Warming spraycans in dehyddrator

[ERIK88]

how long do you guys warm spraypaint cans in the dehydrator?

[hooknladderno1]

DO NOT WARM YOUR SPRAY CANS IN THE DEHYDRATOR!!! Your best bet is to put a large container of water in your microwave and heat it for 1-2 minutes. Take the container out of the microwave and place your spray can in the water for a couple minutes. It is that easy AND safe! Good luck.

David

[PappyD340]

  On 10/27/2013 at 4:30 AM, hooknladderno1 said:

DO NOT WARM YOUR SPRAY CANS IN THE DEHYDRATOR!!! Your best bet is to put a large container of water in your microwave and heat it for 1-2 minutes. Take the container out of the microwave and place your spray can in the water for a couple minutes. It is that easy AND safe! Good luck.

David

Yep that's what I do, just a few minutes is all you need!

[wagonmaster]

I usually run the fawcett till it is hot then hold the can under. when the can is warm remove from the water and shake it. I repeat until tthe can no longer turns cold when you shake it.

Tim

[High octane]

I put some hot tap water into a pot and put the can in the water for 6 or 7 minutes and then spray paint. It seems to work good as I've been doin' it for years and the paint flows smoothly.

[ScaleDale]

Toss the can in the sink and turn on the hot water. Use the facilities and it will be ready to go.

Dale

[MAGNUM4342]

  On 10/28/2013 at 3:00 AM, wagonmaster said:

I usually run the fawcett till it is hot then hold the can under. when the can is warm remove from the water and shake it. I repeat until tthe can no longer turns cold when you shake it.

Tim

X2

[Pete J.]

  On 10/27/2013 at 4:30 AM, hooknladderno1 said:

DO NOT WARM YOUR SPRAY CANS IN THE DEHYDRATOR!!! Your best bet is to put a large container of water in your microwave and heat it for 1-2 minutes. Take the container out of the microwave and place your spray can in the water for a couple minutes. It is that easy AND safe! Good luck.

David

Please explain why you feel this is a dangerous process and your is safer.

[hooknladderno1]

Spray cans are metal. Spray cans contain compressed flamable gases. The benefit of smoother flowinng paint can be accomplished by a much safer means while not sacrificing serious injury, death, fire, or explosion. That about sums it up... : )

[Pete J.]

Ok, but heating the can by any method is equally safe/unsafe. A food dehydrator is no more dangerous in than doing it in water. Food dehydrators heat to a far lower temperature than the safety limit of aerosol paint can. The danger comes from sudden release of the propellant and paint. That danger is much higher when you accidently puncture the can than it is from the can bursting from excess heat. Lastly the danger is primarily from having an ignition source nearby not the bursting can. Read this web site. It will not change your mind about the inherent danger of a rattle can, but it will give you a better idea about the true dangers associated with rattle cans and how to use them safely. http://www.chemaxx.com/aerosol8.htm

[ERIK88]

I figured at if its gonna blow up, at least it will be inside an enclosed surface (the dehydrator itself). Ive done the hot water method, I dont think its as efficient.

[Bruce Poage]

Been modelling for many decades. Warmed spray cans in warm water sink or container during 5th decade. Switched to dehydrator in current decade. I have a low budget dehyde. I leave the top off and have monitored highest temp to be 103-105. I usually think 30 min to be long enough but as I am near 70 and occasionally have a memory wrinkle have I have left a can or two in l-o-n-g-e-r than that.

[Art Anderson]

  On 10/28/2013 at 3:37 PM, hooknladderno1 said:

Spray cans are metal. Spray cans contain compressed flamable gases. The benefit of smoother flowinng paint can be accomplished by a much safer means while not sacrificing serious injury, death, fire, or explosion. That about sums it up... : )

Ditto!

Non-flammable propellants went away YEARS ago due to their environmental concerns, so guess what replaced those FREON propellants? Try propane and butane! Ask yourself: Would you heat up a propane tank or a butane lighter for any reason?

'Nuff said.

Art

[Pete J.]

Art,

Good point but again, I will refer you to the web site I mentioned in my earlier, post. Most of the stuff that we use is lacquer paint. By itself it is flammable. Just spraying it creates a hazardous situation both from in inhalation and fire stand point. What has been argued here is having a can explode. The expert data seems to indicate that exploding cans are highly unlikely. The internal temperature has to get to about 190 degrees for the can to deform and much higher to fail. Since all the food dehydrators I have researched are not capable of producing a temperature of more that 120 degrees even if everything inside fails, I am quite comfortable heating them in this fashion. In fact this is a temperature that would be within a few degrees of putting the can in a sunny window on a hot day.

