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UTV's Off Road ( RZR, YXZ, Mini Buggy, Carts,etc.) => UTV Chassis and Suspension => Topic started by: nvheattreating on December 30, 2009, 02:42:19 PM
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Gents,
I thought you might find this article interesting. Bill Miller is a customer of mine and has some definite opinions on frame design and fabrication. Especially when people he knows have been killed because of improper design and fabrication.
http://www.bmeltd.com/Dragster/tubulartales.htm (http://www.bmeltd.com/Dragster/tubulartales.htm)
patm@nevadaheattreating.com
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COOL,we'll /I'll read it now. Gotta get to the shop now to do some VOODOO HT experimenting. rofl rofl
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VooDoo Heat Treating is my life. ;D
I wish my employees were as interested in heat treating as you are.
Pat
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Yeah but YOURS is MODERN VDHT! LOL!!!!
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Over and out for now .The shop is seriously calling. Got some powder coating to do in the other oven. Oops,I need a new topic. ;D ;D
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Very interesting, thanks! Looking at the chassis pictures there, typical of Funny Cars, I'm impressed with how bad the overall chassis design is. Heat treating or not is one issue, but all the heat treat in the world can't help a basically bad design. Looking at the bending moments in the pictured chassis, either before or after extra bracing, it's a recipe for disaster and an accident waiting to happen!
I wrote up a critique but it takes many words to describe and I don't want to blow bandwidth here. The forces fed into that chassis are all focused on 2 unsupported frame members so even after one run, assuming the driver lives through that, the chassis is rendered junk from then on! Scary, man, scary!
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Lets hear it J...
We have all the room you need ;D
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Please post up your opinions. We have all the room needed. As for the funny cars ,they are speciality vehicles that have proven time and time again how safe they are in an accident. We may be comparing apples to oranges . Let's talk!
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Looking at the bending moments in the pictured chassis, either before or after extra bracing, it's a recipe for disaster and an accident waiting to happen!
Dragsters are an animal unto themselves. They need to flex and bend. A really rigid chassis would do nothing but smoke the tires.
That being said, only a fool would weld heat treated tube without any post process heat treat of the entire chassis.
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Apparently that is what is done in TF and FC. I've been away from the sport for about 5 years now. I also paid little attention to TF/FC materials specs. I am just amazed at the stupidity of using WELDED JOINTS on HARDENED TUBE. That brings up the point od our ongoing arguments of 4139 vs Mild. I am a proponent of 4130 but NEVER in a million years would I use hardened OR CONDITION N. Neither have the ductility needed when welded IMO. I only use ANNEALLED 4130. I once bought some 1 5/8" .095 4130N and when bending it broke. In my pea brain I thought -none of that crap for me! Always made sure then that all I bought was annealed. I guess my blind luck pointed me in the better direction.
THat was a very informative article and much appreciated IMO. Great food for thought.
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Okay, here goes. Hard to explain without posting drawings, and I'm no doctorate in frameology, but...
On that chassis with before & after pics, looking at the sides as one big panel made up of three slant parallelograms plus a forward girder, there is first a rear triangulated wheelie bar attached at bottom to the most rearward vertical tube [v1], at a point a few inches above chassis bottom-most point, and again by a short strut brace a few inches above that connection welded to v1. It is then attached at top to the uppermost frame side rail.
From wheelie support there are 3 slant parallelograms forming driver seating area, followed by front chassis section as a girder. Next forward from wheelie support is the first tube side panel with X bracing from v1 to v2 inside a slant parallelogram, which v2 is also attached to the same upper frame tube that wheelie bar attaches to. Next forward second side panel is another slant parallelogram, but with a single bracing strut from bottom of v2 on to the top of v3, no X bracing. Next side panel again has single bracing strut from bottom of v3 to top of v4.
Directly above at v3 is the new lateral bracing hoop, with a horizontal tube as triangulation from top of new hoop to upper frame tube, connecting in front of upper roll cage forward hoop mounting point, and braced from top of v3 to top of v4. Next forward the whole front of chassis is a single cross braced girder section attached to the forward most v4 of last side panel. The entire roll cage upper is attached to the upper frame tube and nothing else, no cross bracing or gussets at attachments.
