and came across the H&S Ultra one. I saw about the backflush issues, but that a cap was sold for it. I might shoot for one of those.

I prefer to mix the paint + thinner + flow improver in the separate pot rather than in the airbrush cup. It adds few seconds, but you get better consistency.

 

 

7 hours ago, GazB said:

On a sidenote, I had a peculiar issue with my old Revell airbrush tonight. After use and cleaning, I noticed it was still spraying very slightly the water I flush out any cleaner with after so it doesn't interact with paint after. I was certain I tightened everything up. So I took it apart, made sure everything was clean and put it back together. Problem solved. It did it again later on, but also stopped after I had stripped and reassembled. It didn't seem to do it again, but I was quite confused. It was like the needle wasn't going all the way forward, so with the constant airflow on that particular brush, it was blowing out any fluid inside, but the needle wouldn't push any further forward either.

 

Could be a fleck of paint stuck in the nozzle and prevented full contact between needle and the nozzle. 

 

[bmwh548]

Don't try backflushing the Ultra or you might end up "launching" the cup from the airbrush. It's not a "screw  in" cup and after a while it becomes easy to knock it off. I do the mix inside the cup using a pipette. Put a few drops of thinner, put a few drops of paint, then I pull as much as I can into the pipette and squirt it back in. Repeat the process a few times and it's ready to go. You still get a few drops in the nozzle tip that aren't perfectly mixed but I blow those away anyway when adjusting the air.

[Gorby]

1 hour ago, bmwh548 said:

Don't try backflushing the Ultra or you might end up "launching" the cup from the airbrush.

I always back-flush my Ultra to clean it and have never had that happen.

[GazB]

11 hours ago, sergant-san said:

I prefer to mix the paint + thinner + flow improver in the separate pot rather than in the airbrush cup. It adds few seconds, but you get better consistency.

 

 

 

Could be a fleck of paint stuck in the nozzle and prevented full contact between needle and the nozzle. 

 

I'm often wondering if half my problems are in the nozzle at times, despite my cleaning it, using a reamer, running cleaner/thinner through it and wicking away with a paper towel.

 

9 hours ago, bmwh548 said:

Don't try backflushing the Ultra or you might end up "launching" the cup from the airbrush. It's not a "screw  in" cup and after a while it becomes easy to knock it off. I do the mix inside the cup using a pipette. Put a few drops of thinner, put a few drops of paint, then I pull as much as I can into the pipette and squirt it back in. Repeat the process a few times and it's ready to go. You still get a few drops in the nozzle tip that aren't perfectly mixed but I blow those away anyway when adjusting the air.

Yikes Oo

 

8 hours ago, Gorby said:

I always back-flush my Ultra to clean it and have never had that happen.

I mean, Everything Airbrush was selling the cap recommended for it but, yikes.

 

Gaz

[Chrissy_J]

I had trouble with an AB that just stopped wanting to work properly (I have the same type of AB, a Chinese BD-130). In the end I changed the nozzle and needle with parts from another Chinese AB, and no more problems. 

In the short term you could try letting the nozzle soak in cellulose thinners, then taking a reamer or dental floss to it, but to be honest it might be new nozzle time. EBay has all the bits you need but you might have to wait for delivery from China, as I did for needles. It does no harm to have a few spare parts on hand so you're not stranded in mid session, in case you drop it or something.

 

Also, when it comes to cleaning or polishing an AB needle, I use a piece of green Scotchbrite on it after every stripdown.

[GazB]

15 hours ago, Chrissy_J said:

I had trouble with an AB that just stopped wanting to work properly (I have the same type of AB, a Chinese BD-130). In the end I changed the nozzle and needle with parts from another Chinese AB, and no more problems. 

In the short term you could try letting the nozzle soak in cellulose thinners, then taking a reamer or dental floss to it, but to be honest it might be new nozzle time. EBay has all the bits you need but you might have to wait for delivery from China, as I did for needles. It does no harm to have a few spare parts on hand so you're not stranded in mid session, in case you drop it or something.

 

Also, when it comes to cleaning or polishing an AB needle, I use a piece of green Scotchbrite on it after every stripdown.

Originally the nozzle that came with my first one broke, so I bought a pack of five replacements. After I got the same model airbrush when the first developed problems, I immediately switched over the nozzle. I had one replacement left and tried that the other day, but since the replacements were of dubious quality, it broke while screwing in. So I had to put the previous one back in. Its curious because I've stripped and cleaned and reassembled, but this one still doesn't seem to spray as well as the first one of this model I got (I have three ABs. A Revell one, and two of these BD-130 types). It does eventually start to spray, but certainly doesn't have the same kind of spray ability as the first BD-130 had when it worked. For example, on the first one, if I loosened the rear piece completely I could spray more easily, but this doesn't work on the new one.

 

Its very peculiar.

 

Scalemodelshop seems to sell the same model as well, just with their own name on it.

