# What is the Best Epoxy Glue to Glue 6061 Tubes?

Discussion in 'Tube and Fabric' started by Armilite, Mar 12, 2015.

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1. Mar 12, 2015

### Armilite

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What is the Best Epoxy Glue, to Glue 6061 Tubes in 1.0" to 3.0"? In .058" to .080" wall.

2. Mar 12, 2015

### kent Ashton

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Perhaps ProSeal will work for you. Epoxy generally makes a weak, fragile bond to aluminum and any stress will break the bond. Pro seal is rubbery and more forgiving but neither is as secure as rivets or welding

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3. Mar 12, 2015

### BJC

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What is the application?

BJC

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4. Mar 12, 2015

### cheapracer

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I did lots of tests recently, the conclusion is rivets as primary with the epoxy only in a secondary joint stabiliser role. I'm with Kent above, a slightly more flexible product is preferable (again, in secondary role) and my choice is one of the "No Nails" type adhesive products.

There is no magic epoxy for metals unless you are big time, car companies such as GM, Benz and Lotus etc use bonding without fasteners or only anti peeling fasteners, but they spend millions for 'exclusive to their needs' products and make use of curing ovens in some cases.

5. Mar 12, 2015

### BoKu

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Really. The question is pretty much meaningless without knowing what the joint geometry is.

There have been a few places where I needed a high-strength bond between 6061-T6 tubing and a precision-fitted sleeve. I used Hysol EA9430.

Thanks, Bob K.

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6. Mar 12, 2015

### Victor Bravo

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You will find the best adhesive is called AN470

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7. Mar 12, 2015

### Rconc

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I am not familiar with EA9430 but 3m 2216 is a good epoxy that does retain some flex. Metal bonding requires surface prep and primers to protect the bondline. I have heard of a primer EC3901 that can be used with 2216 but it would require you research it.

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8. Mar 12, 2015

### Norman

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9. Mar 12, 2015

### cheapracer

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To be noted ..

10. Mar 14, 2015

### TJay

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I used Hysol 9460 for everything on my kitfox, it works great, I have found if you are sticking it to 4130 you should prime first but for aluminum and wood it holds way better to bare surface.

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11. Mar 16, 2015

### Armilite

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======================================
Part103 Ultralight. Maybe also use for Carbon Fiber Tubing.

Years ago, I watch a TV show on Adhesives. The guy took two 1/4" thick Steel Plates, about 3" x 9" and squirted some Epoxy Glue on the two, about half & half, and then layed them together. After they cured, don't remember how long that was, but they were placed in a Hydraulic Machine that pulled on the Two Plates Lenght wise till they came apart. The metal tore in half before the Glue part came apart!

Months after that show, I bought some cheap 2500lb Walmart 2 part Epoxy Glue. I had a Military Generator with a metal part that was glued on the Plastic Type Gas Tank for the locking gas cap. I took that Epoxy Glue and spread it around the pieve with a Q Tip, and put it back on the Tank. I wanted the Cap to make the chain tight when locked on, so I also put the Cap on. I let it dry over night. The next day I went to turn the Cap off, and I couldn't turn it. I used a Big Pipe wrench and couldn't turn it. So I put a 3' piece of tube over the handle, and it took all I had to get it broke loose. I was 6' 290lbs then. When I got it broke loose with the cheater Tube, I looked under the Cap, two holes about a 1/8" allowed Expoxy to leak thru to bond the two parts together. That impressed me on it's holding strenght.

So I had the idea then, why not Epoxy Glue the Tubes for a Part103 Airframe, like PVC Tubes. Use either 6061, or Carbon Tubing. And use Rivets where needed to save the weight of all the Bolts & Nuts & Washers. I haven't found any good connectors to try it yet.

Rich

Last edited: Mar 16, 2015
12. Mar 16, 2015

### Jay Kempf

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Actually Lotus and Panoz have gone to adhesive suppliers that also make the products available retail. Lotus used an oven cure two part injectable which is probably not practical for homebuilt projects but the adhesive that Panoz used was developed by a little company in NH but now is available through ITW Plexus. The adhesive is a Methylcrylate. I have used this stuff on raw aluminum without prep and it's performance was impressive. This is the future of aluminum structures. You have to learn to design bond area in the right directions and with the right area and protect against peel but those are fairly straightforward things to learn. There are several blends of this stuff for viscosity and speed of cure. It can be injectable or just run a bead and clamp sort of applications. When I was experimenting with this stuff we had to design a pressure and volume dosing gun for injecting joints that were designed to be done in one push of the button for a production application. Very promising. 3M has been experimenting with high density foam double stick tapes for joining panels as well. That shows some real promise as well because you can form and then coat a panel and then attach it without scratching or penetrating the coating. And the performance is pretty amazing for tensile, peel and shear.

