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Thread: Trailer repair

  1. #1
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    Default Trailer repair

    I have a trailer that needs a new A frame, it's made of 50 x 50 x 2mm tube. A repair has been attempted in the past by welding up the cracks and welding 50 x 2mm angle iron to the outside and bottom faces(I haven't removed yet as I'm pretty sure the A frame will fall apart).

    I've cut the tray out. ATM I'm guessing it failed across the top of the tube first. The front of the trailer has been welded to the tube on all four sides, I assume it was made like that as you cant get to the ones in the picture without taking the tray out. I recall this being a bad idea. So with the replacement, weld all the way around or just the sides?

    Thanks
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  2. #2
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    Welding across the top of the A frame tube is a bad idea and is a location for stress fractures. The A frame at the front of the bed should be welded only on the sides using gussets to connect to the bed.

  3. #3
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    Sorry for my lack of drawing skills.
    Left, right or something else?(the top piece is 50 x 2mm angle or thicker if I cant get 2mm locally)

    The back welds seem to have held up ok. Should I put a gusset over that?

    One more thing, The angle iron that goes across the trailer under the tray has bowed down. In a perfect world that angle would be fitted the other way up right? (given its a one off I will likely just replace with tube)
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  4. #4
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    Quote Originally Posted by Stustoys View Post
    Sorry for my lack of drawing skills.
    Left, right or something else?(the top piece is 50 x 2mm angle or thicker if I cant get 2mm locally)

    The back welds seem to have held up ok. Should I put a gusset over that?

    One more thing, The angle iron that goes across the trailer under the tray has bowed down. In a perfect world that angle would be fitted the other way up right? (given its a one off I will likely just replace with tube)

    Either is fine just no weld across the top.
    The back weld is different as there is no flexing at that point, ideally all junctions should be gusseted.

    I see that it is a typical cheap trailer, in a good design the drawbar should continue and attach at the location of the front spring hanger for the axle but most trailer manufacturers dont use the extra material to do that.

  5. #5
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    Hey they got within 100mm.. so close. lol
    I can move it back no problem as long as welding the tray support RHS to the inside of the A frame is ok.

    Yeah its a cheap light duty trailer.(well I don't know it was cheap but I hope it was). I guess its been overloaded at some point in its life also, but that seems pretty normal life for a trailer.

  6. #6
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    Procrastination pays off again

    I've realised I want to change the A frame to a single drawbar, because it will increase the angle before I jack knife the quad from 47deg to 70deg.
    Then I thought it might be handy if I can remove the drawbar.
    Then it would be handy if it can tilt.
    Anyone seen such a thing?


    For an extra point I'm thinking of adding a hitch to the back of my other trailer so I can have my own little B double lol

  7. #7
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    Quote Originally Posted by Stustoys View Post
    Then I thought it might be handy if I can remove the drawbar. Then it would be handy if it can tilt. For an extra point I'm thinking of adding a hitch to the back of my other trailer so I can have my own little B double lol
    Hi Stu, for your removable drawbar, have a look at some of the smaller boat trailers.boat trailer.jpg
    Most have an "A" type frame that meets at the front, then joins onto a single pole drawbar, it is easy enough to make the single pole go back far enough, to the front of the trailer for example and then pivot. Where the "A" frame meets you'll need to fabricate an inverted "U", so that the drawbar goes in there when the trailer body is lowered. To remove the drawbar it is just a matter of removing the holding pin.
    To enable you to have a tipping trailer, all that needs to be done is to get a boat trailer winch, 3 sheave pulleys, and some metal to make a post for the sheaves, usually square tubing. Set your chassis up so that the top can pivot behind the springs, use some 12NB pipe and 15mm bolts for the pivots The sheave post will need 2 pulleys at the top and one at the bottom, it will need to be about 900mm high and also pivot at the bottom, this will be at the front of the trailer body. https://www.youtube.com/watch?v=5-tdfIVCmCM This one shows a winch being used as a direct lift, wouldn't like to try it loaded with dirt/firewood etc. but you'll get the idea.
    So that you can go "B" Double, you'll need a piece of 65X65X6 to go under the back of the trailer, (similar to most towbars), ideally this should be attached so that the pulling strain is shared over the whole trailer chassis, not just the rear X member, say a length of 50X50X3mm RHS attached underneath connected to the front of the trailer. As a minimum, you could go to the next cross member back. Quite often you'll see this arrangement on the back of camper trailers/caravans
    I'm suggesting this method, as you haven't stated what sort of load/weight you'll be pulling
    in this configuration.
    If you're replacing the floor at the same time, do your drawbar first, as if the floor is welded in prior, it MAY end up with a twist. DAMHIKT
    HTH
    Kryn
    To grow old is mandatory, growing up is optional.

  8. #8
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    Hi Stustoys

    A tilting trailer can be handy depending on what you want to do with it. If you're moving dirt etc, most of the tilt trailers I have seen, including the one I own, require you to shovel out most of the load because the tilt angle isn't high enough. Also, if you load the trailer too far forward, it can get pretty difficult (heavy) to get it to tilt. Of course, a tipping trailer is a lot more expense. The trailer I have that tilts, hinges at the axle (it's a single axle trailer) and it is handy to use the tilt as a ramp at times, but I get tired of having to unload it with a shovel and I often find that the back of the tilted trailer gets buried under the dirt, gravel etc and makes it hard to drive forward to get room to unload the rest. Not a good thing to scrape your metal tail gate hinges across your new pavers. If you just need a "ramp", make a couple that can store under the trailer and slide out when you want to use them.

