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General Forums => The Mess Hall => Topic started by: neale_rs on December 31, 2011, 09:11:43 AM

Title: Rear spring plates idea
Post by: neale_rs on December 31, 2011, 09:11:43 AM

I'm considering trying to get something like this made locally:

For under the springs: 

(http://i138.photobucket.com/albums/q277/neale_rs/2978192300044660774S600x600Q85.jpg)

and a Dynatrac style plate on top of the axle:

(http://i138.photobucket.com/albums/q277/neale_rs/images.jpg)

and then use straight bolts instead of u-bolts.

The under spring plate requires some bending that might be hard to get done (I don't think welding the bottom and side pieces would be safe enough) so I might just end up going with the Dynatrac style setup.  Any comments/opinions?

Title: Re: Rear spring plates idea
Post by: sharpxmen on December 31, 2011, 10:23:58 AM
the reason you use u-bolts is that they wrap around the tube or spring (they deform while you torque them), if you use straight bolts you lose that part of the tightening process and wont be as strong, my opinion. Why not make the plate and use u-bolts?
Title: Re: Rear spring plates idea
Post by: FourbangerYJ on December 31, 2011, 12:38:22 PM
(http://i30.photobucket.com/albums/c331/FourbangerYJ/026.jpg)

Here is what I am running for my rear U bolt flip. This was made by Four X Doctor. They don't do these any more. They just do the Dynatrac ones.
You could make the Dynatrac style for a lot less then what they sell it for! They top plate if fairly thick IIRC it's about 1/2 inch.
I have my bump stop as part of the top plate.
I have the Dynatrac for the front.
You will need to add a shock mount to the axle tube, but that is not that big of a deal. There are lots of ready made ones out there or you can build your own.
Title: Re: Rear spring plates idea
Post by: sharpxmen on December 31, 2011, 12:43:49 PM
(http://i30.photobucket.com/albums/c331/FourbangerYJ/026.jpg)

that's a lot of leafs  :yikes:
Title: Re: Rear spring plates idea
Post by: FourbangerYJ on December 31, 2011, 12:47:34 PM
that's a lot of leafs  :yikes:

Nothing but pure ride enjoyment! They are real soft. About 150#. The front eye are triple wrapped.
Title: Re: Rear spring plates idea
Post by: FourbangerYJ on December 31, 2011, 12:50:16 PM
JKS use to make a u bolt flip like what you are thinking about Neale, but it looks like they stopped. They were called the B3. You might be able to find PICS doing a search.
I did find that they make the top plate out of 1/2 inch.
https://store.jksmfg.com/merchant2/merchant.mvc?Screen=UNIVUBOLT&Store_Code=JKS01&Category_Code=Leaf_Spring

They bottom plate is pretty easy. Some 1/4 inch or even 3/16 with a couple slots ground for the u bolts and a hole for the center pin.
Title: Re: Rear spring plates idea
Post by: neale_rs on January 01, 2012, 12:33:47 PM
   
It looks like the JKS ones are still available for narrower springs (1.75").

http://www.4x4rockshop.com/scripts/prodView.asp?idproduct=10899


Overall it sounds like the Dynatrac style would be easier to make.  I could make the lower plate myself and just have the top plate made.  The top plate is  one thing I'm after so the bump stops can be extended easily.

Thanks for the comments and ideas.
Title: Re: Rear spring plates idea
Post by: aw12345 on January 01, 2012, 05:46:06 PM
I think your idea would work just fine, like it better than the U bolts and if made right should be more than strong enough. The u bolts at the bottom works, but I would be somewhat afraid you would knock them out of place when you bang them hard enough on a rock
Title: Re: Rear spring plates idea
Post by: neale_rs on January 02, 2012, 04:03:41 PM
Thanks, I'll keep thinking it over, have plenty of time to decide.
Title: Re: Rear spring plates idea
Post by: aw12345 on January 02, 2012, 04:09:38 PM
I would find a piece of rectangular tubing 1/4" wall that has the inside width that is the same as the outside width of the leafsprings, slice the top off weld 4 ears on and you are good to go
Title: Re: Rear spring plates idea
Post by: sharpxmen on January 02, 2012, 04:38:19 PM
2.5'' square tubing 0.250 wall would be 2'' inside which is what the YJ leafs are if i remember correctly, cut in 1/2 would probably work really nice for exactly this like Art said, probably 4 or 5'' long piece will do. Make sure you cut it in half on the seam (more visible inside the tube but you can also see it on the outside if there's no rust on it)
Title: Re: Rear spring plates idea
Post by: neale_rs on January 03, 2012, 08:35:30 AM
 I think the springs are 2.5" wide.  I'll look into into it and see what can be done.  Thanks
Title: Re: Rear spring plates idea
Post by: sharpxmen on January 03, 2012, 09:37:40 AM
I think the springs are 2.5" wide.  I'll look into into it and see what can be done.  Thanks
you're probably right
3'' square tubing, 1/4'' wall in that case, split in half should be fine, would give you about 1.25'' of clearance for the nuts (depending where you weld the plates and the thickness of the leaf pack). the link that was posted earlier with the 3 gussets on each side is probably best design since you'd be welding them.
Title: Re: Rear spring plates idea
Post by: neale_rs on January 03, 2012, 11:58:37 AM
It's good to know that some standard square tubing size will work.  I was thinking 4 gussets per side as close to the nuts as possible.  Maybe the forward top of the plate could be used to attach the shocks higher with no welding to the axle tubes (something else on my list of mods to do).

