Semi trailer landing gear.

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On some semi trailers the landing gear is designed to hold a loaded trailer. Well, I kinda thought I migh have a problem but one of my best customers needed a machine moved and I was already preloaded for an early start. So I dropped the dump trailer loaded, so I could hook up to a lowboy. When I was done I had to use a floor jack to get the inner leg up into the outer leg. I new I was going to have to replace it. These "static" (non-cranking) landing legs usually don't do well with a load on. Well tomorrow I have to move a machine for the same customer and so today the rush was on to replace it, after work.I welded a 1/4" plate to the frame web just in case I ever have to do this again. I don't want to keep heating the frame.Then I used 6" channel. "Where's Stick man????????" - 7A749"SHHHHHH!! I sent him over to snag that MIC-4 while tbone wasn't looking!" - duaneb55"I have bought a few of Tbone's things unlike Stick-Man who helps himself" - TozziWelding"Stick-man"
Reply:All welds were done from this. ER70S-6 .045 190ipm @ 21.5V 75/25 AR/CO2First, a vert up to really burn into the tube and channel. Then a vert down for my second pass. (also with sufficient penetration) Outer tube is 4"sq. x 1/4" wall and inner is 3" sq. x 1/4" wall.And the finished product."Where's Stick man????????" - 7A749"SHHHHHH!! I sent him over to snag that MIC-4 while tbone wasn't looking!" - duaneb55"I have bought a few of Tbone's things unlike Stick-Man who helps himself" - TozziWelding"Stick-man"
Reply:Nice workmanship Stic-man.Thanks for posting it.I do have a thought about the design; you'll have to decide if it's relevant or not to the trailer's expected use. Sure the 1/4 plate is welded to the frame's web with an excellent connection, however, the attachment is some distance from where the landing gear is welded to the 1/4' plate. This design essentially leaves the gear anchored to just 1/4" flat plate. I believe that under certain abusive conditions which a dump trailer can encounter (such as "jamming" a sunken and loaded trailer while trying to connect) the forces could "peel" the 1/4" plate away from the frame, resulting in the landing gear folding in. Of course the diagonal braces would help a lot, but often they are bent or cracked.My two cents is that if such heavy abuse is possible, a few through bolts or plug welds should be considered.But then there's also something to be said about creating a concentrated too rigid repair to a trailer's frame, so maybe not.Good LuckLast edited by denrep; 09-27-2010 at 09:36 PM.
Reply:Nice, Looks great.
Reply:Originally Posted by denrepNice workmanship Stic-man.Thanks for posting it.I do have a thought about the design; you'll have to decide if it's relevant or not to the trailer's expected use. Sure the 1/4 plate is welded to the frame's web with an excellent connection, however, the attachment is some distance from where the landing gear is welded to the 1/4' plate. This design essentially leaves the gear anchored to just 1/4" flat plate. I believe that under certain abusive conditions which a dump trailer can encounter (such as "jamming" a sunken and loaded trailer while trying to connect) the forces could "peel" the 1/4" plate away from the frame, resulting in the landing gear folding in. Of course the diagonal braces would help a lot, but often they are bent or cracked.My two cents is that if such heavy abuse is possible, a few through bolts or plug welds should be considered.But then there's also something to be said about creating a concentrated too rigid repair to a trailer's frame, so maybe not.Good Luck
Reply:Nice looking welds, great picsI would put some plug welds along the sides of the channel spacers and a few above it to help transfer the load to the frame itself.My only concern is that you may have created a stress riser by welding "across" the trailer frame with the continuous weld bead.  I was taught to avoid doing this as it may lead to a crack in the trailer frame occuring here.  Short spaced skip welds would have been preferable if it is necessary to weld here.  The continuous welds top and bottom parallel to the frame should not be a problem.thanks for posting this here."The reason we are here is that we are not all there"SA 200Idealarc TM 300 300MM 200MM 25130a SpoolgunPrecision Tig 375Invertec V350 ProSC-32 CS 12 Wire FeederOxweld/Purox O/AArcAirHypertherm Powermax 85LN25
Reply:I'm no expert... but we used to have a truck manufacturing facility in town, and I have talked to some people who were supposedly experts in the field...and as far as I can recall ANY welding on the frame pretty muck makes it non road worthy.... everything in that plant was bolted to the frame rails with some pretty big fasteners... I have also heard talk that torch cut holes for the mounting is unacceptable as well, drill or water jet only... but then again I thought my alpahabits were trying to scare me until I noticed I had a box of cheerios ...lolNever argue with an idiot. They drag you down to their level, then beat you with years of experience.
