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Looking good!

I would tie the shock mount in too if you can, though its challenging to make it bolt on and functional.

For the bolts for your bar, source the highest grade you can. Those are M6s as I recall (though they look like 8s to me in your photos, werid). I went with some high strength cap screws.

That stupid lump of steel! I have seen that before but totally forgot about it. Probably a NVH thing, I want to go and dig that out of all my cars now if it truly has no purpose.
 

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Discussion Starter #222
I can have a tab running from one of my bars to the shock mount for sure. I hadn't planned on it, but I want it all fairly removable anyway.

The bolts in those pictures are the stock seat latch bolts. However I have to find some bolts for the seat belt mount point and child seat mount point. Would Grade 8.8 or Grade 10.9 bolts be preferable? I guess might as well go highest grade.

It doesn't seem like it's possible that it is there for any sort of structural strength but I'm not sure? Maybe it prevents buckling at the center of that beam? It is way heavier than it needs to be for anything structural, and there is foam between it and where it contacts the roof sheet.
 

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Discussion Starter #223
More bracing. I got 90% of the way through twin to this one on the other side but it started POURING rain. The bay flooded and I decided I didn't need to be welding while standing in a puddle. They aren't quite identical as I'm doing a lot of Eyeball Engineering, off by about 1/4 inch in space. Right one is farther back from the shock tower than the left one. I don't think it's hugely important....











What on earth that hunk of metal does is still baffling me. Do I really need it? It's heavy and I would like to cut the weight out. I bet if anyone has removed it, it's that crazy nordic guy...
 

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What on earth that hunk of metal does is still baffling me. Do I really need it? It's heavy and I would like to cut the weight out. I bet if anyone has removed it, it's that crazy nordic guy...[/QUOTE]

It's for vibration damping. The mass of an assembly is related to its natural frequency. They probably had an issue with vibration in the roof at some frequency and the hack way of fixing this is to increase the mass of the assembly.
 

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Discussion Starter #226
Getting into some real fab now. Gotta be a nice change of pace.
I'm mostly doing this because I'm very nervous to put that quarter panel back on and want more practice. It is a refreshing change of pace though.

It's for vibration damping. The mass of an assembly is related to its natural frequency. They probably had an issue with vibration in the roof at some frequency and the hack way of fixing this is to increase the mass of the assembly.
So I can safely remove it then? Excellent.
 

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Yeah the stock seat latch bolts are only the first level of strength. The metric grading system is different, the FSRM covers it and shows what the different markings on the factory bolts mean. 8.8 is weak sauce, 10.9 isn't bad. 12.9 is king, but can be hard to find a lot of bolts in.
 

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Discussion Starter #228
Got some bolts today. Shockingly the local Home Depot actually had a decent selection of grade 10.9 for the seat latch mount and the child seat anchor.

Then grabbed some Grade 8 shoulder bolts for attaching my heim joints to make the structure removable.

Only issue was finding Grade 8 nuts for the heim joints I bought off fleabay. Turns out not a lot of places carry 1/2 - 20 nuts. I found some Grade 5, which I think might be adequate for a couple reasons.
- easiest way to attach the heim to the tubing is to weld the nut onto a cap at the end of the tube, welding is going to damage any heat treatment on the bolts I pick anyway.
- grade 8 apparently doesn't weld as easy - becomes more brittle.
- 1/2' is pretty large so I think the overall size, compared to like the M6 bolts, is going to be a primary strength of the joint compared to just a stronger bolt in the case of the other mounting points.

It's been too dang hot here in VA to do some fabricating. Shed today read 92 degrees, 60% humidity and when you get the welder going that's way too hot for me.
 

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Discussion Starter #229
It's coming along. Here is one side, it definitely warped a little when I was welding in that reinforcement place, as now you have to pull it a little to get all three bolts in, but they still go in and can be tightened down. I need to take some time to think about how I want to tie in the third leg of the triangle and possibly integrate the shock tower.
Hey Fiend, for the tower could I just have a plate running across it that the shock itself bolts through? I can't think of any other way to do it really.

 

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Discussion Starter #230
Here is a crappy cardboard mockup of how I'm thinking about tying this all together. I'd like that last link between the seat latch and the frame rail, just to make sure it's triangulated and the frame rail point doesn't rotate.

The only way I can think to tie in the shock mount is a plate tied into the seat belt - frame rail tube. Then to keep it from excessively bending and only minorly bending, T it off to the same tube. It will still be in the worst possible spot in terms of leverage on the tube but I can't think of many other options and it should be very effective in preventing up/down tower motion. Wont be effective against fore and aft motion, and slightly better at left to right. The wider the T the better.

