Cage Build Pictures, 1936 Buick

[xxobuick]

Here are some photos of the 1936 Buick Century Coupe that we are going to run in XX0/PRO at the world finals we hope.  

Cage is 1.625" OD, 4130, .095 Wall.  Fully tig welded with ER70s2 1/16 filler rod.  

Pads are directly over both frame rails.  There is bars that go through the back and attach to the rear of the frame also.  

I have the .75" thick SFI 45.1 padding, also, just not installed as of yet.


The fire bottle was bought from www.firecharger.com


Also is the Scatter shield, that we custom built out of 1/4" thick steel.

[Joe Timney]

Building a race car is not an easy task. Getting it to pass tech is not easy either. Here are a couple of items I see that are areas of concern as an experienced chassis builder and tech inspector.

Please reconsider the location of the bar in front of your head...in an accident, your seat belts will stretch more than you would over think possible and your head will hit that bar padding and jam it down, compressing your neck. This will kill you or worse. A Hans style devise uses that forward motion to slow your head down and limit that movement but you are just too close to that bar.

Your safety net is not large enough as it allows your hands and feet to come outside of the plane of the roll cage. You really need a door net or a combination of door net and inside cage plating.
Fire bottle...remember...no hose clamps. It's hard to tell what you have on them now.
Sure hope this helps.

[Peter Jack]

It appears to me that the cage isn't welded to the frame. I doubt that you'll get that through tech.

Pete

[jimmy six]

I am confused about the "plates" also since he only wrote about them and we don't see them. If the plates are welded to the frame then the rool cage is either welded to the plates or bolted in the prescribed procedure in the rule book I would not fore see see a problem.

As for the net, many see what NHRA does for the prostock catagory and assumes that is enough. The lower par of his side cage could easily be covered with sheet/expanded metal. An triagluar extention on the front edge of the net should satisfy any inspector.  With the type of side baring he has built it's going to be tough to get out anyway...Hope you make World finals...I's a great time to be there....Good Luck....JD

[mkilger]

if you look on the back of the box that your belts came in it will show you the right way to mount your belts, the way your belts mount to the floor isnt right from what i could see, but i could be wrong.

[Bob Drury]

  I don't think the top mounting of the net is legal either.  The net has to be mounted INSIDE of the tubing at the mounting points.   Bob

[Joe Timney]

Expanded metal equals cheese grater!!! Multiple roll overs equals extra opening in fire suit at left knee!!! I have proof!!!

Door net rule is it must be inside the outside plane of the roll cage. Use a straight edge on the outside, if it touches, it can tear off with ground contact...this is straight from Kiwi Steve.

[Peter Jack]

When ever I use expanded metal I use expanded and flattened. It loses about 98 percent of its abrasive power in the flattened form. There's usually one side that's a little less sharp. I use it in areas where I'd like a little less rigid surface than a flat sheet.

Pete

[Joe Timney]

I now use .060 alum. and fasten on SFI padding from JAZ, it's 10x20x1.0 thick...keeps the knee bruising down...also pad the dash for flailing legs.

[RICK]

Custom shaped nets are cheaper than I thought. They don't have to be one piece.  You could have one ridged mounted below, to keep your legs in. And an upper, removeable, So that you can escape. But I would have one built to cover the ENTIRE door opening.
 I don't much care for the bar right in front of your helmet.  A funny car type cage is to protect you from Top impact,,,,,It should be in front of your helmet, but above it.
  I like that you have a lot of bars, in the shape of triangles,,,,But I also like a clear escape route. In case of fire [your firebottle is not big enough, it never is) You can't get away from that thing fast enough.
  And I don't like the seatbelt mount. That eye-bolt thing, My son's great dane has straightened out several of those.


     Good luck,  RICK

[xxobuick]

Eyebolts are supplied with the seatbelts.  They are meant to be used together.  Cage does not have to be welded to the frame, the cage is welded to 1/4" thick pads, and bolted directly to the frame rail in 8 points.  Thats why we take pictures before hand, to get everything fixed.  Thanks guys.  Were new to scta rules, so thats why were wanting anything out in the wind now about our setup. 

[redrock_2003]

     In reguard to the seat belt attachement points. Rather than mounting your seat belts to tabs. (Tabs can be ripped/broken off in a violent impact.) I would HIGHLY encourage you to drill holes in the rollbar tubing at each desired attachment point and weld in a bushing. 
Just my 2 cents worth.

[NathanStewart]

The point about the seat belt hardware is that it shouldn't be mounted in shear like it is now.  Eyelet bolts should be mounted in tension.  I also agree with not mounting the seat belts to tabs that aren't in the same direction of pull.  One hard impact and those tabs will bend and then your belt go loose and really bad things start to happen.

My suggestion is to do this whole exercise again but this time with a fire suit and head and neck restraint system on.  The first suit will make you grow at least a half an inch everywhere and the HANS will make sure you didn't build a car you can't get out of.

It's hard to tell in the pics but the bars near the head look fairly close to the helmet.  It's been my experience that you don't want your helmet touching the cage.  It'll make your eyes do this: 

Also, make certain that the top of the helmet is not above the top of the cage.  Might be close now but will get even closer with a fire suit on. 

Cage looks to be over built which is good but I'm personally not a fan of "bolt in" cages in anything but unibody cars that don't have frame rails to tie to.  If you can weld the cage to pads and then bolt the pads to the frame then you should be able to omit the pads and tie the cage directly to the frame.  I know there are lots of folks who want to try and have a dual purpose car that can run can SCTA and then be used on the street but IMO too many compromises are made to make this work in many cases. 

Either way, keep going.