During wheelie the wheels are lifting entire chassis, pivoting on rear wheels, and wheelie support causes a downward force to be transmitted into upper frame tube, at a bending point directly in front of forward roll cage hoop. All the wheelie force will cause a pull on bottom of v1 vertical tube and further transmit a downward push into upper frame tube and stress lower tube.
As car slams down from wheelie event another force on girder front section when front wheels hit pavement is transmitted back into exactly the same hinge point in upper frame tube, just in front of forward roll cage hoop, and into the unsupported v4 connection. There's no triangulation from v4 to front girder section, so a bending hinge force impacts all girder connections at v4.
Upper frame tube is flexed downward by wheelie, plus rear wheels are leveraging frame lower tube and first parallelogram side panel upward, until wheelie is completed and then harmonics continue in upper tube, as the bouncing front end then transmits upward/downward bouncing forces trying to tear front girder off. At the same time all the force of rear wheels fighting for traction causes harmonics to set up along side panels and further impacts upper frame tube at forward roll cage hoop.
Along with thse forces there's frame twist and continuous vibration throughout structure. Added up the frame might want to fold at top tube just in front of rollbar front hoop, and girder that forms front end past driver's feet has forces on it to shear it off. Just like bending a piece of wire back & forth until it breaks the same forces are present in that chassis design, bending up & down plus lateral forces.
Hope all that came out right to explain....?
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Don't know if image attachment worked but crude added lines & arrows may help explain. Hope it posts.
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One thing that I am noticing that is lacking on the simulations is the motor. The blocks on those are solid mounted to the frame in the high stress zone and will actually contribute the the strength of the chassis. On the other hand the additional load placed fore and aft of the motor due to it's reduced flex may pose additional problems.........
Unless you have all the components on the frame in the simulation, it's nothing more than a pretty picture.......
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From what I read the issue is not construction. They want those "weak spots" in there on purpose in the event of a crash so the drivers pod will come free of the engine and fuel and hopefully slide safely to a stop .. What they need is the elongation that is absent with heat treated 4130 that allows the entire chassis to be the spring. Yes a chassis design is a POS for us but in the interest of safety they do not want the car to stay intact in the event of a crash.
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I couldn't get through the whole wall of text, but it seems he was hinting that in the Medlen crash the chassis may have failed taking out the tire.
With the amount of stress that tire shake puts into the chassis, I would be concerned about using steel that snaps instead of bending.
Overall there are far to many variables for a "beef it up" solution to work IMO. At the speeds these guys are going no chassis engineering will save them from all possible senarios.
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Yep,a chain made of rubber willl be better than a chain of glass.
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"What they need is the elongation that is absent with heat treated 4130 that allows the entire chassis to be the spring."
Yep! And ditto the chain made of rubber! What I see there is a compounding of potential failures in basic design structural intergrity, and materials and fabrication method. No other big league racing body would ever allow such a design/construction on the track.
I remember Colin Chapman and his quest for lighter & faster and I think it was somewhere around #19 - #22 disaster struck, but it's been so long ago. It cost a very precious life and Colin never fully recovered from the loss. Then later losing Clark [at Spa Francorchamps?] was over the top, too much. I never considered either crash to be Colin's fault or the fault of his excellent design, but it caused a fundamental change in design thinking and execution and soon monocoque designs appeared.
I remember one wreck of Jimmy's, I believe at Nurburgring in a #23 or 23B, and seeing him sitting in the tubular space frame Formula car afterwards grinning his funny little grin. The wheel, tires & stub axles were gone, along with all body panels, and most of the drivetrain and Jimmie was sitting there on the apron in the naked spaceframe, very alive, that time. Good design. Chapman, Costin & Phipps are good tutors even for today's space frame design.
Sorrry for rambling but it all brought back some old memories that still apply to today.
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I KNOW what you mean about surviving with a shit eating grin. ;D ;D No better feeling than realizing you're still alive. The dragster in the last pic is the one I ran for many years made of ANNEALED 4130 mostly.059 wall. the sucker ran 7.0's 1/4 for over 8 years,hundreds of runs. Ran on one of the roughest tracks in the US. MOKAN near Joplin ,Mo. I literally would bounce off the track a few inches up to about 18" in the shut down area 4-5 times every run. I have pics somewhere of it with all fours off the ground about 12". I'll try to find them. Very dangerous but WTF. It was lots of fun. The point is not that I'm comparing my 180 MPH dragster to a TF/FC but rather that 4130 can and DOES hold up well if properly built. Not bragging but ,yes,I did build it.
