Hot Rods Infrared Heat versus Curing Lamps

Is there a difference between infrared heat and infrared curing lamps? On another forum I was told the heat type won’t cure paint. How long should they be? I know the short wave are better but I don’t have that kind of money...


Here’s what I’m looking at and they are 16-17” wide.

 

I was called into work today as a bit of an emergency came up. I thought when I’d get home I could find all I needed to know on this subject! And what do I find? Nothing, zilch, nada, absolutely nothing (say it again).

Come on guys... spread your knowledge and educate me! I’m talking about you painter types and teachers...you know who you are!

 

I don’t know anything about the difference in the lamps you asked about, but.....heat cures paint. Plain and simple. That’s why paint booths have a heat cycle. It’s hot air and it speeds up the curing.

 

Calling @anthony myrick, @paintguru

 

Infrared heat is infrared heat . I've used heat !amps , on small projects they work well , it would take at least a 1/2 dozen to cure a fender . There may be some " wave length" thing , never was that interested ...

 

https://www.autobodytoolmart.com/paint_curing_lamps

I’m no scientist. but I read a lot of tech sheets. Most of em dont like temps below 60. ( US degrees)
I have a small IR lamp. I’m told these heat inside out. Who knows. It works well.
But any warmth can help when it’s cold.
The surface temp is as important as air temp.
The expensive commercial units are designed to speed up production. Or make ya $$$$$
They do.
For our home stuff, keeping the temp (surface and air) above/around 60 would be my concern
I like paint that dries slow anyway
I’d rather it be a little cool than stupid hot.
What’s the end goal you are looking for?

 

On cold days, I fire up the forced air torpedo heater. Warm up the shop and surface temps.
Shut it off while spraying color or clear.
Fire it back up after everything flashes.

 

https://www.google.com/shopping/pro...s=eto:9140196142450025686_0,cdl:1,prmr:1,cs:1
this is the small one we have at school

 

We used one like that when I managed a body shop. I was "told" that the heat waves heat from the metal up.

So in theory it warmed the metal which in turn cured the paint from the bottom up allowing the solvents to escape thru the top coats of paint allowing it to dry faster.

But who knows for sure!? In another 20 yrs we may find out it was just snake oil in order to charge us double the price of a regular infrared heater.

.

 

This is exactly what I have always done as well.

 

Size matters? The ones I have are about 17” long. And what kind of area would one lamp cover? Sorry for all the questions but I don’t want to leave my painting until late spring or summer. I do have a torpedo type heater that I could elevate the temp for a short period.

I have to admit something which is a wee bit embarr***ing... I have natural gas to my shop and have an IR heater hanging but I also have some very expensive wood flooring hanging as well which could get a little warm if heated too much and that might cause a big problem. So whenever I get that wood shifted I’ll heat up my IR heater and should be good to go.

 

I have floor embedded radiant heat in the shop, which is the same as infrared. It heats objects instead of air. The claim that it heats the metal which in turn cures the paint is stretching physics. Radiant/infrared heats both.

 

Torpedo heaters? Not kerosene I hope. No fisheyes with propane. When you exhaust you're ****ing out the heat so fast, something to be aware of. News flash; almost all heat is IR. Heat is in waves so how dense will or can you put those heat waves to work? Radiant heat a little 1st, and a little after. Too hot by just a smidge and it'll solvent pop, even if it flashes off 1st. In your zeal to get it done just keep in mind that paint fumes are EXPLOSIVE. Not trying to insult yours nor anyone else's intelligence. Friendly reminder. As said above consistent temps are worth pursuing.

 

I appreciate the comments of paint fumes I sure don’t want to make the 6:00 news! And yes infrared is heat. I suppose my main concern as I stated at the beginning that on another forum it was said that infrared heat and infrared curing lamps are different and I can’t get my head around that. I was just out in my shop with 8*C temp. I switched on the stand up unit I am testing and the panel got pretty warm in a hurry. However, the lamp is 17” long so the temp was localized. I’ve got a couple of units without the stand and I thought I could come up with a stand to mount them so I could have two or three aimed at the panel I want to paint. Heat up shop with my propane heater, turn it off, spray, and then turn on the infrared to help the paint cure. Any thoughts on this plan?

 

1,500W Quartz Ceiling-Mounted Heater with Light (princessauto.com)
I bought one of these from a neighbor who was moving. Rigged up an adjustable stand and used it like you described in your last post. Worked great. I painted some fenders and a hood on panel stands. I positioned the heater as low as possible pointed upwards, and put it under each panel in turn. Like you say, it heats things up in a hurry, so I just moved it around as needed.

 

Well you discovered my secret...bought the one with the stand about a month ago on sale and then I bought two identical wall mounts, one being cheaper than the other but different brands, at a “family and friends” event I’m pretty much good to go. Thank goodness for Princess Auto helping us hobbyists.

 

Logic would seem to dictate that "infrared heat" would be the stuff that comes out of an "infrared curing lamp", but terminalogical conventions can be wonky. It seems counterintuitive to call anything a lamp which doesn't glow visibly, so I'd expect that we're dealing with a broad IR spectrum, from long-wave IR, which is effective thermal radiation or radiant heat, through near IR, to visible light nearer the red end of the spectrum. If you can both see the glow and feel the heat, the frequency range is wide enough not to worry about frequency effects.

