Where to get a hinge?

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I want to build a rear bumper/spare tire carrier for my jeep. The tire carrier portion will pivot on one end of the bumper and will hold my hi-lift jack as well as the spare. The problem is that I have no idea where to get a hinge that will support that kind of weight. I know they  make them because I can buy the bumper already made but that's no fun. Any ideas on where I might find a hinge like that?Brand new Lincoln Electric Pro-Core 100 wire feed welder. Still learning to make anything that might resemble a bead.
Reply:If you are going to build the bumper and tire carrier why not fabricate the hinge  using some  1/4 wall bushing stock and shafting  to fit, just dont get the fit too tight or you will have rusting problems and a tight or frozen hinge joint. or if you do not have access to the materials  mentioned you can  use a pipe in a pipe  a 1 inch pipe inside a 1 1/4 pipe makes a pertty good and cheap hinge.Good luck:J.W.
Reply:You can purchase "weld on " hinges.  They are clean and the better ones are bronze bushed.  Most welding suppliers have some in stock or know where to pick them up.  They come with pins 1/4 inch diameter at the smallest.  I have seen these units with 3/4 pins also.
Reply:Lookie here. http://www.kingmetals.com/Pages/Page25-5.htmlI'm not a Engineer, I just play one on the weekend.
Reply:IBLEED, I'm planing in fabricaring a tire carrier for my CJ5 I'm going to use the hinge this kit http://www.rockstomper.com/catalog/pieces/hinge.htm.I have heard that using a pipe inside another pipe is not a wise idea. Post some pic when you get finish with the project.
Reply:Originally Posted by LuisIBLEED, I'm planing in fabricaring a tire carrier for my CJ5 I'm going to use the hinge this kit http://www.rockstomper.com/catalog/pieces/hinge.htm.I have heard that using a pipe inside another pipe is not a wise idea. Post some pic when you get finish with the project.
Reply:The failed spindle on that tire carrier is a brittle fracture.  Why anyone would weld on a spindle is a mystery to me.  It is at least a medium carbon steel and would be extremely brittle after welding.If the person had used a grade five bolt he would have had much better luck.  A soft steel bolt would have bent and twisted in every direction before fracturing.  If you also look at the weld one will notice it was cold and lacked fusion in places.The best way to avoid these kind of problems is to not weld on any bolts or fitting unless they are intended for welding.  A creative design can use short pieces of flat bar with corresponding holes drilled in them.  You put a bolt through the matching holes and use a self locking nut so that you can adjust the friction and prevent loosening.It is educational to note that the ugly weld did not fail.  It was strong enough.  What caused the failure was the use of incorrect material.
Reply:Lotechman, some of these stub axles are designed to be welded to axle tubes.  The spindle in the kit I am using is one of them.  See:http://www.northerntool.com/webapp/w...17&R=200314617.  However, that doesn't mean that the people in the thread I linked before used one of them.Also, the spindle at Northern Tool says it has to be properly welded.  I'm still new to welding and have never welded on trailers before, so I don't know what the proper procedure/process is that they are refering to, I'm still researching it Last edited by Juiceman72; 09-01-2005 at 02:41 PM.
Reply:Generally in structural steel once the material goes over 3/4 inch it will be preheated before welding.  Some shops don't require preheat until one inch thick.  The preheat does not have to be much.  200 F is good enough for mild steels.  The key thing to understand is that by preheating the cooling rate after welding is slowed.  The preheating also helps with fusion to the parent metal.  I looked at the one example of a kit that can be welded.  It appeared to me that if one was not careful about how one welded on the tube the tube would distort.  Since there would be an antifriction bearing inside it could bind.  A nice way to avoid these problems is to cut a hole in the upper and lower wall of a horizontal tube then run the hinge tube through the structural tube.  Now all you have to do is weld around the hinge tube to seal it in where it pierces the horizontal tube.  This way there is no stress on the weld and the horizontal tube has to be totally destroyed before the hinge tube would tear away.When you make something think about putting the welds where they will have the least stress.
Reply:I did read the thread mention, I believe that the failure was caused by the welding not the material. The set up that you mention sounds like a better option, definitely I will use that set up (a piece of mind). I'm not; by any means a good welder for this part of the project I will let someone with experience do the welding. I will be doing the rest the fabrication my self. Where are you getting the plans from? Are you going to built it with the option to carry a gas can and a jack?
