Rolson Folding Trolley Wheel Stabiliser

This is a rather “niche” project, but many years ago I bought a Rolson folding trolley which is great for carting bags of compost from the car to the other end of the garden.

It has always bugged me that sometimes the wheels try to collapse inwards and the trolley wobbles and threatens to dump its load. It shouldn't really happen as the weight on the carrying flap is supposed to hold the wheels in position via the folding gear. Unfortunately that doesn't work very well and the force of the load directly over the wheels overcomes the force needed to keep them straight. I think they would tend to straighten if the loaded trolley is pushed forwards, but that's only possible on a very smooth surface, certainly not gravel or grass, and pulling the trolley allows the wheels to castor inwards and then it all goes wrong :o)

Here's the folded trolley, so if you have the same design then you could fix it the same way…

Rolson have redesigned it with a pushbutton mid-frame instead of the locking central riser - maybe the new design locks the wheels properly, I don't know, but if it doesn't then you may still be able to fix it using this technique if the wheel mounts have the same cutouts, though you might need a different length of dowel if your wheel separation is different from mine, but that's an easy alteration.

To lock the wheels apart and prevent them coming together in use, you need a couple of dented inserts to glue into the wheel mount mouldings…

A bit of epoxy on the back of the insert and they're fixed in.

Then you need a rod to click into the dents in the inserts. I could have printed a rod, but I normally have 15mm diameter hardwood dowel in stock so I used that. It doesn't really matter what it is, it just needs rounded ends to locate in the printed hollows. 

This particular trolley needs a 314mm rod, making sure not to remove any length from the tips when rounding off around them. Then you locate one end in a hollow, and use the flat printed area on the insert at the other end to guide the rod into position, it should be pretty tight, but it will come out again ok when it's time to fold up.

This is the position the unaltered wheels take at rest after unfolding…

This is what happens under load… the wheels start to toe-in…

… in that position they're not locked at all and the weight of the load will be straining the folding mechanism as well as being horribly unstable.

This is what it looks like with the rod in position…

I put the rod dents as close to the wheel axles as I could, to maximise the effective leverage. It's rock solid now.

The last job was to make a clip to store the rod in between uses…

Yup, job done! Would store flatter if I'd made the clip to fit on a side-bar instead. Shoot me now :o) Or design one yourself, hehehe. Snag is that on my trolley the side-bars need to be clear of any obstructions as they have a slide mechanism on them, so it wasn't very convenient to have the clip there.

Hope this helps someone else to cart compost/sand/cement bags around wobble-free! You can pay a lot for a sack trolley, but these little things are great if you can just stop the wheels wobbling.