david.hill64 Posted March 9, 2014 Share Posted March 9, 2014 I have used Humbrol satin black aerosol on my 0 gauge B1 model, applied the transfers and the used a coast of Humbrol satin aerosol varnish to seal it. Unfortunately the finish is very milky in appearance. I have not used acrylics before, but took time to shake the can well before using. Does anybody know: 1 What went wrong and how I can prevent it next time, and 2 how to recover the situation? Thanks David Link to post Share on other sites More sharing options...
micklner Posted March 9, 2014 Share Posted March 9, 2014 Blooming due to spraying in a cold/damp atmosphere. Warm the can in hot water (not boiling) hopefully it will disapear with another thin coat of varnish. Link to post Share on other sites More sharing options...
sandwich station Posted March 9, 2014 Share Posted March 9, 2014 You should be able to make it good by re-coating it. As mentioned above, could be cold/damp or even a high humidity day that caused it. Link to post Share on other sites More sharing options...
david.hill64 Posted March 9, 2014 Author Share Posted March 9, 2014 It's certainly not due to cold; I'm in Bangkok and even with the air conditioning on its 26 degrees in the room! Could be humidity though. Thanks for the suggestions. Link to post Share on other sites More sharing options...
david.hill64 Posted March 9, 2014 Author Share Posted March 9, 2014 Well it's a pleasant 33 degrees at present so I have taken it outside and re-sprayed it. Link to post Share on other sites More sharing options...
RMweb Premium Trainshed Terry Posted March 9, 2014 RMweb Premium Share Posted March 9, 2014 Well it's a pleasant 33 degrees at present so I have taken it outside and re-sprayed it. Let us all know if it worked and post a picture. Terry. Link to post Share on other sites More sharing options...
david.hill64 Posted March 9, 2014 Author Share Posted March 9, 2014 Let us all know if it worked and post a picture. Terry. Slight improvement thanks. Still not as it should be though. Sorry about the pool towel! I might try a different type of varnish if I can get a spray can: I don't have my airbrush and compressor here. I have been using some Japanese solvent based acrylics (Mr Color) on a different project. They are the best paint I have ever used, but I worry about what will happen if I spray them on top of the Humbrol. I suppose I can check on some scrap first. Link to post Share on other sites More sharing options...
RMweb Premium Trainshed Terry Posted March 9, 2014 RMweb Premium Share Posted March 9, 2014 Slight improvement thanks. Still not as it should be though. Sorry about the pool towel! I might try a different type of varnish if I can get a spray can: I don't have my airbrush and compressor here. I have been using some Japanese solvent based acrylics (Mr Color) on a different project. They are the best paint I have ever used, but I worry about what will happen if I spray them on top of the Humbrol. I suppose I can check on some scrap first. Can you use as a base for weathering the model as it dose look quite convincing for weathering. Terry Link to post Share on other sites More sharing options...
david.hill64 Posted March 9, 2014 Author Share Posted March 9, 2014 Can you use as a base for weathering the model as it dose look quite convincing for weathering. Terry Probably: It looks worse in the photos than to the naked eye. Link to post Share on other sites More sharing options...
Keith George Posted March 9, 2014 Share Posted March 9, 2014 I have also had the same problem with Humbrol acrylic varnish, I like their paint but not their varnish. !! I now use Tamiya acrylic varnish and have had no problems at all with that. Keith. Link to post Share on other sites More sharing options...
sandwich station Posted March 9, 2014 Share Posted March 9, 2014 I use Humbrol acrylic varnish usually with no problems but then I am in Melbourne where the humidity is generally quite low. I do know, that if you apply it a little on the heavy side which means it takes longer to dry, sometimes it will bloom. Link to post Share on other sites More sharing options...
BlackRat Posted March 9, 2014 Share Posted March 9, 2014 Try a blast with a hair dryer..........it sometimes works. If not, it's a strip and re spray as its impossible to eliminate. Link to post Share on other sites More sharing options...
AngryMeerkat Posted March 10, 2014 Share Posted March 10, 2014 The blooming effect is caused by moisture trapped in the paint, usually caused by damp or humid conditions. You can sometimes dry it out by gently warming the area up with a hair dryer, if that doesn't work then the blooming is there until it is stripped and repainted. For what it's worth, you shouldn't just coat over this blooming, as the trapped moisture will eventually find it's own way out, usually taking the surrounding paint with it. How do I know? I've had the front wing of a car decide that it no longer wanted any lacquer on it thanks to a relatively small bloom. Mark Link to post Share on other sites More sharing options...
david.hill64 Posted March 12, 2014 Author Share Posted March 12, 2014 Well, after two days on the washing machine sunbathing, I think there is an improvement. But is it wishful thinking? I will post pictures at the weekend. David Link to post Share on other sites More sharing options...
