On 13/04/2021 19:52, alan_m wrote:
On 13/04/2021 18:01, wrote:

- The 900 base units have double doors but was hoping to not have the
vertical bar up the front.Â* Will the 18mm ply be ok without the support?

The vertical is usually there to form a "stop" for where two doors meet
in the middle.

Will the 18mm ply be ok without the support?

That very much depends on the weight of any item you are going to put on
the centre of the top.

Just support the 18mm ply on two scraps of wood at 900m centres. Place a
representative weight in the middle of the span and use a long spirit
level to check deflection. Don't forget if your doors are inside the
frame the bend/deflection of the top cannot be hidden by these doors.
Furthermore a variable gap between a door and the frame will be very
noticeable - you can always spot a gap of 3mm one side and 6mm the other
side or in the middle. Leave too little clearance and any deflection of
the top will cause the doors to bind and too much clearance just looks
naff.

One trick is that you can double up on the thickness of the top by
building the 4 sides first and then inserting a 18mm piece of ply inside
of the top. This extra ply doesn't need to come right to the front - you
can set it back to leave clearance for the doors etc. The chances that
you will always view the cabinet from the top and this extra
strengthening will not be seen.Â* I had to do this once of a 3ft flatpack
unit when I used it to support a 2 foot fish tank , which is f****g
heavy when filled with water.

My home-made cabinet supported a fish-tank too - 5' long, 18" front to
back and 2' high. The glass itself was 10mm for the sides and 12mm for
the base, so it was heavy before filling! I estimated it be about half a
tonne once filled (allowing for the weight of glass and the water not
being to the top). I did check the floor joists first.

Whoever buys this house in the future will wonder what was going on, as
I used to have that tank and a 20 gallon tank, in the living room. To
keep the noise down, the air pumps (two, twin diaphragm pumps) were in a
kitchen cupboard and there was an air ring-main under the floor, made of
40mm, plastic, waste pipe. Under the floor they will find a D-shaped
loop of waste pipe, with eight (hardly visible) holes where feeds and
take-offs were connected.

Only the waste pipe remains, as the tanks had to go once we had 3
children and space was at a premium.