heinzboehmer's 2002 Topaz 6MT Coupe

[heinzboehmer]

Purple!



Surface temps ended up settling at around 60C. 07333 Datasheet.pdf says that you should cure the adhesive for an hour at 60C, so I did that. I'm assuming the adhesive further in will have cured less, but I'm still a couple days away from having the car back on the road, so it should have enough time to fully cure.

I do have to say that 07333 is awesome to work with. Working time is super long and it's fairly viscous, so it doesn't make a mess. Curing can also be accelerated easily, which is always appreciated.

[heinzboehmer]

This should actually work:



Started with the last bit of prep. Masked the bottom of the aluminum piece so I wouldn't get adhesive on the bearing surface. Did the same to the top of the blower motor housing:



No pictures, but I removed the masking tape on the chassis and found no surface rust, nice. Still give it a super quick sand with 220, then the acetone + IPA wipes. Same with the aluminum piece.

Then I wet both surfaces out. Doing that on the chassis was not easy. Had to use a brush and a mirror, but I got it done:



Did the same on the aluminum piece and then did my best to apply an S-ish shaped bead. Again, decently hard to do with the aluminum piece in one hand and the giant applicator in the other:



Grabbed that piece + the greased up bolt beneath it and got it situated in place. Bolt got torqued and any adhesive that squeezed out got cleaned up.

Then blower motor housing and wedges got put in place:



And finally, sketchy space heater was added to help the adhesive cure:



Initial temp readings aren't super high, surfaces were at around 30C with the heater going. 3M says to not exceed 80C for more than half an hour, so should be totally fine. Will see what the temps get to in a couple hours.

[heinzboehmer]

Documented the blower motor stuff in much greater detail here: https://nam3forum.com/forums/forum/m...or-replacement

I feel like I've finally developed a decent approach for that job and I just know that I would have forgotten it within days had I not written it down. Also serves as proof that blower motor replacement is possible with my piece permanently bonded to the chassis!


I did also do a few more things as pre-bonding prep.

Applying the adhesive with the blower motor housing out is gonna be much easier. However, no housing means I have nothing to wedge against and would have to leave the flat section of the piece just kinda floating in midair. Decided to strip down the right side flap assembly so that it's very easy to install (the easier the better cause I'll be rushing when it comes time to apply the adhesive), but still has enough structure to wedge against:



Linkage also came out as it kinda gets in the way of the quick install. Actuator rod needs to be popped out (downwards), back crank tab needs to be released and then the entire linkage falls out:





Plan is to have the plastic flap frame hanging out to the side while I do all the adhesive stuff, like so:



Then hold the aluminum piece in with the front bolt and rotate the flap frame into position. With it in place, I can add the wedges and wait for it to cure:




You might notice there's a bunch of tape over the metal surface I prepped before the adhesive incident. Did this to minimize surface rust that might form while I wait for the replacement adhesive to arrive (thanks again for the tip Bryson!). We'll see how well this worked soon.

Lastly, I swung by tlow98's place and used his big ass vise to press the studs into the E86 brace attachment point:



I printed those press tools so that I wouldn't mar the aluminum and they worked great!





Printed with 100% infill, as I figured this was a good place to go overkill. They honestly still look amazing, I bet I could have made them way less beefy and it would have been fine.

[smee123]

Surface prep is king with 3m structural adhesive just like the importance on the loctite and their activators. Maybe trivial on an oil pan drain time sert l, but on anything that experiences any pulling loads or any inherent vibrations, I cant stress it enough!!

[heinzboehmer]

Maybe I missed it...any reason you chose 07333 vs 08115 (panel bond)?

Based on 3Ms own recommendation

07333 is for structural stuff, 08115 is for non structural body panels:

3M Panel Bonding Adhesive Designed to meet specific strength requirements for outer
sheet metal panel replacement; panel bonding adhesive is
typically used in conjunction with welding, rivets or hem
flange joints. Panel bonding adhesives do not offer the same
level of impact resistance as impact resistant structural
adhesives and should not be used for structural repairs unless
recommended by the specific automotive manufacturer.

3M Impact Resistant Structural Adhesive
Designed to meet specific strength requirements for parts
such as frame rails, strut towers, sills, pillars and other
members where impact resistance is important. This type of
adhesive possesses a much greater ability than traditional
bonding adhesives to absorb and manage energy under a
variety of forces, especially peel and cleavage stresses in
extreme temperature conditions. Typically
impact resistant structural adhesive is used in conjunction
with rivets, spot welds or mechanical fasteners.

Document where that quote came from is attached.