Polycarbonate sheets for home made cold frame

Supercell

I have some old floorboards I'm going to repurpose into a frame for a cold frame. with 3 kids polycarbonate is probably the way to go for the top.

My greenhouse has that double layer polycarbonate stuff and its fogged up and in in places has moss growing though it so want something solid this time.
I'm looking at this getting something like this chopped into two - https://365plastics.ie/polycarbonate-sheets.html?polycarb_sheet_size=5453

Has anyone ever used this stuff, or have any caveats I should consider - is this stuff likely to turn milky white over time, will it block parts of the light spectrum plants need to grow?
Have never made one of these but looking at youtube they seem simple enough to construct, any and all advice welcome.

enumbers

I have used similar on a greenhouse which I built 4 years ago and its still clear and in good condition. cuts ok with a high tooth count blade on circular saw.

Markcheese

Supercell wrote: »

I have some old floorboards I'm going to repurpose into a frame for a cold frame. with 3 kids polycarbonate is probably the way to go for the top.

My greenhouse has that double layer polycarbonate stuff and its fogged up and in in places has moss growing though it so want something solid this time.
I'm looking at this getting something like this chopped into two - https://365plastics.ie/polycarbonate-sheets.html?polycarb_sheet_size=5453

Has anyone ever used this stuff, or have any caveats I should consider - is this stuff likely to turn milky white over time, will it block parts of the light spectrum plants need to grow?
Have never made one of these but looking at youtube they seem simple enough to construct, any and all advice welcome.

Yup , used it .. bought a sheet of it last year for work ,
It wasn't cheap , I think I got the 5 ml stuff , and it was about 350 quid .. I'm struggling to remember how big the sheet was ..
The one I bought is supposed to be uv stable ...

garv123

All the Polycarbonate we use on a daily basis is UV protected.
Polycarbonate will scratch much quicker than acrylic (perspex) so it depends on what will be in contact with it.

When you take the covering off, use Mr. sheen and a clean micro fiber cloth to give it a polish and it'll take the static off it to stop dust sticking as bad.

Cleaning with any form of brush or rag will result in small scratches all over it.

blackbox

garv123 wrote: »

All the Polycarbonate we use on a daily basis is UV protected.
Polycarbonate will scratch much quicker than acrylic (perspex) so it depends on what will be in contact with it.

When you take the covering off, use Mr. sheen and a clean micro fiber cloth to give it a polish and it'll take the static off it to stop dust sticking as bad.

Cleaning with any form of brush or rag will result in small scratches all over it.

I think you've got that backwards. Polycarbonate is much more scratch resistant and stronger than perspex - that is why it is used for visors etc.

garv123

blackbox wrote: »

I think you've got that backwards. Polycarbonate is much more scratch resistant and stronger than perspex - that is why it is used for visors etc.

I really dont have it backwards.. Trust me we use it every single day of the week.

Polycarbonate is shatter resistant, but it is soft, and scratches easily. Acrylic, Which is what perspex is, is harder, and more resistant to scratches, but it will crack easily.

You can buy polycarbonate with a scratch resistant coating, which is more expensive, but will still get scratches.

Supercell

I'm not that bothered about scratching, its in the garden, its not going to be spotless one way or another but will wash it carefully, thanks for the advice. How thick should I go for, ws thinking of 3mm but not sure if that will be rigid enough to span a 50 cm'ish space?

Fern Bench

Supercell wrote: »

I'm not that bothered about scratching, its in the garden, its not going to be spotless one way or another but will wash it carefully, thanks for the advice. How thick should I go for, ws thinking of 3mm but not sure if that will be rigid enough to span a 50 cm'ish space?

I used an old folding shower door for mine. 10 euro on done deal. Still going strong after 5 years.

blackbox

garv123 wrote: »

I really dont have it backwards.. Trust me we use it every single day of the week.

Polycarbonate is shatter resistant, but it is soft, and scratches easily. Acrylic, Which is what perspex is, is harder, and more resistant to scratches, but it will crack easily.

You can buy polycarbonate with a scratch resistant coating, which is more expensive, but will still get scratches.

I stand corrected!

PCeeeee

garv123 wrote: »

I really dont have it backwards.. Trust me we use it every single day of the week.

Polycarbonate is shatter resistant, but it is soft, and scratches easily. Acrylic, Which is what perspex is, is harder, and more resistant to scratches, but it will crack easily.

You can buy polycarbonate with a scratch resistant coating, which is more expensive, but will still get scratches.

Is it Polycarb or Acrylic that's liable to go yellow then? We had a sheet of something for a tractor window one time and you couldn't see through it in the end.

Fine Cheers

Bought a couple of 6mm solid clear sheets for a lean to roof project from Plastic / Print Solutions Dublin. Both sides were UV treated. I think Star Plastics are another supplier and 365 as already stated. Not cheap but a great alternative to glass. Most suppliers will cut to size for you but you'll pay for the full sheet. Easy enough to cut and drill with suitable tools.

garv123

PCeeeee wrote: »

Is it Polycarb or Acrylic that's liable to go yellow then? We had a sheet of something for a tractor window one time and you couldn't see through it in the end.

Both if they are cheap stuff without UV protection. A lot of hardwares sell cheaper polystyrene sheets which will yellow too.