Reply:I too have always been tought, "never weld to a frame rail or drill to a flange". However, I was also told that this type of frame rail is not heat treated as in a truck or truck tractor frame rail. Thats why just to the right of my ground clamp is a reinforcing plate above the suspension welded to the frame. Also the reason I did this is because I have seen quite a few done this way and one of them I know was done by a very reputable shop. And this is a dump trailer so the load is not placed directly onto the frame. The dump body has a channel frame of its own so the weight is very distributed. Now, I am not claiming to be an expert, just telling you my reasons."Where's Stick man????????" - 7A749"SHHHHHH!! I sent him over to snag that MIC-4 while tbone wasn't looking!" - duaneb55"I have bought a few of Tbone's things unlike Stick-Man who helps himself" - TozziWelding"Stick-man"
Reply:Originally Posted by pandinusas far as I can recall ANY welding on the frame pretty much makes it non road worthy.... I have also heard talk that torch cut holes for the mounting is unacceptable as well, drill or water jet only...
Reply:After re-reading the thread, I thought of something else...Now I am not sure if your binding issue is due to rusting and a build up of road grime between the tubes, or if your inner tube has filled with water and swelled when the water froze but I have a couple of ideas to make those legs work a little easier since you are the only driver, and these tips will directly benefit YOU.If you have the ways and means to lift the trailer high enough, I would pull the lower tubes out periodically (Once or Twice a year) to steam clean all the garbage out.If you find the inner tubing to be swelled or bent - replace it. (I know - "DUH")If the inner tube looks good, drill some drain holes at the bottom where the tube meets the foot pad, so that any water entering the lower tube throught the pin holes can drain. (Sleeving each hole is nice, but time consuming)Liberally coat with WD-40, or Fluid Film, then re-install.I found that if I sprayed this type of leg after pinning up to the trailer, and before I telescoped them, that it greatly prolonged the time between incidents involving Cussing, and using a BFH.Later,Jason
Reply:I have found anti-seize to work a lot better than WD or any other oil type lube.  It does need to be cleanded and re-applied like WD though.I have never welded across the web of the beam, I have always been taught that is wrong no matter if the beam is heat treated or not.  I weld to the bottom and top of the flange only.  Anyone have any info on that?  Nice work all the same.TB 302 EFIESAB Migmaster 275MM 211 w/Spoolmate 100Hypertherm PlasmaMetal Master, Victor, and Smith TorchesUnihydro 45Wells BandsawArcair K2000Weldcraft Tig rigMiller 12VSLincoln PT 225No one can say I'm brand biased.
Reply:Originally Posted by Hank33I have found anti-seize to work a lot better than WD or any other oil type lube.  It does need to be cleanded and re-applied like WD though.I have never welded across the web of the beam, I have always been taught that is wrong no matter if the beam is heat treated or not.  I weld to the bottom and top of the flange only.  Anyone have any info on that?
Reply:Originally Posted by Stick-man...The union prevents me from hiring drivers anymore...