13. Mar 16, 2015

### BoKu

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Many epoxy formulations are good for 2ksi, and some high-strength blends are good for 4.5ksi. Given 27 square inches of bond area, with the good stuff you ought to get around 120k lbs of tensile capacity. Depending on how the coupons are shaped and assembled, it's not beyond reason that you'll break part of the coupon.

What epoxies generally suck at is T-peel. Given a T coupon made of two lightweight aluminum L shapes glued back to back, it's typical to see 5 lbs per linear inch, with the very best formulations going to 60 lbs per linear inch. So, best to avoid loading epoxy joints such that prevailing forces can peel them apart.

It's all about the joint geometry. Butt joints are a non-starter; there's just not enough bond area to get anywhere near the strength of the tubing you're joining. Scarf joints would be so long as to be unwieldy. Sleeve joints like with PVC tubing, as you suggest, would be best. But in a typical airframe there are dozens if not hundreds of different joint geometries to address.

Thanks, Bob K.

14. Mar 16, 2015

### pictsidhe

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Acrylic or polyurethane works far better on aluminium than epoxy

15. Mar 16, 2015

### Lucrum

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I'm no expert in this area and I don't mean to rain on anyone's parade.
But the idea of aluminum tubes and epoxy for anything bearing a load gives me the willies.

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16. Mar 16, 2015

### BJC

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If you are not familiar with Leo Loudenslager's efforts to build the lightest aerobatic monoplane possible, with some wild aerodynamic comtrols see this video:

BJC

17. Mar 16, 2015

### Jay Kempf

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And it should. But, and this is a significant one, if you do the proper prep/etch of the surface and use the correct epoxy and match the alphas of the two bonded materials it can be done. Alex Strojnick did just that in the S-2 spars and other parts of the design. Highly loaded. There are way better ways to do that now but even 20+ years ago people were way out of the box doing bonded structures. The BD-4 had non structural skin put on with rivets every 6 or so inches and contact adhesive and it worked fine. Design the bond properly, prep the materials properly, don't overload the adhesive properties and it will work.

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18. Mar 16, 2015

### Lucrum

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I hadn't seen that one before

19. Mar 17, 2015

### Armilite

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Dragon Plate use's these Epoxy Glues below for Carbon Tube parts. Some below, I see have also been reccomended above also for 6061 Tube. My idea, is to have something that sets up fast like PVC Glue does. Just apply, insert, and line it up, hold it in place for a few minutes, then set done and let dry over night. If applying some Heat, helps it cure faster, maybe put in makeshift electric oven. But I can wait 24hrs. Then Glue smaller assemblies to make bigger assemblies.

For a Part103 Type Airframe, we only probably need, a Splice for Joints, a 90 Elbow, a 45 Elbow, a Tee, a Four Way cross, maybe a X Type Cross, a End Plug, a Spar Sleeve Tee, like one part 2.5" with a 1" small part for making Wings. I'm sure there are a few others, but not that many.

Rich

[TABLE="width: 100%"]

[TD="class: productRow1, bgcolor: #F0F0F0"]Double/Bubble Black Regular Setting Epoxy Adhesive
HARDMAN Regular-Setting Epoxy is a two component, room temperature cure epoxy system designed to set in 45 minutes in a thin (10 mil) film. 3.5 gram foil pack.
[TD="class: productRow1, width: 80, bgcolor: #F0F0F0"][/TD]
[TD="class: productRow1, width: 100, bgcolor: #F0F0F0"]$1.50 USD [/TD] [TD="class: productRow2"]Double/Bubble Orange High Peel Strength Epoxy Adhesive HARDMAN High-Peel-Strength Epoxy is a semi rigid, two component structural epoxy adhesive with a 3 hour work time. Excellent combination of shear strength and peel strength. 3.5 gram foil pack More Info[/TD] [TD="class: productRow2, width: 80"][/TD] [TD="class: productRow2, width: 100"]$1.40 USD

[/TD]