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Oh,the doorslammer was all 4130 also and was resurrected to live again in less than 60 days. NOT A VERY GOOD PIC. thumb down I still finished 8th in points that year at Mid America dragstrip at Arkansas City,Ks. Another VERY rough track as engineer can testify to.I built it also----- TWICE!!!! rofl
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Ouch, one of those 'done there, been that' things! Just could be that somebody up there likes you :)
The difference can be real simple on survival & longevity: ENGINEERING more than materials. Some designs you look at, supposedly topnotch stuff and you just say, "Hey, wait a minute, why did they do THAT!??"
You most likely added simple logic in your designs based on experience as to what works, what don't work. Some of the pros need to do the same....
Overall it's a downright miracle some of us survived.
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Ouch, one of those 'done there, been that' things! Just could be that somebody up there likes you :)
The difference can be real simple on survival & longevity: ENGINEERING more than materials. Some designs you look at, supposedly topnotch stuff and you just say, "Hey, wait a minute, why did they do THAT!??"
You most likely added simple logic in your designs based on experience as to what works, what don't work. Some of the pros need to do the same....
Overall it's a downright miracle some of us survived.
Most likely. I cannot take credit for it. :)
For myself I'd say that good designs require first the choice of material and then proper engineering to make it work utilyzing the chosen material. In that order.
IMO,that is where all engineering came from originally. Math and stuff was added to the mix later in the evolution of designing and real engineering to prove out new designs.
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Long as this is a safety / design thread, I ran across this car and thought - hmm something does not look right. I guess it is the bend at the upper bar that throws me. Any input on this design?
(https://dtsfab.com/proxy.php?request=http%3A%2F%2Fwww.dunebuggy.com%2Fassets%2Fclassifiedpix%2Fhuge%2F28071%2F2.jpg&hash=303f75fdb2ca964db33609a59665b24ac9fcd071)
I have no doubt a properly designed arch would take the force of a roll, but for some reason, this orange car just looks wrong.
here is another radius roof car that would survive a roll better imo.
(https://dtsfab.com/proxy.php?request=http%3A%2F%2Fwww.dunebuggy.com%2Fassets%2Fclassifiedpix%2Fhuge%2F28075%2F1.jpg&hash=e435abf4cf9a8cf3169d98cbf3808531bd35f08a)
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Personal opinion is that either one will function equally well. Aesthetically, I do not like the bottom one at all. Structurally though, I see little difference in the 2 cars in general. Yes, there are a ton of differences in where they could fail but for sand cars they seem to me they are both safe.
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The arch roof versus the bent with flat sections is about the same strength. The Kreger 10 cars have the round roofs on them and have been throughly roll tested with excellent results.
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I haven't read the frame article in a while, but I think part of the the message was that new rules forced the teams to use frames/materials in that condition.
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I believe you are correct. What really amazes me is that a long time,well respected ,chassis builder would even consider using hardened 4130 in a welded structure in the first place. I underatand why the condition N is spec'd for it's increased tensile but even it is much more susceptible to HAZ issues than annealed 4130. This opinion makes me question the failures shown of 4130 cages. Are the failures due to the 4130 or the HT condition before welding.
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One question for the pro. What really defines "heat treat"? To me it seems that most people assume HT means improved or altered in some way as to make the part harder or tougher than as manufactured to enable part to handle stresses or wear better. But what does that mean? Harder is more brittle. Tempering toughens it. Annealing softens it. But that's still not an explanation of the term heat treating that a person can use to designate anything. . IMO,NHRA failed in it's obligation to specify the exact terms of heat treat in its' standards.Yes they said conditionN -OR EQUIVALENT. They left a big door wide open on that. Hell,IMO, annealed condition is heat treated. It took treating it with heat to accomplish. Same goes for hardened-takes heat to do it. Well ,so is normalized. Soooo, WTH did NHRA mean by stating "or equivalent". McKinney took it to mean whatever he wanted it to mean,and I would have also in his shoes but I would not have used "hardened". Why do I quote "hardened"? To me condition N is heat treated or hardened also.
