Watts link

[Bagged1972]

Alright guys I have a question maybe somebody can help out with I've got the rear of my 72 bagged and done but now I'm gonna need some sort of centering device so I was thinking about a watts link now the thing is I don't have the funds to throw out and buy one to just bolt up so I was thinking of fabricating my own so if any of you guys has done this point me in the right direction please pictures really would be nice. Thanks

[lolife99]

KP Components and Michigan Metal Works both sell these.
You might visit their website to get some ideas for building your own.
https://www.cachassisworks.com/c-1238-watts-links.aspx

[SCOTI]

Does anyone know if there's anything manufactured for C30's? I've seen the C10/style that bolts over the differential but never seen anything for a Dana HD70.

I've been toying w/building my own but haven't heard back from my potential parts source yet.

[Bagged1972]

Originally Posted by SCOTI

Does anyone know if there's anything manufactured for C30's? I've seen the C10/style that bolts over the differential but never seen anything for a Dana HD70.

I've been toying w/building my own but haven't heard back from my potential parts source yet.

I dont know anything about the C30's I've messed around with sme ideas for my C10 I was just thinking about making a bracket to bolt up to the rear end cover and I was just gonna get the rest from speedway motors I just wanted to see if anyone has made there own bracket and then I was gonna go from there with mine.

[Rodzzilla]

Originally Posted by SCOTI

Does anyone know if there's anything manufactured for C30's? I've seen the C10/style that bolts over the differential but never seen anything for a Dana HD70.

I've been toying w/building my own but haven't heard back from my potential parts source yet.

You might be able to get a HD diff cover similar to this http://diy4x.com/cart/index.php?rout...&product_id=69
and mount the pivot directly to the cover.

[SCOTI]

Originally Posted by Rodzzilla

You might be able to get a HD diff cover similar to this http://diy4x.com/cart/index.php?rout...&product_id=69
and mount the pivot directly to the cover.

I looked @ several manufacturers of HD 4x4 stuff but there wasn't much for HD-70's. Also, I like the fixed vs floating bell crank. I did receive my follow-up e-mail @ the end of Friday letting me know he was going to call me Monday AM to discuss my project needs.

In the meantime I tested the 'more-simple' Panhard bar that I was setting up. I can make it work but need the bed mounted to 100% validate clearances @ ride height & air'd out (I don't plan to air it out, it's more of ensuring everything clears in the event of failure). I would prefer to keep things centered regardless of height but cost is going to be a deciding factor. Hopefully I can obtain the specific parts needed to build a Watts that easily works w/my set-up @ a fair price.

[Snailed]

If I were building one I would want to know what the trade offs of having the roll center follow the ground rather than the chassis are? I see most watts links have the pivot mounted on the axle so the roll center would stay the same height even when the CG of the vehicle moves up and down. Your roll couple would always be changing wouldn't it?

[SCOTI]

Originally Posted by Snailed

If I were building one I would want to know what the trade offs of having the roll center follow the ground rather than the chassis are? I see most watts links have the pivot mounted on the axle so the roll center would stay the same height even when the CG of the vehicle moves up and down. Your roll couple would always be changing wouldn't it?

I would only do a fixed mounting/bell-crank w/floating links.

The 'migrating RC' is popular w/the bagged truck crowd because of the simplicity & locating accuracy. But, typically w/that/this crowd... the centering of the rear axle is the sole purpose for a Watts.

[Snailed]

I ended up making a Watts link Friday and thought I would show an easy way to make the center link. I used two 3/4" spherical bearings and welded the housings back to back. The rest is just 11g plate and 14g plate I cut out on a bandsaw and welded up. I sized the ends for 5/8" Heims. There is also a .110" spacer between the balls so they don't get bound up when you tighten the 3/4" bolt. You could make this part for about $60.

[panhandler62]

If nothing else; you've reminded me about how goobery *my* welding is.

Nice to see a skilled job.

[LUCKIN-FOU]

You know a wishbone that Telescopes works really good to. They come from the world of drag racing. I build them alot

[Snailed]

What defines the roll center location with a sliding wishbone setup?

[PBFAB.COM]

Originally Posted by Snailed

What defines the roll center location with a sliding wishbone setup?

It's just like a leaf sprung rear: center line of rear differential.

The "BEST" way to build a Watts is to make the crank assembly attached to the chassis and NOT the rear differential. This is due to earlier response regarding the roll center migration. "Best" is a matter of opinion and desired end result. Some guys might not care that the roll center migration is optimum or not. But may be more concerned with budget and simplicity.

Building a Watt's that pivots on the rear differential is easier and less expensive/involved. That is why it is the most common. It keeps the rear differential centered, and does a good job.

[Bagged1972]

I built the bracket for my diff cover now I'm thinking about just ordering a speedway motors kit and just using the other parts I need. What you guys think?

[Snailed]

Good start but I would add two more straps to the top and bottom pairs of bolts. Is that 1/4 x 2 flat bar? That stud should be able to take a few thousand pounds from the side and not sweat it.

[Bagged1972]

Originally Posted by Snailed

Good start but I would add two more straps to the top and bottom pairs of bolts. Is that 1/4 x 2 flat bar? That stud should be able to take a few thousand pounds from the side and not sweat it.

Yes it is I don't think it's gonna go anywhere

[Snailed]

That makes sense.

Here is a Watts link I finished today. I didn't want the rear roll couple changing dramatically so the center link is attached to the body of the car.
http://youtu.be/s_vs7oVK8o4

[PBFAB.COM]

Originally Posted by Snailed

That makes sense.

Here is a Watts link I finished today. I didn't want the rear roll couple changing dramatically so the center link is attached to the body of the car.
http://youtu.be/s_vs7oVK8o4

That's how I would do it.

Looks really good!

[Snailed]

Thanks, I hope it gives some ideas for everyone else building them.

[PBFAB.COM]

A company named Lateral Dynamics used to build them like this (still might?) for the muscle cars.

You just don't see it to often due to the complexity and price.

[Rodzzilla]

Looks like their site is no longer operational.

[Snailed]

I just looked up some pictures of the Lateral Dynamics watts link. They use a really small propeller/center link radius. If you look at the path of Watts links used on vehicles I'm pretty sure a short link like that would follow a much more pronounced S shaped path than a long one. I guess on a stiffly sprung and short travel application it's not that important and I'm sure they have weighed the compromise (no pun intended).

[mongoose]

the middle length really depends on how long you can make your arms...

i was trying to figure out a decent way to mount the chassis side system.. but just doesn't seem like there's enough room with the stock frame out back.

if i really wanted a watts link i'd probably build a mumford linkage, a lot easier to package within a trucks frame.

[LUCKIN-FOU]

I make my wish bone so it is level at ride height. In the middle of the frame. Now on drag cars they can be pretty narrow because of the tires on a truck I try to make them as wide a possible. If you look at this picture you will see how I mounted it to the frame the single end mounts to the top of the rear. If I'm doing bags I take them out and raise the rear as high as I can measure it. Then lower it all the way and measure it.