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Flying wire brackets#144

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Aug 12, 2018
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Tyndall mb canada
I took a few Pictures of replicating the missing flying wire brackets in .100" 4130n steel plate, over a steel 3/4" 1018 anvil i made to the id 3/4", radius relieved as per drawing.
Worked out ok imo, kinda crude way to make them but no tube is avail to suffice.
I had also spoke with a mechanical engineer friend of mine about the .120" wall thickness mild steel idea ,
from a 1x2"x.120wall tube , and he had this to say..regarding the comparisons of .95"4130 vs ms .120"
-Industry std nowadays up here in canada for ms is typical of 44000psi yield, due to cold temp requirements up here.
{be careful as usa still accepts *A36 std ms and lots is floating around down south unless u specify A44...(so i was told}
-Where as 4130 is 63000psi yield
The ratio difference in psi between each is proportional to the difference between the 2 samples., simple math
63k div by44k =1.43:1
Using a simple dimension, .100" thickness for the material for ms x1.43 or the straight ratio, would mean to be safe by min youd need a ..minimum .143" or 150" wall rectangle tube to be equiv to .100" 4130. , Which is very close to the .095 as plans spec perfect mandrel tube now non existent.
I did a bit more math focusing on thickness between .095/.120ms and the full final number i get is 53k psi @.120"min "without a safety factor."not meeting equiv 63k psi spec for 4130. Hence requiring mor wall thickness.
Interesting info imo, even tho i got 6' of 120wall 1x2 tube lol
I even tried to press between dies the .100 cold, for shts n giggles , it didnt like it as u can see in one shot.
Hope it helps anyone going fwd, theyre easy to make.
Just gotta drill em and trim up to finish shape.
Thanks for the help from forum members !


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