another custom roll cage
01-23-2007, 08:23 PM
#27
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Re: another custom roll cage (NAallTheWAY)
01-23-2007, 09:01 PM
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Re: another custom roll cage (gabepari)
The cage is not heat treated. I have learned that it is unnecessary. If somebody can prove to me it is, by all means I'll start doing it. lol.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by gabepari »</TD></TR><TR><TD CLASS="quote">These guys know a little bit about welding, I think
http://www.lincolnelectric.com...y.asp
Gabe
</TD></TR></TABLE>
For what its worth I agree with everything they state, and I love the er80s-d2 rod! I feel it welds better than the er70xxx rods in addition to having an end result of a slightly stronger weld.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Electron_LS-Vtec »</TD></TR><TR><TD CLASS="quote">Im not sure this would be legal for NHRA because of the rear section being tied into the shock towers with the bar across. </TD></TR></TABLE>
I'v personally built many cages in the exact same fashion and never had an issue with any.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by turboteener »</TD></TR><TR><TD CLASS="quote">Is this a drag race car or a road race car? If it is to legal for SCCA/NASA then the main hoop will need a single diagonal from corner to corner.
</TD></TR></TABLE>
Its a drag car. It's also 1.625x.083CM so no way it'll ever pass SCCA/etc. Well, at least the road race cars I'v done chassis' for called for DOM.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by turboteener »</TD></TR><TR><TD CLASS="quote">
As far as the design, not bad, you really should try and connect the rear bars to the shock towers or the chassis floor instead of loading the middle of an unsupported cross tube. Also I would like to see you move the main hoop braces out further towards the upper hoop mounting points. If you can connect as many points as possible to or close to other points your cage will be stronger.
Excellent fit up. That will make your cages very strong. You should see some of the cages that come through my shop. Very scary fit ups.
</TD></TR></TABLE>
Do you have any structural analysis concerning the connecting points or the rear bars? Why do you feel it would be better than attatching them to the "strut bar?" How do you figure its "loading the middle of an unsupported cross tube?"
I agree with you as far as connecting points together. I try to when possible but in this case (among others) the bars simply looked retarted from the back having an outward angle to them. Something I know the customers would be unhappy with. I also feel that the rear bars should attatch at the highest point of the main hoop; somewhere along the horizontal section.
I've seen some atrocities before as well! I'll look at a joint and wonder if there was supposed to be tubing there and not all that birdsh!t at the notch! In the end a happy customer with a safe cage that conforms to the rules is all that matters to me.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by gabepari »</TD></TR><TR><TD CLASS="quote">These guys know a little bit about welding, I think
http://www.lincolnelectric.com...y.asp
Gabe
</TD></TR></TABLE>
For what its worth I agree with everything they state, and I love the er80s-d2 rod! I feel it welds better than the er70xxx rods in addition to having an end result of a slightly stronger weld.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Electron_LS-Vtec »</TD></TR><TR><TD CLASS="quote">Im not sure this would be legal for NHRA because of the rear section being tied into the shock towers with the bar across. </TD></TR></TABLE>
I'v personally built many cages in the exact same fashion and never had an issue with any.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by turboteener »</TD></TR><TR><TD CLASS="quote">Is this a drag race car or a road race car? If it is to legal for SCCA/NASA then the main hoop will need a single diagonal from corner to corner.
</TD></TR></TABLE>
Its a drag car. It's also 1.625x.083CM so no way it'll ever pass SCCA/etc. Well, at least the road race cars I'v done chassis' for called for DOM.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by turboteener »</TD></TR><TR><TD CLASS="quote">
As far as the design, not bad, you really should try and connect the rear bars to the shock towers or the chassis floor instead of loading the middle of an unsupported cross tube. Also I would like to see you move the main hoop braces out further towards the upper hoop mounting points. If you can connect as many points as possible to or close to other points your cage will be stronger.
Excellent fit up. That will make your cages very strong. You should see some of the cages that come through my shop. Very scary fit ups.
</TD></TR></TABLE>
Do you have any structural analysis concerning the connecting points or the rear bars? Why do you feel it would be better than attatching them to the "strut bar?" How do you figure its "loading the middle of an unsupported cross tube?"
I agree with you as far as connecting points together. I try to when possible but in this case (among others) the bars simply looked retarted from the back having an outward angle to them. Something I know the customers would be unhappy with. I also feel that the rear bars should attatch at the highest point of the main hoop; somewhere along the horizontal section.
