[python] Re: Svar: for August: stearing headset as pivot

Have you considered useing aircraft turn bukle bolts?
  ----- Original Message ----- 
  From: r.mccrady@xxxxxxxxxxx 
  To: python@xxxxxxxxxxxxx 
  Sent: Thursday, March 22, 2007 8:33 PM
  Subject: [python] Re: Svar: for August: stearing headset as pivot


  Mr. hz:

  I went to an automobile parts store looking for suitable rod ends, but they 
weren't able to help me out. They have their computer there, and the first 
thing they want is "what kind of car is it?" Can you recommend a manufacturer, 
distributor, a model number, a source car, or anything like that so I could 
find suitable rod ends, please? Thanks.

  -Rod McCrady
    -------------- Original message -------------- 
    From: "25hz" <25hz@xxxxxxxxxx> 

    > If I understand you correctly, the same thing happened to Marcel's 
python. 
    > Against my "sage" advice (:)) he used a head tube and bearings for his 
    > pivot. The lever force from the front ended up dimpling the bearing races 
    > and "indexing" the steering. It's still rieable just fine, but the subtle 
    > ratchetting is annoying. Higher quality bearing races or headsets might 
    > alleviate this problem, but IMO, you can't beat a couple of 1/2" rod 
ends. 
    > They use these as rod ends on F1 Indy cars, so a good pair on a python 
    > should last a couple decades, minimu :) 
    > 
    > 
    > 
    > > Hey August, 
    > > check the "python for Marc" on Dirk's page: 
    > http://dirkb.dnsalias.net/pythonmarc.html 
    > > He used a steerh ead as pivot. I am considering it too. But I guess 
there 
    > are pros and conts. The axis has a larger diameter, less weight (?) and 
    > would fit very well in my design. I am a little concerned about the 
bearing. 
    > From normal bikes I well know this phenomenon which we call 
Autobahnstellung 
    > "highway position" in german. I guess you know what I mean. 
    > > In the position as a pivot, there is certainly even more weight on the 
    > bearing. 
    > > And honestly, I always had trouble changing the headse once it is worn 
    > out. 'had to use two componant glou as you hardly find the one that fits 
    > exactly. 
    > > 
    > > So it is good you bring up the point. I guess Dirk can say something 
about 
    > it. I keep reading.:-) 
    > > 
    > > cheers 
    > > Thomas 
    > > 
    > > >>> "August" 22-03-2007 17:40 >>> 
    > > I will be tr ying t o build a homemade python soon I,m getting some 
ideas 
    > from 
    > > pics i,v saved some of whice i have included to explain my plans.I have 
    > > some key points that are absolute:1 all aluminum-2 all bolt together 
    > useing 
    > > AN grade hardware-3-16"or 20" wheels.Zero or very minimum welding 
required 
    > > maybe just the headtupe ? does anyone know anyone who has used a 
streering 
    > > headset for the pivot? 
    > > ----- Original Message ----- 
    > > From: "Jürgen Mages" 
    > > To: 
    > > Sent: Thursday, March 22, 2007 3:59 AM 
    > > Subject: [python] Re: Self Centering vs. Wheel Flop 
    > > 
    > > 
    > > > Hej Dirk, 
    > > > 
    > > >> In the model it could be better to do the rear part not as trike 
    > > >> wheels but instead to fix to the ground over a joint (scharnier) 
    > > > > l ocated where normally the rear wheel hub is. That way the bike 
would 
    > > >> not hop around like a mad bull, though the arena scenery is quite 
    > > >> fitting for that. 
    > > > 
    > > > I will make a new model including yours and Stephan's ideas. Sounds 
    > > > good. 
    > > > 
    > > > BTW through the model I realised that it is not the weight of the 
whole 
    > > > front part that favors the wheel flop, but only the weight of the 
part 
    > > > that is NOT rising when the wheel turns. Roughly this is everything 
in 
    > > > front of the line [axle - contact patch]. 
    > > > 
    > > >> I have downloaded the SDK for newton, as it should be possible to 
    > > >> feed the model programmatically and to extract graph material from 
    > > >> that. But I am not sure how much I will be able to play with it. At 
    > > >&g t; the moment I am very busy with my job. :-( 
    > > > 
    > > > There is also ODE (Open Dynamics Engine) which is an open source 
    > > > physics engine, but I have no experience with that. I also tried 
    > > > the Newton SDK, but gave up due to lack of time and C++ skills. 
    > > > 
    > > > Groetjes, 
    > > > Jürgen. 
    > 
    > ============================================================ 
    > 
    > This is the Python Mailinglist 
    > 
    > http://www.freelists.org/list/python 
    > 
    > Listmaster: Jürgen Mages jmages@xxxxxx 
    > 
    > To unsubscribe send an empty mail to 
    > python-request@xxxxxxxxxxxxx 
    > with 'unsubscribe' in the subject field. 
    > 
    > ============================================================ 
    >

Other related posts: