Concrete mixing tips at NB?

I want to make a small concrete slab for the CNC to increase rigidity. . I will use an 80lb bag of Quikcrete 5000.

Anyone have any tips in mixing concrete? Especially at NB? I’m thinking of trying to do it out of a trash bin.

Any brainstorms or tips based on stuff we have available would be appreciated. I dont want to spend more money than I have to and dont have a mixing tray. Never done it before but looks pretty straightforward except for the mixing part. I have the mold made since last night and plan to mix and pour tonight.


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There used to be a yellow mixing tray at the top of the shelves in the dirty shop. Not sure if it is still there. Just add enough water to make the concrete reasonably workable without the mixture getting too wet. I’d recommend watching some youtube videos about mixing concrete.

We should have finishing tools (ex: trowels) in the dirty shop in one of the crates by the drill press.

Above all this, I MUST STRESS, do not rinse anything with concrete on it into the sinks, toilets, anything connected to the plumbing system. The concrete will cure underwater inside the drains and clog the pipes. Scoop excess concrete into a trash bag and scrape the concrete off all the tools and mixing trays as cleanly as possible into the trash. Get a big bucket you can fill up 3/4 the way with water and wash everything in that bucket. Do not empty this bucket into sinks. Give the bucket time for the concrete to settle to the bottom, the water will turn mostly clear. The clear water can be carefully poured off, i’d recommend down at the street just in case. Then the settled concrete at the bottom of the bucket should be scooped into the trash.


Also If we have a random orbit sander in the dirty shop still, you can turn it on and use it as a vibrator around and against the outside of your form work to help the concrete settle.

(edit: also take off the sandpaper on the sander first, if any)

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Thanks just got your message! I will read it over when I get there and probably wouldn’t start till tonight! Uploading: 15640 aww


Thanks for the advice! I decided to wait until tomorrow but made some more progress on the mold and added rebar. I will create slotted cavities to accept the legs. The legs still need to be designed but the concrete slab part should be good enough to cast.


There is some spray mold release laying around in sparkle forge! That would probably help getting the concrete out of the mold.

Lol too late for that. I’m scared to disassemble it. Going to just wait a week while I work on the rest of the table stand.

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Its way stronger than it looks but not too happy about how crumbly it appears Cant get the wooden inserts out either. Going to have to burn them out I think. Plan is to embed nuts in the holes with epoxy… will probably seal the whole outside of the slab with epoxy if possible to protect it.