Well I am still a wee bit uncomfortable with NO reinforcement.
How about just a couple of .065" thick 4130 straps 1/4 inch
wide laid flat? Skip welded every one inch with a 1/4 inch
long weld.


Paul Lamar

You are the engineer.   I felt it passed the load test o.k. without
reinforcement. But welding a little strip on each side is not a
problem if it will really strengthen the beam so let's do it.  There
may be a problem finding such a strip.  I would not be surprised if
it comes off the shear looking like spaghetti. Not available in the
ACS catalogue.  Cold Roll might be available in that size.   Would
that be acceptable?   Jerry
I think shearing it will be OK Jerry. It is thin enough to twist
back into shape. You can also clamp it down to the beam.
Mild steel might be OK because I am mainly worried about
local buckling or local crippling to use a high tech term.
Paul Lamar

What about a piece of 3/16" rod ?

John

Good idea make it 1/4 inch and I would feel pretty good.

Paul Lamar

Are  you saying that .250 dia.  mild steel rod will be
acceptable?  .   What length?    Jerry

About an inch longer on each end than the slot.

Paul Lamar

Hi Paul and Jerry,
If this part of the beam is in compression, and has not failed, what do
you hope to achieve by adding more metal?
Following with interest, Dave McC

I just feel more comfortable with a bit more safety margin as it
would add very little weight. I think Bill Dube's FEA of the beam will show
this area to have the highest stress. There is always a compromise
when designing anything between cost and weight. If this were a space
craft or helicopter part the beam would be highly complex as in this
photo of Richard Martin's cost no object helicopter Schertz beam. We
chose to keep it  simple and cheap and bend it up out of rectangular
sheet therefor the stress distribution is way less than the ideal constant.

Paul Lamar

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