Reply:Originally Posted by Black WolfPoint 1 - Untrue when discussing Class 8 Trailer Frames,  as they are usually manufactured  from QT-100 Steel, it is more involved that just welding normal Mild Steel, and LEGALLY should probably only be done by qualified tradespersons.Point 2 - Torch cut holes in pretty much ANYTHING instead of drillling etc is pretty much the sign of an unskilled HACK ARTIST, and in no way belongs on a Class 8 truck, but we have all done what we have had to in the 11th hour to get the job done.  The issue is not with the use of heat to do the cutting, it is more WHERE the heat is applied, and the following HAZ (Heat Affected Zone) that may eventually lead to a catastrophic failure.  The components themselves for a Class 8 Trailer are cut using a variety of methods which include CNC Torch, Plasma, Hydo, and Lazer Cutting to name a few - All are acceptable.I would suggest though that if you have the option, a Mag Drill with an Annular Cutter is one of the BEST choices for making holes in frames - That said, it is up to YOU to make sure that WHERE you are punching the holes will not weaken the frame, or make it un-usable.Unless you are trained to do so, and KNOW what you are doing, the advice "Never Weld to a Frame Rail or Drill a Flange" are words to live by... I applaud your caution.I do not know the manufacturer of the trailer, but I would still wager a guess that the rails are QT-100 and special precautions probably should have been taken.  The re-pad probably should have been QT-100 as well.The reinforcing plate you mention above the suspension (IF OEM) was computer designed using Finite Element Analysis, and it was put in place by the manufacturer to address the stresses shown when running the FEA software.When you deck off a trailer while "Loaded" the weight ultimately rests on the suspension, and the dolly legs regardless of you having a full frame dump box, a 1/4 frame dump, a Side-Dump, or any other configuration.... The net result to be concerned about it the forces acting upon the dolly legs trying to TEAR THEM off of the side of the trailer.  The further the legs mount away from the frame webbing, the larger to Moment Arm, or Lever the Dolly Legs have to rip the re-pad from the frame.Overall, your welds DO look very Neat, and very Nice - High Marks for that, but I will give you a couple of points to ponder in the future:Consider matching the patch panel material to the frame material - Again, I am GUESSING that it would be QT-100.Consider Pre-Heating as is common when working with QT-100Consider using FCAW such as Hobart Fabco 100 in 0.045" and a Quality C02/Argon Mix as recommended by the manufacturer.Consider using Stich welds on the verticals as you have introduced Stess Risers into the Rails, and it will have an effect over time.Consider next time using a Thicker, and FORMED C-channel (Stronger) that is drilled to accept a Holland MKV ( For Example) Crank Down dolly leg, and BOLT your Telescoping leg to it... Then in future, replacement is a breeze, OR if you wish to upgrade to Crank Down legs, you are already 1/2 way there.I am NOT hacking on what you did, just giving you something to think about....Speaking of trucking - I preferred (same as you) to never have to deck off a loaded trailer, but when I DID have to, I made it a practice to stuff a 3" x 12" Rough Cut plank (or SOMETHING) under the legs so hopefully it was still standing when I got back to the trailer.  LOL.I haven't seen too many Rigid-Mount Telescoping legs on trailers "Up Here" as most of the Manufacturers make the legs "Swing Up" as well for Ground Clearance, and I prefer to have the option to do either, or both.  I Hated Cranking legs at -50°F or so, cause the grease is STIFF, but that is another matter.Have a Good Night.
