Achieving a perfect finish from rattle cans

[KeithT]

One good tip I was given on the Forum about preventing 'creep' under the masking tape is to apply the tape, press down firmly and then respray along the edge with the 'masked-off' colour and allow to dry, that way it forms a seal and prevents the new colour bleeding under the tape.

Another cheap source of a Lazy Susan is IKEA.

 

[ge_rik]

One good tip I was given on the Forum about preventing 'creep' under the masking tape is to apply the tape, press down firmly and then respray along the edge with the 'masked-off' colour and allow to dry, that way it forms a seal and pevents the new colour bleeding under the tape.

Another cheap source of a Lazy Susan is IKEA.

That sounds like a useful tip - not thought of that. We need to parcel up all these tips and post them somewhere centrally

Rik

 

[ge_rik]

Just been reflecting on the various postings and it sounds as if there are some fundamental flaws in my painting technique. My process in painting is:

1. Apply masking tape
2. Apply two coats of primer
3. Let dry, then rub down to provide a smooth surface
4. Apply final coat of primer and let dry
5. Apply two coats of top coat (sometimes three coats)
6. Let dry and rub down
7. Apply one (sometimes two) coats of top coat and let dry
8. Remove masking tape
9. Apply transfers / lining etc
10. Apply two coats of varnish

The guidance on removing the masking tape seems to suggest that fewer coats of paint are needed or that tape needs to be removed and reapplied at intervals through the process.

I'd be interested in the stages others go through in their painting process to see how they compare. Am I making it too complicated - or are there some additional stages I'm missing?

Rik

 

[3Valve]

This was masked off with Duck low adhesion masking tape from Halfords. They do sometimes have branded "low adhesion" tapes in stock (Duck, Harris etc), so it's always worth a look if you're already in there looking for yer paint. (Yep the paint was Halfords too).

 

[gregh]

It's all very well telling us to get an air brush, but the thread started out on 'how to use rattle cans'. I've gone 60 years without one, and I've seen my wife have problems with clogging and splattering with hers.
There have been some very good hints so far that no doubt apply equally well to both systems.
But my real nemesis is this sort of problem on STYRENE (is that Plasticard to you?) - crazing. This pic is of a really bad example but as it was a water tank I decided to leave it.

I thought it may have been due to styrene dust on the surface, but no matter how well I wash and dry before painting, it still sometimes happens. Usually on horizontal surfaces. Now I'm wondering if it is to do with humidity. Or paint too thick?

Does anyone have the answer?
Does it happen with airbrushes??

I'm about to final coat my loco, just waiting for it to fine up (reduced humidity). The undercoat crazed in just one small spot on the footplate.

 

[ge_rik]

Thanks Greg. You're right, my original thread was about rattle cans and how to get the best finish.

My problem still relates to whether masking tape needs to be continuously removed and then reapplied between each coat or am I applying too many coats. Should I prime plasticard or just go straight to two top coats and that's it?

The only time I got crazing like Greg's was when, I think, I applied the paint too thickly. There seems to be an art in getting the balance between too thin, too thick and just right. Is it more difficult to control with rattle cans?

Rik

 

[steve parberry]

I think thats a case of two types of paint reacting with each other, the top coat is dissolving the primer, or the primer is not suitable for the plastic surface.

 

[400Parker]

Chris Bird wrote an excellent guide on http://www.gardenrailwayclub.com/workshop/painting---the-easy-way < Link To Garden Railway Club called "Painting locos - the easy way". It's worth a look. As for painting on styrene, it's always a good idea to try your paint on a piece of scrap material first. Some paints react badly with styrene.
Happy painting!
Steve

 

[ge_rik]

Chris Bird wrote an excellent guide on http://www.gardenrailwayclub.com/workshop/painting---the-easy-way < Link To Garden Railway Club called "Painting locos - the easy way". It's worth a look. As for painting on styrene, it's always a good idea to try your paint on a piece of scrap material first. Some paints react badly with styrene.
Happy painting!
Steve

Thanks for the link, Steve. I'm all for easy.

Now you mention it I had a disaster recently with a handpainted secondhand kitbuilt loco which I tried repainting. After rubbing it down I decided not to prime it as I had not gone back down to bare plastic. I gave it a coat of Humbrol acrylic spray and the result was like paint stripper. Clearly the solvent in the Humbrol spray reacted with whatever it had been painted with previously (ironic if it had been Humbrol enamels).

Rik

PS - Just read through the article above and he states that whereas enamels will overpaint acrylics, vice versa is not the case. Looking at the instructions on the can it does suggest testing first. Another case of not reading the instructions ...........

 

[KeithT]

Thanks Greg. You're right, my original thread was about rattle cans and how to get the best finish.

