Non sticking shuttering

[czechmate]

For grain walling I am going to pour some 8” concrete walls. For the shuttering I intend to make panels out of 9”x3” boards (mainly because I have a job for them afterwards). It will just be saw, not planed. Will it just come away easily or is there something I should sprinkle onto the wood before pouring the concrete?

 

[RWG Contracts]

For grain walling I am going to pour some 8” concrete walls. For the shuttering I intend to make panels out of 9”x3” boards (mainly because I have a job for them afterwards). It will just be saw, not planed. Will it just come away easily or is there something I should sprinkle onto the wood before pouring the concrete?

you’d be better using proper shuttering plywood

 

[Pan mixer]

I use marine ply now as it will do 50 plus pours per side without falling to pieces. I paint on soya oil (as I have a couple of IBCs of it for pig feeding in the yard), comes off fine. Mould release oil may be better.

 

[Richy12]

Oil/diesel/release agent will be fine.

The surface finish/how smooth it is depends on the timber used. "Fair faced" timber is more expensive obviously.

The multiple joints in the timber I would be worried about also. The weight of the wet concrete may "splay" the boards at the joints over large shutter pans if not braced fully.

 

[czechmate]

Thanks for the replies
Yes, I intend to use a few braces.
I was also a bit concerned about leakage into the joins making the panel hard to remove - an idea today, I could attach a plastic sheet to it?

 

[Pan mixer]

Thanks for the replies
Yes, I intend to use a few braces.
I was also a bit concerned about leakage into the joins making the panel hard to remove - an idea today, I could attach a plastic sheet to it?

yes you could as long as you have a fully qualified nurse with you to make sure that the platic sheet is drum tight (like a hospital bed used to be) or else you will have wrinkles, the sheet wants to be thick enough to not tear though as you will be pouring in an abrasive mixture, also don't use the concrete poker too close to the side as that will tear it too. Probably 400 micron would be ok.

The surface will then end up like glass, it will easily reflect a torch beam for instance and you will be immensely proud.

After a year or two the surface will look just like any other.

I have this particular tee shirt, I used sheets of stiff plastic to face my plwood in a bunch of weaner sheds where I wanted the walls as smooth as possible for washing out purposes, even the outside walls that are not power washed every month are the same as all the others now.

 

[DanniAgro]

Used shutter releasing fluid painted on the shuttering last time I did it, but it's just like diesel when you handle it...

 

[RWG Contracts]

70% diesel and 30% new hydraulic oil works best, just not on some sites as they don’t like it running down the drain