Roof rack hole solution?

[Tbkw01]

I have seen a lot of treads leaning either to inserting bolts with some sort sealant washer, welding the holes shut, or some sort of metal set/ bindo filler solution. I work in aviation and I have done plenty if bonding repairs on metal. It involves bonding a similar metal ( 4130 steel or 301 half hard) \slightly larger than the damaged area with a sealing chemical (mil-p-8802 or substitute). Has anyone tried anything similar in the past and what did they used to bond both metals? I am not crazy about a welder burning my headliner and I am not crazy about the bolt look. A flat oval patch painted to a close match IMO might look better.

 

[Kernal]

Can you educate us on chemically bonding metals? IDK

 

[RolandFJ40]

I just started mine tonight, pulled the rack and wind deflector off. If you haven't pulled the deflector off I would soon. The design flaw is they hid the bottom screw inside the bracket, which fills with water and never dries (pics will show this). I took my angle die grinder and knocked them down flush. I'll be filling the area with fiberglass reinforced filler then I'll paint. I could weld the holes but then I'd need to remove the headliner.

 

[breathed]

I too would be interested in learning more about a chemically bonded metal patch.

 

[plutonius]

Socket set screws with a dab of Permatex will at least sit flush or shy of the nutsert lip. That's what I used, although I also lined over it all.

 

[Flank]

My solution is not permanent, but I did clear silicon in the hole, followed by stainless hex screw and a nylon washer. Makes it water proof for now.

 

[Tbkw01]

Hopefully these images show up. One of the images shows a standard honeycomb repair done in aviation. All if want to borrow is one of the layers (metal) and "paste" it on with adhesive, more permanent than silicone. The second picture (blue paint) is composite patch but I wanted you to get an idea of how flush it could be. The metal could be cut 1/2 -1 inch larger than the area that is damaged. I just need to find a good adhesive available to everyone. I am sure that someone has done something similar at least once.

 

[Tbkw01]

Socket set screws with a dab of Permatex will at least sit flush or shy of the nutsert lip. That's what I used, although I also lined over it all.

eventually I want to Monstaliner my vehicle, but in the meantime I want to start working on the rack area.

 

[musthave]

I'm not familiar with bonding metal to metal other than welding. I like the sounds of this adhesive / bonding agent, would really like to know more about it. I'm sure everyone would.

 

[Tbkw01]

I just started mine tonight, pulled the rack and wind deflector off. If you haven't pulled the deflector off I would soon. The design flaw is they hid the bottom screw inside the bracket, which fills with water and never dries (pics will show this). I took my angle die grinder and knocked them down flush. I'll be filling the area with fiberglass reinforced filler then I'll paint. I could weld the holes but then I'd need to remove the headliner.

yeah, I thought about fiberglass too but I live in south Texas and our sun is pretty brutal. I don't know how long a one sided (I don't want to mess with the headliner either) fiberglass cloth repair will hold up in our heat.

 

[Bastler]

Mil-p-8802 is a standard which applies to polysulfide based adhesives, which are particularly desirable for chemical and extreme moisture (i.e., submersion) resistance - not properties which are particularly important in this application, unless you regularly do water crossings up to the roof...

Pretty much any epoxy will bond extremely well to metals, the key is always surface preparation. Make sure that both surfaces are clean - typically denatured alcohol or acetone work well. You can bond to the painted surface without having to sand it down to the metal (after all, the paint and the epoxy are both just polymers with good adhesion qualities) but it is probably a good idea to scuff the paint with sandpaper to roughen it up, as that will give the epoxy a better surface to stick to. (The exact same idea as scuffing your paint before applying bedliner.) If you really want to get crazy, you could get some chromic acid and etch the metal surface, but the hazardous waste is probably not worth it...

I'm sure I'll take some heat for this, but I am something of a fan of JB Weld. I've messed with a ton of epoxies (I work in a composites lab) and JB actually has a pretty impressive combination of adhesion, strength and flexibility. If you don't like JB, your local hardware store will have epoxies in a variety of viscosities and cure times. Make sure you get something with a long enough working time to get the job done, and thick enough viscosity to not run all over, or let your patch slip out of place before it starts to set up.

If you decide to try a fiberglass patch, talk to a local who does boat repair and ask what epoxy/polyester resins they have had good luck with. Also, get some black dye to add to the resin, as that will significantly improve it's UV degradation.

Good luck.

 

[coues7]

Great info.

 

[cartercd]

If you have 3rd row speakers, you can remove the plastic covers and get access to the roof rack holes. This opens up the possibility of adhering metal to the underside of the hole. You could JB Weld a quarter there and it would would probably last a lifetime.