My problem still relates to whether masking tape needs to be continuously removed and then reapplied between each coat or am I applying too many coats. Should I prime plasticard or just go straight to two top coats and that's it?

The only time I got crazing like Greg's was when, I think, I applied the paint too thickly. There seems to be an art in getting the balance between too thin, too thick and just right. Is it more difficult to control with rattle cans?

Rik

My experience in spraying using masking tape is limited but I have oversprayed surfaces several times and only removed the tape after the final coat.
I always remove the tape as the final coat is 'going off' and not when fully dry otherwise it can 'tear' the last coat.

 

[3Valve]

Thanks Greg. You're right, my original thread was about rattle cans and how to get the best finish.

My problem still relates to whether masking tape needs to be continuously removed and then reapplied between each coat or am I applying too many coats. Should I prime plasticard or just go straight to two top coats and that's it?

The only time I got crazing like Greg's was when, I think, I applied the paint too thickly. There seems to be an art in getting the balance between too thin, too thick and just right. Is it more difficult to control with rattle cans?

Rik

My experience in spraying using masking tape is limited but I have oversprayed surfaces several times and only removed the tape after the final coat.
I always remove the tape as the final coat is 'going off' and not when fully dry otherwise it can 'tear' the last coat.

Use the same method myself Keith, seems to work OK for me.

 

[ge_rik]

My experience in spraying using masking tape is limited but I have oversprayed surfaces several times and only removed the tape after the final coat.
I always remove the tape as the final coat is 'going off' and not when fully dry otherwise it can 'tear' the last coat.

Use the same method myself Keith, seems to work OK for me.

Thanks chaps. I'll certainly give that a go. I've got two locos in the paintshop at the moment. One is just about to have its last coat so I'll try this out.

The other is having to have some remedial work to touch-up where the masking tape has lifted/torn the paint to the extent I'm using filler and rubbing down to try and get an even coat. This is the loco which reacted bady to the Humbrol acrylic spray (see post 32) so it's become a catalogue of disaster............

Rik

 

[Dave Hub]

Hello all,

firstly a good thread with lots of nput form some very experienced moddlers, Compared to peolpe like Maybach I am amateur but here is my 2 pence worth.

I use rattlle cans, I treid an airbrush, all be it with aerosol gas but had many problems getting the piant to the right consistance. also the amount of effort to clean all the air brush out after every use drove me nuts and added an hour on to every task.

I tend to use rattle cans, esp those from car stores such as Halfords. I have also used some of the model specific ones for Rail blue when halfords do not match it.

+Firstly Make sure your model is clean with no dust. do not use fairy liquid.

+ mask all area you don't want to be sprayed, low tack tape, and maskol for the windows.

+Warm your primer and the room / garage your spraying in.

+Always use the appropriate primer, For plastic I use halfords plastic primer, for bare metal I use acid etch primer. If the surface is very glossy rub it with some 800 grade paper, this will allow the primer to key to the surface.

+When spraying the can should be about a foot (12") away from the model, too close and you'll get runs, too far and paint atoms may start to dry before adhering to the model. I never start spraying directly at the model, Start off to the edge away from the model and once your spray has started then move the spray on to the model.

+Wait, 24 hours minimum, use this time.

+ Once the primer is dry. Repeat the warming steps. Then its time to paint, make sure can is well shaken, and warm, again start spraying slightly away from the model until the spray actually starts. Once the spray steam has started gently move this towards the model. Follow the same principle as the primer, about a foot. It'll take some practice as all paint brands differ slightly in their consistance and therefore may run in different circumstances.

+ I usually build up 3 light coats, with the model on a lazy susan (ikea £5.00).

+Wait about an hour before removing the masking tape.

+wait about a week for paint to harden pick a varnish, and repeat the process again with varnish.

questions that were asked: do I re apply the masking tape each time. Nope I leave it on through the painting stage otherwise I may add it slightly different each time. (maskol advises not to leave it on for more than 48 Hours).

-----------------------------------------

Like I said I'm not as good as some peope but I do use rattle cans and I am happy enough with my results. Here are a few threads where my use of ratttle cans can be seen:


PIKO 218 using railmathc spraycans. Slightly different and more aggressive spray than halfords, but with practice got a decent finish:
http://www.gscalecentral.net/tm?m=5793&high=PIKO+218


LGB LCE using halfords red, and silver:
http://www.gscalecentral.net/tm?&m=33700&high=LCE&mpage=4

My current unfinished ML4000 project agian using halfords spray cans:
http://www.gscalecentral.net/tm?&m=73453&high=LCE&mpage=2

 

[MAYBACH]

The world of "compatible" paints is a nightmare, even when using paints that should be fine you can get issues! I always try to stick to one manufacturer per model if possible, but when you start working on models that have already been painted you are on shaky ground!
I will often wipe over the model with cellulose thinners on a clean cloth to remove any potential contaminates.
Many acrylic sprays contain the same chemicals as cellulose paints which is what causes them to react on pre painted surfaces, Halfords will do this on certain paints!!!!