    Folding, extending and removable draw bars/ trailer tongues are handy for long trailers, especially boat trailers, so that's not a bad idea, you just have to get the engineering right so that you don't end up with oncoming traffic wearing your trailer. Such a drawbar means that you don't have to have such a big shed to store the trailer in either. I modified another trailer that had A-Frame issues a few years ago by making a longer single drawbar that used the existing A-Frame a bracing and ended up with some extra clearance when making sharp turns like you have suggested. It also made the trailer easier to back, stopped it from fish-tailing and bouncing all over the road and just gave me a whole lot more confidence about the trailer behaving itself.

    That's just my 2 cents worth, but hopefully there's a couple of useful ideas.

    Simon

  9. #9
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    Thank you gentlemen.
    Quote Originally Posted by KBs PensNmore View Post
    I'm suggesting this method, as you haven't stated what sort of load/weight you'll be pulling
    in this configuration.
    The trailer will be used mostly for firewood and "left overs" going to the fire pile. So generally not a huge load or high speed but the hills can get steep. I'd like to say "it will never see the road again" but I can't guarantee that so don't want to do a half assed job of it(the B double side of things can be halfassed as obviously that will never see the road)

    I don't have to worry about damaging the drive so was thinking about pivoting on the axle, but given the Simons comments will have another think and do some more measuring. I did unload a couple of loads of mulch by unhitching the trailer so I get what you mean about angles. Don't want to add the weigh required to make a separate tipping tray as its going to spend some of its life behind a quad.

    One thought did cross my mind the pivot could be in the draw bar(subject to the hitch being able to handle the angle change). So I could build the removable drawbar side of things, have a working trailer and then see if I ever get around to adding a pivot, maybe even have two drawbars?

    Will check some angles when the rain stops.

  10. #10
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    Welding across the draw bar isn't recommended , apparently the main reason is for safety i.e in the event of an accident the trailer A frame triangle section will fold up or separate on impact. I've noticed the old school trailers are all welded across the drawbar, lol. I would patch the cracks and attach a new section of RHS directly underneath going min full length of drawbar or longer if possible and welding them together for strength.

  11. #11
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    Quote Originally Posted by Stustoys View Post
    One thought did cross my mind the pivot could be in the draw bar(subject to the hitch being able to handle the angle change). So I could build the removable drawbar side of things, have a working trailer and then see if I ever get around to adding a pivot, maybe even have two drawbars?
    Could you run a single straight drawbar to a pivot point on the axle, with a latch to hold the front of the trailer down? To dump, all you'd need to do is make sure you've loaded it a bit tail heavy, pop the latch and it should pivot on the axle. You could also then reverse a little to increase the dump angle.

    Something like this:
    gallery5_1_23.jpg

  12. #12
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    Quote Originally Posted by RustyArc View Post
    Could you run a single straight drawbar to a pivot point on the axle,
    If I didn't have springs maybe. I have had some ideas along those lines but I'm worried about putting much load at the center of the axle.
    Also, with the axle pivot setup its the over hang that limits tip angle, where the other pivot is has no effect on that angle(up to the point that there isn't enough draw length for "the other" side of the triangle) . Did some measuring today, with my trailer the tip angle is going to be limited to something like 27 degrees. If the pivot is at the front of the tray that will mean the hitch needs to be able to pivot little less than that, which it can just manage. Though I can raise the ball on the truck if needed.

    Have to have a think as to whether 27 degrees is worth it.

    To late to patch the trailer up, I cut it all of months back, even bought the steel to fix it, just haven't had the time/weather.

  13. #13
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    Some more thought on Rusty's idea.
    How about an A frame made of 25mm SHS that just hooks over the axle and runs under the drawbar, fixed(with some slop) to the towbar. It should be easy to fit and remove as needed and wont be under any load until the hitch is undone. Seems easy enough to try(well if the world hasn't run out of 25mm SHS lol)

  14. #14
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    I'm not sure exactly how your 25 SHS A-frame is meant to work?

    There's a terrible-looking trailer that I think has been abandoned where I work - I'm tempted to have a go at my idea.

    I think I'd go with the single drawbar, but maybe add two extra bits of SHS at 45 degrees and connect to the axle in 3 places, which should spread the load. I'm pretty sure I've seen a version of this that has spikes or something at the base of the tailgate to engage with the ground when tipped, so you can reverse further, lifting the tyres off the ground and increasing the tip angle.

    If you're interested in other tipping options, check out my slightly more involved conversion:
    https://metalworkforums.com/f184/t20...ler-conversion

  15. #15
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    The 25SHS A frame just stops the trailer going any where when tipped, with maybe limited forward/backward movement. As an added bonus it shouldn't be to hard to have it fit both trailers.

    I'm not seeing how your idea will work on a trailer with springs. Once you latch the front of the trailer to the draw bar that's going to mess with the springs.

    Thanks will have a read of your thread.

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