 

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That could certainly work, but since you aren't exactly opposed to doing welding on the car itself, you might want to consider welding an ear to the shock tower itself with a hole in it, then bolting your bar to that ear. The shock itself is meant to have some isolation from the body the way it mounts with the rubber bushings, and its ok if it moves a little. But having the shock tower itself move isn't great.
 

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Discussion Starter #232
That would certainly be easier, and save me some hardware cost, so I like the idea already.

What implications would that have on rust issues in between the layers of metal composing the shock tower? I was already going to go over the majority of the car with fresh seam sealer, so if that is all is required, then that would be great.

You recommend Pro Form Seam Sealer right? Which kind? There seems to be epoxy, rubber and urethane options.
Also what is a good acid etch Primer you'd recommend?
 

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I see a bunch of spot welds on the shock tower portion the shock bolts too. Can't remember off hand what the piece of steel those attach looks like on the other side, but the ideal would be to weld above those spot welds where there is only 1 layer of steel so you can clean up the welds on both sides. No implications then, but yeah, welding where the spot welds are means you couldn't clean up the other side nicely.

I recommend this stuff for seam sealer. White for interior, black for the underside of the car. Rocker guard will actually shrink back a little when you spray overtop so it will look funny if you use the white on the underside.


I havn't found an Acid Etch I really hated yet. They all seems to work fairly well as advertised, unlike Weld Thru primers. Speaking of, Lordco (our local parts chain) just dropped Plastikote for Duplicolor so I am in the midst of trying out a new weld thru. A copper one, hope it works.
 

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Discussion Starter #234
I'll wire everything off and take a looksie when I get a chance. Seems like plenty of space to work with between the top and those spot welds.

I've been using the plastikote everywhere on my car as well as on my store of sheet metal. It seems to work pretty well for short term but if you look at it funny it scrapes off. I'm on my last can and I think I had to order it through a local supplier. Ironically the metal tops of the cans came rusted.

Thanks for the Pro Form rec. Rubber instead of urethane based? Aren't a lot of the newer urethane ones supposed to not dry up/shrink over time? Or have they solved that problem on the rubber based ones now as well?
 

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Discussion Starter #235
Here's what I'm working with on the tower.
There's a small segment of tower between the top reinforcement and the multi layer mess below the tower. Not a lot of flexibility there for tabs.


There is an opportunity here to stitch weld the top reinforcement plate to the tower, however it's pretty well spot welded from the factory and I'm not sure the risk/reward is worth it. Obviously I'm going to end up sealing all of this later anyway.




 

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Discussion Starter #237
Thinking about it more, I'm going to pass on tying in the shock tower for now. Between using my eyeballs and handtools for all my fabrication, and the distortion of welding, I already am having things slightly not line up. I had to cut the reinforcement plate on the right side to bend the plate back to flat and weld in a sliver to fill in the space, the left side I didn't have to do that, but I do have to pull a little to get everything lined up.
So here is where it sits, I'm going to clean up the welds and paint everything and move on to the next points - filling in the antenna hole, possibly front shock tower reinforcement, fill in the hole in the front metal where someone cut for the FMIC.
Then once I'm as prepared as I can be, gonna start on that quarter panel and rocker, which I'm incredibly nervous for.





 

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Discussion Starter #238
Took a lil bit of a hiatus, was working on a non-car project of mine, but I'm back.
I painted the rear brace, here's how it looks sans any hardware. It's a tight fit and I doubt I can tie in the wheel well or tower without being out of dimensions elsewhere.





Next up is something similar for the front shock towers, but with joints on both sides of the bar so I can be a little less precise and not have it bite me in the ass. This is not the final size piece.

The plan is going to be to have two sets of plates to slide the heim into, then bolt in place. For the shock tower I think it will be fairly straightforward, on one of fiends cars he mentioned if you peel away the first thin sheet, there is a thicker layer below from the shock tower top. (See here if photobucket works: https://www.celicasupra.com/forums/showthread.php?60985-82L-Bodywork-amp-Slow-Build/page16)
I remember fiend talking about removing that top corner thing and replacing it with something thicker and stronger. However I'm not sure how to go about doing that.. I was thinking remove the top brace, and then since I'm not sure I can easily replicate that curve on the bottom, replace it with a two part solution. One piece on the top and then a plate reinforcement for the corner, then welding them together as well as along the outside edges. Then welding the two plates for the brace to that support.


I know there is a rule of thumb for how wide your support plates should be when you're welding to thinner sheet, at least for roll cage attach points. But I can't seem to find the actual specs for that. Also would need a lot of prep and sealing to prevent rust with the overlap.
 
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