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Of the 2 chassis that I know of that were actually stuck in an oven, they were both normalized and stress relieved.
Heat treating without tempering would be a bad idea in My book. The whole process could turn into a large can of worms on a weldment that large...........
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I cannot speak from any point of fact but It appears in the article that McKinney was using hardened in the lower frame rails only and normalized in the rest so no post heat treating could have been done while keeping part of the chassis normalized and other areas hardened. Am I wrong? Another question is how in the world could you keep a chassis straight in an oven for anything other than tempering where the heat is much lower? There's no way you're going to keep it straight at the higher temps of normalizing the thing overall.
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As to the post on NHRA & heat treat, the answer starts with a P, ends with an S and rhymes with POS: POLITICS! The standard good old boy system run right into the ground. If you look at the politics in the original linked article the buy-offs glare out at you from the page. Big name, one of the boys, 'in' the 'In Crowd', must be allright was how the sanctioning bodies ruled the roost. Their clever exclusions of guys that knew what the hell they were doing, and inclusion of guys that simply happened to be currently building, as the only qualification for membership on the review panel, says it all.
I'd call that first car Orange Crush but I'd add 'and stab'. Both cars lack critical support members, whether they can manage to survive a rollover or not, but the second car is better thought out.
What an indescribable horror if the first car hits REALLY HARD the wrong way. Instant apendectomy & colostomy as those control arms come ramming into your guts? One should never design such that a component can ever reach the driver in a crash. Scary with that ultra-long shock on the rear too, in that respect. Could end up with your head resembling a shish-kabob? Should have a loop of tube around them as a guide for where they'd go if top shock mount broke loose at impact or a hard landing, also to prevent pole vaulting.
Also needs diagonal supports at lower points of roll cage, from about steering wheel height down to top rail at a minimum in front, slightly higher and connecting farther forward on top side rail at rear hoop. Without those a weird end-o could collapse the cage at a top-rear impact.
The sides appear to be ladder frame sections by the screws in the side panels? I'd say triangulation is much preferred, using diagonals? Would also be nice to have a horizontal tube about shoulder height behind driver/passenger for some 5-point belts and to help prevent seat fold-over? I would have also run a horizontal bar across the forward shock support hoops to stabilize. All that would only add what, maybe 10 pounds?
Second car could use the front & rear diagonals too, and both cars need a u-joint in the stab-me-hurt-me steering shafts. Second car gets huge extra points because no frame or chassis member could intrude into driver seating area to impale or injure driver. It could use a horizontal cross-chassis tube right about at rear mounting of front diagonal roll cage support tube, where verticals tie in, to cut down on frame flex.
I've been designing a chassis for about 18 months and always try to envision it as built from 2" cedar, so that support is given where needed. Then when it's built from 1.25" & 1.50" thinwall steel I KNOW it will take serious abuse. The trick is to keep it light at the same time....
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Both cars are for recreational sand use. Both would be very unlikely to be unduly unsafe for that purpose. Do I feel safe riding in lightly built sand cars ,such as those shown, in general ? No. For the same reasons you pointed out but I also know that the cages as was the question about those cars,I think, are going to serve the purpose in a rollover. I wouldn't WANT to ride in either one tho.
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I'd call that first car Orange Crush but I'd add 'and stab'. Both cars lack critical support members, whether they can manage to survive a rollover or not, but the second car is better thought out.
What an indescribable horror if the first car hits REALLY HARD the wrong way. Instant apendectomy & colostomy as those control arms come ramming into your guts? One should never design such that a component can ever reach the driver in a crash. Scary with that ultra-long shock on the rear too, in that respect. Could end up with your head resembling a shish-kabob? Should have a loop of tube around them as a guide for where they'd go if top shock mount broke loose at impact or a hard landing, also to prevent pole vaulting.
Also needs diagonal supports at lower points of roll cage, from about steering wheel height down to top rail at a minimum in front, slightly higher and connecting farther forward on top side rail at rear hoop. Without those a weird end-o could collapse the cage at a top-rear impact.
