1st repair on new to me RV complete

[Forkyfork]

Originally Posted by Monster1

I contacted icom who is the manufacturer of the skylight. They stated that they recommend their skylight sealant for the skylight application. I informed them of my situation directly asking if the dicor would chemically damage the skylight over time. They replied back and said dicor would possibly be too "stiff" and not expand/contract with the skylight and roof properly in heat cycling. Honestly, this whole thing about chemical degradation sounds like made up internet discussion that has been parroted and carried over to different forums.

Interesting. Well, the self leveling Dicor I don't think will be too stiff.

I certainly am never using ProFlex again. Well at least it was super easy to remove and left no residue. Do you remember as a kid playing with Elmers glue in the pencil trough of your desk or wherever you happened to smear it on and then peel it off with that cool skin. Proflex is exactly like that. With the same stiffness and dryness and lack of adhesion.

Im going to order some of that SB-140 and play with that and see how it is before actually sealing anything with it.

[Roadrunner]

Most skylights are made of acrylic. There are two possible reasons for cracking..... First, petroleum based products are not compatible with acrylic and if there are any residual petroleum distillates that remain in the product after it cures, it will cause cracking or crazing of the acrylic to the point it will become brittle over time.

Second reason is screws are being over tightened when skylight flange is screwed to the deck. After a bead of sealant is laid and the skylight is positioned, the screws should only be tightened enough to cause the sealant to run out along edge and the acrylic begins to slightly dimple. Over tightening the fasteners can result in cracks radiating from the screw holes.

Compatible sealants will typically have a chemical such as naptha that will off-gas quickly before it completely cures. Thus, not leaving any residual in the cured product. Sure Bond SB-140 is recommended by many skylight manufacturers.

[Tha_Rooster]

Funny it doesn’t say plastic.

[Forkyfork]

Originally Posted by Tha_Rooster

Funny it doesn’t say plastic.Attachment 222453

It says air vents. I haven’t seen a metal air vent since the 70’s.

[Tha_Rooster]

Originally Posted by Forkyfork

It says air vents. I haven’t seen a metal air vent since the 70’s.

The frame that screws and gets sealed to roof is metal only lid is plastic!

[Monster1]

Originally Posted by Tha_Rooster

The frame that screws and gets sealed to roof is metal only lid is plastic!

He's correct partially. Back when in our family owned rv dealership days where I was working in the parts department, all the vent assemblies were plastic based. Customers used to pull their hair out because they would only last a few years in our hot California sun before the entire thing would have to be changed out. We couldn't keep vents and putty tape in stock. I remembered some of the older units like Aristocrat and Kenskil at the time were metal frames and lids. They lasted forever. But the newer stuff was plastic. When I climbed on top of my 2006 trailer recently, I noticed the bases were metal and the lids were still plastic. Glad to see they still make some of these parts in metal. The sun is just to brutal to have to change all this stuff out every few years.

[Forkyfork]

The fan-tastic fan mounting flange is plastic. Im pretty sure everything on my roof is plastic. Not 100% sure

[Mr_D]

Newmar warns against using Dicor on the domes. It was in the owners manual for our '02 DSDP.