The main failure and most dangerous failure seems to be dropping the can on a sharp object such as a corner of piece of angle iron or other similar object and you have an uncontrolled release of the contents along with some nearby ignition source. Short of doing something really stupid like putting it on a stove top or near a fire, failure of this type is quite unlikely. Judging from the fact the aerosol cans are still around in abundance, would indicate to me that the number of injuries that occur are very low or they would be gone as a result of litigation. No, you don't want to throw one in a fire or heat it in an uncontrolled fashion, but a little common sense is all that is needed to have a safe situation. I like my chances with a very limited heat source like a food dehydrator. The use of hot water is in my mind potentially more hazardous as most people are not real good at judging temperature and the boiling point of water(@sea level) is at or above the failure point of the can. Even then, the cans do not fail buy bursting. The failure is progressive and only becomes explosive when a ignition source is provided.

Again, I restate that common sense is needed to use a tool correctly. Heating a can in a controlled environment, free of ignition sources can be safe. I would be more concerned about using rattle cans for the purpose intended but in any enclosed environment with any ignition source(in a garage or basement in the presents of a water heater comes to mind) is far more likely and dangerous than simply heating the can.

Edited October 28, 2013 by Pete J.

[scalenut]

* removed bad video

Edited November 1, 2013 by scalenut

[High octane]

I used to spray paint over a cloth and newspaper on top of the washer & dryer, and the furnace and hot water heater were also in the laundry room. NOT any more!

[dustym]

Since I use my airbrush, I decant it to my bottle and then put it in the dehydrator.

[martinfan5]

  On 10/28/2013 at 10:01 PM, Pete J. said:

Art,

Good point but again, I will refer you to the web site I mentioned in my earlier, post. Most of the stuff that we use is lacquer paint. By itself it is flammable. Just spraying it creates a hazardous situation both from in inhalation and fire stand point. What has been argued here is having a can explode. The expert data seems to indicate that exploding cans are highly unlikely. The internal temperature has to get to about 190 degrees for the can to deform and much higher to fail. Since all the food dehydrators I have researched are not capable of producing a temperature of more that 120 degrees even if everything inside fails, I am quite comfortable heating them in this fashion. In fact this is a temperature that would be within a few degrees of putting the can in a sunny window on a hot day.

The main failure and most dangerous failure seems to be dropping the can on a sharp object such as a corner of piece of angle iron or other similar object and you have an uncontrolled release of the contents along with some nearby ignition source. Short of doing something really stupid like putting it on a stove top or near a fire, failure of this type is quite unlikely. Judging from the fact the aerosol cans are still around in abundance, would indicate to me that the number of injuries that occur are very low or they would be gone as a result of litigation. No, you don't want to throw one in a fire or heat it in an uncontrolled fashion, but a little common sense is all that is needed to have a safe situation. I like my chances with a very limited heat source like a food dehydrator. The use of hot water is in my mind potentially more hazardous as most people are not real good at judging temperature and the boiling point of water(@sea level) is at or above the failure point of the can. Even then, the cans do not fail buy bursting. The failure is progressive and only becomes explosive when a ignition source is provided.

Again, I restate that common sense is needed to use a tool correctly. Heating a can in a controlled environment, free of ignition sources can be safe. I would be more concerned about using rattle cans for the purpose intended but in any enclosed environment with any ignition source(in a garage or basement in the presents of a water heater comes to mind) is far more likely and dangerous than simply heating the can.

I store all my rattle cans in my garage, I live in Phoenix, this summer, I think the hottest day was 118, so its safe to say that the inside of garage was well into the 100's , on the upside, the cans are ready to go when I am ready to paint

[ERIK88]

Wow uve been lucky none have exploded martinifan5

[Ace-Garageguy]

  On 10/28/2013 at 3:44 AM, High octane said:

I put some hot tap water into a pot and put the can in the water for 6 or 7 minutes and then spray paint. It seems to work good as I've been doin' it for years and the paint flows smoothly.

Yup...and I just run some hot water in the sink with the stopper closed. Simple, quick, works every time. Water transmits heat to the paint faster than air will, and the heavy part of the can (the paint) ALWAYS is down in the water.

[ZTony8]

Best method I've found is to obtain one of those mug/candle warmers from a craft store(like Michael's).It's cheap-about $5 with a discount coupon.The can seems to retain it's heat longer this way versus dunking it in water.I've inadvertently left a can on the warmer until it was uncomfortable to hold and it didn't burst so it's reasonably safe to use.

[Casey]

Here are the labels from three different cans of spray paint-- Tamiya Fine White Primer, Testor's One Coat Lacquer, and Duplicolor High build grey primer:

120* F seems to be the agreed upon maximum temperature the can and/or it's contents should reach before it becomes unsafe, so stay under that temperature and you should be fine. Now, there are different ways to warm a spray, and the Tamiya can specifically states "Do not expose to heat...", the Testors can says "Keep from heat and flame", and the Duplicolor can reads "keep away from heat, sparks, and open flame," so if you choose to warm the can, don't use an open flame and ensure you can keep it under 120*F, regardless if that heat source is a candle warmer, hot tap water, or a food dehydrator.