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  • #46
    Originally posted by rukman View Post
    Perhaps the guy who did Gustave's work would be more amiable if he knew he could make a run of 10 sets?
    Remember though, for Gustave he basically scratch built the trailing arms from tubular steel. That is far more than I need/want done. For what I am visualizing, he would probably need a new plan and new tooling.

    I really wasn't feeling that he wanted to be involved in this sort of thing anymore.

    There is a good fabricator at Infineon I am going to ask next. It really should not be too huge of a job. The outside pivot needs to be machined down and the adjustment mechanism welding on in the right place. For the inner one, I plan to use a spherical bearing. All that should be needed there is to machine appropriate sized sleeves and/or axles to fit the bearing in the stock bushing housing.

    I am going to a junkyard tomorrow to get a couple of trailing arms. That should help visualize things.

    I don't know if any of you have ever used Emachine. I think the idea is great in principle, I just wish the pricing was a bit more reasonable and the delivery time a bit quicker. I particularly like their drafting software. I am sure it cannot do a tenth of what Solidworks can, but it is much easier to use and rather than costing $7K, it is free. Unfortunately it can only be used for Emachine purchases. They are just too dang slow and expensive though. Too bad..... Their quotes for fairly simple machine jobs are usually two or three times what my local shop charges.


    - - - - - - - - - - - - - - - - - - - - - - - - - AUTOMERGED! There's no thread "bumping" or "double posting" within a 24hr period. - - - - - - - - - - - - - - - - - - - - - - -


    Originally posted by UweM3 View Post
    what I have done so far:





    Idea was to leave the internal joint of the trailing arm as is (with a spherical bearing maybe) and weld this on the outside pickup.

    Pink screw for camber ajustment, lilac for toe. I didn't spend too much time so the bolt length etc isn't really finished. If somebody can spec a rod end suitable I will try and keep working on it over winter. Doesn't need to be metric, I had a quick look and imperial roadends seem to have better load values than normal metric thread.

    Uwe,

    What software do you use to draw this stuff up? I know Solidworks is the typical answer, but it costs something like $7K.....I cannot believe anyone actually buys it......

    What am I missing?
    Last edited by Ironhead; 08-24-2008, 03:41 PM. Reason: Automerged Doublepost

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    • #47
      Just a thought here Mr Ironhead
      This is something that I am keen on looking at also. It was something that was going to be "down the track" but here is a method I used on an old Datsun 1600 (P510) FJ20T powered race car I owned quite a few years ago.
      Allot of people use the rose-joint on the trailing arm mount for adjustment. But as said above it's a PITA to have to remove to adjust etc. What I did to rectify this problem was to use a right and left hand "nut" in the middle section between the rose-joint and the trailing arm. It worked like a turnbuckle arrangement using lock nuts at each side. With a fixed LH thread on the modified trailing arm and a RH thread rose-joint attaching to the sub-frame. If it is calculated correctly you can get sufficient movement for a good range of adjustment.
      It didn't however sort out the issue of camber adjustment.
      I got a high tensile LH thread 7/8"UNF bolt and TIG welded it to the backside of a matching nut that I had welded onto a plate that attached to the cut off trailing arm. I wanted to avoid welding on the front face of the thread as it obviously weakens that section. Being a machinist I made my own left and right handed centre section using 30mm hex and turned down some standard nuts to use as lock-nuts. The rose-joint just attached to the existing mount. Now whether this is something that can be done on our trailing arms in another issue. It looks like there may not be enough length to cut off to get the mechanism in there.
      Anyway, this is just my experience and I wanted to pass it on.

      Attached is a really crap sketch of what I mean. I wish I had taken pics of this when I owned the car.

      Cheers
      Aaron
      PS.... It never broke so that's a good thing


      "But most of all...
      ... I like the way you move......"

