DIY Strut brace
07-12-2019, 04:11 AM
#16
Rennlist Member
Looking good!
The factory tabs/mounting points look like they depend a lot on the rigidity of the bar itself to keep from folding vertically. There's a slight stiffening rib formed into them but it's not a lot. the ideal grab points are probably the shock and spring towers since they are right where force is applied to squeeze or stretch the cowl. The braces on the Mark/Rob crossbar move the functional mounting further towards the towers, but more importantly move any horizontal bending away from those original mounting points.
Are you going to run a lower frame crossbrace? That would reduce the distortion in the front box and likely reduce the load on the top brace.
The factory tabs/mounting points look like they depend a lot on the rigidity of the bar itself to keep from folding vertically. There's a slight stiffening rib formed into them but it's not a lot. the ideal grab points are probably the shock and spring towers since they are right where force is applied to squeeze or stretch the cowl. The braces on the Mark/Rob crossbar move the functional mounting further towards the towers, but more importantly move any horizontal bending away from those original mounting points.
Are you going to run a lower frame crossbrace? That would reduce the distortion in the front box and likely reduce the load on the top brace.
jp 83 Euro S AT 57k
07-12-2019, 06:07 PM
#17
Chronic Tool Dropper
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jp --
I made a similar recommendation to SG in a PM.
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Sterling: Just use the round dowel for your first mock-up. This is to get the cut angles and lengths correct before you start cutting that expensive wing-tubing. If you want to play with tack-welding tubing, buy a stick of EMT and grind the galvanizing off around where you plan to weld. Else, your miter saw and a notebook to help you remember your cut angles, tape measure, the doweling and a pencil, hot-melt, etc will do it fast and easy.
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Thinking about this while working on something else, the actual brace could very easily be a piece of al flat stock with a longitudinal stiffening rib formed in it. --^-- ASCII art... It just needs to not fold when under compression loading. Take a look at how the flimsy factory brackets attach to the fenderwall (spotwelds IIRC), how they depend on the rigidity of the bar itself to work as they do, and decide how much better/easier it might be to make your own bolt-in brackets and place them at the forward location where the new brace will pass across. It will be easier and more effective than anything you might cobble together to try and use the tin-foil factory pieces. We get hung up trying to advantage the pieces that are already there and that's fine, but they are clearly a bit of an afterthought, trying to solve something that wasn't identified in the basic chassis design stages. Torsion-box twist while cornering hard or lifting, maybe some cowl shake at speed. Looking at the factory mounts, it wasn't much 'cuz they are wimpy at best.
I made a similar recommendation to SG in a PM.
----
Sterling: Just use the round dowel for your first mock-up. This is to get the cut angles and lengths correct before you start cutting that expensive wing-tubing. If you want to play with tack-welding tubing, buy a stick of EMT and grind the galvanizing off around where you plan to weld. Else, your miter saw and a notebook to help you remember your cut angles, tape measure, the doweling and a pencil, hot-melt, etc will do it fast and easy.
-----
Thinking about this while working on something else, the actual brace could very easily be a piece of al flat stock with a longitudinal stiffening rib formed in it. --^-- ASCII art... It just needs to not fold when under compression loading. Take a look at how the flimsy factory brackets attach to the fenderwall (spotwelds IIRC), how they depend on the rigidity of the bar itself to work as they do, and decide how much better/easier it might be to make your own bolt-in brackets and place them at the forward location where the new brace will pass across. It will be easier and more effective than anything you might cobble together to try and use the tin-foil factory pieces. We get hung up trying to advantage the pieces that are already there and that's fine, but they are clearly a bit of an afterthought, trying to solve something that wasn't identified in the basic chassis design stages. Torsion-box twist while cornering hard or lifting, maybe some cowl shake at speed. Looking at the factory mounts, it wasn't much 'cuz they are wimpy at best.
07-12-2019, 06:25 PM
#18
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Last edited by Bigfoot928; 05-23-2020 at 03:04 PM.
07-12-2019, 06:59 PM
#19
Chronic Tool Dropper
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I wasn't suggesting moving the factory brackets. Make new ones and bolt them through the fenderwall with some reinforcing plates to spread the load a bit.
I'm sure that whatever you come up with will be fine. Love that streamline tubing.
I'm sure that whatever you come up with will be fine. Love that streamline tubing.
07-12-2019, 07:10 PM
#20
Archive Gatekeeper
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For what it's worth, here's the original design of this strut bar on the Zombie.
07-12-2019, 07:16 PM
#21
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Last edited by Bigfoot928; 05-23-2020 at 03:04 PM.
07-12-2019, 08:29 PM
#23
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Last edited by Bigfoot928; 05-23-2020 at 03:04 PM.
07-13-2019, 04:49 PM
#24
Drifting
hmmmm the car wasnt shipped back to me until 2011 . ........aluminum bar with 90 degree angle welded to reach the stock bolt location.....simple and very effective
Last edited by andy-gts; 07-13-2019 at 11:51 PM.