I've seen some atrocities before as well! I'll look at a joint and wonder if there was supposed to be tubing there and not all that birdsh!t at the notch! In the end a happy customer with a safe cage that conforms to the rules is all that matters to me.
01-23-2007, 09:52 PM
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Re: another custom roll cage (bigTom)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by bigTom »</TD></TR><TR><TD CLASS="quote">
Do you have any structural analysis concerning the connecting points or the rear bars? Why do you feel it would be better than attatching them to the "strut bar?" How do you figure its "loading the middle of an unsupported cross tube?"
</TD></TR></TABLE>
this is an issue and would not be legal for SCCA/NASA. To me it makes more sense to attach the to rear down tubes to the chassi via close to the shock mount, and weld the cross bar in between those.
Do you have any structural analysis concerning the connecting points or the rear bars? Why do you feel it would be better than attatching them to the "strut bar?" How do you figure its "loading the middle of an unsupported cross tube?"
</TD></TR></TABLE>
this is an issue and would not be legal for SCCA/NASA. To me it makes more sense to attach the to rear down tubes to the chassi via close to the shock mount, and weld the cross bar in between those.
01-23-2007, 10:50 PM
#30
Re: another custom roll cage (bigTom)
NRG!!You guys definitely got some skills building cages.. I can't beleive how close you got the hoop and front bars to the body of the car!!
01-24-2007, 07:48 AM
#31
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Re: another custom roll cage (slammed_93_hatch)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by slammed_93_hatch »</TD></TR><TR><TD CLASS="quote">
this is an issue and would not be legal for SCCA/NASA. To me it makes more sense to attach the to rear down tubes to the chassi via close to the shock mount, and weld the cross bar in between those.</TD></TR></TABLE>
We're a NASA tech inspection center for our region and I have had no issues passing someone with the rear down bars connecting to the rear strut tower brace in that way.
This is from the '07 NASA CCR.
" 15.6.11 Rear Braces
The main hoop must have two (2) braces extending to the rear. The braces shall be attached as near as possible to the top of the main hoop, and no more than six (6) inches below the top. The braces must not contain any bends*. There must be at least 30 degrees between the plane of the main hoop and the plane of the rear braces. The main hoop rear braces shall be installed to form no more than a one hundred five (105) degree angle or no less than a seventy-five (75) degree angle with the main hoop when viewed from the top. The main hoop braces may be mounted at the rear shock mounts or suspension pickup points (providing that the braces remain in compliance with all other sections of the CCR). They may go through any rear bulkhead(s) provided the bulkhead(s) is sealed around the cage braces. *There may be certain exceptions allowed for cars that cannot possible meet this “no bend” requirement. One exception is listed [Ref
15.6.11.A)]. Other exceptions may be made (not guaranteed) if all of the required bars meet the specifications for a vehicle in the next heavier weight classification and the alternative design is submitted to the NASA National Office or special allowance. "
It does not say that a rear strut tower brace is required nor does it say that the rear main hoop braces must connect to the strut towers.
So to all who say it's illegal for NASA stfu.
this is an issue and would not be legal for SCCA/NASA. To me it makes more sense to attach the to rear down tubes to the chassi via close to the shock mount, and weld the cross bar in between those.</TD></TR></TABLE>
We're a NASA tech inspection center for our region and I have had no issues passing someone with the rear down bars connecting to the rear strut tower brace in that way.
This is from the '07 NASA CCR.
" 15.6.11 Rear Braces
The main hoop must have two (2) braces extending to the rear. The braces shall be attached as near as possible to the top of the main hoop, and no more than six (6) inches below the top. The braces must not contain any bends*. There must be at least 30 degrees between the plane of the main hoop and the plane of the rear braces. The main hoop rear braces shall be installed to form no more than a one hundred five (105) degree angle or no less than a seventy-five (75) degree angle with the main hoop when viewed from the top. The main hoop braces may be mounted at the rear shock mounts or suspension pickup points (providing that the braces remain in compliance with all other sections of the CCR). They may go through any rear bulkhead(s) provided the bulkhead(s) is sealed around the cage braces. *There may be certain exceptions allowed for cars that cannot possible meet this “no bend” requirement. One exception is listed [Ref
15.6.11.A)]. Other exceptions may be made (not guaranteed) if all of the required bars meet the specifications for a vehicle in the next heavier weight classification and the alternative design is submitted to the NASA National Office or special allowance. "It does not say that a rear strut tower brace is required nor does it say that the rear main hoop braces must connect to the strut towers.
