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altec
03-26-2005, 10:24 AM
If you need paint to dry really really fast. Get what your painting warm with a heat gun then spray the paint. Do this on all the coats and you well be done in no time at all.

ZeD
03-26-2005, 12:06 PM
Using a heatgun is great for stripping paint too. Dunno if its a good idea to use it for faster drying time though.

Bum
03-26-2005, 06:42 PM
A warmer surface will help your dry time a bit but be careful if you use it after the first coat. Like ZeD said, they are used to strip paint. Also avoid using it to dry the paint directly (like a fan). It could work but you can VERY easily blister wet paint with the heat these put out.

ZeD
03-27-2005, 06:21 AM
now that I think about it it will also cause bubbles and runs. It cant be easy to get a uniform dry using a heatgun

jonopaul01
04-01-2005, 05:03 PM
I suppose this is why they say you need to follow the advice at your own risk. If anyone tries this and finds that it causes problems then write in and tell us. Of course if it works then also write and tell us.

fishies
04-01-2005, 05:07 PM
A heat gun would dry paint well, with a large enough diffuser. As long as you aren't holding the gun right up to the paint, on low power (if possible), making passes, like with a spray can will aid in your drying. Paint quality is a factor here.

Remember the big name auto makers (high end) all bake the paint onto the cars.

jonopaul01
04-01-2005, 05:12 PM
I thought that auto companies used electrolysis to apply paint to their cars. Or is that crome? Anyway, I suppose if you did not hold it right up to the paint it would help. But is it really that necassary to speed up the paint drying that little bit, especially when you consider the fact that you might ruin your paint, which will need to be redone and will in the end waste far more time than it would have gained?
I would love to see if this does actually work for anyone.

Frakk
04-01-2005, 05:20 PM
considering physics and chemistry, all reactions occur much faster when heated due to the faster motion of the molecules. try to disolve sugar in cold water. it takes a long long time. disolving it in your hot tea takes about 3 seconds, and some of the sugar will be disolved before it can hit the bottom of your cup. same thing with evaporation(drying). a good example when it rains in the morning on a hot day. in the shadows you will still see the wet sidewalk and road, but on the hot sunny part it is completely dry. heat will speed up drying significantly, but getting greedy will ruing the paintjob.

siege
04-01-2005, 08:36 PM
if you want to try this, maybe try heating it from the other side of the panel if its not painted...just to get it warm all over...just a thought - never tried this or would have any reason to. Now if I was using auto paint and could heat the room, that'd be a different story.

edit: or hell, try pointing a couple heatlamps at it :)

Crimson Sky
04-02-2005, 12:52 AM
Any light warming would help speed the (to the touch)drying process really. The curing takes place over time, and nothing beats patience--its agonizing i know but its worth it.

Guttenaffe
04-02-2005, 01:09 AM
I have a "drying room" I use my bathroom to dry paint quickly.

How-to:
1) Before the painting shut the door and turn on you shower hot as it will go till steam has lightly covered the top of the room and turn it off
2) Turn on your bathrooms exhaust fan, open the door leave, and shut the door behind you leaving the fan on and hopefully the light off to save power
3) Wait about 15 to 30 mins for the room to lose the extra humidity, place a self-contained oil radiator space heater in the bathroom and turn it on high and let it heat the room
4) Go add your coat of paint to what ever your painting
5) Now quickly place it inside the dust free heated bathroom

Your paint will dry quit a bit quicker and will require less sanding cause you should have less dust falling on it, the steam made it fall out of the air except for what you stir up when moving about inside there.

The optimal place would be a heated, vented, and air filtered painting booth, but some of us have to make due with what we got.

fishies
04-02-2005, 01:18 AM
I thought that auto companies used electrolysis to apply paint to their cars. Or is that crome? Anyway, I suppose if you did not hold it right up to the paint it would help. But is it really that necassary to speed up the paint drying that little bit, especially when you consider the fact that you might ruin your paint, which will need to be redone and will in the end waste far more time than it would have gained?
I would love to see if this does actually work for anyone.

chrome is elecroplated. Paint is sprayed, then baked on, in a heat room. the heat is uniform, and passive, in the sense that the heat is blown in with fans. usually it's heat lights.

If you had a paint booth, you could add a heat lamp.

ahhh..... paintbooth... my wife would commit homicide in the garage if I built one.... off topic... derailment....

back to our regularly scheduled posting...

fishies
04-02-2005, 01:23 AM
If you need paint to dry really really fast. Get what your painting warm with a heat gun then spray the paint. Do this on all the coats and you well be done in no time at all.

After reading this post, it occurs to me that this is a real bad idea.

The contents of the paint can are under pressure. Adding heat will cause the contents to expand, causing more pressure. Too much pressure and boom.

If you want to heat the can, use it first, then place the half used can in a bucket of hot from the tap water. The heat transfer isn't as severe as with a heat gun. (This is a trick used in the auto service industry to quickly fill your auto's a/c refrigerant.)

So, safety first, boys and girls. No one needs to read about a fatality due to dangerous modding tips.

Guttenaffe
04-02-2005, 11:54 PM
fishies, I'm not trying to be contrary even though that is good advice about paint cans being under pressure, but I do believe he was saying to heat the surface you will be painting not the can you are painting with.

I'm not to sure about heating the surface to be painted as well though, seems to me it would cause the bottom of the paint to dry faster and make it easier to get "runs" in the paint, but I am no expert. Anyone here know if this has some truth to it?

fishies
04-03-2005, 11:05 AM
fishies, I'm not trying to be contrary even though that is good advice about paint cans being under pressure, but I do believe he was saying to heat the surface you will be painting not the can you are painting with.

I'm not to sure about heating the surface to be painted as well though, seems to me it would cause the bottom of the paint to dry faster and make it easier to get "runs" in the paint, but I am no expert. Anyone here know if this has some truth to it?


A couple degrees makes a huge difference. the paint adheres better, and dries quicker. Anything over a couple degrees above ambient will do little to help your paint, and it may ruin it by not allowing it to adhere to the surface, and flaking off.

Once the paint is applied, depending on the quality (no tremclad here) heat can be used by way of heat lights. (Automotive industry bakes it on at 200-400 degrees farenheight.)

Using heat lamps can be dangerous, as they produce amounts of heat. Make sure flammable materials are out of the area of heating. Space heaters are worse to use since they use a fan to send out their heat. The fan can cause the dust to stir and land on your paint. Not fun.

Remember, boys a nd girls. Read all your safety warnings first.

Zuke
04-06-2005, 06:17 PM
I've often found the best prep for plastic thats being painted is also the best way to heat it up: I wash it! I put it in the top rack of the dishwasher with the dry cycle on and it not only clears the plastics of any oils and residue that might mar the paint, but it also heats it to a nice even temp. Once the cycle is done, use my latex gloves and take it straight to painting. This can even help open up the plastic so it will take paint a tad better (forgoes the need to roughen up some surfaces).

<offtopic> the top rack is also a great place to make an easy poached salmon! </offtopic>