3D Printing Forum

Wonder if he got it working

I'm not sure about the welded steel frame, I think I would have gone for aluminium alloy star linear sections and brackets to allow for accurate positioning and squaring of elements, a 30x30 or 40x40 section would be a good section and would allow for easy insertion of side panels etc.

Well, steel is cheap, and it has almost 0 warping (elongation) between 20 and 60 °C.
But I wouldn't want to have to weld it myself - achieving the necessary tolerances for the frame. I hear steel warps and shifts while welding. Not sure I'd want to mess with that...

My upcoming printer build will have a steel frame as well, but a bit different. It'll be lasered stainless steel sheets (2.5mm probably) which mount together just like the UMO. But I want to get rid of the screws and mount the sheets together in another way. I was thinking of having them TIG welded at the anchors by a professional shop. Or maybe I try this:

Left side shows the joint parts before fixing them, and on the right they are fixed using a chisel to deform the anchors and lock them in place.
The anchors are slightly protruding (0.5mm here)

Section view shows how the deformed anchor is held in place.

All you need is a hammer and a chisel - both cheap tools.
Lasercut stainless steel sheets are surprisingly not that expensive, especially if you have more than one unit made.

/edit:
I know the chisel's angle doesn't match, and there are other mistakes in the pictures. But these are just very quickly made mockups to show you guys the idea. With some refinement, this could actually work.

What do you think?

/edit:
It would not look very pretty, that's a drawback... But how important is that compared to lowering the unit's price AND increasing the quality?

/edit:
Another drawback: Once the parts are joined, they are joined for good (as would be the case when welding them). But I can always use screws for some parts that need to be removable, should there be any.

/final edit:
By the way, I don't think that I'm the first person to think of this. Does anyone know if this is a common method and how it's called?
For example, I know that lumber axes' heads are attached to the handles in a similar way, although there you usually put a wedge into the shaft and leave it there. Still, that's how I thought of this..

/did I say final edit?
http://www.instructables.com/id/How-to- ... le-an-axe/

I would just do some TIG fusion tack welding at the end of each anchor, it puts very little heat into the material, so you get very little deformation problems compared to welding longer sections, and it works great on stainless steel!

Meduza wrote:I would just do some TIG fusion tack welding at the end of each anchor, it puts very little heat into the material, so you get very little deformation problems compared to welding longer sections, and it works great on stainless steel!

Thanks, I think we can agree that this would be the best solution - but you have to be able to TIG weld (or have it welded). Either way would cost quite a bit. I wanted to buy a TIG welder, but these things are either crappy or really expensive. Would be great to be able to choose between either of two good methods...

I have seen a number of good reviews about this one:

https://www.amazon.de/dp/B00GWIDKJW/ref ... azbYQXDXJC

Can be used to weld aluminium too (AC mode).

Do you know how much power this thing draws from mains? I've looked up several models but not a single one specifies power draw which is kind of ridiculous...

Since it is "only" 230V, I would think that it needs somewhere between 10-16A, maybe even less. I currently only have a very old stick welder and that one has welding currents up to 120A I think and works fine on a regular outlet with a 10A fuse.

It draws about 16A at max current, but if you run it at lower currents you can probably run it just fine at a 10A fuse.

It is not the best machine, china made and exists under a infinite number of brands, but it is usable for some hobby welding. There is some newer models from the same manufacturers (pictures below) that is supposed to be better, but i have not heard as much about it.

Well the regular Swiss AC plug with 3 round pins (same as EU plug but with a third pin for earth) is specified for a maximum current of 13 Amps, and can not be fused above 13 Amps (at least not in a regular, certified house installation). If you want 16 Amps, you need the beefier mains connector with rectangular pins. And anything above would be larger sockets and / or 3-phase systems.

So if these machines have a (one) regular 230V input, I should be fine. But anything above that is not allowed in Switzerland and therefore will trigger the circuit breakers.
Well maybe I get one some time. I think that for now I would just bring my frame to a local metal shop. Costs less than even the cheapest machines, and you get professional quality with no learning curve

The Stahlwerk welder that @Meduza mentioned is sold in Switzerland, maybe they can tell you what plug they use.

It says it has the German SchuKo 16 A plug. If it actually draws 16 Amps, it will overload any standard Swiss system. Even if it doesn't throw out the breakers, it would still overload the infrastructure (wiring, clamps, terminals...) when used over longer periods of time.

Well, I want to add a 16 Amps socket (the squared one) to my workshop anyways for the CNC machine. I could make it two, and be prepared to have that welder.. For now it's too expensive. I think a local shop can put my prototype together for under 200$ which would set me up for a while.

It will not draw 16 amps unless you turn the amperage up to max, so a 13A circuit will work just fine if you limit the max current yourself.

I asked Stahlwerk and they say it will draw max 16 amps but as Meduza says, that is only if you use the full 200 amps welding current.