MaxAir fan problem

[Kahoona]

I have a five year old MaxAir Vent fan. It has worked OK up until this year when it started to hang up on opening. The lid seemed to have warped and I either had to lubricate the inside of the lid periodically or help it to open using the knob. Two years ago I found a crack at the hinge in the rear and now I have found another and a much bigger one on the front. A piece fell off while I was examining it.



It has deteriorated due to UV. Just in case you run into this problem I do have a plan. I sanded the surface and cleaned it with alcohol. I taped it together and epoxied the cracks that weren't under the tape. Tomorrow I will epoxy the rest of the cracks. I will spray paint the entire lid with some good outdoor enamel paint. The major paint makers all use plenty of UV protection because their reputation depends on performance.I think that the plastic makers leave out the UV protection because these things will be out of warranty or not covered anyway. The paint doubles the life and will save a half gone piece. It is getting to the point where some people I know of automatically paint their new plastic before installing it. I'll send more pics as I go.

[EngineerMike]

IIWMI'd use FlexSet epoxy by Marinetex (amazon). It'll stick to anything. I'd use a thin piece of plastic like off a flat-ish blister pack for a reinforcing at the big crack. Then paint as you suggest.

The FlexSet will repair a poly tank, which is tough for most glues.

[Kahoona]

In this pic I have repaired it. I thank those who have suggested their favorite bonding agents but I already have Epoxy resin and a variety of modifiers that I have used in boat repair so I used an epoxy mixed with a bonding and thickening agent. Regular Epoxy does not stick to this plastic even when sanded lightly and cleaned with solvent. Coarse sanding was needed along with the bonding agent. I have re-coated the roof since so I won't be able to get to it far 3-4 days. I plan to check for adhesion and probably sand and add fiberglass mat to the repaired area and add another coat of epoxy with bonding filler this time. Then probably sand smooth before painting. It is way too much work but I don't want to have to replace the vent fan soon. Then I will paint with a good thickness of Rustoleum gloss white. Light will still come through the paint so it will still provide some lighting. I have already painted the bathroom skylight to reduce the ferocious heat that comes through in the summer. It reduces the heat and glare but still lets enough light through.



More pics to follow.

[Kahoona]

I am getting tired of being up on that roof so I just gave it two coats ob paint without making it flat. I did rough up the entire lid with 220 grit first. I also painted the exposed parts of the base.