Backyard Aquaponics
A place to discuss aquaponics

I was thinking a big bit of solid, perhaps 25mm or more, welded on, not a bolt.
But it's too complex.
The problem with using plastic feet, is that the contact angles are different for every single bed. my Driveway was built by an idiot, it's all over the place. Each would need to be hand crafted to suit it's placement.

no veebs, not yet, but i have aquired the argon bottle and have it pretty much ready to rock. now if i could only stop friggin around with fish and tanks...........

Ok, sorry boys, i just seen this thread, where to start..

Alright veggie boy, what material are you welding, is it coated in anything, because this could be causing your welder to struggle at 50A, though i believe that sounds low anyway. If not think about when your welding, your angle, speed and height of the wire/stick to your project, get these right and you'll have no problem. If you want some more info, let me know, i have some stuff at school that might be useful.

As for the bracing, well industry use 600mm centers and thats what we did with TimC's, also we cheated in our design by bringing the overall base inside that of the grow bed by about 50mm, as TimC mentioned. It helps distribute the weight, but i think you have to be mindful of the size of the material again, we used 40mm square, i think anything less than 30 and there would be too much pressure and the weight could crack your grow bed.

Did i cover most of it??? hope so, finally feel like i have something to contribute to the forum

I just seen you other bit on my thread, what you mean not have enough power when the project gets bigger veggie boy????

Hey Kuda, another idea is to cap the ends and weld a large nut into a pre drilled hole, you can then put a bolt into this nut. It also means you wont have to worry about cutting the legs as you will literally have to just tighten or loosen the bolt to get the height you want.

My welder max is 130amps. I find that even with the angle iron stands - which in the whole have less metal than an RHS one - by the time I have welded up the top of the stand - including cross supports and start welding the legs, the size of the work (ie amount of metal) makes it difficult to get the heat into the metal that I need to get proper penetration. If I don't go at it really hard - which normally results in a pretty ugly weld with a fair bit of carbon too - and also preheat the metal in the sun, then penetration is insificient and the leg and weld will easilly come off the rest of the work.

Also veggie boy, i think the cross bracing on the legs is over engineering and only a necessity if you have a tall grow bed.. ..but then that means you'll need a ladder to get your vegetables when they are fully grown too!!!

How permanent do you expect your system to be KP and is the place yours. If it is yours and you intend it to be fairly permanent - I'd be inclined to do some concret work where each leg is going - probably a bit of a peer would be easiest :-)

JJ are you saying you don't think it's important that the angle of the concrete is not perpendicular to the angle of the leg?

I had considered using allthread, but was seriously advised by the welders at work, not to extend more than 50mm... and the variance is greater than this, so I'd still need to cut them all different lengths.

Do you have any suggestions as to getting nice traction on the ground? As per my diagram above? This is my biggest issue.

i see what your saying, well in my experience at the school, if your having a problem with penetration then either the welder is not set up properly (this is like 99% of the time) or your earth lead is too far away from where your welding.

I believe a 130A welder will do fine. I know the welder i used at the school is much bigger, but i never had it above 100A for the whole project and we where welding duelgal, never had a penetration problem.

I agree the cross bracing may be overdoing it a bit. It is really to protect against a major knock, remembering that the first of my grow-beds was set up on a concrete skirt that is outside my shed and sometimes has car traffic on it. Despite my talk about welding issues - the welds on my beds are extremely strong, I have seen to this, and the beds are tough as. All the weight is downwards - so the likelyhood of losing the legs sideways is nil without a major knock (like a card driving into it at fair speed (a very unlikely occurence I guess). I may even end up removing some of this bracing on the barra system stand (the one I linked to above) because it is just behind the shed on a dirt area and the bracing has kinda limited the way I wanted to place the troughs/tanks I am using as sumps for the system.

Thanks JJ - will try putting the earth lead closer next time - this might be what I've been doing wrong when doing legs. I'll generaly have it attached to one of the cross supports - which are I guess at least 50 or 60 cm from where I am welding.

VB,
the driveway is already concrete.
I would have assumed that to put a pier, I'd have to damage the existing concrete, or they wouldn't stick...

I have almost 0 experience with concrete, so need heaps of help here.
I own the house
We may sell in a couple of years, probably 3-4
I'd hate to try and sell a driveways with lumps of concrete I can't remove easily on it.

If I do make 'piers' I assume you mean like small square pads to place the leg on. How do I stop them breaking off?
Would I drill the driveway and put in a couple of spies of reo, then box up and pour in some quickset? do I need to use slowset ready-mix?
How would I box them up neatly so I can screed off the top? Do I have to make individual wooden boxes for each leg cos they're all on different angles?

Edit: PS with beds as tall as yours ot TimC's, I wouldn't expect that a car would have to be traveling fast at all if it had a GB full of gravel and (worst case) water.
A parking bump would flatten it without bracing.
But, if they can't be bumped by a car, and aren't on uneven ground or the side of a hill (like mine) they wont fall. I shouldn't expect

that sounds good.. the other reason for not having the bracing with our set ups was it allowed us to access the space under the grow bed (which is where i put my fish tank). Robyn and myself have limited horizontal space, or more so a odd size space - long and thin.

I think the horizontal space is what dictates what you can and cant do, you think thats a fair statement???

Yeah, thats a good idea veggie boy, a good contact close to where your welding is ideal. When i welded the stands i had it about 40mm away sometimes. Be mindful though that a good contact is better that getting it close to your weld, especially if your welding coated metal. Its a DC current and the shorter path allows more current with less heat loss, but its no good if the contact is poor, you'll just get nothing.

Let me know how you go