Bending an axle

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Pinewood Daddy
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Re: Bending an axle

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Cut car in half down the middle. Join halves with a piece of continuous hinge on top. Screw a thin bracket on the bottom (fixed on one side, slotted on the other) to allow adjustment. Not precise but easily adjustable.
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Stan Pope
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Re: Bending an axle

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Pinewood Daddy wrote:Cut car in half down the middle. Join halves with a piece of continuous hinge on top. Screw a thin bracket on the bottom (fixed on one side, slotted on the other) to allow adjustment. Not precise but easily adjustable.
Not bad at all, PD! A "hinge" works, but may give you a lot more freedom and flexibility than is necessary.

Also, do you want the front camber to be adjusted when the rear changes? Or should it remain flat. (Think... who started this chain of thought and what assumptions that he might make about the car!
Image)

Then try to make it easier to get small incremental adjustments without the risk of "loosing it."[/img]
Last edited by Stan Pope on Wed Jan 16, 2008 7:35 pm, edited 1 time in total.
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Pinewood Daddy
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Re: Bending an axle

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I think the front should remain flat.

Still thinkin'!! And packing for a camping trip this weekend. My Web 2 and I have been invited to camp with the Troop he wants to cross over to.
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Re: Bending an axle

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How about an off center drilled 1/4" wood/plastic dowel that is about 3/4" long to hold the axle tips? Before camber the wood dowel "Floats". Rotating the wood dowel 180 degrees such that the axle tips are now down to induce camber. Wood dowel can then be held in place with small wood screw.
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Re: Bending an axle

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pwdarchitect wrote:How about an off center drilled 1/4" wood/plastic dowel that is about 3/4" long to hold the axle tips? Before camber the wood dowel "Floats". Rotating the wood dowel 180 degrees such that the axle tips are now down to induce camber. Wood dowel can then be held in place with small wood screw.
That would be cool! I could still shim (or bend) the axle to get dead on. But I don't know exactly how much camber will be needed and, if I did know, I probably could not drill that precisely. Still, it might work for you!
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Re: Bending an axle

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Pinewood Daddy wrote:Cut car in half down the middle. Join halves with a piece of continuous hinge on top. Screw a thin bracket on the bottom (fixed on one side, slotted on the other) to allow adjustment. Not precise but easily adjustable.
To continue with the above. What if the hinge were replaced with a lighter weight, but strong material eg nylon fabric or something similar, for purpose of weight reduction, and a precisely cut strip of wood (determine by degree of desired cant) placed and glued in bottom of seam. Not really adjustable but certainly solid.

I also imagine the latch could be replaced by two screws, front and back for adjustment.
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Re: Bending an axle

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doct1010 wrote:
Pinewood Daddy wrote:Cut car in half down the middle. Join halves with a piece of continuous hinge on top. Screw a thin bracket on the bottom (fixed on one side, slotted on the other) to allow adjustment. Not precise but easily adjustable.
To continue with the above. What if the hinge were replaced with a lighter weight, but strong material eg nylon fabric or something similar, for purpose of weight reduction, and a precisely cut strip of wood (determine by degree of desired cant) placed and glued in bottom of seam. Not really adjustable but certainly solid.

I also imagine the latch could be replaced by two screws, front and back for adjustment.
Okay ... now for the big question:

Does the amount of camber depend on how far the wedge is pushed into the gap? And, if so, must it be "pushed?" Might it be ...?
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Re: Bending an axle

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Stan Pope wrote: Okay ... now for the big question:

Does the amount of camber depend on how far the wedge is pushed into the gap? And, if so, must it be "pushed?" Might it be ...?
I guess it could. In my senario the wedge, or prcisely cut strip, is cut to a predetermined thickness based on Stan's calculations. :D Then glued in place.

Might it be pulled?
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Re: Bending an axle

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doct1010 wrote:
Stan Pope wrote: Okay ... now for the big question:

Does the amount of camber depend on how far the wedge is pushed into the gap? And, if so, must it be "pushed?" Might it be ...?
I guess it could. In my senario the wedge, or prcisely cut strip, is cut to a predetermined thickness based on Stan's calculations. :D Then glued in place.

