Landracing Forum

Bonneville Salt Flats Discussion => Build Diaries => Topic started by: Sumner on January 07, 2008, 12:29:20 AM

Title: Seat, belts and head restraint..................
Post by: Sumner on January 07, 2008, 12:29:20 AM
(http://purplesagetradingpost.com/sumner/bvillecar-2/1-5-08-s-14.jpg)

Finished the seat.............................

http://purplesagetradingpost.com/sumner/bvillecar-2/construction%20page-85.html   

(http://purplesagetradingpost.com/sumner/bvillecar-2/1-5-08-sb-6.jpg) 

.................got the belts installed..................

 http://purplesagetradingpost.com/sumner/bvillecar-2/construction%20page-86.html 

(http://purplesagetradingpost.com/sumner/bvillecar-2/1-6-08-H-Res-15.jpg)

...............and made some lateral head restraints..............

http://purplesagetradingpost.com/sumner/bvillecar-2/construction%20page-87.html     

........................................It's been a good week,

Sum
Title: Re: Seat, belts and head restraint..................
Post by: Rex Schimmer on January 07, 2008, 01:19:38 AM
Damn lucky you're skinny Sum!! Looking good! Keep at it.

Rex
Title: Re: Seat, belts and head restraint..................
Post by: bvillercr on January 07, 2008, 01:28:50 AM
Sum, you vehicle looks very nice.  Keep up the good work, and the pictures coming.
Title: Re: Seat, belts and head restraint..................
Post by: Sumner on January 07, 2008, 10:26:08 AM
Damn lucky you're skinny Sum!! Looking good! Keep at it.

Rex

Hey the car is almost 4 foot wide almost anybody can fit into that  :-).  I got your drawings, did you get my return e-mail.  I got what appeared to be an automatic return from you saying you were on vacation.  What's the deal with that???  Save the vacation days so you can retire earlier and get to work on your lakester.

I'll post your drawings on my site and here if it is ok with you.  Let me know and do you by any chance have them in jpeg format I'm not sure I can deal with the pfd you sent them in.  They are good and pretty close to where I'm trying to go with the car.

c ya,
Title: Re: Seat, belts and head restraint..................
Post by: Dean Los Angeles on January 07, 2008, 06:15:29 PM
I think the head restraint distance is ok, but the size isn't. When you look at a crash impact you don't have much padding between you and a hard surface. The contact surface is very small. And the forces are very great.

If you look at what John Force racing implemented after Eric Medlen's accident it's obvious that the surface area was greatly expanded. Look at the crush distance between this photo and yours.

(http://www.nhra.com/2007/images/news/april/force1.jpg)
Title: Re: Seat, belts and head restraint..................
Post by: 1212FBGS on January 07, 2008, 07:16:43 PM
sum I think for what were doing your restraint are good... we want to keep the distance the head moves and decelerates to a minimum... when the brain moves and crashes inside the skull, damage occurs...but you don’t want the helmet to touch the hard padding cuz your vision will blur when you run off course on to the crunchies
Title: Re: Seat, belts and head restraint..................
Post by: Sumner on January 07, 2008, 11:03:39 PM
sum I think for what were doing your restraint are good... we want to keep the distance the head moves and decelerates to a minimum... when the brain moves and crashes inside the skull, damage occurs...but you don’t want the helmet to touch the hard padding cuz your vision will blur when you run off course on to the crunchies

I'm trying to keep the distance to a minimum without touching for the reason you mentioned.

(http://purplesagetradingpost.com/sumner/temp-pictures/force-pads.jpg)

Thanks for the input Dean.  I should be closer to the sides then what Force is in this picture.  I like the ISP pads, but wanted this to be adjustable for different helmet sizes and drivers (I'm sure Kent will want to get in the car sooner or later  8-) ).  I think it will be way better than the SCTA minimums that allow 2 inches and your head could accelerate to a higher speed before impact in 2 inches vs. 1/4 to 3/8 inch before impact.  Almost every car on the salt has the padding I'm using on their cages/roll bars that they can hit.  Doesn't make that the best though and the ISP padding might be in my future.  I guess everything is a compromise.

