[ATM] Friction and sticking in multipoint mounts

[artbianconi@blast.net]

I have disassemble three multi-point suspension systems, removed 
the fulcrums, placed them all together on a common shaft, aligned 
one side (where possible) and then looked closely at the nested 
parts. No two were the same!

Making identical parts individually will cause that every time.

Best to drill three holes (the central pivot and those on either 
side) in al the fulcrums, slide them all together onto a close 
fitted shaft, clamp them in a machinists vice and then mill them 
all at the same time. 

There will likely still be some geometry that lacks symmetry but 
the error will be constant from one part to the next. Good news 
is that if you are working with a soft material (aluminum) you 
can use a flat file to get a similar result.

Use a teflon, Delrin or some other self lubricating insert in all 
the pivots and the friction problems will likely have been 
minimized some. They won't all be gone but they'll be reduced.

Part of the trick is to create uniformity in every part of the 
linkage systems. Mass, C of F, moments, etc.

Good luck!

Art

>When I showed them a typical 27 point mount and tell them what 
>is expected, they roll their eyes. They hear ". . . to 1/12th
>wave accuracy"  and they look at me as if I am crazy!

>There HAS to be a better way!

Jerry B. Hillman responded:

"Funny,  When I showed my 27 point mount to a mechanical 
engineer, I got the same reaction. Of course, mine was fabricated 
with a hacksaw and a drill press.

Clear skies, Jerry


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