The cans verses airbrush thing is simply a matter of how good you want your model to look, this may upset some people but if you are after a real top paint job on a finely detailed model, you have to use an airbrush as cans just can't achieve the fine and controlled spray. They may be fine on simpler models (coaches) or if you have a lower expectation of a "nice paint job".
This is not intended to offend anyone, just my opinion as a model painter, we ALL have very different idea's and standards, my background is highly detailed fine scale stuff.

I would never leave the masking tape on a model, you should remask if further coats are needed, it is a shortcut to leave it, and you don't get top results with shortcuts!
So as regards the best advice for cans, get the model clean and warm, warm the room and the cans, apply the paint thinly all over and slowly build up the coats, "lovingly" peel off any tape as the paint just starts to dry, then LEAVE IT ALONE

Cheers
Rob

 

[ge_rik]

Thanks Dave and Rob

Intersting that there are differing opinions on the masking tape issue. I'll certainly make sure I use proper model makers masking tape and although it's too late now for the paint job I'm half way through, I will have a go at removing and replacing the tape between coats on the next paint job - having had a disaster. For the ongoing paint job I will try removing the tape while the final coat is tacky.

I'll also have a go at warming the cans - never done that before - was worried they might explode I suppose. I do have a fan heater in my workshop - so will build up a fug before spraying. The only problem is I open the doors when spraying to release the fumes so that may defeat the object, particularly as winter is on its way.

There's some really useful pointers in this thread - thanks to all who have contributed so far. If I ever reach the point where I feel I've cracked it, I will aim to share my experiences for those who follow.

Rik

 

[Dave Hub]

Well I think Rob nailed it on the head, He's been doing this for years, and paints exquisite and expensive models, I re-hash models in bizarre colours for my own pleasure, and at the end of the day if its your model only you know what standard you want to achieve. Some people will look at my efforts and say wow that looks good, others will point to the erors of my ways.

the key things are that we do agree on, is to take time on the the basics, masking, and making sure model is clean, and never spary cold. Always practice on cheaper items before painting your prized favorite loco.


P.S. Rob no offence taken having seen the quality of models you produce, I expect nothing less than a professional finish. Maybe one day I'll stop being lazy and give airbrushing another go.

 

[pugwash]

Airbrushing is just as easy as cans, for small items even easier.
I too bought this RDG tools set:
http://www.rdgtools.co.uk/acatalog/info_45643.html
which for £55 is a lot of kit. I had some trouble with clogging of the needle (using Tamiya acrylics) so ordered a cleaning kit (like little bottle brushes and reamers) plus 3 spare needles in varing sizes - the smallest one I can't even see the nozzle, I have to look through the magnifier! Anyway a bottle of Tamiya thinner is on its way from Germany as I can't get it sent from GB by law according to my paint supplier:
http://stores.ebay.co.uk/Lendons-Of...11161823&_sid=312836773&_trksid=p4634.c0.m322 < Link To http://stores.ebay.co.uk/...;_trksid=p4634.c0.m322
so when it arrives things should be hokey-cokey!
One joy about this setup is no propellant gases are used (airbrush propellant cans use gas, not air) and acrylics are water based althought the thinner has IPA (IsoPropyl Alcohol) in it for a better mix. Some people recommend thining with anything from tap water to, well, anything. Most agree IPA helps in the mix.
I'm a newbie to airbrushing but I wish I had bought one 30 years ago, and the more you do the more fun it gets and consequently more adventurous. You can get hooked, but not on the fumes!

Forgot, I always spray all over (the model!) with matt acrylic fix, not so much to protect the paint as to make any unpainted plastic matt too

 

[pugwash]

I just had an idea
Wouldn't it be possible for some of the airbrush aces to do 1 day seminars? Like open days but learn airbrushing?
I would offer but I [strike]don't have enough beer for you all[/strike] am a bit too far away
Just a thought :thinking:

 

[gregh]

Dave Hub's reply (post #36) says it all.
Brilliant - thanks very much for the concise summary. I agree with everything in his list.
BUT I still sometimes get that crazed finish on parts. Guess no-one has the answer to that.

 

[ge_rik]

Yes, thanks guys and gals for all the help and guidance. I think I know more now than I did when I started the thread. All I have to do now is put it into practice.

I'm still somewhat wary about using masking tape - but I like the idea of using maskol for the windows. Might try using that for some of the smaller or more inaccessible areas as well.

Rik