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-   -   Q ab NASA re: seatback brace (https://rennlist.com/forums/racing-and-drivers-education-forum/245141-q-ab-nasa-re-seatback-brace.html)

}{arlequin 12-28-2005 01:39 PM

Q ab NASA re: seatback brace
 
i'm sure some of the nasa racers will be able to clarify this. i haven't come across it in the rulebook.

does the seatback brace have to be bolted to the seat as well or just mounted up against it?

thanks.

tar6day 12-28-2005 02:36 PM

Mine is just touching the seat back.....not bolted to it. It passed NASA tech w/ no problem. I raced 5 races w/ NASA last year.

Jeff Curtis 12-28-2005 03:52 PM

Generally, bolted through for aluminum (Kirkey type seats) and dense padding in between FIA approved one-piece racing seats and types such as Recaro SRD...the two piece types aren't allowed in PCA Club Racing anymore.

DO NOT BOLT THROUGH a fiberglass/carbon FIA approved seat, it will invalidate the certification.

TD in DC 12-28-2005 04:23 PM

Dave,

Jeff's explanation is what I have been told. Since I have a Kirkey, Kurt M and I drilled the seat and bolted my brace on.

TD

}{arlequin 12-28-2005 04:33 PM

thanks guys

}{arlequin 01-03-2006 11:07 AM

followup.

for those of you who are using the brey krause brace, is there a way to mount it WITHOUT drilling the cage crossbar? it seems like a bad idea to weaken any part of the cage.... yet that's what their instructions state...

Cris Brady 01-03-2006 11:12 AM

I have the BK brace in my 911 and I drilled the cage tube. To be SCCA legal I understand that you also need to weld in tubes inside the cage tube where the holes are, but that's not required for PCA or NASA.

If you really don't want to drill your cage, BK makes a welded attachment piece instead of the drilled one. Perhaps you can just purchase that piece.

Jeff Curtis 01-03-2006 11:15 AM

Yup, you can obtain the weld-on brackets, depending on cage tube size from BK...I drilled my cage, this is the 2nd one I've done and don't really see any issues in doing so, although I understand your hesitation. :)

Tom W 01-03-2006 02:25 PM

I thought the rules said if the seat is FIA certified (like Recaro), no seat back brace is required.

RedlineMan 01-03-2006 02:46 PM

Drilling a hole in anything weakens it. This is a simple fact. How much is open to debate. You weaken a tube when you do anything that changes its shape from round, like over tightening a clamp on it. Again, how much is open to debate.

In the strictest sense, and in general, neither of these should be done. This type of intallation is expedient, but not necessarily "proper." To compensate, you would weld a tube sleeve of near the bolt size inside each hole to reinforce the area, both against bending and crushing.

I personally try to come up with "better" solutions than drilling holes. Yes, it takes more work... sometimes a lot. You could drill a tube to install one of these, and nothing may ever happen. But... what if it did?

That is the question I ask myself every day, with every project in the shop.

Jeff Curtis 01-03-2006 03:29 PM

John, I agree with you, somewhat...if you are drilling tubing with say .060" wall thickness, and then clamp on it...I say it's an issue, but if you drill a hole through a 1.75" piece of tubing with .120" wall thickness (legal rollcage dims), that is supported by a "hoop" and cross-brace/diagonal, to say that this compromises the integrity of one's rollcage is ridiculous. I've seen severel of these drilled for the BK seatback brace, installed two of them myself, if I thought for one second this would compromise my safety or anyone elses, I wouldn't think of it.

Just my opinion, I believe you work with rollcages a lot more than me though! :D

Tom, I believe you are correct in saying that PCA states if you have a FIA approved seat, you do not have to have a back brace - that is how I am to understand it anyways. Nice to see your machine has progressed from a mild track tool to a ROCKET over the past couple of years. :)

kurt M 01-03-2006 04:16 PM

FIA seat that is IN DATE does not need a brace. If out of date it need to have the brace. The only problem I have with the BK clamp on unit is what keeps it from rotating or bending and shifting when it is realy needed?


Dave. Welding in a proper bracket is 30 min worth of work. Get a weld in unit and we can add it when we do the tow hooks.

Eli K 01-03-2006 05:02 PM

Or just get an IN DATE seat :)

}{arlequin 01-03-2006 05:03 PM

again, you come up w/ an offer i cannot refuse. thanks kurt.

kurt M 01-03-2006 07:59 PM

Damn Eli, did you have to post that image of you car? Ouch!

I would have in date seats but the two (Instruct in my car from time to time) I have now are nice never been in a wreck but are out of date by a couple of years and too expensive to replace. Hence the seat back brace, padded not drilled in the the seat and using a welded in slide tube. if you make a non bolted brace for a composite seat make the padded area larger than 30 sq/in and use the correct padding. 30 sq/in is a bit too small for my taste and mine are quite a bit larger.

I am converting an older Kirkey into a full containment with halo. Gotta start validating the purchase of the TiG somehow. Look honey, I saved $500 with a $4500 Welder! Now that is Racer Math.


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