"Z"ing a chassis.....

[Len Geisler]

I am gooing to "Z" the frame on a pick up truck to build a ratted out pick up. My question is, should "Z"ing a frame shorten the wheels base?, or should I lengthen the frame at the cuts?

Anyone know how it is done in 1:1???

For my purposes, shortening the frame abit in the rear isn't a big deal as I need to shorten the p/u bed any way.

As always, any and all input is appreciated....

[bobss396]

A traditional Z job will lengthen the wheelbase. The Z is put in on an angle to give it strength. You can do a Z at a 90 degree angle, but will have to gusset it to put the strength back.

I'm doing one now on a '29 Ford chassis. So far I have the back done, slanted back on about a 20 degree angle for a 8" scale drop. I should have chopped a tad out of the frame rails first, but I can adjust it elsewhere. I should have done something on graph paper first, but it'll work.

I'm doing a lesser Z on the front frame rails with maybe a 3" drop, but will be keeping it more towards the horizontal. This will extend the front rails and give me more engine space.

In your case, I would lay out the chassis on graph paper and use that for a guide. Locate the wheel centers where you want them to wind up and slice & dice accordingly. Always reinforce the Z with a piece of wire held in place with CA glue.

Bob

[patrol52]

Here is a kind visual aid I did for another site asking the same question.

Notice that the wheel base is maintained even though the new pieces (gray boxes) are not vertical. Basically the center section is just dropped straight down and everything is trimmed up so it looks more nice than the square ends hanging down. Depending on how radical your drop and the space available usually dictates the angle of the gray boxes (usually more vertical in radical drops and cramped space.)

Here is the basic effect:

Note that often the Z is only done on the rear of the frame and a drop axle used in front. If you are making an open wheel thing like those pictured, you may also think about putting the front axle in front of the grill and making a "suicide" style mount on the front.

You should be able to find plastic bar stock at most hobby shops that works really well for "building" frames. If you have spare frames around, you can hack pieces out of them too. I usually just use the plastic stock and some super-glue.

[Len Geisler]

Bob / Patrol52,

Thanks for the tips!!!! Seems I may have an option or two.....Now where is that razor saw.....

[bobss396]

Great tutorial Patrol! This should be a big help. I might still snip a touch out of my chassis to get the interior to lie in a better place. I'm planning on going suicidal with my front axle.

I used .080 X .125 stock for mine, I have lots of Evergreen on hand here. It matched up with the chassis nicely.

But beware that a deep Z will push the rear way up, so you may have problems with the rear radius rods hitting the chassis rails, etc. All sorts of fun stuff. I was stuck for a few minutes and dove into the parts box and came up with a Ford 9" rear, Winston Cup kit rear trailing arms and retained the buggy spring from the '29 rear. I used a piece of 1/8" angle to locate the front of the trailing arms.

Bob

[MikeMc]

Also you can "stretch or shrink" the wheelbase as needed to get the right fit/look...Great tutorial Patrol 52!

[bobss396]

This is the Z on my '30 Ford, might be hard to see but you get the idea.

Bob

[bobss396]

That was impossible to see, try this one.