Is my trailer compromised?

[Joolz]

Should I be worried about this gap in the frame? Got the boat last year and have been doing some repairs to it. At some point some years ago someone welded a makeshift fender in place, welding it to the frame. This was a very heavy piece of 4mm thick metal bent to resemble a mud flap. Eventually the weld broke off and this ugly makeshift fender had to go. Upon removing it I noticed this gap in the frame, that's right above where the leaf spring attaches to, an already stressed area.

The trailer appears to be OK and it has lasted all this time (how much time has elapsed is anyone's guess) but should I be worried? The bulk of the weight of this outboard boat is at the rear, so it makes me wonder how much stress is placed onto the rear of the trailer, where this gap is. Of course, the boat sits on bunks and its weight is distributed throughout so perhaps this is a non issue. But does this scream "repair me before I break loose?"

 

[GA_Boater]

You answered yourself.

"repair me before I break loose?"

The spring mount is carrying a lot of weight and hitting a bump hard could drive the mount through the frame.

Any rust blisters else where on the frame?

 

[Alumarine]

Also, the weight is not distributed throughout.
Most of the weight is towards the end of the bunk.

 

[Joolz]

Any rust blisters else where on the frame? [/I]

No other rust spots anywhere, trailer is otherwise in excellent condition. I suppose one could claim that since it has lasted this long that it should continue to do so. But isn't stress a cumulative thing? I mean, metal fatigue doesn't get better with time. So yeah, for my peace of mind I concur that this ought to be addressed.
It's always something, ain't it?

 

[hemi rt]

I would clean the paint off, check the top of the frame for straightness, if OK then weld a fishplate over the opening and repaint the area.

 

[GA_Boater]

While you have an opening, look inside, Trailers with tube frames rust from the inside out.

 

[ahicks]

In the name of preventative maintenance (PM) another vote for a fish plate/reinforcement.

 

[Joolz]

Welding a fish plate to the frame is what I was thinking too. Figure that a 24" to 30" plate ought to be enough. 1/8" thick and spot welded every 2". What do you folks think? Overkill or not enough?

Hoping to go buy it later today so I can address this over the weekend (likely not going out Sunday anymore as weather isn't looking promising).

 

[SkaterRace]

That should be fine for what you have. Ideally I'd look at figuring out how to reenforce the top too as I am sure that has some 'sag' in it by now. If any sag I'd look at doing both sides and maybe the top too. Then again I am the one who build a transom that withstood a 30mph crash without any noticeable damage (still replaced again) so I tend to go overkill.

 

[Joolz]

K, so I may have a bigger problem in my hands than I realized.
Just now I removed the fender and took a straight edge to the frame. It has sagged a bit over 3/8". On the other side, the frame has also sagged but by about half that amount. Suppose that it is common for steel to flex a bit with all that weight back there?
So yeah, whoever welded the fender to the frame really did quite the job on this trailer. This is now something I need to address and soon. But how? Should I first unload the trailer prior to welding the fish plate to the frame? Or do I just jack up the boat in order to relieve some of the weight? The first option isn't really a feasible one. Welding a 30" long, 3" wide plate to a curved surface wouldn't be easy either.

Really could use some advice here.

 

[Lowlysubaruguy]

If you decide to weld a reinforced plate here look into recommended weld spacing do not weld a solid stretch a reinforced plate like this is stronger and less likely to break if welded in spots most likely 1 to 2” welds with 1” gaps between them. be sure to clean and prime the areas with a weld through primer on all pieces and prime the entire area with an etching primer before painting the repaired area.

 

[Joolz]

Great, thanks for the tip. It may be a bit of a struggle to accomplish this neatly with a 70A welder (and my inexperience) but as long as it holds, I'm not too concerned with how it looks. And I do have the paint already, along with a grinder to remove some rough edges.

Would you concur that a 3/16" plate to be thick enough? Quarter inch seems like overkill. And do you think doing just the one side to be enough or should I weld plates to both sides? How long should the plates be?
Again, the more details I'm fed the better the chance this gets done properly.

