Suspension String Computer-- Now up and running

Discussion in 'Chassis' started by 1.8T_mk2, Sep 16, 2011.

  1. 1.8T_mk2

    1.8T_mk2 Paid Member Paid Member

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    Just been reading a bit in Competition Car Suspension about making your own suspension string computer and wondered if anyone had tried this? Or is there an eaiser electronic solution?
     
    Last edited: Dec 9, 2011
  2. A.N. Other Banned after significant club disruption Dec 5th 2

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  3. 1.8T_mk2

    1.8T_mk2 Paid Member Paid Member

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    Not quite Chris. It is a basic mock up of the front suspension in either ply-wood or cardboard then you use string to determin the roll center. You can then move the wheel through either bump or compression and track the movement / angles / geometry. Then you can simply move the string to see what changing different components ( wishbone length / mounting points / wheel offset ect ) will do to the suspension with out the need for making / changing parts on the car only to find your no better off. Is accurate to about 1-2mm apparently.

    I'll try and sort out a picture...
     
  4. mec82 Forum Member

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    Can use a 3D CAD package, solidworks,catia etc.

    Although if you cant use that software already then a physical mockup would be easier than learning CAD.
     
  5. A.N. Other Banned after significant club disruption Dec 5th 2

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    Sounds intriguing - look forward to pics of this :)
     
  6. prof Forum Addict

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    that book should be read by everyone who fiddles with cars,
     
  7. Crispy 8V CGTI Committee - Club Secretary Admin

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    it is a amazing book had it at least 5 years - read many a time!
    I have most of my measurments ready to make one, just one of those things I keep getting round to doing on these winter months
     
  8. 1.8T_mk2

    1.8T_mk2 Paid Member Paid Member

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    Right I'm back on this now... Collecting dimensions / measurements at the mo so should hopefully get a fully working model in the next week or so.

    Just out of curiosity what measurments did you take Crispy? I got about a page full already.
     
  9. 1.8T_mk2

    1.8T_mk2 Paid Member Paid Member

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    Ok, I have taken all the dimensions needed for the string computer and will hopefully get it sorted by the weekend.

    This is what I will be making:-
    [​IMG]
     
  10. 1.8T_mk2

    1.8T_mk2 Paid Member Paid Member

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    I do have autocad but I'm not that experienced with it so takes me ages to do anything but I've got a feeling it will be easier to read the results from the string computer. It may look a little Blue Peter but it is supposed to work really well.
     
  11. A.N. Other Banned after significant club disruption Dec 5th 2

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    So this is an off-car model designed to replicate pick up points, with a scale behind it to observe changes?
     
  12. 1.8T_mk2

    1.8T_mk2 Paid Member Paid Member

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    :thumbup: Correct, it allows you to plot the roll center through roll, bump and rebound.

    I thought I had enough hardboad to make one but still need to get down to B&Q to get a bit more. Will have it done by the this time next week.
     
  13. A.N. Other Banned after significant club disruption Dec 5th 2

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    Wow! What scale would you use though? 100% to keep it simple?
     
  14. 1.8T_mk2

    1.8T_mk2 Paid Member Paid Member

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    Not sure on the scale yet. I've drawn the front suspension in 10th scale and have calculated that the swing axle length is just under 10 meters. If I use 100% I'm going to be needing a lot of string! :lol:
     
  15. 1.8T_mk2

    1.8T_mk2 Paid Member Paid Member

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    I now have the much needed wood to make this thing and see if it's all it's cracked up to be.
     
  16. 1.8T_mk2

    1.8T_mk2 Paid Member Paid Member

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