Metalmiller Recovery Shackles. Limited qty

Thanks!

And yessir, I have about 20 powdercoated ones ready to ship.

 

that would be an E70xx electrode. OP, I am a structural engineer and deal with steel properties/welding/fabrication all day long. Let me know what materials you are using and i can give you strengths and factors of safety if you need.

 

I put in and email to my welder, I'll let you guys know the materials and would definately appreciate you working up a number for me!

 

OP, i pm'd you back regarding the information you sent me. If you want me to post it here let me know.

 

Please do, I'm sure people would like to see the math on this! Thanks a bunch!

 

I am almost sure the welder is going to be using an e70 electrode which is 70ksi minimum rating so it makes sense that it can be a little higher.

Weld strength is based on size of the weld and length of the weld. I am not sure what weld size you are using, but my guess from the pictures is conservatively 3/8" thick. This provides 5.57 kips/in of weld. (kips = 1000lbs). It seems that total weld length would be 1”+1”+2”+2” since its welded all around the 1” stock. This would give about 33,000lbs of tensile strength. In the weld. Some practices allow for this capacity to be multiplied by 1.5 due to the direction of load being applied perpendicular to the weld direction, however since recovery is seldom accomplished by pulling straight back, I think the 33,000lbs (33kips) would be a good number in terms of weld strength (assuming 3/8” thick weld throat.) If the thickness was 7/16” the capacity would be in the neighborhood of 39kips.

The 2” stock rated at 70ksi will have a tensile strength of 280kips so that will never rupture in tension. The 1” A36 is a little harder due to the hole, however, assuming that you have a 1” bolt hole, with a 1” bolt bearing on the a36 piece, you would have approximately 36kips of strength out of that piece.

So in general, you product should work around 30kips assuming the welds are up to par. The limiting piece would be the shackle bolt. My assumption is that the bolt is probably type A325 and 1” in diameter, giving it a shear strength (since it is loaded perpendicular to its direction) of about 30kips.

Hopefully this gives you some idea into the strengths of the materials. In other words, the welder saying that the truck will break before the shackle is correct. Also note, that these numbers are estimates and are for information purposes only, so don’t hold me to any of these values. LOL. Also let me know if any of my assumed materials are incorrect (shackle bolt in particular).

-Adam

 

Mine just came today! Looks pretty well built and I already told my old man I can give him a tow when his truck gets bogged down

 

Great!

I have plenty more ready to ship out for anyone interested

 

I am a civil engineer that deals mostly with structures, and wanted to comment that these values are accurate. I have not bothered to do out the calcs to back these up, but all the assumptions are valid. This item is definatly overdesigned. The only way I could see this failing is through a heavy impact load perpendicular to the truck breaking on side of the weld. But you would have to hit it hard and would likely damage the truck also.

 

Engineering aside, I dragged out a Dodge Dakota yesterday and a Ford F150 this mornig with this thing so throw away the calcs, I've got 'real world data'. BTW, I'm an civil engineer also, good to see another on this site

 

Thanks for the positive feedback. I knew these things would hold up, it's still nice to hear it from others!

 

What is the procedure for ordering one of these? Thanks.

 

Pm Metalmiller

 

Thanks, PM sent.

 

How many more do you have?

 

I have about 15 left. Just shoot me a pm and ill send one your way. I'm on the road today but will be responding to all pms tonight

 

Any left??

 

Hi nice recovery shackle. How about answering my PM concerning the batman emblem I paid for three weeks ago. Is it made if not whats the deal. Thanks-Teddy

 

Subbed for future purchase

 

I have 10 powdercoated and ready to ship. PM me if interested! I'll sell em on a first come first serve basis.