      Comment


      • #48
        Originally posted by Az in Oz View Post
        Just a thought here Mr Ironhead
        This is something that I am keen on looking at also. It was something that was going to be "down the track" but here is a method I used on an old Datsun 1600 (P510) FJ20T powered race car I owned quite a few years ago.
        Allot of people use the rose-joint on the trailing arm mount for adjustment. But as said above it's a PITA to have to remove to adjust etc. What I did to rectify this problem was to use a right and left hand "nut" in the middle section between the rose-joint and the trailing arm. It worked like a turnbuckle arrangement using lock nuts at each side. With a fixed LH thread on the modified trailing arm and a RH thread rose-joint attaching to the sub-frame. If it is calculated correctly you can get sufficient movement for a good range of adjustment.
        It didn't however sort out the issue of camber adjustment.
        I got a high tensile LH thread 7/8"UNF bolt and TIG welded it to the backside of a matching nut that I had welded onto a plate that attached to the cut off trailing arm. I wanted to avoid welding on the front face of the thread as it obviously weakens that section. Being a machinist I made my own left and right handed centre section using 30mm hex and turned down some standard nuts to use as lock-nuts. The rose-joint just attached to the existing mount. Now whether this is something that can be done on our trailing arms in another issue. It looks like there may not be enough length to cut off to get the mechanism in there.
        Anyway, this is just my experience and I wanted to pass it on.

        Attached is a really crap sketch of what I mean. I wish I had taken pics of this when I owned the car.

        Cheers
        Aaron
        PS.... It never broke so that's a good thing



        I actually thought about doing something like that, but the concerns you bring up are the same ones I had. You would have to cut the trailing arm way back to make room for that setup....

        But my biggest concern would be the length of the leverage working against the threads furthest from the bearing. Like you said.....it didn't break.....so who knows?

        Comment


        • #49
          Originally posted by Ironhead View Post

          Uwe,

          What software do you use to draw this stuff up? I know Solidworks is the typical answer, but it costs something like $7K.....I cannot believe anyone actually buys it......

          What am I missing?
          cough, cough erm I bought it...... I earn my money with Solidworks.
          It's not only the initial purchase price, you have to pay 1.5$k per year for support and updates. (in europe, I think in the US it's cheaper)


          Goodbye M3, you served me well.

          Comment


          • #50
            Here's what I made for my car. (bushings is in just for the jig, is spherical bearing in there now)
            Photobucket

            Photobucket

            Photobucket
            Last edited by Turbo ///M3; 08-25-2008, 12:36 AM.

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            • #51
              Yup....that's precisely what I have in mind.....

              Did you design and fab all of it, or is anything available "off the shelf"?

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              • #52
                Made everything myself, have parts to make a few more.

                Comment


                • #53
                  Originally posted by Ironhead View Post
                  Hey dudes......

                  I am trying to figure out a source for these thingys. (thanks Booker for the pics I "borrowed") They are used on the DTM trailing arms to allow a rod end to adjust for camber and toe without being unbolted and "turned".

                  Does anyone know if they are a BMW Motorsport specific part, or a generic item used in other motorsport venues?

                  Thanks!





                  I too am keenly interested in a solution to this problem. I know Booker and have seen his solution which is working fine in his car. I'll contact him and see if he's interested in making some up.


                  Originally posted by UweM3 View Post
                  what I have done so far:





                  Idea was to leave the internal joint of the trailing arm as is (with a spherical bearing maybe) and weld this on the outside pickup.

                  Pink screw for camber ajustment, lilac for toe. I didn't spend too much time so the bolt length etc isn't really finished. If somebody can spec a rod end suitable I will try and keep working on it over winter. Doesn't need to be metric, I had a quick look and imperial roadends seem to have better load values than normal metric thread.

                  Uwe, yours looks awesome too!! I'm on-board with you if you finish the design and market it!! Looks awesome!! Did you spec it using measurements from MS parts?