 

Gaz

[bmwh548]

Are you sure the nozzle cap is the correct one? Maybe you have a small one on a big nozzle. That wouldn't allow for enough air to flow which would make it hard to spray paint. If you have a set of small drill bits you can put one through the nozzle cap, maybe when they plated the parts too much chrome/nickel whatever got stuck on the opening. Also you can't expect to be using the same air pressure in all airbrushes. I have a BD-130, a BD-180 and an Ultra. They all require different air adjustments. I can run the Ultra at 1bar (about 15psi), but for the other ones to work I need around 1.5bar (around 20psi). And that's with the same paint.

[GazB]

3 minutes ago, bmwh548 said:

Are you sure the nozzle cap is the correct one? Maybe you have a small one on a big nozzle. That wouldn't allow for enough air to flow which would make it hard to spray paint. If you have a set of small drill bits you can put one through the nozzle cap, maybe when they plated the parts too much chrome/nickel whatever got stuck on the opening. Also you can't expect to be using the same air pressure in all airbrushes. I have a BD-130, a BD-180 and an Ultra. They all require different air adjustments. I can run the Ultra at 1bar (about 15psi), but for the other ones to work I need around 1.5bar (around 20psi). And that's with the same paint.

Well, its a 0.3mm airbrush, and the nozzles I got were 0.3mm as well. The BD-130 type AB came with a mini compressor as a set, a Floureon one. The Revell was from a different set, but works fine. On the first BD-130 type the replacement nozzles worked better than the one it came with. I'm wondering whether to swap over some parts from the first one into the second to see if it improves the performance at all. 

 

Thing with my minicompressor is, I always use it on the lowest setting, as I did with the Revell compressor. I dunno exactly what the PSI on that is, but it always worked fine.

 

Gaz

[GazB]

A curiosity, ladies and gents. In the threading for the hose connector on the AB body itself, there appears to be a small hole in the front, on both the BD-130 type and the Revell, which seems to lead into that curved piece of housing running along the ventral surface to just under the paint cup. Does that actually lead anywhere?

 

Gaz

[Chrissy_J]

That's how the air gets to the nozzle.

When you push DOWN on the lever, you open the air valve. This is like a Schrader car or bicycle tyre valve, it's spring loaded.

The air goes through the hole in the side of the air valve housing, along the channel in that ventral rib, to the nozzle cap. There's a hole under the nozzle where the air comes out, but it's very hard to see cos it's small and recessed. Depending on how far you have the needle fixed back from the nozzle, when you push the lever down you will feel some air come out. This comes out of the hole, swirls around the inside of the nozzle cap, then comes out of it.

 

Meanwhile, the paint sits above this air channel, in its cup. You can see this. When you pull the lever BACK, the needle comes out of the nozzle and allows paint to flow out of it. If you push the lever DOWN then BACK, air comes out drawing paint through the nozzle via the venturi effect, creating an spray pattern of atomised paint. The size of the pattern is determined by your air pressure, how far the needle is pulled back, and the diameter of the nozzle - the larger these factors, the bigger the spray. 

This is why paint collects on the inside of the nozzle cap; it acts as a mixing vessel before it leaves the airbrush.

 

Everyone likes pretty pictures, this is how it works:

 

I have used the component names as stated on this parts diagram. Your terminology may vary.

 

 

[Chrissy_J]

5 hours ago, GazB said:

Well, its a 0.3mm airbrush, and the nozzles I got were 0.3mm as well. The BD-130 type AB came with a mini compressor as a set, a Floureon one. The Revell was from a different set, but works fine. On the first BD-130 type the replacement nozzles worked better than the one it came with. I'm wondering whether to swap over some parts from the first one into the second to see if it improves the performance at all. 

The big, big problem with cheap airbrushes is that the quality control of the components can and does vary widely. You have to trust that every part gets along with each other. This is why quality airbrushes are more expensive - because they are precision mechanisms, individually assembled and tested.

 

It would probably do no harm to mix and match components from your ABs to try and get the best results. You will need to make sure other variables - paint type, paint thinner mixture, air pressure - are consistent, though. Write them down if necessary.

[GazB]

19 minutes ago, Chrissy_J said:

The big, big problem with cheap airbrushes is that the quality control of the components can and does vary widely. You have to trust that every part gets along with each other. This is why quality airbrushes are more expensive - because they are precision mechanisms, individually assembled and tested.

 

It would probably do no harm to mix and match components from your ABs to try and get the best results. You will need to make sure other variables - paint type, paint thinner mixture, air pressure - are consistent, though. Write them down if necessary.

Yeah, I might try it. I got the little Tamiya airbrush cleaning brush today, and put it to use on the various parts. I've cleaned things through as much as I can. Sprayed some water through with some success, although the overall flow still appears to be less than the first one. If push comes to shove, I found a UK based art shop that sells BD-130 needles and nozzles. Just hope the needle is exactly the same as the one in my clone variant.

 

Gaz

[GazB]

35 minutes ago, Chrissy_J said:

That's how the air gets to the nozzle.

When you push DOWN on the lever, you open the air valve. This is like a Schrader car or bicycle tyre valve, it's spring loaded.

The air goes through the hole in the side of the air valve housing, along the channel in that ventral rib, to the nozzle cap. There's a hole under the nozzle where the air comes out, but it's very hard to see cos it's small and recessed. Depending on how far you have the needle fixed back from the nozzle, when you push the lever down you will feel some air come out. This comes out of the hole, swirls around the inside of the nozzle cap, then comes out of it.