c ya,

Sum
Title: Re: Seat, belts and head restraint..................
Post by: rustyT on January 07, 2008, 11:58:30 PM
Sum.
After looking back on these pictures,I thought it was tight in that thing when I got in there without the seat,Im thinking we may have to widen it a little,ok, alot  :-D The new additions since I was there last looks awesome,keep working,Im going to try to get back over this weekend,hopefully it will quite snowing so I can make good time. Oh ya,good news,I found out my license is back up too 8 points,only four more and she will be good as new :evil: Talk to you soon.
                                                 Phil.
Title: Re: Seat, belts and head restraint..................
Post by: interested bystander on January 08, 2008, 01:46:05 AM
Let  Landspeed racers NOT be influenced by the work on Force's cars after the tragic Medlin happening. The system that many LSR racers have used since the Mickey Thompson  (if not before)  days- keeping the driver/rider's head confined in CLOSE proximity to the cage - with appropriate padding, of course - I FIRMLY believe is more appropriate than what Force's advisors have done- they are trying to somehow make the brain survive the estimated 45 cycles(hertz) per second vibration that ocurred with the tire puncture that caused the tragedy.

A pretty unlikely ocurrence with landspeed racing.

 Also unlikely is that any kind of head containment can assure survivability in a situation like Medlin's. (He wasn't the first- only the highest profile).
Title: Re: Seat, belts and head restraint..................
Post by: Rocky R on January 08, 2008, 11:21:38 AM
Sum,

Chassis is looking great. Love all the detail and pictures... Mike added additional padding to the cockpit of the Ack Attack in 07. When I got in it for the first time, it fit so snug I couldn't move my head freely and felt too confined. He removed and reshaped the inserts till there was just enough wiggle room where I could isolate my helmet away from the padding, but still had only minimal head movement.

I'm so glad he added the additional padding. In our crash we tumbled twice with the hatched ripped off before I hit the salt. In the days to follow I still had a sore/stiff neck. I could only imagine what it would have been like had there been more room for accelerated impact.

Keep up the good work.

Rocky
Title: Re: Seat, belts and head restraint..................
Post by: Rex Schimmer on January 08, 2008, 11:37:43 PM
Sum,
Feel free to post my sketches, I am not sure if I can make them Jpg, I'll try.

Took several weeks of over Christmas/New Years so company want me to put out the "not in office" message. Did get all of the wiring except the injection ECU wiring done on my roadster. Tested it and didn't even make smoke!! I have started doing some prelim. design work on the lakester, once I get into full speed on it, probably late this year I'll probably start a build diary to show progress. If it goes like my roadster it could be a long one. Plan to do some fairly detailed drawings for a start and because I am a "pre-CAD" engineer they will be in my standard "pencil CAD"!

Rex
Title: Re: Seat, belts and head restraint..................
Post by: Sumner on January 09, 2008, 12:44:00 AM
Sum,
Feel free to post my sketches, I am not sure if I can make them Jpg, I'll try...........................................Rex

I got them converted to jpeg.  I'll try and post them Wed.

I'm looking forward to seeing what you have in mind for your lakester and seeing the roadster in person,

