Aluminum bonding

http://www.practicalmachinist.com/vb/general/bonding-aluminum-epoxy-236706/

hysol ea 9390 for oxide free surface, else aluminum bond will come lose.

https://www.lord.com/products-and-solutions/adhesives/versilok-253254-adhesive LORD Versilok® 253/254 adhesive is a two-component, epoxy-modified acrylic adhesive used to bond a variety of automotive sheet metals, including hot-dip galvanized, electro-galvanized, bare aluminum, and cold rolled steel. Versilok 253/254 adhesive can be either room temperature cured or heat cured for faster processing. Glass beads are included in the adhesive system providing a mechanical lock between substrates. Versilok 253/254 adhesive is approved by General Motors Corporation (3639M) and Ford Motor Company (ESB-M2G347-A).

JB weld
better than lab metal, 3m loctite. I drilled 1/16holes through the joint, jb weld fills the holes. https://www.jbweld.com

problem here is potential for galvanic corrosion, so fiberglass is bonded inbetween the two alum. pieces or special coatings on alum to prevent this. (''The parts we have bonded have been bare 7075 t6 AL and anodized 7075 AL but we strip the anodizing of the area to be bonded, per 3M recommendations. As far as galvanic corrosion we haven't had it be a problem, or be something that anyone has brought up to us when we initially researched the concept. As far application its nothing military or proprietary race stuff, just a Formula SAE race car. We use CF roll-wrapped a arms and pulltruded sway bar and steering links.

The 3M stuff we use, which I will get a PN for soon uses a gun and special disposable tips that are one time use.'')

Scrim is spiderweb like material between two joints, if pieces are just clamped, there are voids and no place for the glue to bond, leading to join separation.

Lotus Car Group uses a one part adhesive, (I think Ciba) with fancy heated sheetmetal screws, driven by robots, to build up the Elise & Exige chassis elements, and the whole mess is then autoclaved. here's a Lotus link, which contains some other links to Bonding/engineering sites, which may give guidance: * http://www.lotustalk.com/forums/f101/what-adhesive-used-bond-elise-chassis-71543/

Composite engineering Forum - Eng-Tips
 * http://www.eng-tips.com/threadminder.cfm?pid=327

links
http://www.eng-tips.com/threadminder.cfm?pid=327 Eng tips. Machine design