[Tchleung]

Awesome, well I found a couple dealers that can get the structural foam, so it seems as if the 83 42 0 307 530 number is still available. Now I just gotta buy the applicator gun and buy some seam sealer.

[e46Chicago]

I did a couple hours more research on this, over the weekend - and if you can wait till later today I can post up the sources and prices I found for all the stuff. I've found a 3M structural foam and a Lords that appear to be as good or better as well as a Wurth seam sealer and a 3M seam sealer that also have been recommended well.

I will post up all my info later today. . .

and if anyone knows where I can get a metric stepped drill bit (I'd sort of like to just have one anyway, not solely for the subframe repair) let me know!

Oh - and on the TIS it mentions needed 2 different size body plugs, but I didn't see why/where to use them (maybe I skimmed it over too fast or something?)

-r

[Tchleung]

I think the body plugs are to seal up the two holes you drilled to inject the seam sealer. So you'd need 3 if you are doing the right side as well.

[e46Chicago]

To help cut down on having to order products at various places with potentially different dispensing guns, etc. I think I'm going to go with the following, unless someone has a good suggestion why this wouldn't be advisable.

Seam sealer: (in a later version of the TIS they say techs can use "Wurth seam sealer," but the Wurth sealer in a gun is actual sorta hard to find, so I think I like this one) - 3M Automix Heavy-Bodied Seam Sealer - 08308 $29.59.

Non sagging and non flowing means it's the kind we want, the kind that can fill a small three dimensional void and seal off a side of it. It's 3M, so it probably won't be a lemon.


Structural foam: 3M Automix Pillar Foam - 08458 $36.59. I liked this because they said it's OEM spec and can "fill and straighten body cavities." Also, it uses the same applicator gun as the seam sealer above, these applicator guns are like $50 each so, that's nice.


And to secure the turner reinforcement plates from underneath (at a later date) this epoxy: 3M Automix Panel Bonding Adhesive - 08115 $37.29. This is the epoxy recommended in the original post in this thread.

I was reading up on that Epoxy, and if you do go that way, FYI it looks like taking a hair dryer or heat gun (on low) to it for a little while will drastically speed up your cure (like you could get it down to an hour, paintable later that day probably). Like wise, you'd have more work time if it was a 50deg day or something.

And this looks like an applicator gun that will handle all 3 of those products for about $50. 3M Manual 200 mL Cartridge Applicator Gun - 08571

I picked this place w/ some randomness, so if you wanted to use the p/n's and buy elsewhere, please let me know if you find better prices. And like I said if you have thoughts/suggestions on my product choices I'm all ears.


And further stuff for underneath, while you're shopping. . .
Self etching primer to spray on the turner reinforcement plates and around any area you've sanded down there. Dupli-Color Aerosol Self Etching Primer - DPP101. $8

And I'm also probably going to buy a bunch of this, undercoating spray, since I'm going to be dropping just about everything south of my U joint as I do my Turner plates and a suspension refreshing. SEM Rubberized Undercoating Low VOC - 40523 It's about $10 @ can, but it's 24oz, which is big. And I think these products have come a long way in the last 10 years. . .they actually sorta work.

The underside of my car has been ravaged by nothing, so I'm not holding back now as I defend its corrosive assault. All steel parts are being replaced or overhauled and probably Rhino coated, all metal fittings and hardware replaced w/ OEM stuff that I'm going to have coated for corrosion resistance, all aluminum parts are getting shampooed with agave nectar and a loofa. . .lol, but at least they are pretty easy to get looking nice.

Lastly, if I fill the right side with foam, I don't need to make any barriers w/ the seam sealer, right? I'm just filling another cavity with the foam?

It's this large one in the middle that we're talking about, right? It's hard to make out now that it's a B&W sketch.


Are there any other hollow voids that we can fill up with foam to increase structural rigidity and/or decrease NVH?

Oh and if you really, really want a stepped metric uni-bit to drill out the 10mm hole (though I'm sure 3/8" is good enough for sane people) I found a real nice one on

Amazon.com: Irwin 16101 Unibit1MT Titanium Nitrate Coated 4-Millimeter to 12-Millimeter by 1/4-Inch Shank Step Drill Bit: Home Improvement

Amazon.com: Irwin 16101 Unibit1MT Titanium Nitrate Coated 4-Millimeter to 12-Millimeter by 1/4-Inch Shank Step Drill Bit: Home Improvement

[drunk hal]

^nice work gathering all that info, I'll probably be doing this cavity foam eventually even though I have a weld-in kit, it's too cheap not too imo

[e46Chicago]

Originally Posted by drunk hal

^nice work gathering all that info, I'll probably be doing this cavity foam eventually even though I have a weld-in kit, it's too cheap not too imo

Thx. . .ya, it's almost a no brainer. . .especially because you can do the 2 turner plates from the bottom w/ epoxy (a fact which this very forum & thread enlightened me on), this potentially turns the whole thing into a $200 DIY on a Saturday vs. a 1-2 day MIG welding fest at your local shop. I'd rather put that $$ into other fun stuff my car needs. In the TIS BMW clearly recommends you make structural changes to the car (i.e. new subframe among other things) if you have I want to say X number of cracks over 20mm or more, but if you have just a couple of cracks 10mm or less, or no cracks at all (yet), like me - then it's structural foam all the way. . .so I'm going to tackle this the $200 DIY way, especially since I totally dropped the ball on that settlement crap.

