100W bulb for curing conformal coating

[dknguyen]

I need a makeshift non-critical way to cure some silicone conformal coating. I haven't modified an oven yet or anything so it can stay as low as 65C. But I was thinking about a quick and dirty way by leaving it really close to a 100W light bulb for a while.

Anyone have any idea to the air temperature 1cm from a 100W light bulb? Or whether this will help at all? It will cure at room temperature, but I don't want to wait 48 hours. At 65C it takes about an hour.

I can't seem to find a thermometer lol.

 

[Pommie]

I don't know the temperature near a light bulb but can think of a few other ways to get a warm place. Our oven has a plate warming setting which is 75°C or how about a hot water bottle with a cake rack over it and a washing up bowl inverted over the whole lot so as to keep the heat in. You could replace the hot water bottle with a lump of metal (IE griddle plate) heated in the oven. What about near your hot water tank, near your car radiator, under a black bucket left in the sun.

Mike.

 

[Someone Electro]

Just put it on top of a CRT monitor that was left on for some time.

 

[Death By Bass]

Silicon conformal coating (atleast the stuff we use at work) doesn't need to be cured, it will just dry over a few hours, and be no different to that, or being put in an oven for half an hour...

 

[Hero999]

Have you tried using a hair dryer?

 

[dknguyen]

I don't feel comfortable with leaving a hair dryer on uattended for an hour.

It will cure on its own a 25C but around here it is already colder than that (and still getting colder) and with a 48 hour cure time, that's just too long since i have to do a few boards and multiple sides. The manufacturer also says the coating is mechanically stronger if cured under heat.

 

[HiTech]

a small electric space heater set on LOW?

 

[poopeater]

Have you tried setting it on fire?

 

[Death By Bass]

wouldn't you normally have a heater on wherever you're working anyway?

we do all our conformal coating "out the back" even when its 12degrees cold, and 80% humidity...

they dont come up too well then... lol

oh!!! but if you warm the boards up first, they will turn out alot better!!!! even if they are only like 22 degrees or whatever (the AC in our workplace is always set around here)

 

[Hero999]

12 degrees C or F?

Some conformal coatings will cure at 12 degres C but it takes a long time but forget about it at 12 degrees F

 

[zevon8]

We made something like this for the shop, it is used to cure a urethane potting compound. We did it with one of those cheap utility closets with the particle board shelves. It is about 6 foot tall, 30 inch wide, 18" deep. We put a single panel with light bulbs mounted on the bottom. In the solid shelves we made a bunch of 2" holes on one end, and matching 2" holes on the opposite side of the cabinet beside the lamps. Repeat this up to the top, alternating the end with the holes, so the air flow zig zags. At the top of the cabinet there are three 5" muffin fans that pull air through the cabinet, heated by the lamps. It gets about 30 C inside, curing the urethane in about 2 hours. We have nine 60 watt bulbs, we unscrew some for less heat. we use it to dry alot of stuff.

If you made a smaller box an put a fan in it, and one bulb, it would probably work also. try different wattages till you get the temperature you need.

edit -- some embarassing spelling

 

[RODALCO]

Use the electric oven on low with the door open, ave temp is around the 65°C 70°C mark.