Casting staddle stones, anyone tried it?

[El Barto]

I haven't done any concrete casting before but I was thinking of having a go to see if I could cast an acceptable staddle stone. Why not eh.

Has anyone tried it or anything similar? Can you help me out with techniques/mixes/what I need to buy etc?

Cheers.

 

[MikeG.]

This could be more awkward than you think. Because of the mushroom shape, you are going to have to A/ very carefully design your moulds such that you can get it apart afterwards, and B/ take great care to get the concrete into the very depths and corners of an awkward shape mould, without being able to see whether or not you've succeeded until afterwards. You will also be turning/ manipulating something that is pretty heavy.

Will this be load bearing, or is it just for decoration?

 

[Trainee neophyte]

I have done a bit with hypertufa, which looks like it may be appropriate here. Firstly, do you want them as a garden ornament, or will you actually balance a hay rick on top? I would assume not load bearing, so hypertufa will be fine.

I used a mix of one third by volume cement, pearlite and compost, and they have been reasonably robust, with no major cracks or disasters. You can actually sculpt the stuff once it has dried for a couple of days, and you can make it like a mud pie, so no need for molds and fuss, as long as you are aiming for that roughly-chiseled granite look. Here are some that someone else made earlier:

Start here: https://www.hypertufa.net

 

[Tris]

There's a place just up the road from us that casts various garden stuff and the bird baths they do are a similar thing.
If you use one mould for the top and one for the pedestal you can do it easily although the commercial places use a vibrating table to remove air bubbles and get a smooth finish on what will be the external surfaces.

 

[Woody2Shoes]

I haven't done any concrete casting before but I was thinking of having a go to see if I could cast an acceptable staddle stone. Why not eh.

Has anyone tried it or anything similar? Can you help me out with techniques/mixes/what I need to buy etc?

Cheers.

Are these for decorative or structural purposes?

In any event, I'd probably cast them in two separate pieces - the top piece with a bit of rebar in it to connect with the bottom piece.

Vibration (a battery hammer drill on roto-stop with the chuck closed pressed against the mould?) will help elimimate air bubbles, but overdoing it may start to stratify the aggregate particles.

Standard concrete is basically 'ballast' - a graded mixture of small stones and sand plus cement. Follow the instructions on the cement pack, but normally 1 scoop of dust to three or four scoops of ballast would be a good strong mix.

 

[El Barto]

Ahh sorry guys, I should have been more specific, completely forgot about traditional staddle stones! I was actually thinking more along like the lines of this shape:

 

[Blackswanwood]

I had a look at doing this but concluded it was easier and would look better to just buy them made from stone. I asked a local stone merchant and they made them up for me at £30 each.

 

[The_Yellow_Ardvark]

On the top, don't worry if it looks rough, it will help with moss and other rock plants to set up home.

 

[Trainee neophyte]

Ahh sorry guys, I should have been more specific, completely forgot about traditional staddle stones! I was actually thinking more along like the lines of this shape:

Easy! Make a ply box with all the screws facing out(!), coat the inside with oil, slap the concrete in and give it a really good thump all round to get the air out. A vibrating sander can help with that. Use white cement and coloured dye powders for posh effects. Use silicon on all the inside corner edges to give you a beveled look. White melamine chipboard releases well, but use oil as well. Ply will last longer if you want one mold to do many blocks. You could use some steel mesh inside if you wanted to, but I think it would probably be strong enough without. I would give each one a day to cure, then dismantle to mold to release, and cure the freshly made block in a bucket of water for two weeks. A garden pond will also work (your fish may object to pH changes).

You can also make a little bass-relief motif by putting the design on the inside edges - I used strips of ply to make a Greek key / meander but this makes getting the mold off afterwards more tricky.

Regarding the oil, I mostly used olive oil, but used standard engine oil or chip pan oil will work, as will fresh cooking oil of any variety, and theoretically used engine oil, but I wouldn't do that, personally. Nasty mess.

Edit: I forgot to mention that your design calls for compound mitre :shock: :shock: :shock: joints. Nothing to worry about.

 

[The_Yellow_Ardvark]

I have done a few in my time.

Using decent timber make a frame 3" bigger all round than the top you aim to cast.
If using an original saddle cap, fix a handle to it.
This will allow you to lift it into the mould and tap free.

Support the stone in the casting box and pack hard round it soft sand. Until it supports its self.
Then fill the rest with sharp sand, packing well as you go.
Remove the mould and make good any small defects in the sand.
Using 4 to one of sharp sand to cement fill the mould to about 2" deep, leaving it rough.
Then fill the rest with 3/8th to dust concrete at 5 to 1 mix.
Level with top of box.

If making your own the size was.
1 fore arm long plus 4 fingers.
The height was 2 hands high (8 fingers) and 2 to 3 fingers high at the outer edge.

