Open Source Concrete Work

Notes

• Get yourself a power trowel - [1]
• Polymesh F is an extra $5/yard for concrete work - [2]
• Fiber still requires rebar [3]
• Use Steel Fiber Concrete for strength - not available in many places.

Workshop Foundation

• 3000 sf build of prototyping area for the Seed Eco-Homes, for building a second workshop space, with various prototyping experiments from material production to large CNC machines, 2021. Large truss structure at Universal Prototyping Structure

Open Source Power Trowel

• Combo blade - that is what they have at Rentall
• This is their finish blade.
• In video below, they show float and trowel blades as separate?

Notes On Technique

• Source 1 - [4]
• Temporary screed posts explained here for larger slabs poured in sections:

• 14 foot sections are laid down, so it's convenient for a scree board. Work in 14 foot strips. Bull float follows right after screeding. But how do they keep the screed board level? This guy also sells a course on how to start a concrete business doing work like this.

• Extender truck or chute extender; pump truck otherwise. Here is a wet setting of edge rebar reinforcement:

Note also the height level rebar stuck in and cleared at 1:40 - to set screed level.

• Concrete stakes - metal with holes:

These guys above use screen boards put in at the right height - note Mike Day in last video doesn't do that - they set the level with the height set at 1:40 in the last video

• More slabs with screed board levels put in, as opposed to the level stake. Mike Day is much more elegant, not requiring the section boards. [5]. It looks like the skilled guys do the rebar stakes for level, the less skilled crews do the scree height boards?

Understanding Concrete Timing

In good weather - power trowel is about 2 hours after pour is finished.

• 35 yard slab
• 2 guys screeing, 2 guys behind them moving concrete around - 4 person job
• Batched at 6.
• Arrived on site at 7.
• Finished pour 8:30
• Start mag floats on edges at 10:20 AM
• Edger at 10:30
• 2:15 hours after pour ready to walk on, sinks about 1/8"
• Float blades first, finish trowel blades second. Take off the float blades to use the finish blades.
• Power trowel started at 11 am at 2.5 hours after start of pour - with float blades first. Only 1+ hour for power trowel.
• Notes: effectively, go from screeing step - to edger - to power trowel. Edger can be avoided. Power trowel does both float and trowel.

Links

• Roman Concrete
• Solar Concrete
• Concrete Cutting Blade
• Polished Concrete
• Lime Concrete
• Micro Concrete Roofing (MCR)
• Concrete Polishing
• Concrete Mixer
• Concrete Fasteners
• Rosebud Concrete Pour
• Concrete
• Concrete Foundations
• Concrete in Cold Weather
• Concrete Slab
• Reinforced Concrete Pipe
• Advanced Concretes
• Concrete 3D Printers
• Concrete Paint