Leaf Spring tie down plate

Jeffncs

Well-Known Member
Joined
Apr 4, 2017
Location
Wake Forest
Starting a new thread…l

im going to make some of these for my cj7 leaf springs to use as a tie down anchor point on the front axle.

B4748129-B3C5-401B-A388-ADD66F2C70CC.jpeg

Thoughts on 3/16” vs 1/4”? I’m leaning 1/4” but that seems like overkill and I have 3/16” plate in my steel corner already.

I’ll post pics as I go, if there’s interest.
 

jeepinmatt

At least half the people are dumber than the rest
Joined
Mar 24, 2005
Location
Stanley, NC
Definitely 1/4" or thicker. That's potentially several thousand pounds of force on a thin tab. You could make the flat plate part out of sheet metal and be ok, but the stresses in the bent part and the ring definitely dictate a thicker material.

If 3/16" is all you have, and you have a welder, I'd just double plate this section and roll with it.
1621438700732.png


Will be stronger than 1/4" anyway if you do that. While you're at it, make it angled on both sides. Will be easier to cut and stronger. And then carry the double plating over to include the second bolt hole:

1621438795494.png


Also, make sure the bend angle matches the actual strap angle pretty close.
 

paradisePWoffrd

Recovering Project Junkie
Joined
Nov 5, 2005
Location
Newton, NC
I would likely put the teardrop shape in the tab, vs a round hole. similar to these:
r2543-extra1.jpg


Also, as Matt mentioned, I would make the attachment tab on the plate to match the direction of pull, vs just copy that image. Both in the bent angle, direction/corner it is coming off the plate. I believe that most aftermarket companies make their spring plates out of 3/8".
 

Jeffncs

Well-Known Member
Joined
Apr 4, 2017
Location
Wake Forest
Thanks to all! I just dropped templates off at the machine shop. He’s going to use 3/8” plate. The tab will be full width of the plate, centered and bent to a 20* angle which is darn close to my strap pull angle.

Im doing my own holes and would have to think about the tear drop shape (how to drill/cut it).
 

Fabrik8

Overcomplicator
Joined
May 27, 2015
Location
Huntersville
Thanks to all! I just dropped templates off at the machine shop. He’s going to use 3/8” plate. The tab will be full width of the plate, centered and bent to a 20* angle which is darn close to my strap pull angle.

Im doing my own holes and would have to think about the tear drop shape (how to drill/cut it).

Drill two different size holes, and connect them with a straight cut on each side that is tangent to the holes.


Some thoughts:
For the picture above, figure the plate is 1/4 thick by 1/2 wide on each side of the hook hole, with 52ksi yield, so that's probably 13k lbs to reach yield (not failure). So 6k lbs with a safety factor of 2, and there's two plates on the axle.
Making the tab full width and moving the hole away from the edge would give more section area around the hook hole, and more strength. That's the reason a teardrop hole is used; keep extra metal where you need it, and add extra clearance to insert the hook where you don't. You can do the same with a round hole by... ...moving the hole.

Probably no need to use 3/8, but it will help traction in the snow.


If you're mounting them like the Mopar guy, you could cut a big hole in the middle to save weight without any penalty. The entire middle of the plate really isn't contributing much, except snow traction.

20180901_162334-jpg.926813
 
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Jeffncs

Well-Known Member
Joined
Apr 4, 2017
Location
Wake Forest
That pic is the exact idea except on the front axle. The rear will just use axle straps. I like you snow traction comment…. My Warn 8274 helps with that too!

I follow you on connecting the 2 holes. I’ve used that approach for slotted holes, not tear-drop shaped holes but same concept. I’m hoping to keep as much material intact as possible, so planning to center the hole and keep it towards the spring plate.

If I like the setup, I may have the shop throw 2 more together for the rear axle. The template/mock-up looks really simple and convenient for snap hooks.

I wish that I had that machine shop…. Large-scale commercial outfit with all the fun toys. Brakes, rollers, lathes, mills…. The kind of place that could do about anything with metal.
 

Jeffncs

Well-Known Member
Joined
Apr 4, 2017
Location
Wake Forest
As you can see, the spring plate holes aren’t perfect. They’ll work well though - can’t see them while installed… but still structurally sound.
 

strange1

Well-Known Member
Joined
Mar 31, 2005
Location
Elkin
Cool idea, and nice execution, but it looks like one more thing to hit, bend, and/or get hung up on.
 

Jeffncs

Well-Known Member
Joined
Apr 4, 2017
Location
Wake Forest
Cool idea, and nice execution, but it looks like one more thing to hit, bend, and/or get hung up on.

Thanks. It took some time to get right, but I loved the challenge!

While potentially true for many of you harder core guys…. It may not be too much of a magnet. The bent section is only maybe an inch lower than the stock spring plate and tucked right next to the tire.

With that said, my rig sticks to the easier trails with an occasional medium for the fun of it.
 

Jeffncs

Well-Known Member
Joined
Apr 4, 2017
Location
Wake Forest
I was thinking you were going to replace the Ubolt plate. Could always sandwich it on top of the ubolt plate, to gain a little clearance.

I had thought about that option too…. and I may still do it later, but would have to extend the tab by at least 2” and it would have been a lot more work to support the Jeep to take the ubolts part. I was feeling motivated, but not that motivated. Maybe that will be “Gen 2” as that would certainly make for better clearance.
 

Jeffncs

Well-Known Member
Joined
Apr 4, 2017
Location
Wake Forest
I may be able to replace the u-bolt plate completely as you said…. If I did that, the tab length may work. Have to do some checking before I get too far down the road
 
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