HTH!

[drunk hal]

Originally Posted by e46Chicago

this potentially turns the whole thing into a $200 DIY on a Saturday vs. a 1-2 day MIG welding fest at your local shop.

It's a lot of work taking it all apart, I'd at least plan to have the car out of commission for the whole weekend so everything could cure. Start taking it apart Friday night and have the plates epoxied in by Saturday noon so it can sit and cure (along with the cavity foam) undisturbed for +24 hrs. Only potential drawback is if you do find cracks you'd have to put it back together and take it to someone, but the payoff for getting it done DIY style is worth the chance you waste some time and have to put it back together imo. Mines already welded up though so all I'll be doing is the foam.

[genuity]

Originally Posted by e46Chicago

Lastly, if I fill the right side with foam, I don't need to make any barriers w/ the seam sealer, right? I'm just filling another cavity with the foam?

There is a hole on the right side under the sound deadening but it is not in the same location as the one on the left. If you look at the sheet metal pattern while you are in there, you will see. Injecting seam sealer into the holes under the sound deadening seal off the cavities to the front of the sheet metal sections. As you inject the structural foam, it will fill up the cavities and expand as it cools and dries. The seam sealer's purpose is to isolate the foam to a certain areas, namely around the rear mounts.

"Non sagging and non flowing" seam sealer is what you want to use if finding an alternative. DO NOT go for the cheap stuff. Not all seam sealers are the same. Cheap seam sealers tend to be soft and mushy. Wurth or 3M but not the crap you find on the shelves at your local auto parts. By the way, they keep the good stuff in the back, so you have to ask for it if they actually have it. Keep in mind that once you open the seam sealer there is no going back or saving it for later, so use it or lose it. Load up on two cartridges of the seam sealer as you will need it, that is if you are planning on injecting the structural foam into both sides, and assuming you are able to locate the other hole to seal off the right cavity.

[e46Chicago]

Originally Posted by drunk hal

It's a lot of work taking it all apart, I'd at least plan to have the car out of commission for the whole weekend so everything could cure. Start taking it apart Friday night and have the plates epoxied in by Saturday noon so it can sit and cure (along with the cavity foam) undisturbed for +24 hrs. Only potential drawback is if you do find cracks you'd have to put it back together and take it to someone, but the payoff for getting it done DIY style is worth the chance you waste some time and have to put it back together imo. Mines already welded up though so all I'll be doing is the foam.

To be honest, I'm still formulating my plan of attack from below because there are *so* many things I want to do, and I'm still slowly accumulating parts. In a perfect world - brakes at all 4 corners, ever single bushing replaced, springs, shocks, sway bar, a lot of stuff cleaner and paint or powder coated, Z4m finned diff cover, etc., etc. I'd *love* to put on a LSD, but I don't think I can make that work financially right now w/ my M54B25 slushbox. It sucks there are no plug and play drop ins available from other models.

All I need is a lift for a couple days or a week, and a replacement daily driver, and I can finally make these unhealthy dreams come true.

But for this weekend, foam up that a/c condensor and clean out that mustiness.

[e46Chicago]

Originally Posted by genuity

There is a hole on the right side under the sound deadening but it is not in the same location as the one on the left. If you look at the sheet metal pattern while you are in there, you will see. Injecting seam sealer into the holes under the sound deadening seal off the cavities to the front of the sheet metal sections. As you inject the structural foam, it will fill up the cavities and expand as it cools and dries. The seam sealer's purpose is to isolate the foam to a certain areas, namely around the rear mounts.

"Non sagging and non flowing" seam sealer is what you want to use if finding an alternative. DO NOT go for the cheap stuff. Not all seam sealers are the same. Cheap seam sealers tend to be soft and mushy. Wurth or 3M but not the crap you find on the shelves at your local auto parts. By the way, they keep the good stuff in the back, so you have to ask for it if they actually have it. Keep in mind that once you open the seam sealer there is no going back or saving it for later, so use it or lose it. Load up on two cartridges of the seam sealer as you will need it, that is if you are planning on injecting the structural foam into both sides, and assuming you are able to locate the other hole to seal off the right cavity.

Great input, thx! First off, I've been too much of a prick to be able to shop at the home depot for a few years now, because they don't have the quality of hardware that I demand, for the most part. . .I say this only in half jest. Trips to Pep Boys or Auto Zone are for emergency (usually subpar) wax, that's it! This gets even more hysterical if you were to see my wardrobe of non 9a-5p clothes. New clothes are easily picked out by people who barely know me by their lack of paint and grease stains. I'm still waiting for my town to finally relax their rules on medium size diesel engines operating at residential locations, so I can finally get the air compressor of my dreams. lol. . .

On "the right side" tangent - does that pic I tried to post show up for you? Do you see the holes on the right side that you're thinking of? I think I see some. And we're saying that no seam sealer is necessary on the right?

Thx!