So to all who say it's illegal for NASA stfu.
01-24-2007, 08:44 AM
#32
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Re: another custom roll cage (bigTom)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by bigTom »</TD></TR><TR><TD CLASS="quote">The cage is not heat treated. I have learned that it is unnecessary. If somebody can prove to me it is, by all means I'll start doing it. lol.
</TD></TR></TABLE>
Heat treating is not necessary if you use the right rod. If you use a 4130 rod then it will need to be heat treated to anneal the weld. It will be brittle if not annealed. On thin structures it is not as necessary to heat treat.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by bigTom »</TD></TR><TR><TD CLASS="quote">
For what its worth I agree with everything they state, and I love the er80s-d2 rod! I feel it welds better than the er70xxx rods in addition to having an end result of a slightly stronger weld.
</TD></TR></TABLE>
I have not used that rod but after looking at the numbers it is a much better rod for Chromoly. You get really close to the 95KSi of the parent material with that rod.
Check out this info:
http://www.tigdepot.com/faq.html
Good info for the Cromoly stuff.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by bigTom »</TD></TR><TR><TD CLASS="quote">
Do you have any structural analysis concerning the connecting points or the rear bars? Why do you feel it would be better than attatching them to the "strut bar?" How do you figure its "loading the middle of an unsupported cross tube?"</TD></TR></TABLE>
Yes. If you look at the cross tube, in the event of an accident the tube will be loaded in bending. That is really bad. You want steel tubing loaded in tension and compression only. Having tubing dead head into an unsupported is tube is always a bad idea, but I realize it can't be avoided in a few instances. But as a rule it will always be stronger to attach the rear braces for the main hoop to the strut/shock towers or the frame rails directly. If you take a mock up joint and weld it up like you have the setup now and load it in a press, you will see what happens. Now take a straight tube and load it in a press and exert the same force in compression instead of bending. Which one bends first. You will find the tube loaded at 90 degs will fail rapidly compared to the tube loaded in compression.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by bigTom »</TD></TR><TR><TD CLASS="quote">
I agree with you as far as connecting points together. I try to when possible but in this case (among others) the bars simply looked retarted from the back having an outward angle to them. Something I know the customers would be unhappy with. I also feel that the rear bars should attatch at the highest point of the main hoop; somewhere along the horizontal section.
I've seen some atrocities before as well! I'll look at a joint and wonder if there was supposed to be tubing there and not all that birdsh!t at the notch! In the end a happy customer with a safe cage that conforms to the rules is all that matters to me.
</TD></TR></TABLE>
Gotcha, I understand the complications fitting the cage tight to the body and still getting an efficient job done.
I had a car in a while back that had a 1in triangle of weld material built up around the base of a couple of main hoop braces. Looks like the fellow, just built it up until it covered up the burn through/bad fit. I would not be unhappy to have one of your cages in my car. They are very well built. The fit up is some of the best I have seen . I would just change the way the rear bracing is structured.
</TD></TR></TABLE>
Heat treating is not necessary if you use the right rod. If you use a 4130 rod then it will need to be heat treated to anneal the weld. It will be brittle if not annealed. On thin structures it is not as necessary to heat treat.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by bigTom »</TD></TR><TR><TD CLASS="quote">
For what its worth I agree with everything they state, and I love the er80s-d2 rod! I feel it welds better than the er70xxx rods in addition to having an end result of a slightly stronger weld.
</TD></TR></TABLE>
I have not used that rod but after looking at the numbers it is a much better rod for Chromoly. You get really close to the 95KSi of the parent material with that rod.
Check out this info:
http://www.tigdepot.com/faq.html
Good info for the Cromoly stuff.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by bigTom »</TD></TR><TR><TD CLASS="quote">
Do you have any structural analysis concerning the connecting points or the rear bars? Why do you feel it would be better than attatching them to the "strut bar?" How do you figure its "loading the middle of an unsupported cross tube?"</TD></TR></TABLE>
Yes. If you look at the cross tube, in the event of an accident the tube will be loaded in bending. That is really bad. You want steel tubing loaded in tension and compression only. Having tubing dead head into an unsupported is tube is always a bad idea, but I realize it can't be avoided in a few instances. But as a rule it will always be stronger to attach the rear braces for the main hoop to the strut/shock towers or the frame rails directly. If you take a mock up joint and weld it up like you have the setup now and load it in a press, you will see what happens. Now take a straight tube and load it in a press and exert the same force in compression instead of bending. Which one bends first. You will find the tube loaded at 90 degs will fail rapidly compared to the tube loaded in compression.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by bigTom »</TD></TR><TR><TD CLASS="quote">
I agree with you as far as connecting points together. I try to when possible but in this case (among others) the bars simply looked retarted from the back having an outward angle to them. Something I know the customers would be unhappy with. I also feel that the rear bars should attatch at the highest point of the main hoop; somewhere along the horizontal section.