 

[Lowlysubaruguy]

Hard to say what the best approach is if there is more damage on the inside that you cant see you may need to splice a longer area. Have you made good welds in 3/16” plate steel with your welder. You could rent a bigger one? I’d probably use 3/16” plate weld one piece on each side fitting them in a manner that you can lead the next plate into the edge of the previous one. Personally I might cut that spring bracket off and use a piece of angle iron one on top and one on bottom and then weld the bracket back on. If you drilled a few 5/8” or larger holes in the middle sections of the reinforcement you can split weld them to the trailers frame to gain some strength from more than just the outer edges if that makes sense. I doubt you’ll need 1/4” plate if you wrap all the way around and have spot welds in the middle as well.

 

[Lowlysubaruguy]

Sorry thats spot weld not split weld spot welds help distribute forces that will be present in this area.

 

[Joolz]

Are you referring to using 2 L shaped plates, basically encasing the frame? I can see why that'd make it super strong, especially if I was to make the length 4 or 5' long. I get what you mean about making holes and spot welding it to the side of the frame. Would you drill holes through both objects or just the plates? I wouldn't trust myself to weld the spring bracket back on but that is a very good idea, seeing how that area is compromised but can always find someone that would.

Today I took a closer look at the frame. Tried to lift the boat off the trailer a bit in order to check if the frame would straighten itself out. Jacking up the boat didn't go very well but the bit that I managed to lift was enough to move the end of the frame up some 3mm. While doing this I also noticed that the frame isn't straight anymore: not only it is sagging a bit, but it's also turning outward a bit. The same is happening with the other frame on the other side of the trailer. Since the boat is on the trailer perhaps it is the weight of the boat that's causing this bit of twisting. Only way to be sure is by relieving the trailer from the boat's weight. So the plan now is to head to the lake in order to unload the boat and carefully check the framing. If there's still some sagging and a bit of curvature to the frame then I may have to consider some stronger measures. Fixing this may be beyond my capability but we'll see.

I simply cannot believe that someone was so reckless in damaging a perfectly fine trailer in an attempt to weld a fender straight to the frame. Even I know better than to do this. Whoever did this could have first welded a plate to the frame. Apparently not everyone with a welding machine isn't a welder (or have much common sense).

And yes, I managed to build a pair of trailer guides using 1/8" tubing that I'm pretty proud of, as well as a some parts for this trailer that turned out very decent. But I'm still learning and enjoying it. Since I'm not expected to run a bead through the length of the plate for this job (as you pointed out, 1 inch welds are best) then I'm pretty sure I could accomplish this, even if a couple of them don't turn out superb. I can always look at getting a better welding machine for the job. Been considering getting a better one anyhow. This kit was only $50 on sale so I nabbed in order to get my feet wet. Now that I realize that there's plenty that can be done with a welder I may just look for an excuse to upgrade. This job here may be just the excuse I need.

Please stay tuned. Could use your advice once I have the chance to unload the trailer and see what shape the trailer is in. Thanks.

 

[Joolz]

An update on this: found an easy fix - will let someone else do the welding for me :joyous:
Bought a L shaped 2"x3", 4 foot long and 3/16" thickness to go over the side and top of the frame. Experimented welding on a scrap piece of 3/16" with my stick welder and it didn't go well. Even better, this welder/mechanic lives in a town only 20 km from the lake. Meaning that once I unload it, I can be at his place in 20 min. Shouldn't take more than an hour to do the job, so wife and kids will hang around the boat having a picnic. Cost should be minimal, will update tomorrow once we get this done (weather permitting).

Once this step is over with will be looking at a better welder.

The wires for the tail light run inside the frame. Will this have to be removed prior to welding? Fear the heat will melt them. It's a long, curved way from the tongue (where I can access the wires) to the tail light. Is there a trick to removing/replacing the wires if indeed they need to be out during welding?

 

[MTboatguy]

Fish tape is the way I run wire inside the tube.

https://www.harborfreight.com/50-ft-fish-tape-38156.html

 

[jimmbo]

deleted.

 

[Joolz]

Thanks for the idea, I happened to have 20m of pretty stiff wire from the dollar store that worked great. Fed it through the back of the trailer, tying it to the front. When I get to the shop I'll just disconnect the lights wire and once all is done, will drag the stiff wire tied to the electrical wires back through the frame. Piece of cake.