Reply:[QUOTE=Black Wolf;425078]The reinforcing plate you mention above the suspension (IF OEM) was computer designed using Finite Element Analysis, and it was put in place by the manufacturer to address the stresses shown when running the FEA software.This trailer frame is estimated to be 30 years old or so. Did they have that back then?Consider using FCAW such as Hobart Fabco 100 in 0.045" and a Quality C02/Argon Mix as recommended by the manufacturer.I want to start working with FC just haven't had the money to buy another gun. I talked to Ivan from Hobart/McKay and he recommended Hobart XLR8 in 1/16" for the various projects I described. Also, why do you prefer this over mig?Consider using Stich welds on the verticals as you have introduced Stess Risers into the Rails, and it will have an effect over time.Point taken, and educated for the future. I was just duplicating what I have seen done.Consider next time using a Thicker, and FORMED C-channel (Stronger) that is drilled to accept a Holland MKV ( For Example) Crank Down dolly leg, and BOLT your Telescoping leg to it... Then in future, replacement is a breeze, OR if you wish to upgrade to Crank Down legs, you are already 1/2 way there.Would love to put on crank downs. I only worked 40 hrs in the month of July. Local 150 Operators were on strike.I am NOT hacking on what you did, just giving you something to think about....I do appreciate the input.I haven't seen too many Rigid-Mount Telescoping legs on trailers "Up Here" as most of the Manufacturers make the legs "Swing Up" as well for Ground ClearanceI have never seen these."Where's Stick man????????" - 7A749"SHHHHHH!! I sent him over to snag that MIC-4 while tbone wasn't looking!" - duaneb55"I have bought a few of Tbone's things unlike Stick-Man who helps himself" - TozziWelding"Stick-man"
Reply:[QUOTE=Black Wolf;425083]After re-reading the thread, I thought of something else...Now I am not sure if your binding issue is due to rusting and a build up of road grime between the tubes, or if your inner tube has filled with water and swelled when the water froze but I have a couple of ideas to make those legs work a little easier since you are the only driver, and these tips will directly benefit YOU.The tube actually bent just enough to bind it up.If the inner tube looks good, drill some drain holes at the bottom where the tube meets the foot pad, so that any water entering the lower tube throught the pin holes can drain. I was in a hurry. I only welded the sand shoe on in front and back. I planned on making a drain/cleanout hole at the bottom of the inner tube."Where's Stick man????????" - 7A749"SHHHHHH!! I sent him over to snag that MIC-4 while tbone wasn't looking!" - duaneb55"I have bought a few of Tbone's things unlike Stick-Man who helps himself" - TozziWelding"Stick-man"
Reply:[QUOTE=Hank33;425086]I have found anti-seize to work a lot better than WD or any other oil type lube.  It does need to be cleanded and re-applied like WD though.Anit-seize would collect too much dirt. WD is probably the best."Where's Stick man????????" - 7A749"SHHHHHH!! I sent him over to snag that MIC-4 while tbone wasn't looking!" - duaneb55"I have bought a few of Tbone's things unlike Stick-Man who helps himself" - TozziWelding"Stick-man"
Reply:[QUOTE=Mondo;425125]Nice repair!  But whats the comment about the union prevents you from hiring drivers? Union shop, teamsters only?-MondoYep, teamsters only. And at a cost of $50.00 and hour just to the driver and union. Then consider that I have been in for eight years and never once carded. (I had to join because of the health ins.) The only work going on right now is stimulus and requires minorities. I know the majority are not in the union. And they have cut the rates down to $73.00/hr on one major expressway job. In IL, the unions don't do crap except collect their extorsion money from the non minorities."Where's Stick man????????" - 7A749"SHHHHHH!! I sent him over to snag that MIC-4 while tbone wasn't looking!" - duaneb55"I have bought a few of Tbone's things unlike Stick-Man who helps himself" - TozziWelding"Stick-man"
