Joining tent poles at right angles

Hi all. Been a while since I posted here, got myself into kayak fishing and having a ball.

Our camper trailer has numerous tent poles holding the main folding section up - they are joined at right angles to shape where the top of the canvas meets the side, or joins with it. At present they are welded. I accidentally flexed one too much the other day and heard a cracking noise when putting the camper down. Upon opening it today I saw one of the welds has cracked.

This seems like an inferior method of joining poles as there is no allowance for movement of any kind. If they went during a trip, in the absence of any welding equipment, the tent would virtually be useless.

I know some campers use shaped poles, but I can't go to these now due to the shape of the sides of the canvas. I'm thinking a much better way of joining the end of one pole to another on a right angle would be to use a right angled nylon sleeve, but I dont' know if they exist. I could carry spares and it would allow for some flex when erecting/pulling down.

Does anyone know if they do exist, and where to get them, or have any other brilliant ideas for achieving what I want???

Thanks all