Sum
Title: Re: Seat, belts and head restraint..................
Post by: 1212FBGS on January 09, 2008, 04:25:24 AM
rocky
Why was your neck sore? I have seen cages where the head is pretty limited for movement but they lacked sholder and upper body restraint so when you take a multiple g impact and the body moves but the head stayed in place you can elongate the neck and sustain injuries. The sholders need to be tight... ive seen door slammers where the belts are mounted high and tight on the racers neck so when he slams into the wall the funky ass Kirkey seat moves with the body and the belts practicly cut the drivers neck off...cool stuff....Sum your doin right with a tight cage, and it will get tighter with your suite on... if it still isnt tight enough you can have someone stick a air hose up your butt and blow you up till it is.... just fart when ya want out... hey dont laugh, it works for me.!...217mph crash in the bike liner and then my 293 crash in the car and no scratches or bruses....why do ya think i put in that on board air compressor....ok i'll stop now..
kent
Title: Re: Seat, belts and head restraint..................
Post by: JackD on January 09, 2008, 06:59:02 AM
Part of the problem for the lay down crasher is the straight, point to point belts that try to hold a curved bod to the seat that was shaped so carefully.
Another strap across the chest, from arm pit to arm pit, and a suitable release in the center, will hold you, and your delicate mass (that is different from your ass) firmly in the shape of your seating protection.
All the consideration for head protection (Hans device for example and progressive foam) is good, but if the rest of your back is broken, you will not do very well. :wink:
Title: Re: Seat, belts and head restraint..................
Post by: Sumner on January 09, 2008, 10:26:39 AM
Part of the problem for the lay down crasher is the straight, point to point belts that try to hold a curved bod to the seat that was shaped so carefully.
Another strap across the chest, from arm pit to arm pit, and a suitable release in the center, will hold you, and your delicate mass (that is different from your ass) firmly in the shape of your seating protection.
All the consideration for head protection (Hans device for example and progressive foam) is good, but if the rest of your back is broken, you will not do very well. :wink:

Jack I considered the other chest strap, but at least in my case don't feel it is necessary.  The 7th belt that goes forward in the car seems to hold the whole belt assembly very tight and I'm not able now to move in any direction more than a 1/2 inch of so if that.  I won't put it out of mind though,

Sum
Title: Re: Seat, belts and head restraint..................
Post by: Rocky R on January 09, 2008, 11:20:48 AM
Kent,

Our harness keeps me in pretty tight with very little movement. I think one possibility as to why my neck was stiff/sore afterwards had to do with the canopy ripping away from the body. As soon as it did, I remember trying to "tuck in". I gripped the controls with everything I had, worried about my arms dangling outside, and also tried to tuck my head so as not to hit the top of the roll cage when it went upside down. Don't know if I would have actually hit it or not, it was more just acting on instinct.
Title: Re: Seat, belts and head restraint..................
Post by: Sumner on January 09, 2008, 11:46:43 AM
Kent,

Our harness keeps me in pretty tight with very little movement. I think one possibility as to why my neck was stiff/sore afterwards had to do with the canopy ripping away from the body. As soon as it did, I remember trying to "tuck in". I gripped the controls with everything I had, worried about my arms dangling outside, and also tried to tuck my head so as not to hit the top of the roll cage when it went upside down. Don't know if I would have actually hit it or not, it was more just acting on instinct.

I can't imagine not being sore at least somewhere after a crash like that.  Maybe Kent has some built-in padding you don't have  :evil: or engaged his on board compressed air attached to the hose that goes..............well we won't go there.

Thanks for the encouragement on the build Rocky,

Sum
Title: Re: Seat, belts and head restraint..................
Post by: Sumner on January 09, 2008, 11:58:05 AM
Sum,
Feel free to post my sketches.......................Rex

I posted them under a new topic .............................

 "The Body" as sketched by Rex" in the build section also:

http://www.landracing.com/forum/index.php/topic,3408.0.html

........................  thanks Rex, you got pretty close to where I want to go with the body,

Sum
Title: Re: Seat, belts and head restraint..................
Post by: 1212FBGS on January 09, 2008, 08:53:14 PM
hey hey now...thats ballast not padding... I add ballast one bite at a time.....
kent
Title: Re: Seat, belts and head restraint..................
Post by: SPARKY on January 09, 2008, 09:51:43 PM
I sure like what the 7th belt does...
Title: Re: Seat, belts and head restraint..................
Post by: interested bystander on January 09, 2008, 09:56:23 PM
Apparently NHRA likes the 7th belt also, after Force's debacle, as I believe they are now required at the digs from TAFC up.
Title: Re: Seat, belts and head restraint..................
Post by: Stainless1 on January 09, 2008, 11:19:26 PM
Sum, I can't tell from the pictures, where you are installing the 1 7/8 inch trailer hitchball for your backup restraint system...  :-o  :-D
Title: Re: Seat, belts and head restraint..................
Post by: Sumner on January 09, 2008, 11:44:44 PM
Sum, I can't tell from the pictures, where you are installing the 1 7/8 inch trailer hitchball for your backup restraint system...  :-o  :-D

Everything I have uses a 2 inch ball  :-P. 

