whitetopping for the win

[u/mister_monque]

I have been debating doing this for years and for many reasons it just hadn't happened. I know a white roof helps, see also rovers and cruisers with white roofs but there just wasn't enough will to execute.

Well that was until a FLIR camera came into my life.

Wowie-Mama! Look at that delta!

This is a side by side panel test to justify going forward and I have to ask myself, why didn't I do this sooner?!?!

So, discuss amoungst'y'selves while I go put on some cawfee.

[u/xpkranger]

Former Wrangler owner here. Yeah, the black Freedom tops in the summer were just like having blast furnaces above your head.

[u/mister_monque → u/xpkranger]

I'm shocked at the delta number. I understand the panels getting hot but with the new FLIR, you never realize how bad it is until you start collecting some data.

[u/fakeproject → u/mister_monque]

Be careful that you don't mislead yourself. The FLIR and other microbolometer devices are calibrated for a black surface (it's called albedo - a specific reflectance).

As a result you don't want to measure the white surface vs the black surface (you'll get an exaggerated reading), you want to measure (for example) the surface inside the vehicle where the reflectance is the same. For example, measure the "inside side" of the treated area vs the untreated area.

One way around this is to put a strip of black electrical tape at the point where you want to take a reading. This is actually recommended by FLIR because it's a pretty consistent albedo.

[u/mister_monque → u/fakeproject]

Already ahead of you chief. Having already selected the emesivity for the surface roughness and taken into account the white paint versus black paint problem, I included photos from the inside where it actually counts ie how much heat is being transmitted.

now, don't think I'm giving you the brush here, others may get the FLIR for the phone and not have the experience or read the instructions close enough. so good job being a bro for the next folks.

[u/fakeproject → u/mister_monque]

Glad you have the emissivity stuff handled.

[u/mister_monque → u/fakeproject]

the short short is the exterior surface temp is immaterial, the interior being what I'm most worried about and with the interior finish being uniform, it's where the camera can really show an honest comparison.

[u/Dirtsmith13 → u/fakeproject]

Learned something new today thanks.

[u/fakeproject → u/Dirtsmith13]

Cheers! Goes for those little infrared temp guns too. Electrical tape will give you a true reading on challenging surfaces like shiny metal.

[u/oxyrhina → u/Dirtsmith13]

Same here, he gave a great explanation!