Backyard Aquaponics
A place to discuss aquaponics

I've designed roads at 0.2%...so a 5mm bump in the kerb would cause pooling for 2.5m...needless to say contractors don't like building roads that flat

my favourite is the oil and gas industry, which is still in imperial units here in aus...apparently they have a unit of volume called a foot-acre

I think I fixed my foot problem.

if I weld the legs in situ then I can cut them to the right height.
If I weld a piece of angle onto the bottom in situ, them I can gaurantee the angle is right.

Anybody think this is a bad idea?

No - I think that is the best thing to do. Tis not like you are going to move them around - so just be sure you have them in the right place to start with. Is easy enough to grind that bit off in the future if you need to anyway.

I like your idea, If you want to maybe shift them around later consider this.

Think it would be a good idea if you downloaded the "image resizer" tool and used it Kuda

Roz I have it.
But it didn't require resize, and to tell the truth I didn't look first. I'll repost the image so the scroll bars go away

ROFL

Sorry KP, i lost my connection last night..

..yeah thats like 15%, thats heaps hey.. Im thinking you might get away with welding a foot on the bottom, like 100mm square say, then underneath put some of those plastic packers, i dont know what there called, but they use them when building concrete walls, to make sure everything is level, rekon you could turn one around and increase your angle. I'll find out what there called, one of the boys at work are bound too know.

What do you think ofjust welding angle iron on, on an angle as the pick shows at the top of this page? I'm quite partial to the idea. (already pricing material) or can you see a problem?

Not meant to be a stupid question.... but could the angle iron slip with the weight of a full growbed on a slope like you have??

Roz I wouldn't think so, but if advised I can weld some tracks on the bottom. give it some more traction. Maybe add longer bits of iron to increase friction. I wouldn't expect it to slide, with each leg being a different height, and the ground level changing all over the place, I imagine it wouldn't be able to move easily.
anyway, it's only 200kg per leg... i expect it wont move.

I think it could work KP, but you will need to make sure all the feet are parallel to the surface. Maybe tack them and then bend the tack to get it spot on..

..also i agree about increasing the surface area, would definitely help. Personally i would do it just for piece of mind

Let me know how you go

Shall do JJ, the beds arrived today
unfortunately, I just arrived in Shepparton
so this weekend, I'll sort out my design (I prefer to use a tape than other pplsCAD if I can help it) and hopefully do the bed parts at the shop, and finish off the legs at home.
Also I have to source some steel :-)

KP, if you remember your physics...weight and area make no difference.

Friction force is proportional to gravity force, but so is the force trying to push it down the hill, so the weight of the growbed makes no difference to how likely it is to slip.
Friction force is also proportional to area and pressure, but pressure is inversely proportional to area, so the contact area makes no difference to the total friction force, or how likely it is to slip.

Your only real parameters are the angle of the contact, and the riction factor of steel on concrete...to test, get a lump of whatever you want to use as your contact material, and try to 'surf' on it. Wobble and twist...if you feel safe, so will your growbed. If not, think about bolting your legs to the concrete.

Sorry if I misunderstood the problem

No steem no misunderstanding.
Currently my pine stand does not move (even when I wanted it to)
So I doubt I'll have a problem.

However. My physics is a touch rusty. Friction force = μN is it not?
So Fr = μma
Fr = μ*200kg*9.8m/s
So the weight of the GB has a lot to do with friction yes?

contact angle as per my weld in situ with angle iron will be 100%

If I increase the surface area of the angle, μ will change will it not?
I was certain μ was a constant that was different for all different materials and textures...

perhaps the size of the pad is irrelevant, I'm not sure about that one.
The size of the pad however make me feel easier about the moments where the leg is joined to the bed.