The sides appear to be ladder frame sections by the screws in the side panels? I'd say triangulation is much preferred, using diagonals? Would also be nice to have a horizontal tube about shoulder height behind driver/passenger for some 5-point belts and to help prevent seat fold-over? I would have also run a horizontal bar across the forward shock support hoops to stabilize. All that would only add what, maybe 10 pounds?
Second car could use the front & rear diagonals too, and both cars need a u-joint in the stab-me-hurt-me steering shafts. Second car gets huge extra points because no frame or chassis member could intrude into driver seating area to impale or injure driver. It could use a horizontal cross-chassis tube right about at rear mounting of front diagonal roll cage support tube, where verticals tie in, to cut down on frame flex.
I think your imagination is getting the better of you and you haven't seen many crashed cars.
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I think my 45 years of hands-on experience including tubular spaceframe & monocoque chassis design keeps my imagination on the reality side. I learned the basics from Maserati and Alfa Romeo [I think Typo 159's] and then Mercedes 300SL cars, and Colin Chapman when I worked with Lotus and Lotus/Ford, and as a pit crew chief with Lotus, in addition to my work with Volvo and their Rallye efforts, and Datsun with some of their racing before they were renamed, plus some years playing with various personal designs. Unfortunately many home builders have no idea of basics and sound fundamental engineering principles and tend to go with cool and flashy instead of intelligent. To each his own.
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Whoa,whoa,whoa. Slow down there Trigger. LOL! You've stated a lot of impressive stuff there but in no way have you let us know in what capacity you were involved or with which crews. Claims of that kind should be supported by letting us know the story behind the man. I can't argue with what you say about cool and flashy but on the other hand we must consider the application when designing ,not too much and not too little, for the actual application. I'm SURE that the names dropped do just that.
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Also mostly street oriented.
For example, your comment
What an indescribable horror if the first car hits REALLY HARD the wrong way. Instant apendectomy & colostomy as those control arms come ramming into your guts?
I've seen plenty of that type of front end crashed. The arms fold. Nothing ever came into the cab........ Except a lot of dirt........
Scary with that ultra-long shock on the rear too, in that respect. Could end up with your head resembling a shish-kabob?
I have seen shocks bent, ripped in two, mounts broken. Have never seen one get anywhere near someones head. Not saying it's imposable, just highly unlikely.
While I agree that those chassis could use some diagonals in the rear hoop and roof area, they are far from death traps. The Funco's are actually some of the better built cars out there.
Basically they are sand cars not race cars. People that want to drive them like race cars are prime Darwin candidates............
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I'd say my reply was correct considering the post preceeding it: "I think your imagination is getting the better of you and you haven't seen many crashed cars."
So, my response is that I've been around the block a few thousand times, and have certainly seen my share of wrecks, minor and spectacular, and have of course been in quite a few too. Who I am now is an old toothless hillbilly nobody who plays around building some stuff, but it's pretty good stuff for what it's designed for.
Yes, most of my early experiences were asphalt and high speed. Other is sand, dirt & offroad. But whatever a person is designing in a vehicle there should NEVER be any component that can easily or potentially enter the passenger compartment and injure people in a crash.
I wouldn't personally ride in that orange car without a hoop around the rear struts, at a minimum. The forward control arms could also enter seating area in a hard & fast wreck, so that's something I wouldn't want to experience either. I have no idea what powerplant is in it for top speed, and nobody said anything about sand use only.
I'm not young anymore, don't suppose I ever will be now. In the long past I've got a long list of friends: dead, injured, maimed, paralyzed or veg cases you water once a week, and many of the more serious were due to fatal design flaws, and stuff folks never imagined would happen. When you come to a wreck and the impact was so hard it tossed a 600lb V8 600 yards on impact after ripping it out of the motormounts and through the radiator support it makes you stop and think, especially if a friend was inside. Nobody would have imagined. I do imagine now, and imagine the worst that could happen in a wreck, and it pays off. I was suggesting that to others, due to the nature of the original post and topic.