 

Meanwhile, the paint sits above this air channel, in its cup. You can see this. When you pull the lever BACK, the needle comes out of the nozzle and allows paint to flow out of it. If you push the lever DOWN then BACK, air comes out drawing paint through the nozzle via the venturi effect, creating an spray pattern of atomised paint. The size of the pattern is determined by your air pressure, how far the needle is pulled back, and the diameter of the nozzle - the larger these factors, the bigger the spray. 

This is why paint collects on the inside of the nozzle cap; it acts as a mixing vessel before it leaves the airbrush.

 

Everyone likes pretty pictures, this is how it works:

 

I have used the component names as stated on this parts diagram. Your terminology may vary.

 

 

Hmm, so does that air come out around the little brass tube that the nozzle screws into? Hence why if you take the full nozzle and needle cap off, nothing would spray? Is it possible paint could have gotten into that? I mean the actual airflow always feels strong, just the delivery of paint seems lacking. 

 

Gaz

[Chrissy_J]

 

3 hours ago, GazB said:

Hmm, so does that air come out around the little brass tube that the nozzle screws into?

Yup, there's a hole beneath the tube. It's really hard to see but you can feel and probe it with a piece of wire. It's about 1mm diameter.

If you can feel air coming out of it (with or without the nozzle or cap fitted) when you push the lever down, you don't have a blockage or an airfeed problem.

 

Having read the whole thread again I'm inclined to think you have a damaged nozzle, possibly caused by the bent needle tip. It'll allow water to pass through it but the paint is thicker, even when thinned, and can clog it.

Are you using a reamer shaped like a spike, with a screw-on cap? They can't clean the whole of the nozzle interior, the taper is different. You could try a piece of cotton thread or dental floss though.

 

 

[GazB]

3 minutes ago, Chrissy_J said:

 

Yup, there's a hole beneath the tube. It's really hard to see but you can feel and probe it with a piece of wire. It's about 1mm diameter.

If you can feel air coming out of it (with or without the nozzle or cap fitted) when you push the lever down, you don't have a blockage or an airfeed problem.

 

Having read the whole thread again I'm inclined to think you have a damaged nozzle, possibly caused by the bent needle tip. It'll allow water to pass through it but the paint is thicker, even when thinned, and can clog it.

Are you using a reamer shaped like a spike, with a screw-on cap? They can't clean the whole of the nozzle interior, the taper is different. You could try a piece of cotton thread or dental floss though.

 

 

I have one of the reamers, yeah. I use it to poke through the end a little, but I also remove the needle and put some thinner or cleaner in the cup and then run a piece of paper towel along the nozzle opening so it draws it through, along with some residual paint. Is there a trick to getting a piece of thread through?I

 

Gaz

[bmwh548]

Get some cotton or even some fabric from an old T-shirt or whatever. Cut very thin strips (about a millimeter in diameter) and feed one end through the nozzle (not a lot, just enough for it to get in there). Then take an old needle and push the strip all the way through so it goes through the nozzle tip (don't force it or you'll crack the nozzle, if it doesn't go just take it out and make the piece thinner). When it's in that position put a few drops of thinner and start moving the strip inside the nozzle (front and back, circle) a few times. Pull it out through the back and examine it. Repeat until the piece is clean.

If you think you have paint in the air channel grab a piece of thin steel wire and feed it through from the front until it gets to the air valve. Move it around see if it dislodges anything. With the airbrush completely apart you can use some lacquer type thinner to soak it and repeat the process. Just make sure you don't soak any rubber seals. Also keep in mind that the more you take it apart the more stress you put on the seals. They're very poor quality and tend to fall apart from too much "handling".

[Chrissy_J]

My o-ring seal (part no.4 on the diagram) disintegrated during cleaning. I now use plumbers' PTFE tape to seal the nozzle cap to the airbrush body.

You'll know if there's a leak in this area 'cos you'll get bubbles of paint coming from the joint when you work.

[Chrissy_J]

12 hours ago, GazB said:

I have one of the reamers, yeah. I use it to poke through the end a little, but I also remove the needle and put some thinner or cleaner in the cup and then run a piece of paper towel along the nozzle opening so it draws it through, along with some residual paint. Is there a trick to getting a piece of thread through?I

 

Gaz

I'd use a strand of cotton, wet the end and try and push it through like threading a needle. Or you could use the point of a pin or a sewing needle to push it through.

The important thing is not to use anything solid enough that it might make the hole in the needle tip any bigger, as it'll increase the size of your spray pattern - it'll turn your 0.3 tip into an 0.4 or bigger.

[Gorby]

I use these for cleaning out the end of the nozzle:

https://www.amazon.co.uk/TePe-Interdental-Brushes-0-4mm-Pink/dp/B002RUUF4M/ref=sr_1_21_a_it?ie=UTF8&qid=1549218330&sr=8-21&keywords=floss+sticks+dental

 

[bmwh548]

Those work for the everything but the nozzle itself on these airbrushes.