Welding Tips and Tricks

I suppose that this 3M VHB tape has its usefulness,
but it's a very bold statement from 3M to say that it replaces rivets, bolts and welding.
http://solutions.3m.com/wps/portal/3M/e ... -VHB-Tape/
https://www.youtube.com/watch?v=7OtrDvDvF5I

Um.... WOW!!!

I'll have to get some and see if its what its cracked up to be....

Lets hear your review of it, Werkspace.

~John

John, I never heard of this tape until last year at the WMTS (Western Manufacturing Trade Show) in Edmonton, Alberta. I saw it at the 3M booth where they had a 10lb sledge hammer setup on a swing arm contraption. The idea was to lift up the 10lb hammer and let it fall on to two panels that were fastened together with the VHB tape. I tried it and it never failed.

I asked the rep, just how strong is this tape? and he replied that it would handle anything that I could throw at it. So, I got a couple of guys to hold the test stand from flipping over, and I let that 10lb sledge hit those two panels with all the force that I could throw at it. Everyone in the trade show heard that hammer hit those panels, but the tape did its job and the two panels stayed fastened together, aside from having a huge dent in both of them.

I've got some of this tape, but my only use for it so far, is to hold the side molding on my VW Jetta door.
https://www.youtube.com/watch?v=r_UOFUm8o3Q

AKweldshop wrote:Um.... WOW!!! I'll have to get some and see if its what its cracked up to be....Lets hear your review of it, Werkspace.~John

I still owe a buddy a buddy from the last prank he played on me. Might have to get some of this and
put it on his truck doors, then set back and watch him try and open them when it's quitting time.

https://www.youtube.com/watch?v=isF9Gk8iYq4

Here you go.... Fake!!!!!

I previously worked for a 3M Preferred converter for 17 years and have a lot of expierence with 3M VHB tapes. If the material is prepped properly it will hold as strong as a weld but take and absorb the shock load....it is amazing stuff.


A lot of trailers use tape instead of rivots on the skins and they last longer on the durability test, the roof in the MN airport also has a lot of vhb instead of welds and fasteners.

3M has a neat little gimick where they tape 2 pieces of alum beam together and tell you separate it. I was at a training seminar and although the beams bent I finally got it to separate, they wouldn't let me have it...lol

Properly prepped it is awesome stuff and used in many applications.

The trick with a lot of bonded joints to get them to separate is to start them peeling. That is usually their weakness.

Various epoxies these days are very, very strong (when the base materials are prepped properly.. this is crucial..) and for instance when used in aluminium constructions they allow for much smaller wall thickness parts to be used/joined as there is no HAZ that weakens the base material like welding does.

The weakness in these bonded joints lies in the peel-resistance..

They are virtually impossible to separate using shear or compressive/tensile forces as it simply tends to break the base material itself instead of the joint failing but start to peel a joint from one edge and you WILL break the joint.

That's why you usually see that bonded structural designs are set up differently from welded contructions as far as stress paths and load distribution go and sometimes 'peel arrestors' are added in the form of rivets that help to stop cracks and peeling. Aviation industry makes heavy use of these techniques in wing and fuselage design and also some higher end car manufacturers use bonded aluminium chassis parts.

Not saying that it's better than welding or not, but it's just a different method that has it's specific applications where it can be advantageous. Just like replacing metal with composites like kevlar or carbon fibre is sometimes an option, but also tends to require a completely different structural design to make use of the strengths of the material and avoid their inherent weaknesses.

Bye, Arno.