For all of us, it's a matter of better safe than sorry. I'm not out for a fight or bragging rights, just don't want anybody to get hurt if they don't have to. :)
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I doubt anyone here will disagree with most of what you said there. We,as a site,IMO are more safety oriented than most any site out there. We wish to make that clear. However there is no way for a car to be "safe". There's just no such thing. There are SAFER cars though and therein lies the issue. Safety can be as much as possible with every gizmo and gadget imaginable or it can be ,and is usually, as much as the designer is willing to put in it and/or the level of safety that is acceptable to the buyer or that the buyer will even use. ALL sand cars and many ,many ,many other cars of all types COULD be made safer. Just my 2 cents.
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What does heat treating mean? It usually means "strengthened". For 4130 that means hardended and tempered.
If you were talking about heat treated aluminum, it would also mean "strengthened" but would be "solution treated and aged".
But as you mention, annealing, normalizing, aging, precipitation hardening, etc. are all heat treating processes.
Usually is something is annealed, it is not called heat treated, since it has only gone thru a softening process and has not been strengthened but rather weakened.
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I agree with that as most ,if not all, of us generally do.The thing though is that in the HT industry normalized indicates a fairly narrow range of heat treating process. Also , hardened to most of us means much harder than normalized and therefore more brittle. Along those lines along with the fact there was a well respected builder welding hardened 4130 which is a no-no no matter where you look up info on welding 4130 is just amazing to me and I have to agree that NHRA's willingness to be so lax on the certification of the chassis is just inexcusable to me.
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My apologies. I think my words often read diffferent than they get thunk on this end.
For a lot of us who hit 'middle age' things change. Like a friend said, "Id feel a whole lot better about it if I knew of more people 120 & 130!" We've seen the crazy stuff that 'could never happen' become commonplace. It happened to me.
Worked a job that included some painting, not something I normally did. Just painting some steel, no big deal. Next thing I knew I was laying in a bed paralyzed, blind and stone deaf! Company owner decided to save 5 bucks a gallon on the case of paint, and that was on a half million dollar retooling job!
It was paint only to be used on offshore oil rigs: wear a full air-tight suit, cuffs taped to gloves and booties, full hood & air fed respirator. He didn't mention that part, no MSDS available, so I used it completely unprotected, for 3 days.
Thank God, literally, I'm slowly recovering. Sight & hearing is back 100%, mobility fairly good, but I'm disabled for life. There's no treatment for it and every day is a challenge. So, I look a lot harder at safety, and try to envision the hidden dangers in anything.
Play hard guys, have fun, but be safe, please be safe.
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Sounds like Imron paint. Got a buddy with similar experience when it first came out 20 or so years ago -before anyone knew better. You might be fine the first time or even first several times but when your body said it was enough you ended up in the hospital with life threatening issues and the accumulative effect never goes away .Any further exposure of any kind will put you right back in the hospital -possibly dead .No matter,hope you get to near normal.
"Play hard guys, have fun, but be safe, please be safe." Great advise and much appreciated. On a serious note ,I will reinforce the sites POV on safety, --ALWAYS USE safety equipment and design things as well as each of us can with safety always in mind.
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I don't have any experience with welding 4130, but there is another problem that can be created. In thin wall 4130 it can actually cool fast enough in air after welding that it hardens in the heat affected zone. Care should be taken to slowly cool any welded areas on these frames. Pouring water on a hot weld or fan cooling it would only make it worse. A good practice would be to stress relieve the welded frames after welding, but there aren't many furnaces large enough to accomodate that task. If you do decide to stress relieve the frame, make sure you have all cavities of the frame vented to allow for expanding gases to escape.
All of this is of less concern if you use lower alloy grade steels with less hardenability.
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Most of us in the buggy fabbing world know of the issues of the HAZ. Careful attention to welding heat and size of HAZ is very important. IMO the worst thing that is done is the practice of welding the joints in 4 90* arcs. IMO that creates what you are referring to when welding thin wall 4130-too much heat.
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IMO the worst thing that is done is the practice of welding the joints in 4 90* arcs.
I have actually seen this suggest a lot to be done this way. B ut with nothing to back it up of course. In an odd way it seems to make sense so I think thats why it gets spoke of to do it in the 4 90* arcs. I try to go as far around a tube as I can in one shot access permitting.
But whats the best really?
