discussion H&S Ultra problems

[Gern]

Hi guys. Sorry about this, but I'm back to pester you with a problem.

As the title says, I have a H&S Ultra airbrush. I bought it from John a couple of years ago and it's been doing a great job for me until last week. I found I was getting paint from the spray even after I'd done a thorough clean.

Yesterday, I had the same problem and decided to completely strip down the brush. When I did, I found the entire trigger mechanism and the retaining spring and collar covered in paint. Correct me if I'm wrong, but there shouldn't be any paint in that area of the airbrush should there?

Could I have a damaged seal somewhere and, if so, how can I fix it?

 

[Guest]

Hi Dave .
No you shouldn't, sounds like paint traveling up the needle . Your thoughts of a damaged seal seem right . If you look in the instruction book you should find a diagram of the unit, along with some help about common problems. You can buy sets of seals .
John .

 

[Gern]

Hi John.

I've had a good look through the destructions as you suggested. There's no mention of any sort of seal anywhere except the one on the nozzle itself. I remember when I bought it, I questioned John about a seal for the aircap and he contacted H&S who said basically they don't supply them with the Ultra model! John was a star and sent me a couple of seals for the aircap, and as I said it's been working fine until last week.

I've stripped it down again and had a good look inside. There's no visible evidence of any damage and no sign of any seals except on the nozzle and aircap. I'm baffled that the problem suddenly started unless .......

I'm trying to help my grandson learn some of the art of modelling. He's used my airbrush in the past but he's always been very heavy-handed on the trigger. I usually spray at around 25psi, but I recently reduced the pressure to about 12-15 psi in the hopes that my grandson won't flood his kits with paint. Is it possible that the lower pressure is allowing the paint to flow back up the needle?

Just in case it may be the paint at fault, I only spray with VMA and Tamiya acrylics, thinned with water and X-20A respectively.

 

[Si Benson]

Found this break down diagram which shows a second seal...123450. I don’t own one but would assume it’s a PTFE ring?
View attachment 315011

 

[Tim Marlow]

Hi Dave
This may be due to inexperienced use. Is it possible that your grandson is releasing the air before the paint trigger when holding the airbrush point upwards, allowing paint residue to run back up the barrel? If he is heavy handed on the paint feed there may be a fair bit of paint in the chamber when the air goes off.
Cheers
Tim

 

[coachman]

Hi Dave, had a similar problem with my Eclipse, I tightened the seal and much better. The part shown on the breakdown that Si posted, No.123471
would , I imagine, do the same job. Just tighten gently and you should feel more resistance when inserting needle. Hope this solves it. John

 

[Wouter]

Had the same with my H&S couple of years ago, it is a seal indeed, regular wear 'n tear. It's part 123450 on Si's photo which needs to be replaced as Si mentions. H&S sell replacement seals for their airbrushes. That will do the trick.

Cheers

 

[Guest]

Dave
Well that seems to be the problem, seal and maybe trigger happy Grandson :smiling: Good to rad he's takening an interest .
Let's hope a new seal solves the problem . It would be nice to read that is does.
John.

 

[Gern]

Si: Alas. The seal and it's retainer (parts 123450 and 123471) shown in your diagram are not in the A/B I have (and are not shown in the instruction booklet). Even so, if that seal is behind the trigger assembly, it wouldn't stop the paint getting to the trigger; and I can't see any evidence of screw threads where they might fit between the paint cup and the trigger

John (coachman), Wouter and John (Race): I wish it was just a case of getting a replacement seal. I have no issues about replacing parts 'cos of general wear and tear, but I don't have a seal to replace. :crying::sad:

Tim: He could be doing just as you suggest. I'll try the brush myself and do that to see if it is the problem.

 

[Si Benson]

Oh sorry Dave, I though you said you had an H&S ultra:thinking:

 

[Gern]

Oh sorry Dave, I though you said you had an H&S ultra:thinking:

I do! At least, that's what it has printed on the main body, along with a serial number 28585 which I'm just about to go and check out.

 

[Gern]

I do! At least, that's what it has printed on the main body, along with a serial number 28585 which I'm just about to go and check out.

Just been on the H&S website. I found the same diagram you did Si, but no mention ANYWHERE of an Ultra with that serial number. Guess I'll have to contact them and see what they tell me.

 

[Si Benson]

The plot thickens:upside:

 

[Guest]

Confusing to say the least Dave.
I was of the same opinion as Si. No doubt H&S will be able to pin point the problem. Let us know please.


John.


the Sam

 

[Gern]

Many weeks later .....

I've had a play around with my A/B and I haven't been able to replicate the problem. I suspect Tim is right and maybe it was accidentally caused by my grandson. I'll be trying some painting later so I'll have to see how it goes.

I did contact H&S. They told me the number on my A/B is just a serial number for it. Then they sent me the diagram from their website asking which parts I was missing - 123450 and 123471 which I cannot see anywhere on my A/B. That's all I've heard.

Meanwhile, back at the ranch ....

While I was testing it using just water, spraying at about 25 psi and with the 0.4 mm set-up, I noticed drops of water gathering on the rim of the air cap. These eventually fell off into the spray. I can see that causing a problem if it happens with paint. Any ideas?

 

[Mr Bowcat]

Shouldn't be a problem Dave, if it was paint it would dry on the cap rather than build into a droplet. I get that with my H&S Evo when I'm blowing water or IPA through to clean, never had a droplet when using paints.

 

[Guest]

Dave
Could you post a photo of the AB and the nozzle end complete. thanks
John .

 

[Gern]

Here you go John. Let me know if it's not what you wanted to see. My photography skills are limited, but if there's any other views you want, I'll give it a try.

View attachment 318912

 

[Guest]

Here you go John. Let me know if it's not what you wanted to see. My photography skills are limited, but if there's any other views you want, I'll give it a try.

View attachment 318912

Thanks Dave.
I was going to ask about the nozzel but when I went on line to look for that parts list I came across an old posting from you in 2016. Feb. Has this problem started again or did the seals that John got not work ?
John .

 

[stillp]

Then they sent me the diagram from their website asking which parts I was missing - 123450 and 123471 which I cannot see anywhere on my A/B.

Dave, if it is the same as the H & S Infinity, 123450 is a set of 3 white PTFE rings, like short slices of tubing. They fit inside 123471, which is a brass threaded collar with a screwdriver slot. Tightening the screw pushes the PTFE seals into a taper, which should tighten them onto the needle.

Pete