BRera80s Posted March 13, 2014 Share Posted March 13, 2014 I've had exactly the same problem with Humbrol matt varnish. I sprayed five locomotive bodies and I tried drying them out on a radiator set at a low heat for two days and there was no improvement. I managed to scrub some of it off using a Dettol solution but in the end I resprayed all of the locos. It was a costly mistake and I will never use Humbrol varnishes again. Their paints are excellent though. Link to post Share on other sites More sharing options...
BlackRat Posted March 13, 2014 Share Posted March 13, 2014 Hair dryer. Link to post Share on other sites More sharing options...
david.hill64 Posted March 14, 2014 Author Share Posted March 14, 2014 Hair dryer. Will give it a go tonight. Thanks for the suggestion. The sunbathing definitely made an improvement and the tender appears to be OK now. The cab front is the worst affected. Link to post Share on other sites More sharing options...
Nimbus Posted March 14, 2014 Share Posted March 14, 2014 Hair dryer. Yes. I believe Sir Alex has time on his hands nowadays... The Nim. Link to post Share on other sites More sharing options...
david.hill64 Posted March 16, 2014 Author Share Posted March 16, 2014 Hair dryer. The hair dryer treatment was interesting: it went more milky when hot, but definitely improved after it had cooled. Thanks for the suggestion. I'll take some photos and post later. Link to post Share on other sites More sharing options...
cobach47 Posted March 26, 2014 Share Posted March 26, 2014 i have been using games workshop purity seal - a satin acrylic varnish at £9.50 for a large can. i have had the same problem because of temperature variations ( store your cans indoors if possible ) and have had some success by using old type johnsons" klear" over the milky finish this can restore the original finish then use the purity seal but don't get it too wet just a light spray should do it, i get a good factory finish using this product. Link to post Share on other sites More sharing options...
david.hill64 Posted March 27, 2014 Author Share Posted March 27, 2014 Thanks all for the continued interest and suggestions. Unfortunately I've been unwell for a few days and not able to do anything. Interestingly it looks like the finish is getting better: The loco has been in a hot room - it's 36degrees outside and I suspect considerably warmer in the small modelling room. As promised before: more photos to follow. Link to post Share on other sites More sharing options...
david.hill64 Posted April 21, 2014 Author Share Posted April 21, 2014 It has been a while posting as I have been away on business. The hairdryer had improved things a lot, but there was some roughness to teh surface that I did not like so I tried something else. I have been using some solvent based Japanese acrylic paint which is very good. I wondered what the thinners would do to the finish. The results were remarkable. In close-up you can see the boiler and smokebox has been treated, but the boiler fittings and smokebox in front of the conduit has not been. I think that with some light weathering on top the end finish will be acceptable. Link to post Share on other sites More sharing options...
AngryMeerkat Posted April 21, 2014 Share Posted April 21, 2014 Hi David, glad you got a finish you're happy with. It's always a nice feeling when a job comes out right in the end, and the finish on your model looks excellent in the pictures. You say there was some roughness to the finish before you used thinners. Was this apparent before you used the hair dryer or was it the hair dryer that caused it? When you used thinners on the surface, what did you actually do? If the 2 are related as I think they are then you may have just solved a massive problem we've been struggling with in work. Thanks, Mark Link to post Share on other sites More sharing options...
RMweb Gold Corbs Posted April 21, 2014 RMweb Gold Share Posted April 21, 2014 Phew! Really glad you didn't have to strip it all back! Link to post Share on other sites More sharing options...
david.hill64 Posted April 21, 2014 Author Share Posted April 21, 2014 Hi David, glad you got a finish you're happy with. It's always a nice feeling when a job comes out right in the end, and the finish on your model looks excellent in the pictures. You say there was some roughness to the finish before you used thinners. Was this apparent before you used the hair dryer or was it the hair dryer that caused it? When you used thinners on the surface, what did you actually do? If the 2 are related as I think they are then you may have just solved a massive problem we've been struggling with in work. Thanks, Mark I think the roughness developed, possibly as a result of the hairdryer, but also as a result of being in a very hot room in Bangkok when I was away on a business trip. It must have been cooking nicely! I assume that the roughness came from trapped moisture bubbling out. I used a cotton swab - the type used for ear cleaning - dipped in the thinners and gently rubbed (and I mean gently - more of a lick than a rub) a thin layer of thinners over the surface. I let it do its own thing: essentially I think it 'melted' the varnish and keyed into the paint. The treated surface is certainly smoother. Hope this helps. Phew! Really glad you didn't have to strip it all back! Not half as glad as I am!!! Link to post Share on other sites More sharing options...
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