FT: Frame (Twin) FT5 Pivot Bearing Plate

A_HRD

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VOC Member
Has anyone ever manufactured the FT5 Pivot Bearing Plate in Al Alloy (say Dural/7075)?
Or is everyone concerned about the inevitable high stresses in this component leading to (catastrophic) failure?

Peter B
 

Bill Thomas

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VOC Member
Hello Peter, I thought we all did it ?, I have been doing it since 1970, It was one of the first things I changed,
Saving weight !, Don't know what type, Just a bit of alloy, Did the same thing with the front Prop Stand plates.
And pillion plates.
Cheers Bill.
 

Robert Watson

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VOC Member
I don't see an issue
tensile - 7075 t6 74-78K -- C1020 carbon steel 57 - 61k

Yield -- 7075 t6 63-69K -- C1020 carbon steel 42 - 50k

Elongation at break 7075 t6 + or - about 8% C1020 15%
 

timetraveller

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VOC Member
I could organise this if there is enough interest. Two things to note. First is that it would make life much easier if someone has an accurate drawing. I emphasise the accurate as I recently had some parts made and the 'official' drawing had a serious error on it. Secondly the firm who do the laser and water jet cutting have a minimum order of £50. That would be the same for one, or possibly, up to five or ten. They could be made of 7075 ali or even some from stainless steel for those who like shiny bits.
 

highbury731

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VOC Member
G50 is 5/16" dural, and subject to chain load, not supported by a casting
FT5 is 1/4" steel, no chain load, and supported by the primary chaincase

If there is a concern about strength, surely it lies with G50, not FT5

I was toying with the idea of buying a piece of dural plate and drilling through it. Cut from an accurate drawing would be much better.

Paul
 
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Bill Thomas

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VOC Member
G50 is 5/16" dural, and subject to chain load, not supported by a casting
FT5 is 1/4" steel, no chain load, and supported by the primary chaincase

If there is a concern about strength, surely it lies with G50, not FT5

I was toying with the idea of buying a piece of dural plate and drilling through it. Cut from an accurate drawing would be much better.

Paul
I found it easy to clamp the old FT5 to a bit of alloy, And drill through, Same with the prop stand plates.
Cheers Bill.
 

Bill Thomas

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VOC Member
I even used alloy plate for a "D" type stand fittings, Thought I might be pushing my luck, But after a bit of bedding in !,
They have been on there for some years now.
 

timetraveller

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VOC Member
Dear Confused of Thirroul, no need for confusion I had an enquiry about a week ago from a member asking did I know of anyone who had, or who had made, aluminium FT5s. Then a day or so later there was a similar question on this forum. I have recently been getting parts either laser cut or water jetted out for some jobs, some motorcycling and some astronomical so I pointed out that given a drawing it would be cheap and quick to get parts made. The problem is a minimum charge of £50 so there needs to be some interest from several people. That is all. I don't mind getting it organised and posting them off but I will not be getting a batch made to sit on the shelf here.
 
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