Strengthening 76 Boler frame

[Duke]

I'm hoping to go on a long trip with my 76 Boler from BC to Newfoundland and back in the summer of 2023. There are no obvious cracks or twists in the frame but I wonder if I should have strengthening plates or bars added to the parts of the frame that can have problems, Just in case. Don't want to be halfway across the country with a broken frame. What do you think?

[redbarron55]

Take a good look on the insides of the bends in the frame towards the front and also on the frame and reinforcements on either side of the door where the frame is cut to allow for a level floor at the door.
The frame rails sideways are not as stiff as the vertical frame and this causes flexing and cracks. The flexing of the frame at the door aggravates the cracking at the bends as well.
Where the frames are bent and the bending actually has failed the tubes and added stress and weakens the structure.

[Duke]

Good advice. I will check all you suggested. Thanks

[redbarron55]

The reason the frame is weak is thin material on the early frames like the early Scamps and the pre failed bends on both sides.
If you look at the frame rail tubes you will see that they are already buckled and the inside is forced inward and the top and bottom have slight bulges.
In my opinion this area should be (or should have been) plated over these areas as most of the strength of the tubs has already been lost.
A fish plate on the inside and outside, tapered on both ends to reduce the stress riser generated by the stiffer area and you should be good to go.
It is likely that there are already cracks if the trailer has been used hard over rough roads. My experience has been with Scamps, but the frame and basic trailer is really a copy of the Boler design.

[Duke]

Originally Posted by redbarron55

The reason the frame is weak is thin material on the early frames like the early Scamps and the pre failed bends on both sides.
If you look at the frame rail tubes you will see that they are already buckled and the inside is forced inward and the top and bottom have slight bulges.
In my opinion this area should be (or should have been) plated over these areas as most of the strength of the tubs has already been lost.
A fish plate on the inside and outside, tapered on both ends to reduce the stress riser generated by the stiffer area and you should be good to go.
It is likely that there are already cracks if the trailer has been used hard over rough roads. My experience has been with Scamps, but the frame and basic trailer is really a copy of the Boler design.

Thanks for this. I hadn't heard of a fish plate before and had to do some research.

[pault]

Fish plates are extra plates welded to a frame to reinforce joints and bends. Any place a steel frame is bent or welded is a potential weak point that can crack.
Depending on your skill level, it is a fairly easy repair to do. Because the frame on a Boler is thin, it may be a good idea to have a professional welder do the repairs.
Here are a couple of pictures of fish plates I put on the frame of a vintage trailer I recently rebuilt.

[Nancy F]

Originally Posted by Duke

I'm hoping to go on a long trip with my 76 Boler from BC to Newfoundland and back in the summer of 2023. There are no obvious cracks or twists in the frame but I wonder if I should have strengthening plates or bars added to the parts of the frame that can have problems, Just in case. Don't want to be halfway across the country with a broken frame. What do you think?

Wow, that is our plan too, to go from BC to Newfoundland and back next year, maybe we will see you on the road. Not sure how to post a pic of our rig, but you can't miss us. Atomic orange 1976 13' Boler with 1951 Chevy tow vehicle same colour.
Good luck with your mods and trip next year.

[Duke]

Originally Posted by Nancy F

Wow, that is our plan too, to go from BC to Newfoundland and back next year, maybe we will see you on the road. Not sure how to post a pic of our rig, but you can't miss us. Atomic orange 1976 13' Boler with 1951 Chevy tow vehicle same colour.
Good luck with your mods and trip next year.

Thanks and good luck with your trip. We don't have as stunning a colour for our Boler. Original yellowish colour. Hoping to leave in May and return in August. Happy New Year.