George Lendich wrote:

Those stiffeners finishing at the face should they have a curved edge as

compared to an abrupt square edge - I'd prefer the

curved finish for aesthetics but don't know about the best approach for

stress transfer.

George (down under)

Looking good George. Carry them around the bottom flat face where

possible.

The square edge will mate nicely with Tracy's psru. You will need maybe a
5 mm radius just so it pulls from the sand cleanly. When assembled it will

look great.

You are a pretty good pattern maker.

Paul Lamar

Thanks for the encouragement, I need it, I'm getting to the real tedious/
critical bits.
I used your Perspex idea and found my original bolt pattern was out a
little - measure twice cut once !!
at this point.

So just to clarify --- the stiffener as shown is too rounded, you would like
it sharper to match Tracy's PSRU - about 5mm at the corners - OK !!

You will notice the starter pattern lower bottom left of pictures.

George (down under)

No pic attached George.

Paul Lamar,

Sorry Paul,
Trying to avoid sending the same photos again and again.

Your drawings display the stiffeners as round at the top and squarish at the face centre, as this attached picture shows.
However I'm not quite sure exactly this is how you want them. I just feel if it's too square at the top corner, they will look
too large i.e. 30mm to 20mm to 10mm.

It may be the small radius you speak about is for the ones which terminate at the sides (engine mount areas).

Just a tad confused on this issue, but want it to look right too.
George (down under)

We got that one. Here it is again. The stiffeners look fine and of the right
size. One can always cut them down if one wants to live dangerously :)

BTW you can use a hole saw to cut large holes between the stiffeners if
you need to inspect the guts.

Paul Lamar
 
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