T-Bar Delete with Roll Center correction and Rod ends. COMPLETE!
07-23-2012, 01:15 PM
#16
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Interesting project... looks nice...
Did you do any FEA or stress analysis on the cad designs, AND did you direct port the CAD or are you using a secondary software package to generate the CAM files (assuming G-Code, but I could be wrong).
I would be interested to see an FEA done, also interested in the quality standards you are working under (I am at heart a QE, but work with PTC Creo almost daily, have worked in everything from a lab to a FAB Factory, and lately have been doing more and more FEA using PTC Simulate and ANSYS)...
On a related topic.... if going to this extreme... why not totally redesign the rear end to eliminate the short comings of the trailing arm design? (OR are you guys required by class to maintain the rear end trailing arms the cars were origionally delivered with?
Did you do any FEA or stress analysis on the cad designs, AND did you direct port the CAD or are you using a secondary software package to generate the CAM files (assuming G-Code, but I could be wrong).
I would be interested to see an FEA done, also interested in the quality standards you are working under (I am at heart a QE, but work with PTC Creo almost daily, have worked in everything from a lab to a FAB Factory, and lately have been doing more and more FEA using PTC Simulate and ANSYS)...
On a related topic.... if going to this extreme... why not totally redesign the rear end to eliminate the short comings of the trailing arm design? (OR are you guys required by class to maintain the rear end trailing arms the cars were origionally delivered with?
No, no FEA simulations. No need. It's extremely overbuilt. If you would like to run one for me, I would be more than happy to share specifications with you on material type, sizes and thickness, so that you could run one! Extremely confident it is above and beyond. NOT that I have solely relied on the fact that pretty much everything I've done material wise, matches or exceeds that of the Kokeln unit, but it is a proven item. Of course many other facts and experiences drove my material and design choices for the build. Admittedly, sometimes I weld in haste on some items and don't do all the necessary cleaning and beveling of materials on items such as a catch can.
Not on this guy. I made sure to take every proper step when doing each and every weld. All bevels, cleaning, and proper fitments were given highest priority, and in a few cases, back gassed. I made sure the tungsten thickness was matched to material, and wiped clean the rod before every pass. (ER70S-2 rod, and sometimes -6. In my case, Size dependent) I used some stainless rod when welding mild steel to chromoly where consistent ductility wasn't structurally important.
Lastly, this piece is as simple a design as you can get without having to just go to extremes where I would need the whole car to modify, or do something like Duke has done with his Boxster suspension. All other options at least double in complexity and cost to this simple bolt in Bar. More like triple and quadruple. In conclusion, to change the suspension much more than this, It's a diminishing return sort of thing.
Last edited by 95ONE; 07-24-2012 at 01:50 AM.
07-23-2012, 04:31 PM
#18
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07-24-2012, 12:07 AM
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07-24-2012, 12:55 AM
#23
Drifting
Looks great. I have a buddy who wants one and I need to see if you can make me just the spring plates to go with my Kokeln setup - my aluminum spring plates got messed up. I'll PM you.
07-24-2012, 01:34 AM
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There are some rules on the forum, but it seems there is still a need for these guys, So I think my next statement is o.k.
Please PM me.
Skip, I can certainly get you some spring plates with turn buckle rod ends. As long as the Rod ends you have are 5/8", no problem. I will also need a few detailed pics of the Kokeln Spring plate to know what kind of offset they may or may not have from the centerline of the Rod End. The length on the other hand SHOULD be same as stock, but it wouldn't hurt to verify. I'll look for the PM.
Please PM me.
Skip, I can certainly get you some spring plates with turn buckle rod ends. As long as the Rod ends you have are 5/8", no problem. I will also need a few detailed pics of the Kokeln Spring plate to know what kind of offset they may or may not have from the centerline of the Rod End. The length on the other hand SHOULD be same as stock, but it wouldn't hurt to verify. I'll look for the PM.
Last edited by 95ONE; 07-24-2012 at 01:53 AM.
07-24-2012, 01:45 AM
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I'm sorry John, I never answered this question. We start with a horrible CAD program called Turbo Cad. It kills me. It has so many weird quirks. I'm used to AUTOCAD 2010. From there we use a secondary Software program called Sheet Cam. - G code. - So, you sir, are correct.
07-24-2012, 02:37 AM
#26
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Nice job. It looks great. If I wasn't getting one from Vision as a favor, I'd be in line.
Everybody who is a real racer should start the line here.
TonyG
Everybody who is a real racer should start the line here.
TonyG
07-24-2012, 08:53 AM
#27
Three Wheelin'
As a Kokeln rear suspension owner, it is the no compromise way to go for racing. It allows you to micro adjust the toe in seconds (after you set up the rack, strings etc.).
07-24-2012, 12:34 PM
#28
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Nice work !
Have you removed the rod-end bolts with the end support in place yet ?
On my Kolken setup I had to remove about 1/4 " of material at the top of the opening in the end bracket
Have you removed the rod-end bolts with the end support in place yet ?
On my Kolken setup I had to remove about 1/4 " of material at the top of the opening in the end bracket
07-24-2012, 12:44 PM
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Yes sir. They come out. The top of the bolt just touches the top of the end support torsion hole, but spins and comes out with a little bit of wrestling, but not bad. Not sure why you would need them to come out much though. I suggest using loktite every time.
07-09-2013, 11:26 PM
#30
Burning Brakes
Well not so good...
Guys, I certainly appreciate all the ingenuity and effort here, but this is a good example of the need for true R&D when tackling a project of this magnitude. My torsion tube bent under the second weekend of racing.