EDIT: I must add that I do not use 4130 as I feel its way overhyped and actually more dangerous if done wrong. But I just use DOM tube. I DO need to go the place I get it to find out more about it (the DOM I use). Never had an issue welding it though.
Edit#2. Just called the steel supply and they said ALL thier DOM under 5 inches is 1020 steel. So thats what I am messing with.
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The weld issue is not due to too much heat, but rather too fast of a cooling rate. One continuous fillet may be better, but it doesn't relate to more or less heat. The DOM (Drawn Over Mandrel) 1020 tube doesn't have anywhere near the hardenability of the 4130, that's why it is much more forgiving. It has both low carbon and low alloy content.
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I understand that but with more heat in the tube the HAZ is greatly enlarged and in turn the area that is hardened is in the area of most needed elasticity.
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Too fast cooling is ,of course ,the key to the hardening with the higher carbon content compared to 1020 .
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There is a way to normalize a frame through electrical induction. This induction method is commonly used in industry. There a coil is energized and the magnetic field causes heat. It's possible to wire up a steel tube frame directly like an electric toaster element and achieve normalization temperature. With a sufficient power source it's fairly easy, but potentially quite dangerous as high voltage and amperage are present. You could die from it if you don't know what you're doing.
Just as in the mention of the paint escapade, insulation from harmful elements is the key. If you don't know enough about electricity to do this without help, don't try to do it alone. You could die from it if you don't know exactly what you're doing.
Nevertheless, it's possible, and eliminates the need for an oven etc. A little bit of imagination should reveal a huge power source, but that's up to you too, and equally dangerous.
Some may have an electrician friend to guide them in this process, it's actually simple, but highly dangerous if done incorrectly.
Understood if moderator chooses to delete!
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There is a way to normalize a frame through electrical induction. This induction method is commonly used in industry. There a coil is energized and the magnetic field causes heat. It's possible to wire up a steel tube frame directly like an electric toaster element and achieve normalization temperature. With a sufficient power source it's fairly easy, but potentially quite dangerous as high voltage and amperage are present. You could die from it if you don't know what you're doing.
Just as in the mention of the paint escapade, insulation from harmful elements is the key. If you don't know enough about electricity to do this without help, don't try to do it alone. You could die from it if you don't know exactly what you're doing.
Nevertheless, it's possible, and eliminates the need for an oven etc. A little bit of imagination should reveal a huge power source, but that's up to you too, and equally dangerous.
Some may have an electrician friend to guide them in this process, it's actually simple, but highly dangerous if done incorrectly.
Understood if moderator chooses to delete!
Don't try this at home kids!
(Disclaimer added)
;D
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Aww heck, go ahead and try it at home. Claims adjusters and morticians need work too!
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There is a way to normalize a frame through electrical induction. This induction method is commonly used in industry. There a coil is energized and the magnetic field causes heat. It's possible to wire up a steel tube frame directly like an electric toaster element and achieve normalization temperature. With a sufficient power source it's fairly easy, but potentially quite dangerous as high voltage and amperage are present. You could die from it if you don't know what you're doing.
Just as in the mention of the paint escapade, insulation from harmful elements is the key. If you don't know enough about electricity to do this without help, don't try to do it alone. You could die from it if you don't know exactly what you're doing.
Nevertheless, it's possible, and eliminates the need for an oven etc. A little bit of imagination should reveal a huge power source, but that's up to you too, and equally dangerous.
Some may have an electrician friend to guide them in this process, it's actually simple, but highly dangerous if done incorrectly.
Understood if moderator chooses to delete!
By all means be sure to take a friend out at the same time! rofl nono
It's highly dangerous rigged up period. nono
Mod says do not try this.
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I needed a laugh tonite i guess.
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And there we go there now!
I'll probably do it on my next chassis if it seems necessary. Like I mentioned, I design stuff that it could be built out of northwestern cedar or Sitka spruce, the amazingly tough stuff they made masts, spars & yardarms out of. That way a chassis design is structurally real tough when done in steel. Probably not necessary to normalize using DOM cold rolled which I bought for this one.
I know some might be scratching their heads on the reference to those woods, but do some research on their relative strength even compared to steel and it's real surprising. It's the perfect monocoque design within itself!
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If you do this, please take video, I'd love to see it. How do you control the cooling rate afterwards (which is critical for normalizing)? How do you control max temperature?
