UPDATE - William posted pictures of the production version of the brace as well as ordering information. See this post .
UPDATE - See William Mapstone's post below for updated info on a production model and pricing info.
Spent some time today making up a bolt in support for the 3-link upper frame mount. The issue was discussed in these posts: Post 1 , Post 2 . I'll post some more details on how the front attachment works (there is more to it than meets the eye) when I get a chance. Also will post some pics of the support out of the car. Note that this is just a mock up and I will use langer bolts for the rear mount. Comments are welcome!
I would also like to purchase one. Mine hasn't moved YET but I've been avoiding spinning my wheels since this problem surfaced. Preventative medicine.
Thanks,
Ron
It seems from the pictures that the new strut is secured to the bracket with the same bolt that is attaching the link. Is the bolt engineered for both loads? Is the bracket that secures the aft end of the strut strong enough for the additional loads? I think not. However, I am looking at only the supplied pictures and can not see the overall picture of the problem. My solution would be to box in the existing link forward mounting braket. That is to weld a metal plates between the two existing vertical mounting brackets. both on the front and back of these brackets, leaving enough space at the back of the bracket for mounting the link, allowing for up and down movement of the link. If possible, extend these new plate up the sides of, and welded to the 2X3 horizonatal cross tubing. A boxed in braket is very hard to twist.
On the forward strut mounting bracket, where you have added the plate with one bolt going through the rod end and a second bolt in the unused lower hole, why not go ahead and make that second bolt a full-length bolt all the way through both sides of the bracket, with a spacer in between the two sides for a little more support?
Oh boy,
Let me play the "bad-guy" part here before we incur Bill's involvement. Rod's not a paying vendor or advertiser.
If one of the current vendors or advertisers was willing to take Rod's mod and market it with Rod as their sub-tier supplier, maybe that would be acceptable. (That's assuming Rod would want to build more of them)
Wow, so I guess you guys like it! Don is right though, I'm not a vendor here so I can't sell them. I would love to become a vendor but I just don't have the time between my real job and trying to get my own car done. I'm my own worst enemy on the latter since I can't seem to stop playing with these ideas.
That having been said, I have approached one of the great vendors here to see if he is interested in manufacturing some of my mods. Totally his decision and if he decides to decline then I will talk to someone else. Whoever it is would have to take over the manufacturing aspect since I just don't have the time. So if you are interested post away and maybe that will pull him over the fence!
I would be interested in purchasing one of the bolt-in support brackets, when they end up in production - price is a key factor for me, simplicity without bells and whistles is best.
Influence point to somebody deciding, and feel free to contact me when pricing is set and they are ready to go.
Bob,
The current bolt is a 5/8" Grade 8 bolt capable of taking 27,000+ lbs in shear. The max loads it should see are in the 3000 to 4000 lb range so I would say the bolt is not the weak link. Also, the bolt is designed to take whatever loads the 3rd link imparts on it. The addition of a brace to the bracket will not result in higher loads than the bolt was designed for. It simply distrubtes them into the frame in a different manner so as to relieve some of the load on the frame bracket. And all is not as it seems for the front connection and I will post details a little later.
As for the rear mount the existing frame mount is very sturdy. On the 3-link it is even cross braced lateraly by the 3-link frame. The primary loads from the support are fore-aft with a slight lateral component. On top of that the bar is there to supply additional support to the front bracket and will not take the full loads. To fail the rear frame bracket you would have to longitudally shear a 6-1/2" weld between the bracket and the frame (to say the least). Not going to happen.
Porxter,
I looked at that but there is not enough clearance to the rod end. If you look at the second last picture you can see there is very little room. I'll post more details in a little while showing how the front joint is stronger than it appears.
Here are some additional pics of the front joint showing the inside details. I wanted to make sure the solution would not affect the ability to use either hole. There isn't enough room between the two holes to allow the use of a second 5/8" bolt since the head of the rod end is in the way. So I got a piece of 5/8" OD x 1/4" ID seamless tube and drilled it out to 5/16" ID (I would have bought it that way if they had it in stock). I cut a length that was just shy of the thickness of the two bracket pieces when sandwiched together. The 5/16" SHCS and over sized washers simply locate the bushing centered in the two brackets. Since the joint is in pure shear when loaded under acceleration the bushing adds substantial strength to the joint. Under braking the joint is primarily in shear, which the bushing takes, with a small tension component, which the bolt takes. But that tension load will be substantially less than the 5/16" bolt's rating at over 8000 lbs.
As you can see this set up retains the flexibility to use either hole for the rod end and the bushing simply goes in the other hole.
The lower part of the rear bracket needs to be notched to clear the support arm. This, plus drilling the second hole for the rear bracket, are the only mods required to the frame.
Excellent work Rod.My non-officially-educated engineering head says this is extremely sound.There is nothing like supporting a load from an angle as close to parallel to the load as this is.You've taken the design of the panhard mounting bracket and applied it to the 3rd link."Elegant simplicity" works real well here.As you may remember,I did mine differently.Wish I'd seen your first cause I'd copy it or buy it in a heartbeat!
Beautiful job and good engineering. One thought though, if someone does go into production with this. Grade 8 bolts are best in tension. For sheer you would ideally use a grade 5, although in this case either is probably strong enough.
I'm glad to see William is willing to jump on this if your first person turns it down.
Jim, seems like I am always in the garage on the weekends. I'll fire you a PM with my number so you can ring me later in the week and we can tie down a visit. Are you back on the road yet?
Cheers, Rod
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