Dry spray paint in 20 minutes.

[mr_modify1]

Great for smaller pieces of metal.

[nova_robotics]

I hate to be that guy, but I hear this repeated on jobsites all the time. The moisture isn't coming out of the metal. Craft guys will swear up and down there's water in steel, and that a torch makes it come out. There is no water in steel.

I have a cheapo digital heat gun. You can just set the temperature on a little LCD display on the back. It's pretty handy. I've used it to cure JB Weld and paint super fast many times. I'm sure the NACE inspector would have something to say about it though.

[Beserkleyboy]

Yup...I think he was absent that day when the physics class studied humidity and condensation...and EVERY tin of paint, anywhere in the world has min & max temps specified, based on not just ambient temperature, but accepting that the substrate to be painted is at equilibrium with the ambient temp...good thing he's probably not guaranteeing his hobby work...

[sossol]

I hate to be that guy, but I hear this repeated on jobsites all the time. The moisture isn't coming out of the metal. Craft guys will swear up and down there's water in steel, and that a torch makes it come out. There is no water in steel.

I have a cheapo digital heat gun. You can just set the temperature on a little LCD display on the back. It's pretty handy. I've used it to cure JB Weld and paint super fast many times. I'm sure the NACE inspector would have something to say about it though.

This is the first I've heard the notion that water is *in* the metal. Maybe he meant on, but misspoke.

I'll admit that it's pedantic, but my pet peeve is usage of the term "drying". Except water-based paints (tempura, gauche, etc.), paint doesn't dry - it cures. In most cases heat accelerates the chemical process.

A quartz heat lamp would give the same results as far as a faster curing time after painting, but I've used this pre-heat trick. It does work. Letting parts sit on a heater that's in use anyhow works a treat.


Neil

[NortonDommi]

"Letting parts sit on a heater that's in use anyhow works a treat." bought back a memory of last century when a place I worked at had an old bar heater used to warm bits up before application of high heat wrinkle paint,(great stuff to cover up after fabrication without a lot of finishing work), and we used to heat the bits, remove the rack and apply paint from an aerosol can. We did this in the store room.
One day apprentice decided to much hassle to move the rack so started spraying while the heater was on. Flames made him drop the can into the heater.
The fire was put out but he had a LOT of cleaning up to do.

[Frank S]

"Letting parts sit on a heater that's in use anyhow works a treat." bought back a memory of last century when a place I worked at had an old bar heater used to warm bits up before application of high heat wrinkle paint,(great stuff to cover up after fabrication without a lot of finishing work), and we used to heat the bits, remove the rack and apply paint from an aerosol can. We did this in the store room.
One day apprentice decided to much hassle to move the rack so started spraying while the heater was on. Flames made him drop the can into the heater.
The fire was put out but he had a LOT of cleaning up to do.

Sounds like the apprentice was not ready for unsupervised work.

[nova_robotics]

This is the first I've heard the notion that water is *in* the metal. Maybe he meant on, but misspoke.

It's a very common myth all across Canada and the US with tradesmen. They call it "sweating out" the steel. They will swear up and down that there's water in steel, and that a torch makes the water come out. I've gotten into a number of arguments about this.

Also extremely common:

Gasses don't weigh anything. For example, a full bottle of argon will weigh the same as an empty one.

If you put an extension on a socket it will somehow make the torque "go away," and you need to increase the setting on your torque wrench. This one really gets me because guys overtorque bolts ALL THE TIME, sometimes to the point of snapping the heads off because the torque "disappears" inside the extension for some reason. If a bolt needs 100 lbs-ft of torque, you can be guaranteed that the tradesmen will tack on at least another 25-30 lbs-ft if they're using an extension. This isn't just common it's basically a rule among the trades. Drives me nuts.

[sossol]

It's a very common myth all across Canada and the US with tradesmen. They call it "sweating out" the steel. They will swear up and down that there's water in steel, and that a torch makes the water come out. I've gotten into a number of arguments about this.

I'd always assumed that sweating the steel was rhetorical, since it resembles sweat.


Neil

[Rangi]

Are you using the term "trades" loosely.

[mr_modify1]

Yes you are correct it only looks like it is coming out of the metal but really is condensation. If the metal were damp it would be dry after the heating. Regardless of any water coming from anywhere this process really works to give you a dry paint in about 20 minutes.