One thing to keep in mind, though, is that gl*** and other transparent materials tend to be transparent to visible light and shorter-wave IR but opaque to longer-wave IR. That is what allows a greenhouse to work. If you're painting, though, chances are that any gl*** would be removed or taped up anyway. In any event, you're still far away from far IR/microwave/radio frequencies, where liquids as such become opaque. (Sonar exists because water is opaque to the very long wavelengths typically used for radar.)

No, IR doesn't heat from the inside out. Nor does it heat the metal first. Radiant heat acts on the surface. It also travels in straight lines — because it is essentially the same sort of thing as visible light. For IR curing to be effective, the paint has to see the IR source. Anything which casts a shadow, including panel curvature etc., will undermine that. Ideally you want multiple IR sources, to get at the work from as many angles as possible. Think floodlights.

It's ambient heat (air-conducted/convective heat) that could, under the right cir***stances, heat the metal first. Relatively thick, heavy metal has a greater thermal capacity than a relatively thin layer of lightweight paint, so in a very hot environment like an oven it can allow the metal to act as a heat source to the back of the paint. What happens in practice in an IR curing situation is that radiant heat falls on stuff all over the room, heating it up and causing it to reradiate and raise the ambient temperature. That's still quite an inefficient oven.

BTW, curing and drying are two different things. Drying is evaporation of liquid solvents. Curing is a chemical reaction within the paint (or whatever) which causes it to turn into something hard, e.g. hydration of cements (which actually requires an abundant presence of the same water which is used as a solvent in pouring.)

 

Seeing the question originally I was curious and did some googling but with limited success, so didn't post, sorry!

RS components had some useful information but nothing that seemed to immediately help. Reading between the lines it appears to simply be a matter of scale, ie power. Last winter I was looking into buying one for painting use but what I was finding was they make reference to individual panels, leading me to believe they are suited to panel repairs, and not full paint jobs. I didn't bother and kept an eye on the weather forecast instead (uk weather is rarely very cold for any length of time) and all was thankfully good.

Multiple, small, cheap room heaters I'm sure are better than nothing but unlikely to provide the output (or consumption!) of a paint lamp.

So how do the guys who paint outdoor in a tarp shelter manage with snow on the ground? Or are their results poor?

Chris

 

The money they saved on building a garage, they spend on wet-n-dry.

 

A most definitely HAMB era infrared lamp. (Made June 1949).

It boasts many uses, some are in the garage:

Well, wouldn't you know it. Traditional to use heat lamps!

Phil

 

The few times I cured paint, I used the "floodlight" shape bulbs........ as Phil posted above.
Now that was a long while ago but it seems to me that the bulbs throw a bit more light than the "heater" matrix style which maybe is designed to throw a little more heat.
I currently don't have either to double-check but I think that when using the bulb type, if I put my hand between the lamp and the object's surface, I could see a more distinctive shadow than with the heater type.
But I'm no expert and don't actually know any facts.

I like the heater type when they are suspended overhead. Sort of feels like sunshine.
..

 

Curing. That chemical reaction from products with catalysts/hardeners doesn’t like cold
Drying doesn’t like cold either.
Both involve evaporation. The fumes being removed is important. Paint something in a booth, cut it off, shut the doors and see what happens.
Water based likes air flow.


I’ve never had a fish eye issue with the kerosene heater. But I rarely ever crank it up in Bama.

 

And for those that don't have a Princess Auto nearby, there's always Amazon!
Looks like the same unit Princess has, too.

https://www.amazon.com/Comfort-CZQT...t=&hvlocphy=1021852&hvtargid=pla-826932970029

 

Hey Ned Ludd, thanks for posting. I got all what you said and knew a lot of it already. When I see on the web that IR heats from the inside out I figure whoever wrote that is confused with microwave. I know that drying is distinct from curing in that drying, like laundry, needs solvents, water in the laundry example to escape and that curing needs the chemical reaction to take place like baking a cake. The drying out of the liquids in a cake via the oven heat is only step one, the curing of the ingredients (making new chemical bonds) produces something other than dried ingredients which we call cake.

Now I’m off to have a slice...

 

Seems like you got some feedback but this is exactly the kind of question I’d head over to the garagejournal.com one of Ryans other great forums

 

Hey forgot about Garage Journal! Thanks for the suggestion.

 

The most important thing is the wave length of the IR lamp there are long, medium and short. The shorter the wave length the deeper into the surface it will heat. You do not want long wave lamps as they will heat the surface only and cure the out layer of paint and could cause issues. Body shops for the most part use short wave and some medium. They are also the most expensive. I would guess anything you are buying from Amazon or Princess Auto are long wave.
www.vehicleservicepros.com/collision-repair/paint-and-refinish/article/21195052/short-wave-infrared-explained

 

K13, thanks so much for contributing as now I/we are getting somewhere! I knew about short and medium wave lengths but I should have realized there must be a long wavelength as well. And I get your point about different vendors...

So now I have to try and nail down the wave lengths of the IR units I’m looking at and possibly rethink this whole thing.

 

I wasn't knocking the vendors per say but bases on the prices of short wave length IR lamps, thousands of dollars, I would guess that ones that are under $100 are not going to have the same properties.

 

No I didn’t think you were knocking the vendors at all. I think you were being realistic in noting that the two that you mentioned would not be selling those specialized IR units that are available from auto body supply companies.

What do you think about rdscotty’s comment about heating a panel from the rear/underneath? You would get the heat to the panel and allow the paint to cue from the “inside out”...or not?