I'm going to the track when it opens (April 2nd I believe), and I will post the new slip. You ran a 12.9 or someting right?

The baby's name is Benjamin A. Bolton, sorry.

end of thread jack:)

12.8 !!!!!! @117 haha. most people with that trap are in the low 12's or 11's. I blame the driver.

roll cage is looking just like your CAD models. Very impressive work!!

hopfully run into you tonight, I did a bunch of work to the buss last night, hope it makes it that far.

cheers

Thanks. I made a design change on the door bars. I will be use FEA to decide where the optimal placement for stiffeners is.

Nice!

well?? No pics of the custom steering system?

your probally busy with class, I have been trying to get ubong to answer a few questions before the final exam, no response to his email. he better be in his office tomorrow!

just did a little alum welding with my wp20 and gas lense, you are going to love the 20. after you go 20 you cannot go back to a 17. You will see!

I love this project log, I was inspired enough to strip my FC down to this point as well. I just need to weld so I can keep up!

Quick question though, are you going to do any seam-welding on the unibody?

You know, I'm torn on this. I hear the cost-benefit ratio is pretty low. Lots of work with little payoff, especially if the roll cage has really good mounting points.

UPdated Steering Column
 

This semester's work load has been killing me, but I managed to slap this together this weekend. There's still quite a bit of work to do on this before its usable.

http://i916.photobucket.com/albums/a...4/IMG_1311.jpg

http://i916.photobucket.com/albums/a...4/IMG_1312.jpg

http://i916.photobucket.com/albums/a...4/IMG_1313.jpg

O_O ... that's neat! Looks like the ultimate setup in adjustable steering position. I never would have thought of rigging it up like that. Also, putting 2 sets of bearings on the shaft is an interesting idea. One connected to the cage and the other mounted to the firewall? That should lend to the best feel possible from the chassis! Where did you find those mondo-bearings? They look like overkill but the more I look at em the more I wanna know what they'd feel like. I was just holding the stock steering column in my hands a minute ago... and now I don't want it anymore :p (except the telescoping feature might save my life on the street when i'm not wearing a harness)

The only thing I would suggest is doing away with the set-screw setup on the upper bearing. With the amount of vibration the steering column see's (not to mention the constant torque of you trying your best to twist that bar when your driving) that will not sit tight forever. If it loosens that set screw will add vibration to the shaft in a negative way.

Besides, why do you wanna but scratches and divots in your steering column? If possible, I would just weld that bushing to the bar directly. That would eliminate some adjust-ability to where that bearing sits on the shaft though... if you are set on the set-screw idea, then perhaps you could drill a few more in there? The More solid contact that bearing has to the shaft the better right?

I'm pretty sure you've already thought about that though... you said this is just an early mock-up after all.

nice to see some progress!!

defintally the most intresting steering system i have ever seen.

cheers

shm21284, your very skilled at what you do. I like the fact that your reworking every variable to your personal liking.

For building a car from beginning to end by yourself as a side project, your coming along quite quickly.

Thanks for the comments, guys! Hopefully this summer I'll be able to move along a little quicker, but that's racing season, so probably not (I'll be helping at the track).



I am not sure about the set screw feature. One one hand, it provides the ability to collapse if i get in a severe accident and possibly not break my wrists. If I loctite the set screws, there's less of a chance of them backing out. @ $65 apeice for the bearings, I'm not going to weld them. I thought about using a locking collar against it or turnign the shaft and fitting a c-clip but I'm not sure. I will take the car to a couple open track days to dial it in, then I will see if there's any problems with the stearing system.

The bearings look overkill, but they are quite light. They have a polymer housing and are sealed (I got them for this reason so they were both lightweight and washable with a powerwasher if I decided to do so). I got them on McMaster.com, its the best place ever. They are also ABEC 1 (American Bearing Engineering Counsel) rated, which means they are essentially slop free and quite smooth.

The Set Screw Dilemma cont.
 