And here I thought you were posting to give me the dates you would be over here to help me get the motor up and running.  Seriously I do have a couple questions if I could call you sometime.  No speed secrets just some general get it running types.  Don't forget you want me to do something with that "soft record" before you put it out of reach  :cry: .

c ya,

Sum
Title: Re: Seat, belts and head restraint..................
Post by: JackD on January 10, 2008, 12:00:04 AM
Apparently NHRA likes the 7th belt also, after Force's debacle, as I believe they are now required at the digs from TAFC up.
[/quote
The 7th belt, that is designed to tension against the shoulder straps,
 and keep the harness from rolling up and allowing your lid to compress your neck in an upset, was first used in the car that Kent went on his head with.
Subsequent to that , the SCTA rule was modified for certain seating positions.
NHRA is following SCTA again. :wink:
   
Title: Re: Seat, belts and head restraint..................
Post by: interested bystander on January 10, 2008, 12:22:09 AM
Hate to correct the post by JACKD, but NHRA is recognizing the SIXTH  and SEVENTH belts.  FIVE point is what's been required. I've seen a couple of examples  of the 7 point hat aren't too cool. Dennis Taylor in So Cal sells the best lash-up IMHOP.
Title: Re: Seat, belts and head restraint..................
Post by: JackD on January 10, 2008, 12:45:50 AM
They all must be SFI approved and tested before they can be sold, and are manufactured to the same specification.
A search around here will suggest the value if the 6 point harness,
and prior to that, it was popular to put a small bulkhead feature in the base of the seat to keep you from going forward (tunneling), but that put a great deal of pressure on the base of your spine that was not a good idea.
If you ever crashed hard against a single crotch strap, the future of you functionality would be in jeopardy.
 The 7th point originated with a Bonneville car, and the SCTA rule reflects the requirements.
Title: Re: Seat, belts and head restraint..................
Post by: 1212FBGS on January 10, 2008, 01:34:24 AM
When i first started racing the car the SCTA tech guys didnt like my harness system.. there was a big scuttle about it amongst all the tech guys when i first showed up. they actually wrote in my log book that "I had an unconventional harness and they didnt recommend it?" but figured it looked safer so they let me race it.  Then we rolled in aug the tech guys impounded my log book... i forgot who it was, but later a SCTA inspector came over and asked "did they really write in your log book that they didnt like your belt system?" I would like to thank Jack Dolan for designing it and Auto Power for building it... It did its job and saved my life... oh and I didnt even get a scratch
love ya jack and wheres my 5 bucks
kent
Title: Re: Seat, belts and head restraint..................
Post by: JackD on January 10, 2008, 05:25:03 AM
Ya, and you ain't gonna get any of my scratch either !
I would rather owe it to you than beat you out of it. :wink:
Title: Re: Seat, belts and head restraint..................
Post by: Stainless1 on January 10, 2008, 09:16:42 AM
Sum, I'll PM you my number, speed secrets  :? wish I had some, but I'll tell you everything I know  :|
Title: Re: Seat, belts and head restraint..................
Post by: Sumner on January 10, 2008, 10:24:01 AM
Sum, I'll PM you my number, speed secrets  :? wish I had some, but I'll tell you everything I know  :|

I got the number, thanks, I'll call,

Sum
Title: Re: Seat, belts and head restraint..................
Post by: SPARKY on January 10, 2008, 11:38:28 AM
Jack,  I drove a car with and without the 7th strap---There was a HUGE difference in ability to control head movement during a run after instilation--especially BUZZED eyballs. :-)
Title: Re: Seat, belts and head restraint..................
Post by: JackD on January 10, 2008, 12:44:08 PM
Another sobering thought is the BUZZED meat behind the eyeballs. :wink:
TAKE CARE
Title: Re: Seat, belts and head restraint..................
Post by: Bob Drury on January 10, 2008, 01:30:52 PM
Would that be what they call "head cheese"?   :-D