Reply:Consider using FCAW such as Hobart Fabco 100 in 0.045" and a Quality C02/Argon Mix as recommended by the manufacturer.I want to start working with FC just haven't had the money to buy another gun. I talked to Ivan from Hobart/McKay and he recommended Hobart XLR8 in 1/16" for the various projects I described. Also, why do you prefer this over mig?Sorry Boss, I cannot tell you when the FEA software was introduced, nor if it was applied to a trailer that is potentially 30 years old - Maybe just take that in the spirit that it was intended (something to think about) and keep it in mind for the future.As to WHY I mentioned the FCAW wire?  That is fairly simple - You used ER70S-6 which has a Tensile Strength of around 70,000 PSI in the "As Welded" condition which is just fine for Mild Steel because it meets, and exceeds the Tensile Strength of the Parent Metal, BUT when you are playing with QT-100, it is Quenched and Tempered, and has a Tensile Strength of over 100,000 PSI which is WHY it is used for trailer frames and the like - Manufacturers has build in the Strength they need, by using thinner components to keep the weight down.  Going back to the 100,000 PSI Tensile Strength, by using the ER70S-6 GMAW wire, you have mis-matched your Filler Metal to your Parent Metal and you will have a weld deposit with substantially WEAKER properties to the Parent Metal which is generally NOT a good practice.Again, we have all at one time or another done what we have had to do, with what we have on hand - I am NOT hacking on what you did, just offering up some information for you to think about.I have ran ER70S-6 on Trailer Frames, and I am sure Neil (Wello) has as well - The point it to understand what you are doing in regards to the Tensile Strengh, and knowing when to use it, and when to reach for the "Good Stuff" so that the project is done correctly, and safely.The Swing up legs I mentioned are very similiar to what you have, just imagine a piece of pipe coming out from the re-pad you welded on, that is capped on the end with flat bar that is formed to go back to the trailer frame above the pipe, and essentially make a "Double Shear" mount to help prevent deflection, and direct the forces trying to twist the pipe off of the re-pad back into the frame...Then take imagine the top end of your existing telescoping leg, and weld on a piece of pipe that is larger than the one on the trailer, and just slips overtop (exactly the same as your telescoping leg) The pipe on the telescoping leg is drilled for a grease fitting.The support leg towards the rear is then mounted with a Double Shear design to a bracket on the telescoping leg, allowing it to swivel, and has a piece of pipe mounted at the top for a removable pin.The rear mount on the frame for the support leg is an upside down "saddle" that is a deep Formed C-channel.You want to use the legs, you pull the pin at the rear saddle,holding the leg in Transport Position, swing the telescoping leg vertical, swing the support leg up so that the pipe on the free end lines up with the pin holes in the rear saddle, and re-install the pin. After hooking up, pull the pin holding the rear of the support leg, and allow it  to drop against the telescoping leg, swing BOTH legs up (as a unit) until both are above the pin holes in the rear saddle, re-install pin to have legs in Transport Position.Pictures are worth 1000 words, and I will see if I can find one sometime this week - I have a LOT of pictures of the trucks I drove, and the trucks I built, but I never really paid much attention to dolly legs on trailers - Sorry.Gotta run - Heading to work.Later,Jason
Reply:[quote=Stick-man;425148] Originally Posted by Hank33I have found anti-seize to work a lot better than WD or any other oil type lube.  It does need to be cleanded and re-applied like WD though.Anit-seize would collect too much dirt. WD is probably the best.
Reply:I have even found anti seize in spray can form.   works just as well as the pain on kind.Vantage 500's LN-25's, VI-400's, cobramatics, Miller migs, synch 350 LX, Powcon inverters, XMT's, 250 Ton Acurrpress 12' brake, 1/4" 10' Atlantic shear,Koikie plasma table W/ esab plasmas. marvel & hyd-mech saws, pirrana & metal muncher punches.
Reply:Our company has been welding brackets on our flat decks to bolt up the landing gears in (sort of ) this way for over 20 years, with no problems. We weld a c shaped bracket onto the web, similar to yours but further out from the web and with holes to bolt the landing gears on. The only difference I can see in the welding is that we have no plate behind the bracket. A couple of 3/16" or 1/4" stiffeners are added on the other side of the web. Not sure what type of metal we use though, but I am sure our overpaid engineers know enough to keep things upright,lol. Nice welding.Last edited by yammyman; 10-02-2010 at 02:23 AM.