Title: Re: Rear spring plates idea
Post by: kashola on January 07, 2012, 06:58:52 AM
Maybe the forward top of the plate could be used to attach the shocks higher with no welding to the axle tubes

  This was my first thought as well, but wouldn't you then have to relocate the top shock mounts also?   
Title: Re: Rear spring plates idea
Post by: aw12345 on January 07, 2012, 07:03:37 AM
Lower shock mount goes up, so does the upper mount. You want to match suspension travel to shock travel or things will break. The YJ rear upper shock mounts are prone to breaking as it is
Title: Re: Rear spring plates idea
Post by: kashola on January 07, 2012, 07:18:16 PM
My point exactly.  This would be a good time to add some stability and outboard the shocks. :smile:
Title: Re: Rear spring plates idea
Post by: neale_rs on January 09, 2012, 07:39:59 AM
I'll be pretty careful about it.  I also suspect the springs are limiting the travel and not the shocks.  sharpxmen raised both lower and upper mounts and then ended up using shorter shocks with no loss of travel.  I'll be checking to see if this is the case with my YJ too.  Believe me, I'm pretty obsessive about making sure the Jeep does not damage itself!



Title: Re: Rear spring plates idea
Post by: sharpxmen on January 09, 2012, 07:50:29 AM
I'll be pretty careful about it.  I also suspect the springs are limiting the travel and not the shocks.  sharpxmen raised both lower and upper mounts and then ended up using shorter shocks with no loss of travel.  I'll be checking to see if this is the case with my YJ too.  Believe me, I'm pretty obsessive about making sure the Jeep does not damage itself!

you'd need at least shorter shocks, the problem with the stock upper mount location requires too short of a shock (not available), i moved the mount point about 3 to 4 inches forward and about 1'' upward and still had to use the shortest one available. also, too short of a shock would mean less travel by that amount (3'' shorter means 3'' less travel, but having it less vertical means less at the shock - with lift leaf springs the axle moves forward a bit when it comes down and back when goes up as the leafs are changing shape). outboarding the shocks is probably the best solution if you don't mind welding on the frame (i do so that's why i went with the relocation brackets instead).
Title: Re: Rear spring plates idea
Post by: neale_rs on January 09, 2012, 08:05:09 AM
I'll have to check it carefully.  I also want to avoid welding on the frame.  I don't think outboarding would work, not enough space between tire and frame and frenching into a YJ frame is not a good idea since it acts as a bridge between the front and rear of the springs, which is not the case with a TJ.  I might try to copy your upper shock mount design, it turned out very nice.

Thanks

Title: Re: Rear spring plates idea
Post by: sharpxmen on January 09, 2012, 08:49:48 AM
I'll have to check it carefully.  I also want to avoid welding on the frame.  I don't think outboarding would work, not enough space between tire and frame and frenching into a YJ frame is not a good idea since it acts as a bridge between the front and rear of the springs, which is not the case with a TJ.  I might try to copy your upper shock mount design, it turned out very nice.

Thanks



i beat myself for not measuring those parts before welding, if you go that route i can try and give you some rough dimensions for a head start (i'll write them down next time i'm under the Jeep). If I were to do it again i would probably move the mount point another 1/2'' to 1'' forward (as much as possible without touching the tub). the way they are right now everything is very close with the tire all the way up, not touching anything but better to have more clearance. Remember that i had to relocate my fuel filter, not a big deal but it's an extra step.
Title: Re: Rear spring plates idea
Post by: neale_rs on January 09, 2012, 08:54:26 AM
Thanks, I would appreciate having the measurements. 
Title: Re: Rear spring plates idea
Post by: kashola on January 10, 2012, 08:32:36 PM
frenching into a YJ frame is not a good idea since it acts as a bridge between the front and rear of the springs

Structurally, I see your point but haven't I seen this done quite a few times(especially with 3/4 ton Ford shock towers).  Was thinking of doing this myself, but if it's gonna cause an issue...
Title: Re: Rear spring plates idea
Post by: neale_rs on January 11, 2012, 07:36:21 AM
I think frenching could be an issue on a YJ.  With full width axles, outboarding would probably work fine with the Ford shock towers on the outside of the frame.
Title: Re: Rear spring plates idea
Post by: FourbangerYJ on January 11, 2012, 08:19:11 AM
A guy I run with has a YJ with leafs and frenched frame to make room for the outboard shocks. Seems to work fine. No issues with frame cracking or any other strength issues so far. It's been a few years and he is not easy on his Jeep!
Title: Re: Rear spring plates idea
Post by: neale_rs on January 11, 2012, 08:51:49 AM
Well, maybe it could work.  In the vertical direction it should be just as strong although it seems some twisting could come into play. I read once about a Jeep with frenched rear shocks that fell hard on the rear corner and the whole back part got bent to the side, things like that I would just rather avoid!  It could also depend on how much the shocks are frenched. I've seen some that go all the way across the frame rail and some that only go about half way across.  the best way would probably be to have the shock go through something like a tunnel in the frame rail.



Title: Re: Rear spring plates idea
Post by: sharpxmen on January 11, 2012, 08:59:50 AM
depending on the backspacing in the rims i think it can be done without cutting into the frame (which imo is the last thing you'd want) - the towers can be towards the rear so the shocks are at an angle and the tire won't get into the shock when it moves all the way up.
Title: Re: Rear spring plates idea
Post by: neale_rs on January 11, 2012, 09:22:13 AM
Toward the rear would probably have enough clearance, maybe to the front too, since the shocks are not super long coilovers.  One thing to consider is the the shock will need more travel when outboarded than when inboard of the spring.  I'm kind of leaning toward moving the lower mounts more inboard and angling the shocks out to the stock upper mount location with an adapter to account for the mounting angle.  This might be a nice, clean, and simple way to do it.