Might it be pulled?
That was the missing word, but it seems that those questions didn't do any good! :(

It might still cause some lights to go on though ... I think I'll let it simmer for a while longer. :)
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Re: Bending an axle

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I have a few questions of my own. Does the gap left by the saw kerf matter or come into play in some way? How important is the adjustability, ie does it need to be dialed in or can one work from a static start with the camber predetermined? I would assume for purpose of alingment you would NOT want to start with axles canted, for reasons you have articulated elsewhere. If not my shim method with pro axle tool is far easier. :D

My last stab for tonight. Assuming the wedge is pushed into gap, I would say yes the camber is clearly dependant on how far it is inserted.

If it were to be pulled I can imagine two parallel grooves, wider at the top opposing each other one front and back with a small triangular wedge in each. A tug on tail of wedge widens gap. You would probably need to wrap it with rubber bands to keep wedges in place for tests then glue it all up.
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Re: Bending an axle

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doct1010 wrote:I have a few questions of my own. Does the gap left by the saw kerf matter or come into play in some way? How important is the adjustability, ie does it need to be dialed in or can one work from a static start with the camber predetermined? I would assume for purpose of alingment you would NOT want to start with axles canted, for reasons you have articulated elsewhere. If not my shim method with pro axle tool is far easier. :D
For me, the adjustability is necessary, because I don't know exactly what the target angle is, and, if I did, I doubt if I could cut it precisely enough.

If you had a kerf, then you would have to do something to keep the original separation at the top (I think). and it would have to be stiff enough (rusted hinge?) so that the initial alignment could be done. How might you avoid needing the rubber band to hold the wedge in and to keep the wedge in control of the camber angles?
doct1010 wrote:My last stab for tonight. Assuming the wedge is pushed into gap, I would say yes the camber is clearly dependant on how far it is inserted.

If it were to be pulled I can imagine two parallel grooves, wider at the top opposing each other one front and back with a small triangular wedge in each. A tug on tail of wedge widens gap. You would probably need to wrap it with rubber bands to keep wedges in place for tests then glue it all up.
Is that the best approach direction? Maybe you are making it too complicated ... But, yes, need to hold things together sufficiently well that the adjustments will survive a few timing runs. And we would like to be able to pull the wedge in by short, measured amounts until run times start to deteriorate. And then we can diddle the RR toe some more ... etc :)

Last question ... maybe: What are the relevant differences between a 4-40 NUT and a WEDGE?
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Re: Bending an axle

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Stan Pope wrote:Last question ... maybe: What are the relevant differences between a 4-40 NUT and a WEDGE?
OK. Embed the nut in the wedge and use a screw to adjust the depth of the wedge. The wedge would be inserted in a saw kerf (not through) in the bottom of the rear section of the car. The side rails would act as torsion bars, pushing the rear section back to normal.

Getting back to your question: a 4-40 nut has a thread pitch of .025, so turning a screw 1 turn would adjust a .025 distance. A Wedge is one of the basic Simple Machines. A Screw is an Inclined Planed wrapped around a diameter. The screw has a larger mechanical advantage.
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Re: Bending an axle

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Aah. That's what its called. A4-40 nut. I was thinking along those lines last night but could only come with thumb screw, feft it would be misleading and did not know how to explain in technical terms.
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Re: Bending an axle

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What's up Doc?? Let's keep this going!!!
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Re: Bending an axle

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I think I have a good mental picture now, kinda what I hinted at above with the two screw method suggested. Thanks Pdad for the tech explanation of the the 4-40 screw.

I still have some problems with the gap left by the saw kerf. I assume you cut the block after you have drilled your axle holes perfectly straight. The "rusted hinge" is then applied to top of car. At this point are we not introducing some variance and a variable that is dependant on the skills of the builder? Two things come to mind, one is maintaining the proper gap and at same time keeping two halves level and in same plane.
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