How to build modular raised garden beds?

[HappyDIYer]

I’m looking for a type of concrete block that allows sleepers to be slotted in and create modular garden beds. I seem to only see them being used in America. Do we have anything similar in Australia?

 

Alternativley, could I find wooden posts that have similar 4 grooves? If not, what’s the easiest tool to make slots like that on a timber post which would fit a sleeper.

 

I know Bunnings has some modular garden beds, but I like the idea of the concrete for added stability. 

[Noyade]

Morning @HappyDIYer 

"concrete block that allows sleepers to be slotted in"

Would you be interested in making them?

Concrete.

Bucket.

4-way timber jig.

Are your sleepers 50mm thick?

Do you know if they just 'sit' - or are they embedded into the ground?

We can't let the Americans beat us. 😁

I'd personally steer away from the trenched wooden members. I think with time the narrowed corners would split and separate?

Just a thought.

Cheers.

[JacobZ]

Hi @HappyDIYer,

Thank you for your question and welcome to the Bunnings Workshop community, it is fantastic to have you with us.
 

The equivalent products that are commonly used in Australia are joiner posts, end posts and corner posts. They are designed to be concreted into the ground and using a combination of the three types of posts, a variety of shapes can be made as long as the corners are square.

I can't say I've seen a concrete product like that before, but as @Noyade has said, I imagine you could make your own using a Bunnings 20L Pail Bucket, some concrete and some small pieces of a 200 x 50mm Treated Pine Sleeper to create the slots.

If you wanted to make your own out of timber, you could use a circular saw to cut 50mm wide and 20mm deep trenches along the length of a 100 x 100mm H4 Post. Note that this would likely be very difficult for a beginner.

Let me know what you think.

Jacob

[HappyDIYer]

Thank you both for your replies.

The DIY with the Bunnings bucket and jig is definitely an option. Would I need to line the bucket and jig with anything first?

Also, if I were to attempt the version with a timber post, would a router work to make that kind of square-ish groove? Is there a dado bit that easily makes the kind of shape for the sleeper to fit in?

[HappyDIYer]

Thank you @Noyade!

Yes the sleepers would be 50mm think.

The concrete blocks just sit on the ground. They have a hole in the middle for a rebar if you want to add one. But from what I’ve seen, most people don’t add one.

Let’s see how I go with your DIY suggestion. I’m sure it can be done - the Americans get everything so easy!  Haha

[JacobZ]

Hi @HappyDIYer,

There are specially designed formwork oils that would be the ideal thing for this application, however, I have heard that any generic cooking oil will also work well.

This Ryobi 5-Piece Straight Router Bit Set would be a good set for cutting out a 50mm wide rebate. You could use the 12.7mm bit to trace either side of your rebate, then clean out the middle with the 25mm router bit. 

If you were to attempt this, please ensure you take all necessary precautions including wearing eye protection, hearing protection gloves, and long work clothes. Routers can be extremely dangerous, so be sure the workpiece is well-clamped and use the guides on your router to get nice straight cuts. Take it slow and do it in layers as going too deep too quickly can overload the router and cause it to kick.

Let me know if you have any further questions.

Jacob