# How To Tape, Glue or Bond Aluminum Plate to HDPE?



## C4C (Aug 27, 2016)

I am adding my Lowrance Structure Scan Transducer to the rear of my skiff. The transducer is already bolted to a 6061 T6 aluminum plate the is form fitted perfectly to my hull. Now all I have to do is tape, glue or bond the aluminum plate to my high density polyethylene hulls, without bolts, screws, or modifying the hulls in any way. I wanna stick it and forget it.

Anyone have any experience attaching dissimilar materials to hdpe, so my transducer does not pop off every time a gator wraps a line around it?


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## Stickbow (Aug 31, 2016)

C4C said:


> I am adding my Lowrance Structure Scan Transducer to the rear of my skiff. The transducer is already bolted to a 6061 T6 aluminum plate the is form fitted perfectly to my hull. Now all I have to do is tape, glue or bond the aluminum plate to my high density polyethylene hulls, without bolts, screws, or modifying the hulls in any way. I wanna stick it and forget it.
> 
> Anyone have any experience attaching dissimilar materials to hdpe, so my transducer does not pop off every time a gator wraps a line around it?



Quickest answer is that pretty much nothing sticks to HDPE. That's what high density polyethylene it was designed for, and why it is used for buckets/barrels/etc. Mechanical fasteners are the very best solution, especially if you expect a gator to wrap a line around it.

There are some epoxies that claim to work. West Systems has a product called G-Flex (instructions here), but the couple of times I tried it on hdpe kayaks it only sorta worked.


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## C4C (Aug 27, 2016)

One question, did you flame treat your HDPE first?

I guess I will be doing some experimenting myself, I bought:
J-B Weld 50133 Plastic Bonder Structural Adhesive
J-B Weld 8272 MarineWeld Marine Epoxy
J-B Weld 8277 WaterWeld Underwater Epoxy Putty
Marine Tex Marine Rapid Set

If and when these fail, I am laser cutting a mechanical mount that bypasses the HDPE hulls altogether.


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## tjtfishon (Feb 9, 2016)

There is a product called Stern Saver which is a starboard plate that uses epoxy to bond to your stern so you can use mechanical fasteners for your transducer to it instead of holes in your boat. Since it is made of starboard which I believe is also HDPE and the glue can stick to it I imagine it will also stick to your skiff?

What are you driving?


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## WhiteDog70810 (May 6, 2008)

I don't think epoxy is the answer. Epoxy doesn't stick to aluminum or HDPE. You can rough up the surfaces and it might not fall off as fast, but it will still fall off. 5200 alone might hold longer. I'd bolt it on and use 5200 if I wanted it to resist any torsion.

Nate


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## anytide (Jul 30, 2009)

nothing works very well structurally as a bond other than fasteners...
it can be welded or adhered.
i handle a lot of it daily.
http://www.sdplastics.com/ppx5ultimateplasticbonder.html


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## C4C (Aug 27, 2016)

The key to getting anything to stick to HDPE is to pre-treat the surface with heat and then roughen the surface. HDPE naturally beads water and is practically unstickable. But if you heat treat it, the surface will become shiny and water will now "smear" rather than bead. Then I roughen the surface with a sand blaster. If water beads nothing I have found will stick.

I have tried Mr. Sticky polybonder, 3m 5200 and PVC Cement which is decent but shears off without tearing the HDPE so there is not a significant bond. I have had really good success with 3M Scotch-Weld DP8005 but it takes perfect prep and it dries BLACK. My HDPE hulls are yellow, so black is just not going to work.

If I could find a solvent that melts HDPE together, rather than just adhere, I could easily switch to HDPE plates instead of aluminum.

My boat is an ocean going pontoon boat made entirely of 6061 T6 aluminum except for the Wilson 36" diameter HDPE pontoons, however the boat is still under construction so all I have are my CAD drawings.

This "pontoon" boat will also house my CraigCat tender boat (which is also yellow HDPE). Sorta mini-house boat style.


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## anytide (Jul 30, 2009)

are you asking how to or telling how to?
daam thats yellow!

you hunt gators in a craig cat?


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## Stickbow (Aug 31, 2016)

C4C said:


> One question, did you flame treat your HDPE first?
> 
> I guess I will be doing some experimenting myself, I bought:
> J-B Weld 50133 Plastic Bonder Structural Adhesive
> ...



I have tried heat treating/roughing as mentioned by others and just straight 'roughing with sandpaper' then gluing with a bunch of different adhesives - gave up and learned to plastic weld hdpe and use through fastening when needed. I only mentioned the West System product because a few other people have said they had success - I would not consider my attempts with it successful.

My experience is with HDPE kayaks, by the way. I don't believe that is a radically different "HDPE" than any other.


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## Stickbow (Aug 31, 2016)

C4C said:


> If I could find a solvent that melts HDPE together, rather than just adhere, I could easily switch to HDPE plates instead of aluminum.
> 
> .


Hope I did the quote right...

The answer is heat vs. a solvent, I believe. If you are trying to bond large areas you will have to have specialized equipment, I think (if it's possible). As an amateur repairing/fabricating, I have done a lot of small scale "plastic welding", but not tried more than essentially edge welding pieces to repair large holes, essentially spackling cracks, and some minor fabrication of plastic sheet from HDPE scrap to make parts.


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## permitchaser (Aug 26, 2013)

tjtfishon said:


> There is a product called Stern Saver which is a starboard plate that uses epoxy to bond to your stern so you can use mechanical fasteners for your transducer to it instead of holes in your boat. Since it is made of starboard which I believe is also HDPE and the glue can stick to it I imagine it will also stick to your skiff?
> 
> What are you driving?


I tried to bond starboard with industrial adhesive and it did not stick


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## C4C (Aug 27, 2016)

anytide said:


> you hunt gators in a craig cat?


My next hunt is September 12th at the Santee Coastal Wildlife Management Reserve. Hunting from such a small boat tends to keep your awake when hunting at night.

So I decided to avoid modifying my hulls all together by designing some 6061 T6 aluminum sonar transducer mounting brackets which I bolted to the motor mount.


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## anytide (Jul 30, 2009)

is that a yes...


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