The base was knee high, with a square top, one hand from wrist to finger tip wide.
The base 2 hands wide, finger tip to finger tip.
Make your mould and support it, base of the column to the bottom. Make sure you can dis mantle it.
Oil or tallow the sides.

Same mix as before fill the , but you will need 3" at the top and no more than 1.5" of soft sand on the sides. The fill the rest with the 3/8 to dust mix.

In the past they saddle was not fixed to the stone. This allowed the Rick or barn to move with out toppling the stone.

I would use 12mm Re bar in the saddle on column to hold it together now.
Hope this helps.

 

[El Barto]

Ahh sorry guys, I should have been more specific, completely forgot about traditional staddle stones! I was actually thinking more along like the lines of this shape:

Easy! Make a ply box with all the screws facing out(!), coat the inside with oil, slap the concrete in and give it a really good thump all round to get the air out. A vibrating sander can help with that. Use white cement and coloured dye powders for posh effects. Use silicon on all the inside corner edges to give you a beveled look. White melamine chipboard releases well, but use oil as well. Ply will last longer if you want one mold to do many blocks. You could use some steel mesh inside if you wanted to, but I think it would probably be strong enough without. I would give each one a day to cure, then dismantle to mold to release, and cure the freshly made block in a bucket of water for two weeks. A garden pond will also work (your fish may object to pH changes).

You can also make a little bass-relief motif by putting the design on the inside edges - I used strips of ply to make a Greek key / meander but this makes getting the mold off afterwards more tricky.

Regarding the oil, I mostly used olive oil, but used standard engine oil or chip pan oil will work, as will fresh cooking oil of any variety, and theoretically used engine oil, but I wouldn't do that, personally. Nasty mess.

Edit: I forgot to mention that your design calls for compound mitre :shock: :shock: :shock: joints. Nothing to worry about.

Thanks for this and for everyone else’s replies! Really useful. Would that ready made concrete you can buy from Wickes do the job? Otherwise what mix would you use for the white concrete? Cool idea about using dyes and stuff...

 

[Woody2Shoes]

Would that ready made concrete you can buy from Wickes do the job? Otherwise what mix would you use for the white concrete? Cool idea about using dyes and stuff...

Don't know - you still haven't said if this is structural or decorative - with the premixed stuff you have no control over what aggregate has been used. Often the premixed stuff is designed to go off quite fast (e.g. Postcrete), which may be a disadvantage.

If you want white cement then Snowcrete would be a good bet. https://www.diy.com/departments/blue-ci ... 716_BQ.prd - follow the manufacturers instructions but usually one dust to 3 or 4 ballast. You could make your own ballast mix with the right sand and grit/gravel. You could polish/scabble the cast faces with an agle grinder or a scabbler to get a different finish - sort of like Terrazzo https://en.wikipedia.org/wiki/Terrazzo

 

[Woody2Shoes]

Here's a bloke doing a flattened version of what I think you're after: https://www.youtube.com/watch?v=ibww7NHmjj8

 

[El Barto]

Thanks for that. These would ideally be structural, for things like oak porches and such.

I was thinking this sort of stuff: https://www.wickes.co.uk/Blue-Circle-Hi ... g/p/133771

 

[Trainee neophyte]

What Mr2Shoes said re white cement -I have some German brand available to me - I don't know what is for sale in the UK. Cement is very easy, and you can play around with small amounts to practice. My youngster has a thing for cactuses, so any leftover cement gets made into wobbly, slightly off-centre plant pots. Try different aggregates, different mixes - play with it. The worst you can do is make some hardcore infill by mistake. My driveway contains many an experiment.

 

[MikeG.]

Thanks for that. These would ideally be structural, for things like oak porches and such........

In which case, don't stick one bit of rebar out of the middle of the top. Either make it two, or have a plate with some bolt-sized holes poking out. As you know, the unrestrained bottom end of an oak post is going to want to twist, so you need something to resist it.

 

[El Barto]

Thanks for that. These would ideally be structural, for things like oak porches and such.

I was thinking this sort of stuff: https://www.wickes.co.uk/Blue-Circle-Hi ... g/p/133771

Any thoughts on this stuff?

 

[John Brown]

I know I'm resurrecting a two year old thread, but wondering how your staddle stones turned out. I just made a truncated pyramid mould, and I'm planning on casting a couple this weekend. Any tips re. concrete mix or anything else gratefully received.

 

[Spectric]

Line your mould with polythene for a smooth finish and use 3 soft, 1 sharp and 1 cement. When filled give the mould some taps to settle the mix in, if you have an sds chisel then use this against a piece of wood to cause vibrations which will give a nicer finish.

 

[John Brown]

No aggregate? I was planning on buying a bag of pre mixed stuff, as I don't need half a hundredweight of cement sitting around going hard.