DIY Doctor UK DIY Forums

Hi - can anbody help please?
I am putting coving up in my daughters' bedroom, and despite carefully following (and double checking!)instructions from a reliable DIY suppliers website can't seem to get corners right.
There is always a gap at the corners. I am using paper covered polystyrene coving (lighter for us girls to put up!) 13cm across. The box is a standard 10cm one.
All the diagrams show the coving fitting neatly into the mitre box, but mine is proud of it. Am I getting the wrong angle because of this? Should I put a block into the mitre to ensure that the top edge (fits to wall) is at right angles to the mitre box base?

If you're coving block is too small for the coving then you will find it exceptionally difficult to cut the correct angles as the coving will never sit flat in the box.

I think the best advice would be to take the mitre block back (if it's still as new) and buy a bigger one, or buy a specific mitre cutting guide.

I recently fitted 100mm coving for the first time using an appropriately sized mitre block and other than wasting a foot or so cutting an external corner rather than an internal one everything went up like a dream.