[Solved] Aluminum's ability to transfer heat w/ paint?

[NightExplorer96]

I received my Aluminum plate today but noticed it isn't very nice looking. Some sides have different colors, while others even have grooves in them.

That being said, I went ahead and bought some metallic paint to help make it look a little nicer and was told this might reduce aluminum's ability to take heat away from the laser, which would make sense to me as this is a barrier between the metal-metal connection. Thing is, I left one side without any paint. Should I paint that as well or leave it as is to allow the laser head to sit against the metal itself?

Thanks,
Alex

 

[gozert]

Re: Aluminum's ability to transfer heat w/ paint?

I don't think a layer of paint that thin would significantly affect the heat transfer on it. Also, can't you remove it with some kind of paint stripper if needed?

 

[NightExplorer96]

I don't think a layer of paint that thin would significantly affect the heat transfer on it. Also, can't you remove it with some kind of paint stripper if needed?

Thanks for the answer gozert!

I can if need be, but I read online removing paint as such can release some lead or other dangerous toxins into the air. I also never knew you had to be 18 to buy aerosol paint

Edit: A laser would also never get hot enough to light the paint on fire, correct? The can says to not exposure to temps. over 110 Fareinheit or 48 Celsius!

-Alex

 

[Gabe]

Re: Aluminum's ability to transfer heat w/ paint?

If your laser gets that hot, the paint won't be your biggest worry
Why not grab a sanding block or sandpaper and sand away the grime/blemishes? I always loved the look of sanded metal, if you want it to look super neat you can sand in just one direction, or if you wanna be super fancy you can burnish the surface, look it up as its kinda tough to explain.

 

[NightExplorer96]

If your laser gets that hot, the paint won't be your biggest worry
Why not grab a sanding block or sandpaper and sand away the grime/blemishes? I always loved the look of sanded metal, if you want it to look super neat you can sand in just one direction, or if you wanna be super fancy you can burnish the surface, look it up as its kinda tough to explain.

Haha! But it should still work fine as a heat barrier right?

-Alex

 

[Pi R Squared]

Re: Aluminum's ability to transfer heat w/ paint?

I read online removing paint as such can release some lead or other dangerous toxins into the air. I also never knew you had to be 18 to buy aerosol paint

That law was enacted many years ago to help reduce graffiti. It didn't work, only law abiding people under the age of 18 who wouldn't ever use it for graffiti care about the law, the criminals will still get their hands on cans of spray paint.

Maybe you could put the laser head on the plate and draw around it and paint only outside the lines.

Alan

 

[NightExplorer96]

That law was enacted many years ago to help reduce graffiti. It didn't work, only law abiding people under the age of 18 who wouldn't ever use it for graffiti care about the law, the criminals will still get their hands on cans of spray paint.

Maybe you could put the laser head on the plate and draw around it and paint only outside the lines.

Alan

Thanks for the input Alan!

I decided to paint all of it as it would look much nicer that way. Hopefully it works well!

-Alex

 

[Laser Chick]

Re: Aluminum's ability to transfer heat w/ paint?

The can says to not expose to temps. over 110° Fahrenheit or 48° Celsius because the can might explode. Also when the paint is still wet or a liquid it is very flammable.
Once the paint is cured/dry it can be exposed to temperatures much higher than that.

 

[Teej]

Re: Aluminum's ability to transfer heat w/ paint?

The heat sink needs, ideally, to be paint free, and as smooth as possible to maximize conduction.

The more contact surface area, the better the conduction.

Two smooth surfaces will have more contact than painted, or rough surfaces, etc.

 

[NightExplorer96]

Re: Aluminum's ability to transfer heat w/ paint?

^Thanks to both of you guys!

@Teej Exactly the answer I was looking for. Fortunately, most lab lasers already do a pretty good job of maintaining heat levels low and the plate will be an extra layer of protection. At least, much better then running on wood

-Alex

 

[Dr_Evil]

Re: Aluminum's ability to transfer heat w/ paint?

yes, paint will slow down heat transfer. It's worse than thermal compound. Ideally two perfectly smooth metallic surfaces would do the best at heat transfer. That's in a perfect world though. If you want to separate the two devices easily, two smooth surfaces with a small amount of thermal compound the best method.

That law was enacted many years ago to help reduce graffiti. It didn't work, only law abiding people under the age of 18 who wouldn't ever use it for graffiti care about the law, the criminals will still get their hands on cans of spray paint.

Maybe you could put the laser head on the plate and draw around it and paint only outside the lines.

Alan

Don't forget about using paint as an inhalant.

 

[NightExplorer96]

Re: Aluminum's ability to transfer heat w/ paint?

Got it Dr. Evil!

Still, a thin layer of paint should still allow the Labby to transfer heat onto the Aluminum correct?

-Alex

 

[Teej]

Re: Aluminum's ability to transfer heat w/ paint?

Got it Dr. Evil!

Still, a thin layer of paint should still allow the Labby to transfer heat onto the Aluminum correct?

-Alex

Sure, think of it like this:

You can make paint hot. When the paint is hot, it will make the metal its painted onto, hot too.

It just won't transfer that heat as quickly, as it acts as an insulator, albeit with a small R value.

 

[Blackwolf]

Re: Aluminum's ability to transfer heat w/ paint?

it is Al have it anodized or mirror polish it (400grit -> 800 -> 1500 -> buff with white compound -> buff with red or blue compound)

 

[Pi R Squared]

Re: Aluminum's ability to transfer heat w/ paint?

Don't forget about using paint as an inhalant.

Oh yes I forgot about that, but I didn't know anyone used spray paint for that, I thought it was only canned paint, polyurethane or some such thing. I would think it would be very unsafe to inhale any type of spray paint.

Alex one thing you could do that would be easy, before you spray paint the plate, cover one side with masking tape, put the laser head on it and cut around it with an X-acto knife or razor blade and peel off the excess tape and then spray paint it, and after it dries then remove the tape and you have an unpainted area just the right size.

Alan

 

[Alaskan]

Re: Aluminum's ability to transfer heat w/ paint?

I vote no paint, it will insulate the aluminum from optimum heat transfer.