Upgraded trailer suspension

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This is on my little single axle 16 foot rv trailer. First pic is what it came with from the factory, a 3/16" "U" type bracket welded to the frame, then a couple pieces of flatbar for the shackle.  There were no bushings on this thing, just the bolt going through the steel pieces, and there was a whole lot of slop. Second is the new shackle mount with a quarter inch spacer, and third is with the new shackles with greasable bolts.  Not to much welding, but I feel a whole lot safer on the road now. Attached Images
Reply:No offence, you may feel safer, but I don't! Those welds look cold. My guess is they were made with a small 110v mig (small cold looking welds like this are typical of small migs) I'd almost be willing to bet I could break those welds loose with a 10 lb sledge if they were only welded on one side. They don't look like they were burned into the base steel like the welds on the bushing plate do. ( I see some issues there as well ) Catch a wheel on a curb or pothole at speed and they may tear off the frame.I'd stongly suggest you get those redone properly for everyones safety. Road trailers are not good items for people to learn to weld on..No government ever voluntarily reduces itself in size. Government programs, once launched, never disappear. Actually, a government bureau is the nearest thing to eternal life we'll ever see on this earth! Ronald Reagan
Reply:I entirely agree with DSW!From my non-professional point of view, the welds in the last photo do not have deep enough penetration for what they are. remember, enormous amounts of energy and force are transmitted by the four spring shackles. not something to skimp on!they probably will hold, but for piece of mind, I would grind them off and do it again.
Reply:The way you have the eye welded to the pad in your first pic looks likely to develop a fatigue crack, starting where your weld ends near the eye, and propagating along the weld.I agree with Doug, some of the welds look cold with lack of fusion.
Reply:Thank you guys for the responses, while I feel the welds to the frame are stronger than what was on there(I think the "U" bracket was just 3/16'' x 1 1/2 flatbar), I will be grinding them out.  As for the eye what would have been a better way to weld it, I was told by the place I bought them from, weld to that point and stop, I was thinking the same thing, as to not have any cross welds on the frame.
Reply:That looks an awful lot like a chunk of leaf spring.  That ain't good.My name's not Jim....
Reply:We normally see those heavy duty links on multi-axle trailers, and yes, they are much more durable than stock shackle links. I know what people say about cross welding frames, but Dexter recommends welding across the front and rear edges and wrapping the around the side corner by 3/4" on front spring hangers. The center portion of the sides are optional. The small rear hangers get welded all around.See page 13.http://i.b5z.net/i/u/1080235/f/Appli...te_Catalog.pdfThose greasable hangers are weldable, even though they look like cut springs.Last edited by tanglediver; 03-13-2011 at 04:24 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:That looks an awful lot like a chunk of leaf spring. That ain't good.
Reply:the weld in foto 2  to the spacer pad does not look near as cold as the 3rd foto welded to the flange.. i wonder if being out of position afected travel speed and didnt let the flange heat up.. the 2nd foto i assume was done flat...also looks like no grinding off the paint on the flange, which will not help a thing.
Reply:Originally Posted by BoostinjdmThat looks an awful lot like a chunk of leaf spring.  That ain't good.
Reply:Originally Posted by BoostinjdmThat looks an awful lot like a chunk of leaf spring.  That ain't good.
Reply:tanglediver, thanks for the info. After the snow melts, the welds to the frame will be fixed.  As for the shackle eye, it isn't a cut spring, just rolled mild steel. Has anyone used these eyes before, and if so how was it welded, cause I was just doing what the guy told me at the shop.
Reply:Forgive me if I'm being obtuse, but what do people say about "cross welding frames?"
Reply:Originally Posted by ncfhForgive me if I'm being obtuse, but what do people say about "cross welding frames?"
Reply:Originally Posted by homegrownrmktanglediver, thanks for the info. After the snow melts, the welds to the frame will be fixed.  As for the shackle eye, it isn't a cut spring, just rolled mild steel. Has anyone used these eyes before, and if so how was it welded, cause I was just doing what the guy told me at the shop.
Reply:Here is my shackle set up. Made a vid of it. I cannot believe the way factory trailers are made. Flame cut holes and no bushings.[ame="http://www.youtube.com/watch?v=DtI2fx4V2dY"]http://www.youtube.com/watch?v=DtI2fx4V2dY[/ame]www.tjsperformance.comDynasty 300 DXHTP 240HTP Microcut 380Hyperthem 85JD2 Hyd Bender and HF Hyd Ring Roller all in one =(Frankenbender)Bpt. Mill/DRO4' x 8' CNC Plasma TableInstagram: tjsperformanceYT: TJS Welding and Fabrication
Reply:Originally Posted by TJSHere is my shackle set up. Made a vid of it. I cannot believe the way factory trailers are made. Flame cut holes and no bushings.
