How Hard is it to Pour a Concrete Mold…..
- Concrete Mix
Use a Sacrete or Quickcrete Concrete Mix ( with small stone). - Mixing Bucket, wheel barrow, or mixer
- Shovel to Mix with
- Water
- Lubricant -
You will need to use a mold release. Castor oil or vegetable oil
8 parts Denatured Alcohol & 2 parts Castor Oil
Directions
1. Prepare Mold :
Apply mold release with a fine spray on the mold and wipe
it slightly with a cotton rag.
2. Mix Cement:
Follow directions on the back of the bag. Your mix should be wet enough to a consistency of a stew. After a few pours you will find ” A Recipe” that works for you, then stay with it.
Mix very well. Mixture needs to be smooth, neither runny nor dry or lumpy but don’t MAKE IT SOUPY.
Be careful withe the last little bit of water as it can go from perfect to wet very quickly with a little water.
3. Pour cement into Mold:
Pour half of the mold first. Now shake and tap bottom & sides of the mold to eliminate all bubbles.
Fill the rest of the mold up with your cement mixture.
Shake and tap again until the top surface is flat and even.
Keep mold in a dry area for 24 hours on a level surface.
YOU CAN USE A RUBBER MALLET TO TAP THESE MOLDS
4. Unmold:
Now comes the best part as you get to see you end product. Turn the mold upside down onto a flat surface, and open up the fibreglass casing and remove the rubber. Be gentle with the concrete item as it will still be “green” and fragile. The concrete will take an additional 2 to 5 days to finish drying all the way through the item.
5. Clean-up:
Keep your molds clean. Wash with warm soapy water, rinse well.
HAVE FUN…
on February 9, 2010 on 12:54 pm
Hi, I have made alot of slabs for a friend, but around the edges on quite a few of them, the slabs have crumbled. He did have them before they were fully cured, and then we had alot of frost and snow. Would this have been the reason for the crumbling? He also had poited them up with “Pave Fix” a silicon type hard setting crout and i noticed that the crumbled slabs are only where he had poited up, the others seem fine. If the slabs were not cured properly would there have possibly been an reaction with the crout. Thanks I look forward to your reply. Jamie
on February 10, 2010 on 12:35 am
HI Jamie
It sounds a bit like you applied too much release agent which did not allow the cement to cure. Since the top edge of the slab is the bottom corner of the mold, th e oil may have pooled in the corners of the mold. Probaly not much you can do with these and you may have to replace them.
Tim
on February 10, 2010 on 1:27 pm
Hi Tim, Thanks for your reply. I do try to take care when applying the release agent. I use a cloth to rub it in and any excess is wiped away with a dry cloth. I have to tell you that around 50 slabs have crumbled around the edges!!!Thats alot.
It seems to be one whole batch made at the same time.
He has had around 400 of me to date and needs more, but i am worried about further slabs crumbling.
It really has worried me. I have made slabs now for over 3yrs and have never had this problem before.
Thanks Jamie
on February 11, 2010 on 2:13 pm
It sounds like your cement was old. If it had been sitting around, moisture gets to it and then it will not bind properly with the sand and stone.
on May 24, 2010 on 4:32 pm
what i have to do for avoid air holes from the molds
on May 24, 2010 on 9:58 pm
Hi Chris
I would suggest you read my blog article on Darn Air Bubbles http://gardenstatues.wordpress.com/2009/02/05/those-nasty-air-bubbles/
Tim
on January 3, 2011 on 1:34 am
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on March 7, 2011 on 3:42 pm
some years ago I was given some very heavy molds for molding yard ornaments, etc. No directions except I was told to line the molds with vaseline. To expensive to line these large molds so I used axle grease which seemed to be near the same stuff. I molded an Easter rabbit pulling a cart. The concrete all stuck to the molds and ruined the ornament. I don’t know what the molds are made of. They are white and very heavy. What release method do I use to release the objects from these molds?
Margaret
on March 8, 2011 on 12:19 pm
Hi Margaret, I am not sure what these molds are made from either. Try Murphys Oil Soap or WD-40
on August 21, 2011 on 4:03 pm
Hi, I’m new to the ornamental concrete business. I’m trying my hand at ornamental planters. I’ve only done two pours and both times the pots came out cracked. The mold is made of urethane rubber with a fiberglass mother mold. Water leaks from the mold during the pour. Can you tell me what I might be doing wrong? Thanks
on February 13, 2012 on 4:34 am
[...] How Hard is it to Pour a Concrete Mold….. Well here is a topic I get asked all the time. How hard is it? My answer: As easy as baking a cake! You take some dry ingredients, add water, mix to right consistency, and then pour into a mold to set.. Ok the dry mix is a little heavier and you may use a [...] [...]