How to build a casting mold with planks?

[U&D]

Planning to build a form for a 15 cm wide, approximately 3-meter-long, and up to 140 cm high wall (on sloping bedrock) and received a tip to use raw lumber instead of form plywood.

How close do the horizontal nail battens need to be?
How close should be the vertical battens with braces?

I welcome tips on the approach!

 

[schlump]

Read this thread, there's a lot of information: https://www.byggahus.se/forum/threads/gjuta-vaeldigt-stor-blomsterlada-i-betong.372580/page-7

• Unclear if it will be easier with råspont, probably depends on how "curvy" the rock is.
• If you use panels, you get a different surface than with råspont.
• If the bottom of the wall is not meant to be visible, you can pour a footing wider than 15 cm, making it easier to pour the rest of the wall on top, and the footing doesn't need to be placed so precisely. See linked thread.
• It is possible to drill into the rock and secure studs and other elements with expanders or similar.
• A horizontal stud at the bottom can be fastened/held in place with, for example, rebar drilled into the rock.
• Drill into the rock and fasten dowels and/or standing rebar with chemical anchors.
• Consider how to drain water that will run towards the wall.

I'm not an expert, but that's how I've done it, and my wall is still standing (the house on top as well).

 

[U&D]

Thank you very much!