The front holes are more of a challenge, but there is a path via the moonroof. You could perhaps fish some wire through the roof hole, along the moonroof, and through the center of a quarter (or other metal piece). Then pull the wire so the quarter is pulled tight against the underside of the hole. You would have to get some adhesive in there at some point.

This would really be bonding the metal patch panel to the paint on the underside of the roof, but if you can get the surfaces clean it should work.

 

[cruiserdan]

I just started mine tonight, pulled the rack and wind deflector off. If you haven't pulled the deflector off I would soon. The design flaw is they hid the bottom screw inside the bracket, which fills with water and never dries (pics will show this). I took my angle die grinder and knocked them down flush. I'll be filling the area with fiberglass reinforced filler then I'll paint. I could weld the holes but then I'd need to remove the headliner.

The US market accessory roof racks and rear wind deflectors are two examples of products designed to look good and create additional profit. There was no long term study of the downstream implications that the installaton of those add-ons created.

Toyota is not the only manufacturer that has offered stuff that requires you poke holes in a perfecly good vehicle so you can't blame only them.


It does not require a brain surgeon or a rocket scientist to tell you that when you disrupt a factory painted/sealed surface you risk down-stream rust issues. Couple that with multi-layered components with the ability to collect moisture and rust is only a heartbeat away.

 

[artech]

Ever tried 3M 5200 epoxy as a bonding agent? We use it on boats only when you never, ever, ever want to take something apart ever again. So strong it will actually delaminate epoxy resin fiberglass instead of letting go, but I have never used it on sheet metal. Available at many boat shops or online at Hamilton Marine or other websites.

I used West Systems 610 thickened epoxy('cause I had some already) on my rusted 95 roof rack patches and it seems to be holding well, but 5200 is even stronger.

Hope this helps!

 

[Bastler]

Ever tried 3M 5200 epoxy as a bonding agent? We use it on boats only when you never, ever, ever want to take something apart ever again.

3m 5200 is a polyurethane, actually. It should work well on metals, but an etching primer might make it even better. Realistically, there shouldn't be much stress on this patch, and the extra elasticity of a polyurethane should address any stress from body flex.

Polyurethanes are probably the only family of adhesives that I would say are more versatile, and more tenacious, than epoxies. There is some other exotic stuff out there, but not readily available to the general public.

We once mixed up some polyurea at the lab to fix a fiberglass water cooling tower - mixed it, poured it on the cracked fiberglass, it was cured in about 30 seconds, and has been in use for two years so far without issue. Awesome stuff.

 

[bowtiestang]

Toyota is not the only manufacturer that has offered stuff that requires you poke holes in a perfecly good vehicle so you can't blame only them.
.

Yes I can!

 

[artech]

I learn something new here every day! Thanks!

 

[dgerst]

I'm thinking about building a low profile roof rack using short Bulldog gutter clamps. This would require removal of my factory rack. Judging from the experiences mentioned here, it's gonna be hard for me to get the nerve to unscrew that rack from my otherwise decent factory paint. I'm worried what I might find. I have use 3M 5200 before and can attest to its abilities. Pretty amazing stuff.

 

[western flyer]

dgert: Get up the nerve. Suggestion -- liberally spray the hardware with some PB Blaster or equivalent a week ahead of time. Then go ahead and try to unscrew your roof rack hardware (and wind deflector, if you have one). If the nutserts spin, you will know pretty fast. If they spin you can then tighten the rack back down and re-think how to go after the spinning nutserts. Search here on mud...
https://forum.ih8mud.com/80-series-tech/80-series-te...e-removal.html

https://forum.ih8mud.com/80-series-tech/80-series-te...k-removal.html

https://forum.ih8mud.com/80-series-tech/80-series-te...ack-patch.html

https://forum.ih8mud.com/80-series-tech/80-series-te...ce-needed.html

https://forum.ih8mud.com/80-series-tech/80-series-te...s-removal.html

https://forum.ih8mud.com/80-series-tech/80-series-te...roof-rack.html

https://forum.ih8mud.com/80-series-tech/80-series-te...ervations.html

If the nutserts do not spin the rack will likely come off easily; you will then see the potential mess. You can then use an appropriate sealer on the old or some new stainless hardware (IIRC they are M5 x 0.8 mm screws) to quickly seal up the nutsert holes for the interim period until you decide how to attack whatever you find for the long-term. Here is what I did long-term for the deflector:

https://forum.ih8mud.com/80-series-tech/597910-wind-deflector-woes-2.html

I think I have a tube of 3M 3200 that I have never tried (from West Marine). I will have to give it a go on some future project.

Cheers, Jon