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So the practice project I chose was one I screwed up before, a drop/rise hitch mount.YUK!!!  ~~~~~~~~~~~~I got the whole miter cut theory ok, prep work is good.I can even make a tig weld!  (I need lots of practice!)The biggest thing I learned from yet another hitch mount is that I need to start clamping all these parts in some kind of JIG. Heat shrinkage put a tweek into the final product that I need to account for in the future. Sorry I ran out of film, no more of the final finish.City of L.A. Structural; Manual & Semi-Automatic;"Surely there is a mine for silver, and a place where gold is refined. Iron is taken from the earth, and copper is smelted from ore."Job 28:1,2Lincoln, Miller, Victor & ISV BibleDanny
Reply:Nice stuff Dan. Er, the new one that is  Hey, as nice as the welds are and all that, I am still gonna suggest plates on the sides. Better safe than a run-a-way boat, eh? .....
Reply:Man that looks great, I bet your going to do maybe a couple more passes.Look better than the first actually not even in the same book....or library weld it like you own it
Reply:No worries TEK. Gussets are cool, and a good idea. If anything, this will first get tested by forklift in the yard and it will really only get used on little trailers. Actually I don't even have a trailer with a pintle ring at the moment!  I may one day put all my spare parts into a small O.R. utility trailer.Yup Lewray, I made several passes after the root. The ends were beveled first to get nearly full penetration. I needed a good excuse for a required personal project in class. It seemed to fit the bill. I will get more film in the camera and reply when they are developed.City of L.A. Structural; Manual & Semi-Automatic;"Surely there is a mine for silver, and a place where gold is refined. Iron is taken from the earth, and copper is smelted from ore."Job 28:1,2Lincoln, Miller, Victor & ISV BibleDanny
Reply:Originally Posted by TEKNice stuff Dan. Er, the new one that is  Hey, as nice as the welds are and all that, I am still gonna suggest plates on the sides. Better safe than a run-a-way boat, eh? .....
Reply:Tack 4 corners before welding and you shouldn't need clamps.  Nice Tig welds. Good layout skills.DavidReal world weldin.  When I grow up I want to be a tig weldor.
Reply:Yeah the second one is a major improvement good work.Will   Supports Autism Awareness                            My ToysBobCat 225 PLusMillermatic 130Miller Spectrum 300 CutmateEverlast Power Tig 185 Micro April is Autism Month .
Reply:if you tack them up real good tig them they shouldnt warp on you, looks like your just fusing them. add some filler rod and it will cool the weld down and the heat zone will be smaller. looks good though so far.
Reply:It's been a few days since I started this project......but as times change, I found my way back to it. This was its first use.I had no doubt that it would hold together, and it did just fine, (with an empty trailer). But, as we discussed, it can still be improved.I gave it a Mohawk. Pics... Attached ImagesCity of L.A. Structural; Manual & Semi-Automatic;"Surely there is a mine for silver, and a place where gold is refined. Iron is taken from the earth, and copper is smelted from ore."Job 28:1,2Lincoln, Miller, Victor & ISV BibleDanny
Reply:Personally, I hate receiver hitches.  Too much leverage due to the extension beyond the bumper/rear plate.  Most commercial designs have no bracing behind the bumper to tie it into the frame, or resist downward twist.  The actual hitch piece may be strong, but they're generally not anchored properly in the socket area.The strongback ought to go a long way towards reinforcing the tubing.As a rule, it's generally considered bad form to place a strongback in the center of the tubing without a tie in to the shoulder to carry the stress to the  web.  Relying on the top of the tubing to transfer the stress is usually not a good idea.  The top will buckle/deform.The stuff you're working with looks pretty thick.  Pretty healthy thickness on the tubing.  So the strongback will definitely add strength.  And it's on the right side of the tubing!!!!!  It's in tension, not compression.  I see a lot of guys put it on the wrong side where it's in compression.It looks like you gapped the joints, then welded.  Nice full penetration weld.  I don't think I'd add fishplates either in this case.  If the weld is good, the tubing is as strong as if it were a solid piece unbroken by the joints.  The stronback will go a long way in counteracting any stress raisers along the edge of the tube welds.  Not so much flexing.I'm convinced it couldn't have been done any better than you did it.  I'd have extended the strongback clear to the bumper, but it may not be necessary. The real area of concern is always where the tubing changes direction.  The only benefit would have been a longer weld to tie it into the straight piece going into the receiver.You'll be second guessed till the cows come home  If it works, it's cool.I just don't like the extension on the typical receiver hitch, and it's probably a stupid concern.  Sure do see a ton of them on the road."Any day above ground is a good day"http://www.farmersamm.com/
Reply:Sam,  I don't like how far receivers stick out either.  Not sure I understand your "Most commercial designs have no bracing behind the bumper to tie it into the frame, or resist downward twist." comment.  Other than the cheesy $20 bumper mount receivers, they all have fairly hefty mounts directly to the truck frame.  I've seen a crane dangle a truck by the hitch before.  People towing from the bumper scare the hell out of me....My name's not Jim....