I've seen some atrocities before as well! I'll look at a joint and wonder if there was supposed to be tubing there and not all that birdsh!t at the notch! In the end a happy customer with a safe cage that conforms to the rules is all that matters to me.
</TD></TR></TABLE>
Gotcha, I understand the complications fitting the cage tight to the body and still getting an efficient job done.
I had a car in a while back that had a 1in triangle of weld material built up around the base of a couple of main hoop braces. Looks like the fellow, just built it up until it covered up the burn through/bad fit. I would not be unhappy to have one of your cages in my car. They are very well built. The fit up is some of the best I have seen . I would just change the way the rear bracing is structured.
01-24-2007, 03:25 PM
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Re: another custom roll cage (david@didrace.com)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by david@didrace.com »</TD></TR><TR><TD CLASS="quote">
It does not say that a rear strut tower brace is required nor does it say that the rear main hoop braces must connect to the strut towers.
So to all who say it's illegal for NASA stfu. </TD></TR></TABLE>
Ummmm have you ever heard of the little thing about "if it doesn't say you can you can't". Those are required bars, so you must fallow the letter of the rule.
For non required bars you can do what ever you want with them. Although a car had some carbon fiber non required bars and the tech inspector wasn't happy.
I can send a email to Larry, Ken for clarification.
Do you issue log books? or just do HPDE tech.
It does not say that a rear strut tower brace is required nor does it say that the rear main hoop braces must connect to the strut towers.
So to all who say it's illegal for NASA stfu.
</TD></TR></TABLE>Ummmm have you ever heard of the little thing about "if it doesn't say you can you can't". Those are required bars, so you must fallow the letter of the rule.
For non required bars you can do what ever you want with them. Although a car had some carbon fiber non required bars and the tech inspector wasn't happy.
I can send a email to Larry, Ken for clarification.
Do you issue log books? or just do HPDE tech.
01-24-2007, 03:38 PM
#34
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Re: another custom roll cage (slammed_93_hatch)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by slammed_93_hatch »</TD></TR><TR><TD CLASS="quote">
Ummmm have you ever heard of the little thing about "if it doesn't say you can you can't". Those are required bars, so you must fallow the letter of the rule.
</TD></TR></TABLE>
From NASA CCR.
" 15.6.17 Additional Reinforcement
Any number of additional reinforcing bars are permitted within the structure of the cage provided that they are installed strictly for safety and do not violate CCR Section #15.6.2 Intent. This rule does not permit reinforcements in classes with spec cages. All required bars must be made of the same material and meet with at least the minimum specifications for size and thickness. "
Modified by david@didrace.com at 6:48 PM 1/24/2007
Ummmm have you ever heard of the little thing about "if it doesn't say you can you can't". Those are required bars, so you must fallow the letter of the rule.
</TD></TR></TABLE>
From NASA CCR.
" 15.6.17 Additional Reinforcement
Any number of additional reinforcing bars are permitted within the structure of the cage provided that they are installed strictly for safety and do not violate CCR Section #15.6.2 Intent. This rule does not permit reinforcements in classes with spec cages. All required bars must be made of the same material and meet with at least the minimum specifications for size and thickness. "
Modified by david@didrace.com at 6:48 PM 1/24/2007
01-24-2007, 06:40 PM
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Re: (blueoval557)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by blueoval557 »</TD></TR><TR><TD CLASS="quote">As stated, heat treating IS NOT needed unless welding something over about .125". 4130 has been used for YEARS in racing, and never been heat treated. Youll never have a problem with tech inspection.
Kyle</TD></TR></TABLE>
If you check out Engineer to Win, a book written by a guy you might recognize, Carroll Smith, you'll find that it is recommended to post heat in all chromemoly material over 0.065 inch.