I'm not sure I understand this can you explain? :scratch: Is this what you were going for?
http://www.define-spec.com/forum/pic...0&pictureid=41

Also, this is the type of steering hub I used on my SP-RX3 Pro Rally Car. You attach it by welding the steel hexagonal tip over the end of the steering shaft. The aluminum hub (which is screwed to your steering wheel hub) slides over that. A simple spring-loaded rod serves as a retainer and quick-release mechanism.
http://www.define-spec.com/forum/pic...0&pictureid=42

i think i'm going to leave it set screwed right now.

This was a horrible explanation.

I want to use the set screws because, in the event of a crash, they will allow the steering column to push forward (if you take the set screws away, there's nothing pushing back because of the universal joints connecting the column to the shaft).

I'm not sure about whether or not this is good, though, because its possible that even with loctite, that the steering shaft will be able to move. I suppose the open track day s will bring out any flaws in the system. If it can move axially, then I will either machine a groove and add a snap ring, or I will machine a collar, and weld it in place (but this removes any axial adjustibility it may have had).

So wtf did you run? Its been three weeks since the track has opened.

I ran a 1:38.3

Where's the *like* button?

thread jacks are gay
 

I went a few weekends ago, I could not run worth a shit.

The good news is I technical won every race, first a late 90's V8 mustang, then a WRX STI with a FMIC, then a V8 S10 (only because he red lighted). The bad news is I was slow as hell best ET 13.6927 best MPH 106.9. The V8 S10 ran 107 mph, but ran a 12.56 ET :(. I got to work on my 60ft times.

Funny thing is I was only at 107 at about 9000 rpm, my tires are way too small. I should be able to brake 12's with 235 and full boost.

The track guys told me I had to have an exterior battery kill before I come back. So I've been looking into that.

I wasn't building boost like normal at the track so I adjusted my boost controller map which fix think for a while. I heard a squeak from my turbo today and checked my shaft play. It was more than I like so I might be down for a while, unless baby's come with a turbo.

I could run NA but that's gay. Maybe run a huge shot of nitrous.

Most likely a quick rebuild, or an upgrade and I'll be back.

You know the first time I saw your setup I thought those tie-bars were designed so the steering column could move for ease of entry. After I looked at the angles I decided they were intended to adjust steering position based on X-Y-Z geometry.

I assumed that once set, those tie-bars would actually hold the steering column rigid and not allow it to move. Based on that assumption you can understand my confusion about the set screw when you said you designed your column to collapse somehow. If those tie bars hold that bracket rigid, and the bearing is bolted to the bracket... set screw or not that column isn't going to move because I thought you said you wanted it to be one piece.

I thought about it and the next assumption I made is that you wanted the set-screw to allow the steering wheel to break loose of the steering column in a sudden-impact situation. If the tires hit something hard enough the steering wheel might turn sharply and unexpectedly. (Thats why we don't hook our thumbs around the steering wheel) That's what I thought you were talking about when you said an impact might break your wrists.

Of course, that still didn't make sense because if you mounted the steering wheel to that bearing collar and not the shaft itself... then literally that little set screw would be the only thing holding your wheel on straight! lol. Thinking of all this made my brain hurt and that's why I drew that diagram. I still can't visualize how that bracket can move but that may just be the view of the camera angle in your photo.

So in the grand scheme of things its:

farberio > NOPR > SFC.

Even though it took me a minute and a half I had turns to contend with. :nod:

Can you re-post the diagram? I never got it.

Diagram
 

^post fail. No diagram posted.

I dunno why it isn't working? I embedded the [IMG] into the post... but I also added it as an attachment to this post.

sorry :\

I just wanted to let you know I started seam-welding my FC. It's a slow process but the results look very promising. It's neat to see the different parts of the unibody extensively fused together. Many parts of the FC seem to beg for this sort of reinforcement.

Any new progress???