Reply:LOL. That is why I picked it. The trailer WAS falling to pieces. Not any more.T.J.www.tjsperformance.comDynasty 300 DXHTP 240HTP Microcut 380Hyperthem 85JD2 Hyd Bender and HF Hyd Ring Roller all in one =(Frankenbender)Bpt. Mill/DRO4' x 8' CNC Plasma TableInstagram: tjsperformanceYT: TJS Welding and Fabrication
Reply:Ok, as far as those hangers go... i have used hundreds of them. Stopping the weld at that point is important so that the shackles don't bind on the weld. If the shackle isn't moving freely all of the trailer weight will be transfered dirrectly to the spring. The shackles standing straight up will produce the same effect. (picture 3)Last edited by Rkott4; 03-14-2011 at 09:14 PM.
Reply:Originally Posted by Rkott4 If the shackle isn't moving freely all of the trailer weight will be transfered dirrectly to the spring. The shackles standing straight up will produce the same effect. (picture 3)
Reply:Originally Posted by popeye865 ughhh seems to me all the trailer weight is transferred to the spring no matter the shackle angle
Reply:Originally Posted by Pro-FabThe shackle eye is fine. You have made a very common mistake by not filling in the crater at the end of your weld by the eye. this hollow pocket is a place for a crack to start, and if the material was anything other than mild steel, it might have already. Once a crack starts, it will gradually travel the full length of your weld.
Reply:Originally Posted by roadkillbobbwhy wouldnt welding around the eye be stronger? it looks like only the thickness of the metal is offering strength and could bend down because to eye end is not welded....is that code or manufactures recomondation?
Reply:Originally Posted by Pro-FabThe idea is to let it flex. Any time you make a structure too stiff to give a little under load, it will develope cracking.That is why cracks always develope where there are weldments that create stiffness to a member. Poorly designed frames that are not properly gusseted will always fail eventually.
Reply:Originally Posted by BoostinjdmYou want them angled slightly past center so they move in the right direction when a load is applied.  If you mount them straight up then they can "balance" there until nudged one way or the other.  When "nudged" the wrong way, you could possibly break something because the spring won't allow any give.  Hope you follow.  Kinda struggled wording that.Ever get a shackle rocked the wrong way with a load on you'll learn to wrack them slightly in the direction you want them to always go. Rough terrain, ditches, curbs & rocks and especially while backing up a single axle in less than ideal conditions can make a believer out of you quick. They ain't easy to get popped back out while the load is still on there. If you never get off the hi-way maybe it doesn't matter."The things that will destroy America are prosperity at any price, peace at any price, safety first instead of duty first, the love of soft living and the get rich quick theory of life." -Theodore Roosevelt
Reply:I think what Boostinjdm was saying is that you don't want the shackle flipping forward so it should be biased slightly rearward.....Mike
Reply:All the posting about the angle of thge shackles got me worried, so I went to take a look under there.  I forgot that the trailer weight was all on the stabilizers when I took the pics, and the shackles are dam near vertical.  With the weight resting on the axle, I do remember that they are angled past center in the right way.  The eye pad is welded to the frame on all four sides, and looks 100 times better in person, but it will be ground down, and rewelded.  I have a syncrowave 180(think it's the 180) so I'll put some more heat to it.
Reply:Originally Posted by homegrownrmkAll the posting about the angle of thge shackles got me worried, so I went to take a look under there.  I forgot that the trailer weight was all on the stabilizers when I took the pics, and the shackles are dam near vertical.  With the weight resting on the axle, I do remember that they are angled past center in the right way.  The eye pad is welded to the frame on all four sides, and looks 100 times better in person, but it will be ground down, and rewelded.  I have a syncrowave 180(think it's the 180) so I'll put some more heat to it.
Reply:Originally Posted by SandyEver get a shackle rocked the wrong way with a load on you'll learn to wrack them slightly in the direction you want them to always go. Rough terrain, ditches, curbs & rocks and especially while backing up a single axle in less than ideal conditions can make a believer out of you quick. They ain't easy to get popped back out while the load is still on there. If you never get off the hi-way maybe it doesn't matter.