Reply:I've been looking at a bunch of designs on the internet and have been trying to put everything I like into my design.  It's not finalized, however.  I'm still learning when it comes to welding, so I've just been gathering information and some misc. parts.  I've got some other projects lined up that will hopefully improve my skill level before I try and tackle this one.I intend on carrying my 33" spare and a hi-lift jack on the carrier.  My Jeep is a '93 Wrangler with a 4.0L (20 gal tank).  It gets ok milage on the trail and where I wheel typically doesn't require me to bring extra gas as long as I fill up at camp.I like what lotechman has to say about putting the hinge tube inside of the rect tubing for the carrier.  However that would require at least 3" square tubing to be used for the carrier, I was originally planning on using 2" square.  And the only other issue would be dealing with the zerk fitting for greasing the unit.  I'll need to take a look at the weight differences in the end to determine which material I will end up using.  The bumper itself will probably be 3" x 4" rect tubing, tapered on the ends in two planes, similar to some of the bumpers that Warn makes.As a side note, I had considered one of these for the hinge.  It would have been nice because you could mount it on the top of the bumper, and the bolt would be in double-shear.  I ordered one, and to my dismay there is too much play in the bearing.  I want my carrier's operation to be smooth with no sagging.  Obviously these were designed to be paired up on heavy steel gates.
Reply:That failure was not the weld even as small and cold as it was.  The fracture happened next to the weld bead.  This area is called the Heat Affected Zone ( HAZ) and is the common failure area.  the fracture is right through the shaft.  If the weld had failed we would have seen the end of finished shaft and chunks of weld material sticking to the shaft and chuncks sticking to the bumper.    Steel is an alloy of carbon and iron.  The carbon can run from 0.1 percent to over 4 %which is cast iron.   When you heat steel to its critical temperature ( cherry red) then quench it rapidly you trap the carbon atoms in the crystaline structure.  This increases strength but makes it brittle.  When you weld on a large piece of steel the HAZ reaches this critical temp. then the massive amount of surrounding steel draws the heat away rapidly causing the area to be hardened.  There can be so much stress built up that cracks can occur a day or two after welding.
Reply:That failure was not the weld even as small and cold as it was.  The fracture happened next to the weld bead.  This area is called the Heat Affected Zone ( HAZ) and is the common failure area.  the fracture is right through the shaft.  If the weld had failed we would have seen the end of finished shaft and chunks of weld material sticking to the shaft and chunks sticking to the bumper.    Steel is an alloy of carbon and iron.  The carbon can run from 0.1 percent to over 4 %which is cast iron.   When you heat steel to its critical temperature ( cherry red) then quench it rapidly you trap the carbon atoms in the crystalline structure.  This increases strength but makes it brittle.  When you weld on a large piece of steel the HAZ reaches this critical temp. then the massive amount of surrounding steel draws the heat away rapidly causing the area to be hardened.  There can be so much stress built up that cracks can occur a day or two after welding.    The smaller the weld size compared to the thickness of material the greater this problem.  If you are welding with a wire feed unit running .035 wire you are limited in weld size per pass.  The solution is to preheat!  Use multiple passes, Cool as slowly as possible, consider post heating to reduce cooling rate further.    Otherwise things will break in the HAZ.
Reply:Excellent info lotechman, thanks!  I really enjoy this site and the Hobart site as well, lots of good info.I plan on doing a front bumper first, I'll post some pics and a writeup of what I did for critiquing when I'm finished.
Reply:I replace spindles on peanut wagons here every year,  the count as of today is 160 since June.  I have probably done over 3000 in my life.  These spindles are on trailers that when loaded weigh as much as 30,000 pounds.  I have never had one fail.  Lotechman is right in his info as far as controlling the cooling.  I will bet you anything that the spindle in that picture was cooled with water after it was welded.  However I will say that I think using a 1000 pound spindle for a carrier rack is over design.  I would suggest talking to a local machine shop.  I have made alot of hinges that would work for your needs out of heavy wall seamless tubing and cold roll.  Install a grease fitting in the tube and you will be fine.  Most machines shops will have a scrap pile that I guarantee would have something you could use.  Good luck  ~JacksonI'm a Lover, Fighter, Wild horse Rider, and a pretty good welding man......
Reply:I remember once I was having a deer stand welded. It was steel, weighed a ton and I was young. But that's another story. Anyway when he finished I was impatient and dunked the thing in a trough of water to cool it down. He said I shouldnt have done that because it makes the metal brittle. I blew it off thinking "hey it's steel, steel is strong". But ever since I tried to weld some cast iron( which didn't work worth a durn), I've been studying on the matter. Point is, like was mentioned earlier, those little steel molicule thingies have to align in a state that makes steel, steel. If they cool too fast it's not good. It ends up in a state that "real" steel, molecular scientist types have nightmares about. In the end, as a practice, when ever I weld something that is load bearing, I let it cool naturally, so as to no take any chances.I'm not a Engineer, I just play one on the weekend.
Reply:Hey guys, quick question.  I was wondering what temperature the spindle should be heated up to?  Could it be done in a conventional oven, or should it be done with a torch?Thanks,Justin
Reply:You can heat it with torch to a dull red before welding.  Honestly the last two years I have not preheated spindles.  Some may disagree with that, but I have not seen a difference.    However, i will say that controlling the cooling down is essential.  if you can pack the piece in sand or   a little post heat at times will help keep it from cooling to fast.  ~JacksonI'm a Lover, Fighter, Wild horse Rider, and a pretty good welding man......