No, I've been really busy with racing season. I hoped to get some work done on it last weekend but the shop was closed down. At least this winter should be a goldmine of production!

some long awaited progress
 

I did the passenger side door bars today. I went with a simple x to save weight. Even though it is not as strong as nascar style door bars, it is the passenger side... plenty of room between me and the car that hits me.

http://i916.photobucket.com/albums/a...-42-11_595.jpg

Also, I started on the base plates for the rear bars. I put the rear bar going to the top of the shock tower for vertical stiffness to reinforce against the spring force. I will be fabricating stiffening plates that tie into the frame rail for added rollover protection.

http://i916.photobucket.com/albums/a...-41-13_267.jpg

Some guy at work found this in his desk. Its a pop top from 1981... had to blow the dust off. Sadly, he wouldn't sell it to me.

http://i916.photobucket.com/albums/a...-22-19_596.jpg

Also, I picked up a 4.33 rear end. It was originally a 4.10 clutch type LSD and he had it rebuilt with 4.33 gears. Although this isn't the 5.12, I needed a 7" NA differential anyway, and got a good deal on it. The car originally had an 8" KAAZ as it was a turbo car.

Do any of the racers that run alternate transmissions feel the 5.12 is necessary if you have gear ratio options in your transmission? Eventually, I would like to get a T5 dogbox.

Fantastic build thread. Am watching!

The 5.12 is a necessity if you are running a RX-7 box with stock gears or Miata gears. With a dogbox, a 4.10 is fine since you can pick your gear box ratios. This is from experience, not what I have heard.

My 5.12 is up for sale or trade since I bought a Jerico a few months back. Depending on who built the 4.30, I might be interested in that as partial trade or you could come to Dallas and build me a new cage b/c the pictures show you do great work :)

now the fun part is welding 360 all the way around the tube by the roof. I know that some guys cut the top off. do the welding then weld the roof back on.

If you do go for the lop off the top way. There are a few tips you'll want to know about that make it much easyer to reconect the roof.:nod:

I'm just going to remove the base plates and weld them inside the car, no need to cut the roof off.

Hell that's even better.. Didn't know if you had already welded them in.

I must say. your work is very very nice.

I just used a hole saw and opened up 1 port or hole above the joint to be welded. You can weld the slug in or just tape over. Great for cage inspection later.

Grreat build but I have to be honest, some stuff is really cool. The FEA and CAD stuff is great. The frame under the car for the driver seat and the aluminum mounts need to be re-thought imho. What is your idea for the partition between the fuel cell and the driver compartment? Rules mandate a partition.

Keep up the good work!

GD

You don't need to punch holes in the roof ever. He is using the boxes to gain the clearance before the final welding. I always weld the cage from front to rear in general. The trick for doing the main hoop to halo is to drill holes in the floor or frame box/rail for the hoop to drop down a few inches. Once the top welds are done you lift it back up and slide the mounting plate under the hoop. The plate covers the hole and since it will be welded all the plate it isn't a problem.

What would you suggest as an alternative to the seat mounting?

This is all opinion. If you have rooom to move the cage around to drop it down, it it not close enough to the original roof to maximize the interior space for the driver. If you did your cage to the maximum driver compartment, then your only alternative is to remove the roof or cut access holes to weld.
Remember that there is a 3' x 2' hole called a sunroof. So a couple of 3" holes at the cage joints are nothing. If your tech inspection requires you to prove the welds, then how do you do this?

My experience is from SCORE, HDRA and rally cars where they ultrasonically check the cage integrity, so inspection holes are an imperative.

Why compromise the floor and drill holes , where there is no cage to recover the integrity? That is chassis structure that should not be compromised. It is harder to do it right than easy.

Answer to the under car seat brace is to utilize the existing seat mount lateral attachments to their best advantage. I incorporated an adjustable mount for a Sparco Pro 2000 all inside the car. You just have to think outside the box. Most seat mounts used just the added cage stucture and did not pierce the floor and compromise any ground influence. You already have the fuel cell hanging too low. Does the front of the fuel cell catch any air that before went through? Rember that any increase in frontal area slows the car down. A fuel cell hanging in the lower air is drag.



GD

Absolutely opinion, I guess in 23 years of cage building I've learned that you don't need to get the cage so close to the chassis everywhere that is nearly impossible to weld all the way around a tube. It all depends on rules but many places you don't want to cage up against the body, its better to bridge the gap with some gussets and use the cage and chassis as elements of a beam. The A pillars are one such place.