This is not some guy that is a keyboard warrior from california, he is a well known engineer in the racing world, and has writen many books... This is not just structural welding for a house or a frame that is ment to drive on the roads like dodge, it is a race car engineering book... Check your sources when it comes to engineering a race car I stick with Carroll...
Modified by Electron_LS-Vtec at 10:56 PM 1/24/2007
Kyle</TD></TR></TABLE>
If you check out Engineer to Win, a book written by a guy you might recognize, Carroll Smith, you'll find that it is recommended to post heat in all chromemoly material over 0.065 inch.
This is not some guy that is a keyboard warrior from california, he is a well known engineer in the racing world, and has writen many books... This is not just structural welding for a house or a frame that is ment to drive on the roads like dodge, it is a race car engineering book... Check your sources when it comes to engineering a race car I stick with Carroll...
Modified by Electron_LS-Vtec at 10:56 PM 1/24/2007
01-26-2007, 05:56 PM
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Re: (Electron_LS-Vtec)
sorry but chromemoly should be heat treated/stress relieved, i discused this topic with my welding and joining professer and he agreed that stress relieving would be necessary.
01-27-2007, 11:26 PM
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Re: (MI EP)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by MI EP »</TD></TR><TR><TD CLASS="quote">sorry but chromemoly should be heat treated/stress relieved, i discused this topic with my welding and joining professer and he agreed that stress relieving would be necessary.</TD></TR></TABLE>
There ya go folks! I must start heat treating because your welding and joining professor said its necessary!
There ya go folks! I must start heat treating because your welding and joining professor said its necessary!
01-28-2007, 02:47 PM
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Re: another custom roll cage (bigTom)
excellent roll cage comrade...it will handle ***** to the wall...chrome moly tubing??...and what tubing thickness??
01-28-2007, 03:28 PM
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Re: (Electron_LS-Vtec)
While I have to agree that Carroll Smith is very respected, the information
is rather general. The reason for stress relieving is because of the quench effect of the surrounding steel. His statement of .065" being the thickest to do without, is general, and has a certain safety factor built-in.
The size of the object, and the filler metal used have a great deal of impact
on the brittleness of the finished product.
Using er70-s6 will yield a more ductile weld bead,and absorb most of the properties of the base metal.
If I weld a 20 foot by 6 foot piece of 4130 to another piece the same size, with 4130 filler rod, and .065" thickness, the area would be quite brittle in comparison to 2 pieces of 2"x2" x.065" being welded together.
The nhra specs .083 for the 1.75" sections, and .058" for the smaller pieces,
so welding pieces this close to within spec is not considered dangerous in terms of weld imbrittlement.
All that said, when have you heard of a chromoly cage failing within the HAZ?
Another nice piece of work Tom.
is rather general. The reason for stress relieving is because of the quench effect of the surrounding steel. His statement of .065" being the thickest to do without, is general, and has a certain safety factor built-in.
The size of the object, and the filler metal used have a great deal of impact
on the brittleness of the finished product.
Using er70-s6 will yield a more ductile weld bead,and absorb most of the properties of the base metal.
If I weld a 20 foot by 6 foot piece of 4130 to another piece the same size, with 4130 filler rod, and .065" thickness, the area would be quite brittle in comparison to 2 pieces of 2"x2" x.065" being welded together.
The nhra specs .083 for the 1.75" sections, and .058" for the smaller pieces,
so welding pieces this close to within spec is not considered dangerous in terms of weld imbrittlement.
All that said, when have you heard of a chromoly cage failing within the HAZ?
Another nice piece of work Tom.
01-31-2007, 10:44 PM
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Re: another custom roll cage (Lubo_25)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Lubo_25 »</TD></TR><TR><TD CLASS="quote">excellent roll cage comrade...it will handle ***** to the wall...chrome moly tubing??...and what tubing thickness??</TD></TR></TABLE>
yup... all chromoly.
1.625 x .083 for all the big tubing.
1.250 x .065 for the seat belt bar
1.250 x .058 for the d-bars
.750 x .058 for the oh **** bars
yup... all chromoly.
1.625 x .083 for all the big tubing.