Reply:From the first test fitup, I knew that I had to redrill for the hitchpin because my chains were too short.  That is why there is a second hole in the shank. The new location is better. The strong back will help, but I can still add some strain relief between it and the sideweb of the tube as Sam was thinking, but that can wait for the moment. It is coming together. Attached ImagesCity of L.A. Structural; Manual & Semi-Automatic;"Surely there is a mine for silver, and a place where gold is refined. Iron is taken from the earth, and copper is smelted from ore."Job 28:1,2Lincoln, Miller, Victor & ISV BibleDanny
Reply:Very nice work, Danny.  This may come off rather picky and probly won't end up being an issue in actual use, but, from a theoretical standpoint, I would have drilled the second hitch pin hole a little further forward so the edge of the reciever tube doesn't come to right where the weld joint is.  The greatest stress on the hitch bar is at the location of the hitch pin and at the end of the reciever tube, which in this case appears to be making contact right at the toe line of the weld, where the welded joint is weakest.  Moving the pin hole forward an inch would keep that contact point out of the heat affected zone area of the weld.  Again, probly nothing will fail because of it, but since we were talking about the theoretical ramifications of different placements or designs of the gusset, I thought I would mention this too.I know you said you were planning to use it for light trailers.  Now I see it connected to a trailer that looks to be pretty heavily built.  Reciever ball mounts for trailers 8K lbs and over are normally made from 2" solid bar, rather than 2x2x1/4 square tube.  Square tube ball mounts usually stop being used about the 7K lb rating mark.  Be careful what you tow with your tube mount.Last edited by DesertRider33; 06-26-2010 at 10:03 AM.MM350P/Python/Q300MM175/Q300DialarcHFHTP MIG200PowCon300SMHypertherm380ThermalArc185Purox oaF350CrewCab4x4LoadNGo utilitybedBobcat250XMT304/Optima/SpoolmaticSuitcase12RC/Q300Suitcase8RC/Q400Passport/Q300Smith op
Reply:I agree with Desert,Solid Draw Bar for that weight unless this is only used to Tow the trailer unloaded.Adjustable Pintle Hook Plates are made with a Solid Draw bar welded to a Plate with Holes to move the Hook up or down.Ed Conleyhttp://www.screamingbroccoli.com/MM252MM211 (Sold)Passport Plus & Spool gunLincoln SP135 Plus- (Gone to a good home)Klutch 120v Plasma cutterSO 2020 benderBeer in the fridge
Reply:Hmmm. Good points, and I appreciate your views. Thanks. The straight mount on the table is actually a solid bar and I would have preferred to use it, but I am looking to level the ride. I can get a solid adjustable pintle mount from work if need be $$. The trailer rides on a 7K single axle, and is still a work in progress so...Last edited by tanglediver; 06-27-2010 at 02:34 AM.City of L.A. Structural; Manual & Semi-Automatic;"Surely there is a mine for silver, and a place where gold is refined. Iron is taken from the earth, and copper is smelted from ore."Job 28:1,2Lincoln, Miller, Victor & ISV BibleDanny
Reply:Ok, I gotta ask.....Why would you go with a pintle hitch on a 7K trailer?My name's not Jim....
Reply:They handle rough terrain better.City of L.A. Structural; Manual & Semi-Automatic;"Surely there is a mine for silver, and a place where gold is refined. Iron is taken from the earth, and copper is smelted from ore."Job 28:1,2Lincoln, Miller, Victor & ISV BibleDanny