Perspex / Polycarbonate Crown Boards

[Cole lynch]

Any recommended methods for cutting 3mm polycarbonate sheet

 

[Erichalfbee]

Any recommended methods for cutting 3mm polycarbonate sheet

Fine tooth band saw.

 

[hemo]

If you don't have a power saw, then a 20/22 tooth generic diy handsaw will cut it. The cutting edge needs firmly supporting underneath to stop any cracking as you cut.

 

[Gilberdyke John]

Any recommended methods for cutting 3mm polycarbonate sheet

For crownboard size applications I normally use my tct blade table saw with the blade set shallow so the forces lie in the plane of the cut. Advance the workpiece slowly and keep your fingers out of the blade.
At a pinch you can use a hacksaw blade in a pad handle. Support the sheet while you work.

 

[Suzi]

I'm late to the party on this discussion and it has moved on slightly; but wouldn't kingspan encourage condensation?

 

[Erichalfbee]

I'm late to the party on this discussion and it has moved on slightly; but wouldn't kingspan encourage condensation?

Depends where you put it.
If you put it on the crownboard or in your wooden roof it makes the top of the hive better insulated than the sides. Water of respiration condenses on the coldest surface which is the corners and the sides where it can be used by the bees to use their winter stores rather than venturing out to look for water

 

[DonkeyDonz]

Maisemore sell them, various versions with or without holes.

Can you tell me if polycarbonate crown boards encourage condensation? I'm in East Sussex & we're high up so the only form of installation I use are bee wraps (DPM) primarily against green woodpecker

 

[Murox]

Can you tell me if polycarbonate crown boards encourage condensation? I'm in East Sussex & we're high up so the only form of installation I use are bee wraps (DPM) primarily against green woodpecker

Condensation occurs on the coldest surface - hence the common sense application of good insulation right on top of the polycarbonate if you use it - the thing that encourages condensation would be a lack of insulated 'warm' surfaces.

 

[Erichalfbee]

Yes as above. I have polycarbonate crowns with insulation on top. I usually get a little condensation in the corners that’s all.

 

[DonkeyDonz]

Condensation occurs on the coldest surface - hence the common sense application of good insulation right on top of the polycarbonate if you use it - the thing that encourages condensation would be a lack of insulated 'warm' surfaces.

I usually leave one of the Porter bee escapes open for ventilation, I have OMFs. If I place insulation over it how badly will that effect ventilation?

 

[Murox]

I usually leave one of the Porter bee escapes open for ventilation, I have OMFs. If I place insulation over it how badly will that effect ventilation?

Using an OMF you do not need any upper ventilation at all. That porter escape just vents out all the warmth (and granted a little moisture laden warm air) - remove the escape and close off the hole and put a good slab of 50mm insulation on top.

 

[DonkeyDonz]

Yes as above. I have polycarbonate crowns with insulation on top. I usually get a little condensation in the corners that’s all.

Can I use cut polystyrene as insulation, or what would you advise?

 

[jenkinsbrynmair]

I usually leave one of the Porter bee escapes open for ventilation,

Noooooooo!
Why do you think having a roaring gale ripping through the hive is good for the bees?

, I have OMFs. If I place insulation over it how badly will that effect ventilation?

You don't need/want holes in the crownboard for any kind of 'ventilation' it's a misguided fad initiated by a self professed 'expert' based on (his own) flawed science in the 1940's
Just close any porter holes, feed holes etc, block the vents in your roof and glue in a 50mm slab of celotex which can stay in the roof all year round.
Forget the 'wraps'

 

[pargyle]

Noooooooo!
Why do you think having a roaring gale ripping through the hive is good for the bees?

You don't need/want holes in the crownboard for any kind of 'ventilation' it's a misguided fad initiated by a self professed 'expert' based on (his own) flawed science in the 1940's
Just close any porter holes, feed holes etc, block the vents in your roof and glue in a 50mm slab of celotex which can stay in the roof all year round.
Forget the 'wraps'

Yes completely agree ... unless the DPM wraps are there to stop woodpecker damage ....

 

[Erichalfbee]

Can I use cut polystyrene as insulation, or what would you advise?

Yes that will do but you can use anything. Even an old cushion will do. PIR is best though

 

[DonkeyDonz]

Yes completely agree ... unless the DPM wraps are there to stop woodpecker damage ....

 

[DonkeyDonz]

Yes that will do but you can use anything. Even an old cushion will do. PIR is best though

PIR?

 

[pargyle]

PIR?

Generic name for Branded products such as Celotex, Kingspan, Recticel insulation materiasl often known as rigid polyurethane foam.

PIR - Polyisocyanurate

 

[Apiarisnt]

Generic name for Branded products such as Celotex, Kingspan, Recticel insulation materiasl often known as rigid polyurethane foam.

PIR - Polyisocyanurate

https://www.kingspan.com/us/en-us/a...ated-panels/blog-news/imprint-blog/pur-vs-pir

 

[Murox]

wrong button - apologies