And even without a .125" thick, 30-50 sq in plate welded over it, try to tear a piece of metal with a round hole punched in it.

And I can make the main hoop close enough to the roof that you can't get a piece of paper between them but in sportscar racing the top of the windshield is where the hardest hits usually occur if the car goes shiney side down.

Opinoin is true. Rules also govren most of us too.

The up side of cutting off the top makes for nice even welds, ease of getting it right to the edge and it's easyer to skin the top to get some of the weight off the highest point of the car. Or replacing it with a Carbon.

But then again...rules rules rules....lol

Sorry for the thead jacking.... build on!

There is a lateral front seat mount beam in stock form, and there are two pads on either side of hte floor for the rear seat mounts. Connecting the two rear mounts on the floor and laying a thicker .125 x 2.00" top on the front,would make a decent base for either the aluminum mounts you have or a front to back piece of aluminum angle on the sides of your seat. Anything on the inside of the car.

GD

Wow. Only 23 years? In every car, buggy or truck I build, maximum room around the driver usually mandates that the cage be fabbed right up against the roof, or door, or floor. My car is made for me and my sons and we're all 6'3" and 200lbs. So we need all the room we can gain between the cage and helmets.

Besides, I don't want to compromise the integrity of the roof by cutting it off. Worse, IMHO, than a 3" hole.

When the tech inspector asks you if the cage is welded all the way around, has he ever said ,"Show me?"

I do Tech Inspection for local off road promoters and I ask the tough questions.

GD

I've ever had a techy say "show me" although I wish they would do things like that. 99.9% of the time you can see all of the joints with a mirror or a close eyeball even though you couldn't get a welding torch in the finished area. I've cut old cages out of cars that have had a full 3/4" of a 1.75" tube not welded. The drag racers and off road guys take cage inspection a lot more serious than SCCA or NASA ever has, there are some pretty scarey "pro" built cars running around SCCA events.

Half the fun building a cage is trying figure out the right sequence to weld it in so you can get all the way around every joint. With a little planning you can have people scratching their heads on how it was done. I've gotten quite good at welding while upside down looking in a mirror:icon_tup:

Back to the OP's build! Thanks for your work in tech, SCCA could use more like you.

Like I said before “opinions differ”,
Oldschool is true and tried.
But there are new better ways to do things. Just look at any Pro car built by factory teams. (I’m not talking about armature rank SCCA and NASA). You will see cages that tie the suspension in as well as make a safe capsule for the driver. So the roof is mostly used for looks.

Off road/rally cages are built to protect the driver in a crash with the road, trees, cliffs and maybe a car.

Road race/circle track cages are protect the driver in a crash with walls, other cars and the road.

Not saying your opinion is wrong, and don’t want to jack this tread anymore.

Like I said before “opinions differ”,
Oldschool is true and tried.
But there are new better ways to do things. Just look at any Pro car built by factory teams. (I’m not talking about armature rank SCCA and NASA). You will see cages that tie the suspension in as well as make a safe capsule for the driver. So the roof is mostly used for looks.

Off road/rally cages are built to protect the driver in a crash with the road, trees, cliffs and maybe a car.

Road race/circle track cages are protect the driver in a crash with walls, other cars and the road.

Not saying your opinion is wrong, and don’t want to jack this tread anymore.

In my nine years as an official with SCCA's World Challenge I can honestly tell you that 99% of what I saw doing annuals was impressive and our inspections very thorough.

SCCA Pro is a whole different ball game. Come out to a club race and you get to argue with tech guys about a liter being more than a quart for an emergency catch can.

Acetal differential bushings
 

I spun these little guys up today. I don't have much experience on a lathe, so this took a while.

http://i916.photobucket.com/albums/a...ket_28299_.jpg

http://i916.photobucket.com/albums/a...ket_28263_.jpg

I made a mess...

http://i916.photobucket.com/albums/a...ket_28301_.jpg

And filled this trash can up.

http://i916.photobucket.com/albums/a...ket_28302_.jpg

Happy holidays and cheers!

good to see some work getting done.

I will hopfully make it down there after finals are done. The next two weeks are going to be just crazy intense.