                  Gustave's setup is wicked neat, but, it has no attachment points for rear bar, and AFAIK, has never been fitted up to a car, tested or used. The guy who made it up is a bit cantankerous and probably way too expensive.

                  Turbo-Man, yours is excellent too! Ready to make some up???

                  I'm with Ironhead on this and want a simpler solution. Bookers, Uwe's an TurboM3's seem the best. Lets kick it up a notch... winter is coming and that's the only time I can do a project like this...
                  Last edited by Ron ///Man; 08-25-2008, 02:07 AM. Reason: Incomplete post...
                  Ron ///Man

                  • '91 Gr-A Former CiBiEmme / Ravaglia - Sold
                  • '90 M3 Faux EVOII Alpineweiss 36K Orig Owner - The Queen
                  • '91 M3 Faux EVO III Brilliantrot Euro Driveline - The Rocket
                  • '91 M3 Faux Gr-A Club Racer DM - The Alter EGO
                  • '89 M3 M3T / ITR Club Racer
                  • '94 Spec E36 - Eh....
                  • '09 M3 - Tarmac Terrorist
                  • '04 330Xi Sport 6 Speed - Snowmobile
                  • '07 530 Xi - Highway Star
                  • http://www.imwcarparts.com/e30-m3-parts.htm


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                  • #54
                    While I don't have the fabrication skills myself, I'm interested as a winter project if someone decides to make a couple sets of these.

                    Subscribing.
                    sigpic
                    Track Car Build | COM Sports Car Club

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                    • #55
                      It's no problem for me to make some more since I have the jig, and all the parts to weld on the trailing arms. Mine are made for coilovers, but I can make DTM "light" without one tube, so you can use std springs.

                      Mine is also made for M5 hubs and driveshafts, so the shockmounts have been relocated.

                      Guess they would be approx $2000

                      And for those of you planning to make your own, it's a lot of work!

                      Comment


                      • #56
                        Originally posted by Turbo ///M3 View Post
                        It's no problem for me to make some more since I have the jig, and all the parts to weld on the trailing arms. Mine are made for coilovers, but I can make DTM "light" without one tube, so you can use std springs.

                        Mine is also made for M5 hubs and driveshafts, so the shockmounts have been relocated.

                        Guess they would be approx $2000

                        And for those of you planning to make your own, it's a lot of work!

                        I think this sounds great. Yours are exactly what I am looking for.

                        The only problem is that I am in the USA and you are not. Shipping a pair of trailing arms to you, then you shipping them back.....would certainly be pricey.

                        Are you interested in cranking out a supply of the camber/toe adjustment mechanisms and selling those individually? I presume making those was the trickiest part of the job?

                        I am also interested in your front arms. Since they are apparently entirely fabbed up, are you interested in selling some of those? What subframe mods are necessary to install them?

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                        • #57
                          Shipping to usa is no problem, and I don't need your old arms, I have stock trailing arms, mediablasted ready for fabrication. They will be painted and pre calibrated ready for install.

                          The fronts will be much cheaper, subframe needs to be made like the DTM one, have templates, so it's easy for you to make. will post pics later, and the rear mount is included.

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                          • #58
                            Originally posted by Turbo ///M3 View Post
                            Here's what I made for my car. (bushings is in just for the jig, is spherical bearing in there now)
                            Photobucket
                            Now that is a sweet looking setup! Respect.
                            Do you mind telling me what rod ends do you use? I do understand if you don't want to disclose this, no worries.

                            The biggest cost for me is the CNC milling of the "body" out of one pice (the green part in my 3D model). I was hoping to make it in two parts and weld it.
                            Last edited by UweM3; 08-25-2008, 05:45 AM.


                            Goodbye M3, you served me well.

                            Comment


                            • #59
                              Ironhead; here's some pics of the front setup, sorry for bad quality pics.

                              Photobucket

                              Photobucket

                              Photobucket

                              I use QA1 rod ends and spherical bearings.

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                              • #60
                                I'm definitely interested.

                                Mike

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