Due to very tight budget with my first "new" car purchase and the abilty to design parts in 3D + having a mini machine shop at work created this.







This is the "prototype" I wanted to do a fit/design check before I spend more time on detailing the bars. Simple design, all my measurements were correct so both bars were installed in under 5 minutes. I havn't had a chance to do a stress test in my 3D software but I'm sure flexing is minimal. Bars are made of T6061 billet alum. Front bar is .75" thick and the rear is .50" thick. I'm sure I can make the rear stiffer with the matching thickness as fronts. I was origanlly worried about the front because when the idea came to me, I really didn't look at the mounts, I was concerned that mounting it only to one point would put more stress on that mount, but after looking at the mount, I noticed there was a spacer plate that linked all three mounts together so all mounts flex at the same rate.

Test drive shows that the stock tires suck. I can hear the tire loosing contact, but yet hold a predictable line. This enough shows that the bars are serving their purpose. I will do a mini canyon run by my work for more testing under stress.

Parts were designed in about 10 minutes for both (with machining drawings) and fab took about 30 minutes for the rear bar and less then 10 for the front bar. We had to mill the .75" thick alum down to .50" over the spane of 43"x 1.5" wide. Best part was the price :D

 

Good work considering the quick design and fab time. What software did you use?

 

thanks

I use Solidworks

 

its nice and shiny

 

good work, but shouldn't the front be connected to at least 2 of the bolts to actually stablize the strut?

 

wow thats pretty nice, i do some machine work too and i plan on changin the hollow strut on mine with a solid bar but i plan on keeping the mounting brackets cause they connect to 3 bolts. i think 1 bolt might be a bit much stress on one point

 

Yes, that was what I was worried about when I wanted to use the same design from the rear to the front. But looking at the stock strut mount, there is a plate added on top of the strut mounts that links all three mounting studs together. So added the bar to one stud will actually share some of it load to the other 2 studs because of that plate. I don't have the front of the car modeled so I can't do stress test of the theory. I have most of the rear modeled up so I should conduct some testing soon.

 

^^Not necessarliy, th plate does little to nothing, the one bolt set up creates a lot of stress on that one bolt, which could cause it to wear and stip, possibly break, with 2-3 bolt set up it evenly distributes the load bearing onto the 2 or 3 bolts, 3 for optimal performance, which allows for much less wear, if any

now i am not not knocking your work, just trying to help you get the best for your time and effort

 

true, I under stand that all the load is on one bolt, I knew these going into that type of design. Does it work yes, will it last I'm not sure. You can sorta fight that for the rear bar since there's only one mount stud for the entire assembly. But the load bearing isn't as hard as the fronts. I need to model the front end and I can do a stress test on the model and esitmate where the weakness is and now much force it will take to break the model. I'm sure that stud will be the failure point, but at what type of force? I'm not sure what grade stude those are so it will hard to set a hardness to the unknown.

 

I haven't had the opportunity to play with Solidworks, but I have been using AutoCAD and Architectural Desktop for over 10 years. You should see some of the stuff I have had to model using simple 3D solids or faces in AutoCAD.

Did you start out with rectangular stock and then just cut it to length and machine then ends down? Or was this started from a much larger block and machined down?

My novice recommendations are as follows.

First, if you can design and end plate that attached to at least two of the three strut mount bolts. This may require you to machine the front bar in three pieces and weld them together.

If that isn't an option, at the very least I would machine gussets into the bar. Essentially leave a triangular shape of material perpendicular to your mounting surface at each side of the bar for strength. If you did this I would also round off the end of the bar.

You can also consider machining the bars into an I-Beam shape or even machining holes into the bar to reduce weight without really sacrificing strength.

At the very least I would look at putting a radius on all of the edges just to clean up the appearance a little.

Nice start though.

 

I used autocad from high school and the first 2 yrs on the job here then we were paid to get trained on Solidworks and havn't looked back since. I design rackmount computer and test stations for Qualcomm, Nokia and our armed forces. Most of the assembles I design over well over 100 parts, so lining up all the parts in CAD takes time and alot of math. In SW, the process is alot easier and you can see there problem areas are faster and easier.

The bar was just some milled down stock, bar was 1.5" x .75" x 12ft when I got it. I just cut it down to length and worked from there. On the rear bar, we milled off .25" to get the thickness down to .50". I dont know how to weld alum nor have a tig welder. I have a wirefeed mig welder I used few years ago to make intercooler pipes and exhuast for my DSM when I had them. I'm going to looking to making a three piece design, using steel mounts then thread it into the alum bar with some fat grade 10 bolt. Then again I can always buy one, but what fun is that? HAHA

This was a fit/function test, I didnt want to pour hours into making a part look pretty if it doesn't work in the first place. I plan to reduce weight off the bars and some crazy eching.