Reply:Originally Posted by yammymanOur company has been welding brackets on our flat decks to bolt up the landing gears in (sort of ) this way for over 20 years, with no problems. We weld a c shaped bracket onto the web, similar to yours but further out from the web and with holes to bolt the landing gears on. The only difference I can see in the welding is that we have no plate behind the bracket. A couple of 3/16" or 1/4" stiffeners are added on the other side of the web. Not sure what type of metal we use though, but I am sure our overpaid engineers know enough to keep things upright,lol. Nice welding.
Reply:Originally Posted by Stick-manI put the plate there for future. In case ever have to do this again, I wont be heating the frame.
Reply:[QUOTE=Black Wolf;425151As to WHY I mentioned the FCAW wire?  That is fairly simple - You used ER70S-6 which has a Tensile Strength of around 70,000 PSI in the "As Welded" condition which is just fine for Mild Steel because it meets, and exceeds the Tensile Strength of the Parent Metal, BUT when you are playing with QT-100, it is Quenched and Tempered, and has a Tensile Strength of over 100,000 PSI which is WHY it is used for trailer frames and the like - Manufacturers has build in the Strength they need, by using thinner components to keep the weight down.  Going back to the 100,000 PSI Tensile Strength, by using the ER70S-6 GMAW wire, you have mis-matched your Filler Metal to your Parent Metal and you will have a weld deposit with substantially WEAKER properties to the Parent Metal which is generally NOT a good practice.Again, we have all at one time or another done what we have had to do, with what we have on hand - I am NOT hacking on what you did, just offering up some information for you to think about.I have ran ER70S-6 on Trailer Frames, and I am sure Neil (Wello) has as well - The point it to understand what you are doing in regards to the Tensile Strengh, and knowing when to use it, and when to reach for the "Good Stuff" so that the project is done correctly, and safely.if  you were in the position of having to use 70k wire on 100k steel, would excessive reinforcement as  it is called be appropriate in order to  increase the 70k cross section to provide enough metal to match the adjacent parent metal?[quote=weldbead;426051][QUOTE=Black Wolf;425151As to WHY I mentioned the FCAW wire?  That is fairly simple - You used ER70S-6 which has a Tensile Strength of around 70,000 PSI in the "As Welded" condition which is just fine for Mild Steel because it meets, and exceeds the Tensile Strength of the Parent Metal, BUT when you are playing with QT-100, it is Quenched and Tempered, and has a Tensile Strength of over 100,000 PSI which is WHY it is used for trailer frames and the like - Manufacturers has build in the Strength they need, by using thinner components to keep the weight down.  Going back to the 100,000 PSI Tensile Strength, by using the ER70S-6 GMAW wire, you have mis-matched your Filler Metal to your Parent Metal and you will have a weld deposit with substantially WEAKER properties to the Parent Metal which is generally NOT a good practice.Again, we have all at one time or another done what we have had to do, with what we have on hand - I am NOT hacking on what you did, just offering up some information for you to think about.I have ran ER70S-6 on Trailer Frames, and I am sure Neil (Wello) has as well - The point it to understand what you are doing in regards to the Tensile Strengh, and knowing when to use it, and when to reach for the "Good Stuff" so that the project is done correctly, and safely.if  you were in the position of having to use 70k wire on 100k steel, would excessive reinforcement as  it is called be appropriate in order to  increase the 70k cross section to provide enough metal to match the adjacent parent metal?[/quote]Hey, NO offence taken what so ever from any posters here. I appreciate the comments. I am by far an experienced welder. However, most anything I weld I have confidence in it. You guys have definately tought me alot (like the reason for using a higher tensile strength fluxcor wire). If I hadn't seen this type of repair done before, I would have asked first. Thanks to all for comments and compliments, and especially for not being rude with the corrections!"Where's Stick man????????" - 7A749"SHHHHHH!! I sent him over to snag that MIC-4 while tbone wasn't looking!" - duaneb55"I have bought a few of Tbone's things unlike Stick-Man who helps himself" - TozziWelding"Stick-man"