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Back to work today. I spent yesterday trying to put all my suspension down on paper. It takes less time to actually build it than it takes to draw it!
This pile of tubes is about to become the lower subframe of my front suspension.

Working from the drawing that I did the other day.

This is the famous tube notcher. I couldnt get any action shots because my lazy wife didnt want to come outside........its only 43 below with the windchill????

This is the notchs that it makes and they arent bad for the grand sum investment of zero dollars.

In this shot you can see the previously notched tubes are laid out for welding.

Here are a couple of shots of the notcher and how it works. You basically slide the tube up against the stop and cut the corner off of one side. Turn the tube over and cut the corner off the other side. You now have a nice fish mouth that is more than adequate for mig and acceptable for tig.



Here is the front subframe welded up, you will notice that the 2 crossmembers are not welded in at this point. The are for the rack mounting and the front strut to attach to. Because these are not fully finalized yet they are currently for show.

The lower subframe to be the most efficient had to be narrower than the nain chassis. It also had to be kicked up about 4 inches from the bottom of the car.

This is an idea that I had that would help me control the bump steer, if I built the front suspension with o caster I could just about forget about bump steer in all areas of suspension travel. Then I would just angle the entire subframe up 3 degrees. Seems simple what do you guys think?

This is where having friends comes in real handy. I dont have one of these in my one stall garage.

Let the games begin!!!!

Here are the nice tabs that we made for the suspension attachment points.......too
bad that I dont like them now. I will use them in other places but after I looked at them they arent strong enough for front suspension components. I will have to get them remade out of thicker material.

Either way works, but also consider your anti-dive/lift.

You were talking about ackermann before. Dwarf cars use ackermann. It reduces understeer. Steve Smith has a good book on dwarf's that is directly applicable to what your doing right now.

I like your tool organizer in the background. I think I'll be making something similar.

You should have a go at this brilliant little software as well...

http://www.ozhpv.org.au/shed/tubemiter.htm

I figure that a small amount of antidive is liveable, even the angle that I showed was exagerated for demonstration purposes.As for the organizer in the background that was one of my first attempts at carpentry. It actually came out well!!!!!! The only problem is that it was supposed to be a bolt and nut rack and my dad threw a bunch of his junk in there first. So instead of throwing all his stuff out I threw him out instead. Parents, you have to be strict with them.

Bump steer comes from more than one plane, it comes from 5 that need to be eliminated, accounted for or made to work for you.

Where the rack is in longitudal distance, height, of course how long the steering arms are compared to the LCA's, suspension deflection and roll of the upright during caster change (which I think is what you are refering to above?). And thats just in a straight line.

0 caster gain may help you on loose stuff where the shoulder of your tyre may bite in harder but on harder stuff it's generally not a good thing to have a positive camber gain rather than negative.

I'm sure I'm not getting the whole picture but if you start with 0 caster and have the LCA on that subframe above your lower balljoint will travel backwards as it goes up resulting in negative caster.

Sorry if I am misunderstanding.....

By the way, whats "the biggest thing in motocross" and whats with the Katoom?

The biggest thing in motocross refers to me.That is a 525ktm and I dwarf it.
At 6-4 and 325lbs. I believe that I may have a claim.
As for the lower control arm traveling backwards under bump that is entirely true but the upper will also move at the same rate and the caster will remain stable.
As for the dwarf cars using ackerman I believe they have it for the same reason the chevette had it ,because the spindles are stock parts that cant be modified.
We are under no limitations in this respect. My reading has lead me to believe that ackerman is helpful on low speed turns(autocross) and not of any great help on high speed stuff(track car).Because the car will probably only be autocrossed until its sorted the plan will be to optimize for track use.

I went shopping today and this is my purchases. The guy behind the counter said its not tuesday why are you here? Get used to seeing me I need lots of stuff.

Parts guy said to me how much did you pay for those ball joints? Well he told me his price and they were on their way back to napa.151$ credit at napa for the lowers and replaced with the new ones for 28$ , for both!!!!

The template for the lower ball joint plates. Got the cardboard at the restaurant I had breakfast at this morning. First I made a winter front for my dodge diesel and still had lots left over for pattern making.Oh yea its 40 below with the wind chill again.

Here are the lower plates roughed out.

Here they are with all the goodies attached..

Here is another view of the ball joint plates. I made them out of 3/8 material , this may be slightly heavy but they receive the most abuse. I can allways drill them to lighten them later; besides the clevis,s are 3/8 also.


The next three shots are of the upper ball join plates and they are 1/4 thick .
They will be trimmed later when the A arm points are figured out.

After I get some new suspension tabs made up the front end will go together fast. I also need to find some tubing that I can thread up for my suspension links.

Ego,
I think you are definitely setting a speed record here, and it ain't even moving yet!

Are you running shocks to the LCA? I'd be concerned about the torque going through that clevis. I ain't smart enough to know if that's acceptable or not, but I've never seen a clevis used in beam loading like that. I'd be darned sure to keep the lower shock mount as close to the ball joint as possible to reduce side load on the clevis.

-dave

The plan is to run a pushrod suspension. The attachment point will be centered at the ball joint. I thought about the same things as you and dont feel that it will be a problem. If the clevis ever bends I can replace that area with a solid tube.