In your description, I don't think this would actually be called induction heating, but more likely resistance heating, which is much different.
Induction heating is very common in the heat treating industry. Are you saying this type of normalizing procedure (let's call it the Frankenstein method) is common for frame builders???? bs1
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And there we go there now!
I'll probably do it on my next chassis if it seems necessary. Like I mentioned, I design stuff that it could be built out of northwestern cedar or Sitka spruce, the amazingly tough stuff they made masts, spars & yardarms out of. That way a chassis design is structurally real tough when done in steel. Probably not necessary to normalize using DOM cold rolled which I bought for this one.
I know some might be scratching their heads on the reference to those woods, but do some research on their relative strength even compared to steel and it's real surprising. It's the perfect monocoque design within itself!
I have sold lumber all my life pretty much and i'll agree you COULD build a buggy from those woods. You a friend of Howard Hughes by chance? But comparing a design sufficient to use woods for the frame/mono/whatever to a frame of steel is a bit ludicrous when it comes to actual chassis design comparision of wood vs steel. Gawd,this has been entertaining!
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And there we go there now!
I'll probably do it on my next chassis if it seems necessary. Like I mentioned, I design stuff that it could be built out of northwestern cedar or Sitka spruce, the amazingly tough stuff they made masts, spars & yardarms out of. That way a chassis design is structurally real tough when done in steel. Probably not necessary to normalize using DOM cold rolled which I bought for this one.
I know some might be scratching their heads on the reference to those woods, but do some research on their relative strength even compared to steel and it's real surprising. It's the perfect monocoque design within itself!
IF it seems necessary? If it's needed ,it's needed regardless of design. Make up your mind. Either you feel it's needed or not. Besides i want to see the vids myself!
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A bit off topic, but my friend's son is just getting into heat treating furnace sales, so I thought we'd have him load/unload a few furnaces (started off small/easy). If you click on the photo below it should show a short video.
Pat
(https://dtsfab.com/proxy.php?request=http%3A%2F%2Fwww.smugmug.com%2Fphotos%2F775820828_ytTdL-M.jpg&hash=d634a63a3b3953f7e62be6b0e32aa5693a6bff4d) (http://www.smugmug.com/gallery/8478986_HFrmT#775820828_ytTdL-A-LB)
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Nothing says excitement like fire!
I have been looking at this for a long time for chassis.
http://www.meta-lax.com/ (http://www.meta-lax.com/)
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IF it seems necessary? If it's needed ,it's needed regardless of design. Make up your mind. Either you feel it's needed or not. Besides i want to see the vids myself!
Yeah, I know. But this one will be a tame thing for easy going on street & trails, so not subject to huge stresses. Best to HT though.
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Nothing says excitement like fire!
I have been looking at this for a long time for chassis.
http://www.meta-lax.com/ (http://www.meta-lax.com/)
Same here,but IMO,we're getting carried away. The question is,is it necessary or just a talking/selling point?
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Hi guys!
I don't want to post any details at all regarding a method for inductance, or as mentioned more correctly, resistance heating, due to personal liability issues, sorry. Just brought it up as a possibility for those who are able.
And regarding the frame and thinking wood design while designing, that's a generalization of planning distribution of loads, that if it would work in wood it will work in steel to have sufficient strength. Speaking of tension and compression loading.
Anyways, I was just tossing it all out there for chit-chat so apologies if it all sounded like a bunch of chit, but we did chat!
Have a GREAT week! :)
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If you do this, please take video, I'd love to see it. How do you control the cooling rate afterwards (which is critical for normalizing)? How do you control max temperature?
In your description, I don't think this would actually be called induction heating, but more likely resistance heating, which is much different.
Induction heating is very common in the heat treating industry. Are you saying this type of normalizing procedure (let's call it the Frankenstein method) is common for frame builders???? bs1
It sounds like he is basically taking an oven element and wrappping it around the chassis, rather than passing the current through the chassis. You would control the max temp and cooldown thre same way as you would with an oven - thermostatic control of the amperage.
Edit: Whoops, he did mean resistance heat treating. Oh well, same control methods I guess?
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i don't think you understand heat treating basics guys.