Paging all chassis gurus, need split bone pointers

Ok, so I got my split bones ready to go on. I mock everything up with the main leaf and break out the digital level to check castor. I knew that it would be excessive because there was 7* built into the perimiter frame I started with when I swept the front of the frame up another 5-6*. Now my spring perch and mock-up confirm a solid 12* of castor. I would probably run as much as 10, but 12 is a bit much for street use. This also places the rear pivot point well below the frame rails, hanging out with no protection at all.
I know what I want, now I need some ideas on how to get there. I want to install the pivots just above the bottom of the frame, as shown in these pics, with 8-10* of castor. I am thinking a tapered shim on the spring pack will take care of the perch. I don't want to cut the crossmember out and redo it.
Last question, what should I expect for tie rod issues with this layout? It's looking tight.
Please bring me some pics of how you installed the seat for the tie rod inside a frame rail at the back of the bones and some tie rod installs with such tight quarters.

Thanks in advance!

 

I don't want to insult, but are you checking caster with the wheel ride height and weight of engine on the spring?

 

You can kerf bend,and weld,the bones to put the rear pivot where you want.

 

Yes on both counts. I have quite a few ch***is' under my belt, but this is my first with split bones. No offense taken.
The axle is mocked up at ride height with the ch***is at road at***ude as if wheels and tires are installed.

 

It seems your spring is in a real bind and you need some pivoting perches....last resort is to re-do the crossmember.

 

I know, but in this case, I want the castor reduced also, so placing it in the lower half of the frame rail acomplishes both. I just need a clean install.
Seeing all the parts where they belong brings home how tight the tie rod clearance will be.
I just need some ideas.

 

Right, but there is a lot of room in the cross-member so I may put a tapered shim in to see how it sits. I'll modify the spring seat before I cut the cross-member out. I don't like the pivoting perches because the spring is still misaligned with the axle path.

That's where you can see how much castor I need to take out.

 

Why not kerf bend the frame right behind the front cross member,
to get the angle of the spring mounting surface correct ?

 

I swept the rails up to emulate 32 rails somewhat. The original design of the perimmiter frame had extra castor in the cross-member with the expectation that the flat frame would go down the road at about 3* nose down, leaving about 4* of castor in the steering.
My plans made this inapplicable from the start. Now it's time to correct it. I only need 2*, but 4 would be nice. I am not concerned at all about the cross-member. i can deal with that. I need ideas for a clean way to mount the pivot in the frame at the rear of the bones and any advice I can get on tie rod clearance.
I was just looking over the roadster B*** is doing now and I think he has answered the tie rod question.

Big question mark right now is about putting that tapered seat in the frame rail for the tie-rod end at the rear of the bones.

 

We always use adjustable perches and never had issues, and atleast 8 degrees of caster. My truck settled to about 9 degrees and i can drive at 80 on the freeway with one finger on the wheel. My bosses 32 sedan had about 12 degrees, did 180 at bonneville and we drove it to cruisenights regularly without a problem. Well pie cut rad arms and weld em up as well to get more caster...

 

Once again, you people are overthinking things. if you want to be really traditional, just eyeball it all together and it will turn out fine. Good enough for guys in the 40s and 50s..good enough for me..but then again, thats aslo why im not a professional car builder

 

Maybe I need to be a little more specific. If I hang the pivot below the frame, it will be the ONLY thing below the rails with 5" ground clearance. Doing so would give me the 12* of castor that is currently in the front cross-member.
I don't need 12* and I don't want anything hanging below the rails. If I move the pivots up into the rail, I get 8-10* of castor and I can handle the front cross-member.

I want to see how others have mounted the pivots IN the rail rather than below. I also want to see some tie rod installs under the bones. What steering arms, etc.

We have an alcohol promod aproaching 200 in the 8th with less than 10*. I am perfectly comfortable with the angles I am aiming for. I just want to see how the pivot can be installed neatly with good access to the nut on the back.

 

Only ways I see to put the tie rod in the rail is gonna be to drill and weld a tapered bung into the outside of the rail. This, of course has the inherent problem of the need for access from the rear. You can bore a LARGE hole in the inside and leave it open. I'm not saying that this is the right way, but I've seen it done.
Or you could machine a set of deep tapered sleeve bungs to allow the tie-rod taper and give access to the nut and cotter pin from the back. I would imagine that the ID of that sleeve would have to be at least 2". It would also be a real pain in the *** to get the cotter pin in and out. But it would work, be sound, and be clean. I hope that description is able to be followed.
I may be able to help with the machining if interested in doing this.

 

Not too long ago there was a article in one of the mags (RC I think) of a kit to do just that. Pretty simple really, a block with a tapered hole welded inside the rail and then boxed in at a angle. Something like this as I recall:

 

Mike, I had thought about something like that, but agree about the h***el with the pin. I have some 3" tubing that I considered recessing a pocket on the inside with and was thinking about nylon lock nuts or safety wire, but I'm not convinced.

