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I hope someone can help me out with this. So I got myself a trailer for my car and took out the front braces that were on the trailer before because they got in the way and were too high up. Anyways when I removed them it caused the fenders to move back and forward too much and it keeps breaking my supports. I'm hoping someone has an idea of maybe fixing this issue so that the fenders and braces are nice and sturdy when I'm driving the trailer around.
Reply:My friend you completely destroyed the structural strength of that trailer when you cut off the front rails. Those rails formed a truss that supported the trailer. It's no surprise at all you had this issue, and you should thank God that you didn't have a catostrophic failure and seriously injure some one. The frame is flexing as you go down the road and fatigue will destroy the rest at some point soon most likely. If you need a flat deck trailer, buy one designed for this purpose. Don't try to red neck enginneer one on the fly by chopping up something with a completely different design.The only way to make this work, is to completely scrap the frame on this trailer and build a new one. Take a look at the heavy channel under a standard flat bed, then look at the light angle iron yours is made of. Not even remotely close.Edit: looking at the picts again, your welds look like they had zero fusion as well. Poor welds and destroying the structural design is not the way to modify a trailer. Please step away from the welder before you kill some one with this project.Last edited by DSW; 07-13-2011 at 01:02 AM..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:Damn your right....Might have to end up selling it and getting a flat bed like I wanted.
Reply:Originally Posted by DSWMy friend you completely destroyed the structural strength of that trailer when you cut off the front rails. Those rails formed a truss that supported the trailer. It's no surprise at all you had this issue, and you should thank God that you didn't have a catostrophic failure and seriously injure some one. The frame is flexing as you go down the road and fatigue will destroy the rest at some point soon most likely. If you need a flat deck trailer, buy one designed for this purpose. Don't try to red neck enginneer one on the fly by chopping up something with a completely different design.The only way to make this work, is to completely scrap the frame on this trailer and build a new one. Take a look at the heavy channel under a standard flat bed, then look at the light angle iron yours is made of. Not even remotely close.Edit: looking at the picts again, your welds look like they had zero fusion as well. Poor welds and destroying the structural design is not the way to modify a trailer. Please step away from the welder before you kill some one with this project.
Reply:Eh, I'm not upset at his post. I'm upset at myself but you live and your learn.
Reply:Originally Posted by dave powelsonAmen!...to all of the above.This is one great example of 'WHY?' ---the guys here with real world experience, get their backs uP,when seeing stuff like this-on trailers, trailer hitches and vehicles.Complete lack of weld fusion--how many other welds are like that?....and the fender brace weld is across the supporting beam (the inverted angle)?? Big no-no. This warranted criticism uPsets the newbies to no end--now we're tagged as 'Huge AzzHoles', etc.??does that trailer have brakes??In any case it needs to be condemned and scrapped....or taken to Ed Mac for a quicky repair.
Reply:Originally Posted by duffman1278Damn your right....Might have to end up selling it and getting a flat bed like I wanted.
Reply:Their all correct but you can also have someone that can weld better put it back the way it was and go back to gettin by with that.Miller thunderbolt 250Decastar 135ERecovering tool-o-holic ESAB OAI have been interested or involved in Electrical, Fire Alarm, Auto, Marine, Welding, Electronics ETC to name a just a few. So YES you can own too many tools.
Reply:One option is
.Get some scrap and practice, practice until you can get good welds. When you are done have a professional weldor check it out BEFORE you decide to use it for any hauling.Hobart LX235Victor 250 Oxy-Acetylene Rig (welding and cutting)Bobcat 773F-350, 1999, 4x4, 16' 10K# trailerOutdoor Wood Burner - 10 cords/year
Reply:convert the trailer into scrap.. and use it for welding practice and projects!"oh no, honey, the trailer broke, I have to buy this wonderful Road King with the onboard winch and shiny chrome bits"win/win. and don't do that again!
Reply:Ever play bridge builder for your phone or computer? That will teach you a lot about truss style sections, even though it is a stupid stick frame game.
Reply:Originally Posted by dave powelsonIn any case it needs to be condemned and scrapped
Reply:Originally Posted by duffman1278I hope someone can help me out with this. So I got myself a trailer for my car and took out the front braces that were on the trailer before because they got in the way and were too high up. Anyways when I removed them it caused the fenders to move back and forward too much and it keeps breaking my supports. I'm hoping someone has an idea of maybe fixing this issue so that the fenders and braces are nice and sturdy when I'm driving the trailer around.
