OzVMX Forum

Clubroom => Tech Talk => Topic started by: mx250 on June 04, 2008, 10:35:47 am

Title: Spray Painting in damp conditions.
Post by: mx250 on June 04, 2008, 10:35:47 am
How big an issue is it spray painting small items, say side covers, in cold rainy days such as today (in Sydney)?

Assume, spraying from a can, warming the paint/can in hot water, spraying in a warm covered area.
Title: Re: Spray Painting in damp conditions.
Post by: Paddles on June 04, 2008, 11:12:15 am
if you're using a satin black on a case/cover i would think it'd be ok. i thought the main issue with moisture was the finish on gloss.
Title: Re: Spray Painting in damp conditions.
Post by: OZYKTM on June 04, 2008, 11:20:36 am
Warming the can won't help with that it will just thin the paint a little bit and make it easier to spray but won't help with problems with the weather unless you can control the conditions around the spray area you could run into problems if you don't need to do it straight away i would leave it till you get better weather all paint drying times and recomendations on spraying are worked out on 25c. :)
Title: Re: Spray Painting in damp conditions.
Post by: mx250 on June 04, 2008, 12:15:31 pm
Does the above apply to top coats only or is doing prep work like primers and spray putty also a 'no no'.

Does the weather effect adhersion or finish, assuming good drying conditions/temps.
Title: Re: Spray Painting in damp conditions.
Post by: Colin Jay on June 04, 2008, 01:04:23 pm
From my experience with spray painting (I am no professional) bike parts it is mainly humidity that causes problems, although really low temeratures are not good either.  A lot of primers are hydroscopic, i.e. absorb moisture from the atmosphere and if you use them or spray over them in damp conditions you can end up will rust/corrosion forming under your finished paint work.

If you are able to warm up the shed to a nice mid 20 drgrees (or do it in the kitchen when the boss is not home) and the humidity is not overly high you should have few problems.  If it is too cold the finish could be dull, but that can often be fixed by giving the paint a good polish once it has dried and been given time to harden.

CJ
Title: Re: Spray Painting in damp conditions.
Post by: Oldrodder on June 04, 2008, 03:59:46 pm
Unless you have a spray booth give it a miss, you will end up with humidity blisters: i.e: small water bubbles under the paint.
Title: Re: Spray Painting in damp conditions.
Post by: magoo on June 04, 2008, 05:12:07 pm
The best way to get good results in wet weather is to open the beer fridge and empty contents into mouth. Hopefully, by the time you've sobered up the rain will have stopped, the sun will be shining and all will be happy with the world.
Title: Re: Spray Painting in damp conditions.
Post by: Graeme M on June 04, 2008, 05:16:40 pm
Ummm... But isn't that the same technique you've offered up for every other tricky question on this forum? Hmmm....
Title: Re: Spray Painting in damp conditions.
Post by: DJRacing on June 04, 2008, 05:52:04 pm
How cold are we talking? Its more a sudden drop in temp that will make the paint flash (inconsistant sheen/discolouring). You can do all your prep work, priming etc.