Rootie, was the tapered pocket round or pyramid shaped? Can you elaborate? I guess I could hammer form something, but that's a deep hole, like Mike mentioned.

 

20 minutes to cut it out and 20 minutes to put it back in and it will be rite

DO IT RITE FORD GODS SAKE!!!! Easy fix to me

Plus 20 years from now the guys that owns it then wont be wondering why somoene did that

Rusty

 

Rusty, are you talking cross-member or ball joint seat for the bones? (I think I can hear you busting my chops on the cross-member)

How would you put the ball joint seat in the rail? (not under it)

 

On a side note,,do you plan on pie cuting the frame to give your mono spring room to travel,,,,the single springs have gotten a bad rap about breaking,,but the 2 that I have seen damaged is because of the minimal room allow to work properly. HRP

 

I think that r&c article used nylocks too. A lot of newer cars use nylocks on the tie rods. They need a lot of pressure to hold the taper to get them off. Probably a clamp could do it. A good idea to eliminate the cotter pin problem.
I wouldn't trust just having the bungs in the outer rail without a bushing from outside to inside.
On a lighter note, my bone mounts are low. About 4 1/2" from the ground. It isn't a location that would s****e during normal driving. With the exception of really steep driveway entrances, which I simply avoid, they are never gonna s****e. If something was that high it'd hit the 4" dropped axle first. I've had low cars and trucks for years so I have no fear about them. I drove a Caddy with 2" of frame clearance for years and never dragged the frame rails, except in driveways. I did make the mounts out of 5/8 steel through, just in case.

 

Here ya go...
http://www.rodandcustommagazine.com/techarticles/0702rc_alternative_wishbone_mounting/index.html

I'm pretty sure this is what you're looking for. They use loc***e and a nylock to secure the rod end. As far as tie rod clearance, can't you just heat and bend the arms until they work?

 

Thanks Mike. I know 5" isn't too low, but I have a country driveway to contend with. It's not friendly.

HRP, it's a 7 leaf stack. I only have the main in it for mock-up. The way it's made, the cross-member gets wider from the spring perch to the rails. it is about 4" wide on the outside. There is a lot of room to cant the perch either way without cutting the cross-member loose. I don't see any issues there.

I stewed all night on this. I have an idea for dropping a pocket into the inside of the frame with the bung already installed on the outside of the pocket. It would sandwich the bung between the outer rail and the inner pocket. I also need an accessible place to weld a nut for the front cab mounts, so maybe I can do 2 in 1. I'm really just looking for a good method, other than just slapping plate inside the rail and leaving a hole open.

 

That is too easy! It makes me feel I am over-thinking it.

Steering arms? probably. I haven't dug any up yet, so I'm looking to see what works. Again, probably over-thinking it.

Thanks!

 

Ahh, I see, you're running aftermarket spindles with no arms. A set of forged dropped arms should fit the bill just fine...

 

Why aren't you pie cutting the bones up by the weld where they mount to the perch? It looks to me like the bones are straight and your lifting the ends up until they are up by the frame rail, thus changes the axle position. My bones are pie cut & bent upward & welded. Wow...thats kinda hard to write out & have it still understandable.

Anyway...the front crossmember has the 7 degrees built into it with the frame. When you bolt up the spring with the bones being straight, then the end of them bones should probly be laying on the floor. Lifting them end up to the frame is changing the axle, so you pie cut the bones to be able to get the ends of the bones up by the frame rails without changing the axle position. Carl

 

I would modify the crossmember before I dealt with a tapered shim for the spring. Even if you don't want to cut the whole thing out, just cut out flat where the spring contacts it in the middle and adjust the angle. Like you said, the crossmember flares out on both sides leaving lots of room.
Your overthinking the bone mounting. Just make or buy some tapered bungs, weld them in and do like an extreme "step boxed" job on the inside to leave acess for tools and a cotter pin. Or go the locktight and Nylock route, that will work fine too.

 

I have that same 7, plus another 5.5 from sweeping the rails upward at the firewall. I need to take a little bit out.

 

I'm starting to think you're in my head.

I think realigning the spring pad inside the cross-member is a done deal. I like the article Thunderbirdesque shared. It looks easy to do, also.

Thanks everyone!

 

Yep.....I'd pie cut the 'bones...rather than running those ugly adjustible perches.

 

Red loc***e and safety wire. And never-seize on the taper. John

 

Eight degrees of positive caster is about where the car starts steering hard.
I'd be thinking about getting it back to 5-6 degrees positive.


Why not cut the bones and make the front piece a batwing similar to the Deuce Factory batwing in the photo and set the bones proper up with a dual threaded adjuster piece?

It would look similar to what's seen on the radius rod in the photo.


Then the only problem you may have would be tie rod/bones/interference.

The single rearmost adjuster goes through a crush tube on the frame.