Reply:So I'm having a hard time selling my trailer however I took measurements and modeled the trailer than ran some FEA analysis. And I'd like to get your guy's opinions on my new setup to fix this. I am able to get someone to weld it at my brother in laws shop I just need to cut and provide all the materials.
Reply:Your FEA analysis shows colors but no stress numbers. Kind of useless as a model to be honest.And is this a fatigue analysis or one time stress value? What values did you put in and how did you get to them? FEA is a great tool but unless you know what you are doing my old time adage is "garbage in = garbage out"If you know how to use the program then you are clearly not the average joe, but asking questions like this makes me wonder whether or not you know what you are doing or had someone do this for you. I don't want to start a pissing contest, but over the internet this is the best I can come up withMechanical Engineer
Reply:The stress numbers are off to the side and yes I know how to use the program and ran a simple static analysis. The highest principle stress was 32ksi. And yes I have taken courses in machine design I'm a graduating senior mechanical engineering student.Last edited by duffman1278; 09-07-2011 at 11:36 PM.
Reply:Unless there are photos circulating of this trailer other than what is posted in the OP, I would need to see more photos before advising scrapping the whole trailer. Perhaps its the camera, but is there a bow over the length of the trailer? I would have someone visually inspect the remaining structure, have the support structure rebuilt, and then use it for it's original purpose intended (light duty hauling...no vehicles)Last edited by jbyrd; 09-08-2011 at 02:13 AM.Jay DavisAWS-CWIC-60 Specialty Welding ContractorLoving husband, and father of two boys (
Reply:Originally Posted by duffman1278And yes I have taken courses in machine design I'm a graduating senior mechanical engineering student.
Reply:Your front could probably use a couple of uprights. The diagonals are probably overkill, not that they are not a good idea. I've never seen a factory trailer using them. Most simply rely on the welded moment conections of the vertical uprights to stiffen the truss and transfer loads. My guess is that it simplifies construction and fabrication more than it's from a lack of the need for them.I don't have the data, but 32 kips sounds high for such a small trailer and for such small members. Especially on a trailer that shouldn't weigh any more than 7000 lbs to begin with total.No offence, but my 1st thought reading your last comment was much the same as Boost's. You are a senior about to graduate with an engineering degree, and it never occured to you that you were cutting up a truss?.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:Originally Posted by BoostinjdmAnd you still cut the rail on the trailer? That's what edumacation will get ya I guess....I don't see any axles, springs, or shackles in your analysis. That makes a difference.
Reply:No need to reinvent the wheelEd 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:I wouldn't say he's reiventing the wheel. He's using the same system most "trusses" use. Verticles, and diagnals. It's a much more ridgid structure than simply using the verticles. However, in trailers, especially one built the way his is, there is such a thing as to ridgid. Something has to give, otherwise it will cause something to break. In the OP what gave was the very poor weld.in the post showing the common trailer, there is tortional, longitudinal, and latitudinal give in the structure of the trailer.There are no problems. There are only solutions. It's your duty to determine the right one.Hobart Handler 210Airco 225 Amp MSM Stinger
Reply:He is Reinventing the wheel- why change what was on the original trailer that he cut off and run an FEA analysis?Just put the Uprights back on without the Diagonal braces like it was originally built.as Boostinjdm stated"Repaired/rebuilt to original condition by someone that knows what they are doing would be sufficient"Not sure if you read the Op's 1st post and that he cut apart the Structure of the Trailer to haul a car and soon learned that was not a good ideer. He is not trying to rebuild the trailer to haul a car- he is only trying to make it useable again for its purposes, sell it and purchase a proper trailer for his needs.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:One advantage of trusses is to minimize material size. More lineal material in many cases but smaller members none the less. I doubt there's much advantage to going with a full blown truss design here. Especially when you may need substantial side members from time to time to tie off and what not. Plus the strength in an individual member is needed in different places at different times. I think for the utility trailers plain ole conventional risers and top rail probably work better all the way around. From a build perspective, who in the heck is going to volunteer to put all those angled cuts, fit-ups and welds into a job? Unless you simply enjoy doing things in new and different ways, go conventional."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:send it to ed mack for repairs, everyone agree? or anyone agree? |
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发表于 2021-8-31 23:34:02