Thread: a question re capacity of casters

I reckon that would be ok.
The weight should be equal on each leg.
(it could be heavier when wet but I think you have enough margin)

Hi Mattocks,

Yes you can multiple the rated weight by the number of castors provided the weight is fairly evenly distributed.

You can always mix in in some styrofoam beads with the soil to reduce the weight.

Thanks for the information everyone.
The forum is such a great resource and the knowledge of people on it is a great thing.

thanks again

Frank

One thing to consider is that the stated rating is generally under static conditions. As soon as you move the box, additional loading is exerted on the wheels. After having had some disappointing experiences, I now try and source castors that are rated at double the load weight.

Also be aware that with heavy loads (like your planter boxes with moist soil, polyurethane and rubber wheels can compress and cause flat spots if not moved for extended periods of time.

Kind regards,
Lance

That’s a good point Lance.
I was definitely looking at metal casters, mainly from an aesthetic point.
Makes better sense now

thanks again
Frank

If you want quality castors then I recommend these guys:
Home - Richmond Wheel & Castor Co
Very helpful and a good range including locally made product.
Castors - Richmond Wheel & Castor Co
They have a range of low profile castors with good load carrying that I have use which helps keep the total height down (and I think they look better).
Low Profile Castors - Richmond Wheel & Castor Co
No affiliation other than a buyer.

Good Morning Frank

A quick google says that the density of wet soil may exceed 2,000 kgs/m3. So an eighth of a cube could be over 250 kgs.

I thnk Lance has given you sound advice.


Cheers

Graeme

I have run into a similar issue with a tool box. A friend who is much smarter than I suggested to double the capacity.

For a 400 Kg total weight he suggested 200 Kg each casters.

One eighth of a cubic metre of water is 125kg, and soil is heavier, though some potting mixes are lighter than water and will float on water, so a fill of damp soil will be heavier than 125kg. Also because of the size of the unit, unless you know to the contrary, random users may well plant something that grows to 50-100kg in the box. Also I don't see a mention of the weight of the container itself, and any waterproof insert that may go inside it to stop soil moisture leaching through and spoiling the finish. Also unless they are to be used in an area with a mirror smooth surface, you need castors with a fairly big wheel to roll smoothly over any unevenness in the surface, or not get stopped by a small pebble. Supermarket trolleys with castors in the 150-170mm diameter range can't roll over a 1/4 minus pebble on the floor. A 1/4 minus pebble is one that can past through a rock screen with 1/4inch (6mm) openings at the crushing plant, so is fairly small.

Just a few things to take into consideration.

Just a thought outside the box.

Have you considered adding a largish plate of timber to the base to the same level as the legs and then add a castor in the middle to help spread the weight. The plate does not necessarily need to double thickness the base. My thinking comes from office chairs which used to have 4 legs but any of quality, today, all appear to have 5 legs.

Just a thought.

Bob,
Actually that is a brilliant suggestion.