How Long Should Concrete Stay In a Mold?
Vložit
- čas přidán 21. 08. 2024
- When making concrete or cement mortar castings, knowing when to demold them could mean the difference between success and failure. If you try to remove a concrete casting from a mold too soon, it could break if the concrete has not hardened (cured) enough, especially if there is small or fine details.
Knowing when to demold your concrete casting will be unique to each project and things like the mix design, the shape and thickness of the concrete poured and the ambient temperature are just a few of the variables that play a part in knowing when to remove the concrete casting from the mold.
Letting the curing concrete for at least 24 hours will let the concrete get to about 35% of the finished strength. This is often enough to demold the concrete, but if there is are small or fine details, 35% may not be strong enough to keep those little its from breaking during demolding. At 72 hours (3 days), the concrete is just a little over 60% of the way to its full finished strength.
So, there is no perfect time or set time to when exactly concrete should be demolded but this video should be able to give you an idea of how to judge your project and when your concrete is ready to be removed from the mold.
Referral links to products featured in Creating Concrete videos - As an Amazon Associate I earn from qualifying purchases
amzn.to/3vtmang - interlock stone mold
amzn.to/3VIEmDX - universal mold release
amzn.to/3TQ9e30 - silicone mold release
amzn.to/3J7Q2II - sonite sealing wax
amzn.to/4cDYz3T - Quikcrete red pigment
amzn.to/4cIlDOK - Quikcrete brown pigment
amzn.to/43EuVHL - Quikcrete charcoal pigment
amzn.to/3J0MLee - Quikcrete bonding adhesive (PVA)
amzn.to/3xlzwlW - Quikcrete bonding adhesive 4L (PVA)
amzn.to/4aiGGGg - Sika acrylic fortifier 4L
amzn.to/3vqjdUw - Drylok hydraulic cement
amzn.to/3J3aDhv - Bosch mortar mixing drill
amzn.to/4aiwQUS - 4.5" diamond cup wheel
amzn.to/4aisWvb - mortar mixing paddle whip
amzn.to/49nsDOq - Budget mortar mixer and paddle
amzn.to/4ayjR1z - Sea sponge set for texturing
amzn.to/3xvpE96 - Masonry / grout sponges
amzn.to/3TGrZ8H - Marshalltown margin trowel (rubber grip)
amzn.to/3VEhntP - Marshalltown margin trowel (wood grip)
amzn.to/3xujXbx - Marshalltown point trowel (rubber grip)
amzn.to/3TCp9Se - Marshalltown point trowel (wood grip)
amzn.to/4ale5A4 - Marshalltown 12" square trowel
amzn.to/4aEsUNI - 16" pool trowel set
amzn.to/43H3cpO - powdered concrete pigments
amzn.to/4avz2Is - fine sponge float
amzn.to/4cFsYPi - 5 gallon mixing bucket
amzn.to/4cyIKeG - bulk acrylic paint set
amzn.to/4aB9oBU - airbrush and compressor kit
amzn.to/3U29Y6c - high range water reducer
amzn.to/3TGModV - fiberglass reinforcement 3/4" strands
amzn.to/4cEd87w - alkalai resistant chopped glass fibers 3/4"
amzn.to/3J0YzNR - perlite 4 cubic foot bag (coarse)
amzn.to/3xiCYxI - vermiculite 4 cubic foot bag (coarse)
amzn.to/43H2xV8 - Aircrete FM-160 liquid foam maker
amzn.to/4aHPFk9 - RTV 100% silicone (10 pack)
amzn.to/3VKbWcS - Smooth-On Vytaflex 30 urethane rubber
amzn.to/3xiEhg6 - Smooth-On skin safe liquid silicone rubber
amzn.to/3VE04cj - slate texture skin
amzn.to/3J0QEAb - bluestone texture skin
amzn.to/3xmZfdR - basalt texture skin
amzn.to/4aFjSQE - Variable speed wet grinder step sanding kit
amzn.to/43I090s - 4.5 cubic foot cement barrel mixer 0.5hp
#CreatingConcrete #cementcasting #DIYcement #cementcrafts #DIYconcrete
Great information. Thanks again.
Hi Steve. happy to subscribe. i’ve been enjoying and learning tips over the holidays and look forward to new ideas. good luck.
BTW. I am using 3d printed mold made from PLA plastic. I've feeling that either cement or moisture in it is corrosive for PLA and is making the mold milky matt, brittle and deteriorating rather quickly after few uses. I guess it kinda makes sense, since PLA is acid and cement is strong base. But it's just something that i've found. Probably might be alleviated by using thicker mold release or completely fixed by using PETG plastic instead.
Firstly I want to thank you for your videos they are so helpful, secondly After spray misting a small project the first 2 or 3 days , can I then wet cure it in a pan of water? I just learned about wet curing today from watching your videos.
When we cast in West Africa we always wet cured. I would walk along the line of moulds with a hosepipe twice a day. It’s standard practise in Africa to cure like this. We were casting blocks for building
If it's in mould for 3 days how do I keep it wer
Hello Steve, I've been searching on the internet and can not seem to find the answer to my question.
Fisrt, my goal is to reduce shrinkage of mortar and concrete to as much as possible.
Heres the question. If using a bonding admixture or acrylic admixture can be used a 50% of the water, can I not add water reducing admixture to further reduce the content of water in the mix so to reduce double fold or eliminate the shrinkage that happens when water leaves the mix over time?
And bonus question. Access to acrylic fortifiers is cost prohibitive or outright impossible for the small player, but acrylic paint primer for concrete is plentiful. Can it not be used as a substitute? The acrylic paint primer is a milky liquid that is used for roofing impermiabilization, it's almost like water. I've heard of people having used it to form a "crystaline coat over roofs" when it leaks, usage is instead of water use that with Portland cement.
I approve the answer by experience
Submerge it water for 28 days!!! WOW!
Unicorn farts, eh?