Hi has anyone put wheels on their build in order to be able to move it? I've nearly completed my NST which is 10" shorter and narrower (working on the assumed measurements of a 9' 10" tall box. Already (without the roof) it must weigh close to 500kg. All wheels I have bought so far, the most recent having a loadbearing weight of 95kg per wheel, have failed dramatically. Any ideas would be gratefullhy recieved! many thanks...

I haven't yet, but we have a set of wheels that used to be used for transporting pianos.

If it were me,  I'd look for those caged trolleys they use in shops and supermarkets for moving loads of boxes around [you often see them in the drinks aisle piled up with bottles of pop and harder booze!]

Those wheels would be REALLY sturdy.

If you can't do that, I'd put five wheels on the base, one in each corner and another in the centre to try and spread the load evenly.

According to the seller, these castors [Ebay item number  280262001611 ] bear 750kg per castor.  Should be more than enough for your Tardis.

You may want to look into retractable castors.
Bill Rudloff

I have 6 castors under my base each looks like an office-chair castor and is rated at about 100kg each I think but might have been up to 200?  ...And they've worked fantastically - build rolls around with (relative) ease but wheels are unseen and have held up well for some 4-5 years now??!

Castors are in each corner and the other two are spaced across the diagonal in one direction.  I figured it was better to overengineer than under

-glen

If I were to put casters on the bottom of my box (not going to happen with my build), there are a few things I'd look at:

1) Exactly how much does your box weigh? 
2) How much weight are the casters rated for?

It might be tempting to divide the box weight by the rating of the casters and buy that many casters, but I'm suggesting that this probably isn't enough.

Another weight issue to think about is occupants.  Will anyone stand in the box while it's sitting on casters?  More than one person?  Will people be excitedly moving into the box, possibly jumping up and down?  If you would take the box to a Dr. Who convention and let people play with it, this could occur - and it's a whole bunch of weight that you need to take into account.

Another issue is that the weight may not be evenly distributed (especially with people inside).  Also, when you move it, going over a surface that's not completely smooth might mean that the entire weight is resting on fewer casters at some points.  You'll have to compensate for that as well).

What I'm getting at is that if you want to put on casters, I'd suggest putting on more than you think are needed and/or buying casters with a higher rating (I don't seem to have trouble finding ones rated to 500lbs ~ 225kg).

I'd be tempted to put 8 or 9 rather than 4 or 5 casters, but then I like to over-build things.

Colin

Dear all, many thanks for your suggestions, it became all too painfully obvious that I had underestimated the weight of it!! Just as I got my paintbrushes out to do the primer coat, and shifted it into position so I could get behind it (it was close to my garden fence), one corner gave way so I spent the rest of the afternoon upending it to take my new, but now buckled wheels off! Still it looks fab and I hope to post some images soon once it's finished! Thanks one again for all you help, Gavvers

I have some standard heavy duty (non retracting) castors on mine (x4)

1. The box has been pulled out of a muddy hill by a van (the wheels sunk into the ground a few years ago and this was the only option to get it out)

2. Dragged across uneven gravel to the tune of some 500 yards during it's lifetime.

3. Had numerous adults in there at the same time (but we won't go into that one!)

The castors are absolutely fine, and are still going strong after nearly 5-years.

You should consider the thickness of your base though, as it is possible that the base itself may crack.

Bumping this old thread :-)

I'm currently having my old "This Planet Earth" GRP TARDIS refurbished and have decided to build a wooden frame for the base to sit on and am going to put it on castors.

Would these be suitable?
http://www.ebay.co.uk/itm/Set-of-Heavy-Duty-100mm-Rubber-Swivel-Castor-Wheels-Trolley-Caster-Brake-600KG-/291596046797?var=&hash=item43e47a91cd:m:m9k2cOsVEN0CyQRk9WjM1Eg

Or can anyone recommend any alternatives? Cheers