[TD="class: productRow1, bgcolor: #F0F0F0"]3M Scotch-Weld Epoxy Adhesive 2216 B/A Gray Tube Kit
Highly Flexible, Two-Part Adhesive Kit highly recommended for DragonPlate bonding. Available tube or pint kit size.
[TD="class: productRow1, width: 80, bgcolor: #F0F0F0"][/TD]
[TD="class: productRow1, width: 100, bgcolor: #F0F0F0"]$52.50 USD [/TD] [TD="class: productRow2"]3M Scotch-Weld Epoxy Adhesive DP110 Gray 50ml Duo-Pak 3M Scotch-Weld Epoxy Adhesive DP110 is a flexible, two-part epoxy. 1:1 mix ratio, 10 minute work life and handling strength in 20 minutes. Dispensed with a 3M Scotch-Weld EPX Plus II applicator. 1.7 oz/50ml More Info[/TD] [TD="class: productRow2, width: 80"][/TD] [TD="class: productRow2, width: 100"]$24.60 USD

[/TD]

[TD="class: productRow1, bgcolor: #F0F0F0"]3M Scotch-Weld Epoxy Adhesive DP190 Gray Duo-Pak
3M Scotch-Weld Epoxy Adhesive DP190 is a gray, two-part epoxy. 1:1 mix ratio, 90 minute work life and handling strength in 12 hours. Dispenses with 3M Scotch-Weld EPX Plus II applicator. 1.7 oz/50ml
[TD="class: productRow1, width: 80, bgcolor: #F0F0F0"][/TD]
[TD="class: productRow1, width: 100, bgcolor: #F0F0F0"]$24.60 USD [/TD] [TD="class: productRow2"]3M Scotch-Weld Epoxy Adhesive DP420 Off-White 37ml Duo-Pak 3M Scotch-Weld DP420 is a 2-part off-white epoxy adhesive with outstanding shear and peel adhesion, very high levels of durability, controlled flow, a 2:1 mix ratio, 20-30 minute worklife, and develops handling strength in 1-2 hours. 37ml More Info[/TD] [TD="class: productRow2, width: 80"][/TD] [TD="class: productRow2, width: 100"]$24.60 USD

[/TD]

[TD="class: productRow1, bgcolor: #F0F0F0"]3M Scotch-Weld Epoxy Adhesive DP420NS Black 37ml Duo-Pak
3M Scotch-Weld Epoxy Adhesive DP420NS is a black, non-sag, toughened, two-part epoxy adhesive. 2:1 mix ratio, 20 minute work life and handling strength in approximately 2 hours. Requires EPX Plus II applicator gun to dispense. 37ml
[TD="class: productRow1, width: 80, bgcolor: #F0F0F0"][/TD]
[TD="class: productRow1, width: 100, bgcolor: #F0F0F0"]$25.45 USD [/TD] [TD="class: productRow2"]3M Scotch-Weld Epoxy Adhesive DP460NS Off-White 37ml Duo-Pak 3M Scotch-Weld Epoxy Adhesive DP460NS is a toughened, non-sag, two-part epoxy. 2:1 mix ratio, 60 minute work life and handling strength in 4 hours. Requires 3M Scotch-Weld EPX Plus II applicator gun to dispense. 37 mL More Info[/TD] [TD="class: productRow2, width: 80"][/TD] [TD="class: productRow2, width: 100"]$26.50 USD

[/TD]

[TD="class: productRow1, bgcolor: #F0F0F0"]3M Scotch-Weld Epoxy Adhesive EC-2216 Gray 43M Duo-Pak
3M Scotch-Weld Epoxy Adhesive EC-2216 is a gray colored, flexible, two-part epoxy. 2:3 mix ratio, 90 minute work life and handling strength in 10 hours. Dispensed with 3M Scotch-Weld EPX II Plus Applicator. 43 mL
[TD="class: productRow1, width: 80, bgcolor: #F0F0F0"][/TD]
[TD="class: productRow1, width: 100, bgcolor: #F0F0F0"]\$18.75 USD

[/TD]

[TD="class: productRow2"]3M Scotch-Weld Low Odor Acrylic Adhesive DP810, black 50ml Duo-Pak
3M Scotch-Weld Low Odor Acrylic Adhesive DP810 is a toughened, two-part black acrylic adhesive. 1:1 mix ratio, 10 minute work life and handling strength in 20 minutes. Dispensed with 3M Scotch-Weld EPX II Plus Applicator. 50ml
[/TABLE]

20. Mar 17, 2015

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