FasTrack & IT rollcage crushboxes allowed?

T

tom91ita

New member
http://www.scca.com/documents/Fastrack/10/10-fastrack-july.pdf


Allow roll cage mounting plate crush box​
Thank you for your input. The current requirements are adequate as written.
Click to expand...

it was my understanding that mounting plates can be used to slightly elevate a main hoop so that there is a "box" under the roll bar. (i think i have seen various pics of this on this forum, frequently for Spec Miatas).

does this mean that they are not allowed or they are already allowed under the existing wording?
 
If I can add to the thread...

NOT ALLOWED BY CRB

Improved Touring
1. #1231 (Ian Stewart) Allow oil coolers
Not within class philosophy.
2. #1232 (Ian Stewart) Allow open radiators
Not within class philosophy.
3. #1233 (Ian Stewart) Oil pan baffles
Not within class philosophy.

Really??? I thought radiators were open with some limitations and oil pans/baffles/coolers were open as well.​
 
The way I read it, they are not saying no boxes, but they are saying adhere to the current written rule. Hard to know, not reading the request...
 
mossaidis said:
If I can add to the thread...

NOT ALLOWED BY CRB

Improved Touring
1. #1231 (Ian Stewart) Allow oil coolers
Not within class philosophy.
2. #1232 (Ian Stewart) Allow open radiators
Not within class philosophy.
3. #1233 (Ian Stewart) Oil pan baffles
Not within class philosophy.​


Really??? I thought radiators were open with some limitations and oil pans/baffles/coolers were open as well.​
Click to expand...

They are. All I can imagine is that this belongs in another class.... Though T gets radiators too correct?
 
NOT any more!

actually, i think Chris hit it on the head in that it was likely supposed to reference Touring and not "IT"

mossaidis said:
If I can add to the thread...

NOT ALLOWED BY CRB

Improved Touring
1. #1231 (Ian Stewart) Allow oil coolers
Not within class philosophy.
2. #1232 (Ian Stewart) Allow open radiators
Not within class philosophy.
3. #1233 (Ian Stewart) Oil pan baffles
Not within class philosophy.​


Really??? I thought radiators were open with some limitations and oil pans/baffles/coolers were open as well.​
Click to expand...
 
The crush boxes are mine. I wanted the rule to disallow the welding of boltin cages, right to the floor. Anyone that has done this , knows that it makes a punch through area around the weld. Any cage that sits on the floor should have some type of load spreader,IMHO. The crush box is one of the best methods/designs.
The current rule allows the crush box, but doen not reccomend them.
Mike Ogren /Protech.
Why would SCCA not recommend a verified and much safer way of mounting bolt in cages is beyond me. SCCA stays way behind the times in many ways.
 
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Well, either your request was worded poorly, or somebody read it completely wrong, because what your post states, (disallow boltin cages frome being welded without crush boxes*) and what the summation of your letter is according to Fastrack (Allow crush boxes) is COMPLETELY different.

When I was on the ITAC, we'd get letters where we THOUGHT we knew what the writer meant, but, we had to go by his actual words, even though they were sometimes 'odd' or 'weird', just like racers have to read the words of the rule, and no inject 'intent' into them. Two way street on that.

I'd be interested to see the original letter that was sent to the ITAC.

*I'm not sure how disallowing the welding-in of them makes them any safer than merely bolting them in? I mean, if they're unsafe in your eyes when welded in why aren't they unsafe when bolted in? Isn't the punch through problem potentially the same?
 
Mike, (now that I know you) I would disagree with your assertion that a box welded to the floor would disperse the load. If anything a box welded to the floor of a car would create, for lack of a better term, blades to cut through the floor. That floor, which has been heated to its melting point as well, will have been weakened by said welding. Flat plate, the bigger the better in area, and welded on more than one plane, IMHO, would be the best strategy.
Your milage may vary!
 
Welding the bolt in cage to the floor makes the perimeter of the weld a punch through point. The bolted in cage just sits on the floor. Bolting the cage over the carpet, spreads the load better but racers cant seem to leave the carpet in.
I am sure that it was worded poorly and also read poorly..The SCCA tech guy wrote it( maybe Kim?)
Chris; The crush box is a riser box that deflects, to load the rest of the cage legs.
The pad under the box/riser is 60% stitch welded, not 100%. The pad should go up the rocker and or along the sill plate.
I will send you a pic.
 
The crushbox/pedestal has a flat surface of the same thickness as a floorplate, right? I've always wondered, what's to prevent the tube from punching through the flat surface of the crushbox?
 
The biggest problem with boxes is creating rule wording to govern their design and construction to be as safe as they can potentially be while avoiding their potential for being less safe than the current, de-facto plate on floor (knife edges on the HAZ as Chris pointed out). additionally, we have to have the "old guys" at tech make a ruling on them. plates are a simpler thing to govern and harder to do or judge wrong.

the wording of your letter may or may not have done your request justice, but it's a really difficult issue with the dispersed structure of SCCA.

Agreed that many bolt-ins are very unsafe without some sort of load distribution, particularly when welded.
 
GTIspirit said:
The crushbox/pedestal has a flat surface of the same thickness as a floorplate, right? I've always wondered, what's to prevent the tube from punching through the flat surface of the crushbox?
Click to expand...

cage04.jpg


The trick is to tie the box into multiple surfaces. You get more weld area and can connect to the sills and other panels that are thicker than the floor. And in my experience, the sheet used for boxes (this is Competition Cages in Hillsborough, NC) is way thicker than floor material.

cage05.jpg


EDIT - another shot, different car, same cage builder.

K
 
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