SikaFlex and VHB Tape strength?

[dgorila1]

I know that there are many adhesives (liquid and tape) on the market today that are as strong or stronger than welds. Many metal parts of cars today are bonded together instead of using welds like older vehicles.
My question is: has anyone used a bonding compound like SikaFlex or VHB Very High Bond) Tape to attach racks to the roof of a vehicle? I'm sure there are ones made to hold anything on a roof without fear of the rack ripping off from the wind of driving, rain and sun exposure. Anyone have first hand experience? Thanks.

[o1marc]

I ordered and have some 3M VHB, but I could only find it in 2" squares and nothing bigger. Was going to use it it on 'some' of my solar rack brackets. to avoid drilling as many holes in the roof as possible.

[dgorila1]

Originally Posted by o1marc

I ordered and have some 3M VHB, but I could only find it in 2" squares and nothing bigger. Was going to use it it on 'some' of my solar rack brackets. to avoid drilling as many holes in the roof as possible.

Search "VHB Tape" at McMaster Carr www.Mcmaster.com or MSC www.MSCDirect.com . It comes in rolls, squares and other forms. I use it at work for attaching label plates to machinery. I'm just wondering what will work best for a roof rack that sees hurricane force winds on every drive as well as the elements.

[o1marc]

Originally Posted by dgorila1

Search "VHB Tape" at McMaster Carr www.Mcmaster.com or MSC www.MSCDirect.com . It comes in rolls, squares and other forms. I use it at work for attaching label plates to machinery. I'm just wondering what will work best for a roof rack that sees hurricane force winds on every drive as well as the elements.

Do you have any data that shows they take hurricane force wind? How much actual wind speed is there 6" off the roof at 60mph? I tried to get the shear strength from 3M, they had no idea..
I just bought a fish scale to see how heavy the solar panels would be to lift, I can do a test on one of these 2"x2" pieces. hang a bucket and start filling it with water till it fails.

[o1marc]

Here's the closest I could come to a bus wind tunnel test. I think my flat front bus would be similar and not have much air movement 6" off the roof.

[dgorila1]

Originally Posted by o1marc

Do you have any data that shows they take hurricane force wind? How much actual wind speed is there 6" off the roof at 60mph? I tried to get the shear strength from 3M, they had no idea..
I just bought a fish scale to see how heavy the solar panels would be to lift, I can do a test on one of these 2"x2" pieces. hang a bucket and start filling it with water till it fails.

Did a quick search of 3M's website and they have specification sheets for all the different products. I just picked the one for 3M VHB Commercial Vehicle Tape CV45F since it's probably ideal for most of our applications. Looks like they have pretty good data on shear strength, pull strength, etc.

[2kool4skool]

We have VHB holding the 2 solar panels on the roof of our bus. I cleaned/roughed up the white roof paint and each panel has 4 feet. I give them a pull now and then to see if they're holding.
Over 4 years so far.

[farok]

Originally Posted by 2kool4skool

We have VHB holding the 2 solar panels on the roof of our bus. I cleaned/roughed up the white roof paint and each panel has 4 feet. I give them a pull now and then to see if they're holding.
Over 4 years so far.

Are these flexible panels, I assume? If they're not flexible panels, I'd love to see how you did this!

Supposedly this stuff is strong enough to hold window skins in place, as well, though I've not personally tried this.

Chris

[dgorila1]

Originally Posted by farok

Are these flexible panels, I assume? If they're not flexible panels, I'd love to see how you did this!

Supposedly this stuff is strong enough to hold window skins in place, as well, though I've not personally tried this.

Chris

Looking at the 3M website, it's used to hold windows to the sides of skyscrapers.

[dgorila1]

Originally Posted by 2kool4skool

We have VHB holding the 2 solar panels on the roof of our bus. I cleaned/roughed up the white roof paint and each panel has 4 feet. I give them a pull now and then to see if they're holding.
Over 4 years so far.

I was wondering if just roughing up the paint is good enough prep or if you needed to go to bare metal. Guess this answers the question.

[2kool4skool]

Rigid panels Farok. Tape between each foot and the roof. You can't see it so a pic wouldn't show anything.

[o1marc]

Originally Posted by 2kool4skool

Rigid panels Farok. Tape between each foot and the roof. You can't see it so a pic wouldn't show anything.

So did you use only the VHB to secure those brackets, no hardware?