NT 5x8 Tongue Crack Help

[Dan P]

Greetings,
I was at a gathering recently and a fellow member told me about a problem he had with his NT trailer. We went to my trailer so he could show me and sure enough, I had the same thing going on. Looks like my NT Trailer has a crack on both the left and right side where the tongue plate connects to the C-Channel (See pics). I was wanting to extend the tongue another 12 inches anyway, so now this gives me a good reason to not delay. Any recommendation on the best way to fix and extend?

Image1.jpg (24.5 KiB) Viewed 586 times

Image2.jpg (45.1 KiB) Viewed 586 times

[Hubert]

I don't have a good suggestion how to fix this, but I would recommend to take a look at this page about tongue strength https://web.archive.org/web/20160425130632/http://www.angib.pwp.blueyonder.co.uk/teardrop/tear84.htm. Is this the trailer you added brakes to? This will increase the load on the tongue, maybe that's why it started cracking. A longer tongue will also require stronger materials. If you know the weight of the trailer, the spreadsheet on the page I linked might give you a starting point as to what gauge material you need to use for the new tongue to avoid future cracks.

[Dan P]

Awesome. thank you for the info. Much appreciated. Yes, this is the trailer I added brakes to.

[TimC]

Thanks for posting this. I've got a NT 5x8 as a utility trailer and my son and brother both have NT teardrop chassis. If I find any similar cracks I'll report back.

Tim

[QueticoBill]

I think my signature has how I extended NT tongue. A piece of 2 x 2 x 1/4 back to middle cross member.

[tony.latham]

I think the fix–-after the crack is welded--is to install a piece of pipe as a spacer on the bolts that crank down on the channel (or tubing). The spacer needs to be a good fit inside with no slop.

But others who have had this issue might chime in with how they addressed it.

Tony

[TimC]

I think the fix–-after the crack is welded--is to install a piece of pipe as a spacer on the bolts that crank down on the channel (or tubing). The spacer needs to be a good fit inside with no slop.

But others who have had this issue might chime in with how they addressed it.

Tony

Someone please correct me if the design I have has changed...

Tony, I'm sure that that fix (a spacer) would help with new longer bolts, however, the three NT trailers I have assembled have individual bolts, washers and nuts on the top and bottom. They are not cranking down on the C channel.

The flat plate you see in the second photo is not bolted through the C channel to the bottom with three individual bolts. The three bolts you see in the second photo (the curb side of the tongue) are actually six individual bolts, three on top and three on the bottom. That is repeated on the other side of the plate on the road side. So twelve, yes twelve bolts on the flat plate tying the tongue assembly together.

I did something similar to Pat's design change when I added a longer tongue tube that goes from coupler straight back to the frame. That upgrade was to allow carrying 17' canoes which would have been awkward with the short supplied NT tongue.

[tony.latham]

however, the three NT trailers I have assembled have individual bolts, washers and nuts on the top and bottom. They are not cranking down on the C channel.

Gotcha. I think you caught me armchair quarterbacking from a distance.

Tony

[KCStudly]

Before welding make sure to find the end of the crack and drill an arresting hole. Then gouge out a vee notch weld prep along the length of the crack using a thin-ish grinding wheel and 4inch grinder, or tapered rotary file in a die grinder. Probably best to disassemble the items off the front of the tongue so they aren't fighting you and clamp well to move the uplifted portion back into position. After welding the gouged out crack and arresting hole, fit a closure plate to the front end of the 'C' and weld that in. The closure plate will tie the top and bottom legs of the 'C' together making it much more resistant to allowing the upper flange to curl up (which is what caused the problem in the first place). Unfortunately, you can't box the channel because you need to be able to access the fasteners, but adding the end cap closure plate should be plenty enough. Use material of similar thickness to the 'C'.

[Dan P]

I think my signature has how I extended NT tongue. A piece of 2 x 2 x 1/4 back to middle cross member.

This is perfect! Thank you so much for replying; it is exactly what I needed. I will be picking up a 2x2 piece tomorrow! Thanks again!

[Dan P]

Before welding make sure to find the end of the crack and drill an arresting hole. Then gouge out a vee notch weld prep along the length of the crack using a thin-ish grinding wheel and 4inch grinder, or tapered rotary file in a die grinder. Probably best to disassemble the items off the front of the tongue so they aren't fighting you and clamp well to move the uplifted portion back into position. After welding the gouged out crack and arresting hole, fit a closure plate to the front end of the 'C' and weld that in. The closure plate will tie the top and bottom legs of the 'C' together making it much more resistant to allowing the upper flange to curl up (which is what caused the problem in the first place). Unfortunately, you can't box the channel because you need to be able to access the fasteners, but adding the end cap closure plate should be plenty enough. Use material of similar thickness to the 'C'.

Thanks for the tips. Unfortunately I dont have a welder, but will be a bit more informed when I find someone to do itfor me.

[QueticoBill]

My adding the 2x2 and inverting the NT bent plate intended for coupler does lower coupler 2". Works fine on my tow vehicle. Also, just bolts and drilling, no welding required.

[pchast]

Of course the crack is likely the result of stress.

I'm not a materials engineer But it seems like:

That stress might be eliminated by any method of boxing the c channel
where its bolted. Then there would be no lever to bend.

[philpom]

I'm thinking that @Tony hit it with his spacer comment. After repairing and/or as a preemptive fix I suspect that buying longer bolts and placing a nice large diameter tight fitting spacer in there would give a similar effect to boxing it off. By directly associating the lower section of the C with the upper section it'll shore it up and end any flex.

[TheOtherSean]

I had a very similar problem develop with the tongue of my build atop a NT 5x8 trailer while towing it back from Montana last year. As a temporary fix I replaced the individual bolts at the end with bolts that went all the way through. This year I reinforced with heavy duty angle iron inside the C channel, bolted into the side and top of the channel. At the front, the bolts through the top go through the coupler plate, channel, and angle iron. No problems with it during this year's trip.