1.250 x .065 for the seat belt bar
1.250 x .058 for the d-bars
.750 x .058 for the oh **** bars
02-23-2007, 11:58 PM
#42
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Re: another custom roll cage (dr.NAPIER)
ok I have a cage just like that one for the crx installed . The diffeerence I see is that the two angled bars from the back hoop on mine dont meet up in the middle.They are about a foot out from the hoop and mount to the bottom of the car. And all my plates are flat. With this being the way thatit is is it nhra ready
02-24-2007, 09:52 AM
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Re: another custom roll cage (gs1gsr)
have you tried putting in a seat with those bars coming in like that?
Im not saying anything bad but my passenger seat i have it to about a 1/4in to the harness bar.... with those bars angled like that it doesnt look like it will restrict the seat...
Im not saying anything bad but my passenger seat i have it to about a 1/4in to the harness bar.... with those bars angled like that it doesnt look like it will restrict the seat...
02-25-2007, 12:48 AM
#44
Honda-Tech Member
Re: another custom roll cage (rip94delsol)
I have never tried to put the seats in there yet. But check it out I just tried right now and they dont fit that sucks. I didnt think that was the correct angle either from looking at every one else there all different. Well back to the fab shop. Thanks for the observation.
02-25-2007, 10:40 PM
#45
Honda-Tech Member
Re: another custom roll cage (gs1gsr)
Ok guys I need some info on this cage. Im needing to know if the it is now will it pass a NHRA inspectioins. I know the seats will not go in so its going back and would like to know some more about how its suppose to be. Please need info ASAP.. And for the NHRA inspector I would like it to pass with the hardes inpsector of all that way I know for sure its cool.
02-27-2007, 05:09 AM
#46
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Re: another custom roll cage (gs1gsr)
You need to bring it to someone who has experience with nhra cert cages and chassis'. I would have to say whoever did those bars dosent have much experience.
02-27-2007, 12:30 PM
#47
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Re: another custom roll cage (miller)
also on plates welded to the floor im not too sure if those are allowed! my observation on the rulebook says that floor plates have to be bolted in not welded...
If you see in my first post on here you can barely see the floor plates with four bolts going through the floor and using aeromotive nuts on the bottom...
honestly if I were you I would get the bars that restrict your seat fixed then take it to your nearest inspector and have him look it over.... If it fails you fabricator should fix the problems for free....
Im not sure If you've seen how cages are inspected but the main thing is the thickness of the metal. What they use is a ultrasound device that measure the thickness of the metal... different metals require different thickness.
If you see in my first post on here you can barely see the floor plates with four bolts going through the floor and using aeromotive nuts on the bottom...
honestly if I were you I would get the bars that restrict your seat fixed then take it to your nearest inspector and have him look it over.... If it fails you fabricator should fix the problems for free....
Im not sure If you've seen how cages are inspected but the main thing is the thickness of the metal. What they use is a ultrasound device that measure the thickness of the metal... different metals require different thickness.
02-28-2007, 01:33 AM
#48
Honda-Tech Member
Re: another custom roll cage (rip94delsol)
Well I finally got a hold of the guy I( was wanting to talk to. Ken Gentry is one of the best NHRA certs around and from showing him my cage for the most part it is all correct ans certable. But its missing one pease that I notice no one on here is using. 
Right were the baclk of the floor comes up there need to be a bar. Connected to each side of the ROCKER BOXES. With 1''1/4 plates that go on the rocker box and just a bit of it on the floor bottom. THe bar across has to be min of 1''5/8 and welded to each plate. The two angle bars on the back hoop need to connect to this bar. No depending on were you mount your rear hoop plates the bar across would be in back or in front of the hoop. The plates can be mounter on the floor or up on the hump like mine And as for the plates you have two options one is welding or bolts both are correct. I will add a pic once its certed. Thanks
Right were the baclk of the floor comes up there need to be a bar. Connected to each side of the ROCKER BOXES. With 1''1/4 plates that go on the rocker box and just a bit of it on the floor bottom. THe bar across has to be min of 1''5/8 and welded to each plate. The two angle bars on the back hoop need to connect to this bar. No depending on were you mount your rear hoop plates the bar across would be in back or in front of the hoop. The plates can be mounter on the floor or up on the hump like mine And as for the plates you have two options one is welding or bolts both are correct. I will add a pic once its certed. Thanks
02-28-2007, 12:31 PM
#50
Honda-Tech Member
Re: another custom roll cage (rip94delsol)
yea thats the bar but from what the NHRA tech was telling me its not suppose to be attached to the rear hoop. Its got to be attached to the rocker boxes on each side of the car. Then tha angle bars weld to it. IT can be touching the hoop but not welded to the hoop.