AndyUK's Build - 1.2x1.0m Gantry

[AndyUK]

Great build!

Not sure if I missed it, but did you do any stress relieved given that you welded? If not, i assume residual stress would affect the structure overtime. I ve been asking this question on DIY facebook groups but havent received a good answer. Given that you are a physicist by trade I would love to hear your opinion on the matter.

Thank you!

One thing to think about is where the stress comes from - Its all about the cooling and contraction of the weld as it goes from hot hot hot to room temperature. This is effectively quite a short term process, once the stress is there, it will cause strain in the material resulting in some deflection. There isn't particularly any reason for this to change over the period of years.... And then of course, we go and epoxy level / scrape / machine the surfaces to make them flat, so that's all done once the strain is there and accounted for.

But always ground yourself in the practical world - its all too easy to get lost in theory and what-ifs. Experience trumps most of it. Plenty of people around here have welded frames, and I haven't seen anyone have an issue with stress. Just be sensible and tack weld everything slowly and move methodically around the frame to avoid building up heat too much before completing the full welds - but thats standard welding practice anyway.

[AndyUK]

Wiring Diagram update, to include new control panel switches, a 10W Diode Laser, and 4th Axis drive (Step and Dir lines not shown yet, but you get the picture).

Circuit Diagram v3.pdf

[Nickhofen]

Thanks for sharing .
Happy new year to you Andy!

[Lee Roberts]

a 10W Diode Laser

Cool, so your using the machine as a diode laser engraver? Been thinking about this recently myself too

[AndyUK]

Yeah, just a bit of a experiment really. £130 for a 10W 450nm Laser Tree 80 24V from their AliExpress store.

Made the first couple of cuts tonight - was a bit of a bitch to setup and I'm not particularly enjoying how dangerous it feels for my eyes (I have reputable laser Goggles etc, but I used to work with similar lasers in an optics lab so know how evil these things can be), and it's quite fumey too. That and the fire risk.

Having said that though, very happy with the results so far. Here was my first ever time running Gcode on the laser (UCCNC seems relatively capable, although clearly not designed with lasers in mind - there is a recent lightburn import plugin which is really helpful). Flipped the axis for the next cut and it looks fantastic - although in my first material test squares I ended up blasting through the 3mm ply and then on all the way through 20mm of MDF.... Whoops.

The below test text is about 50mm wide, took about a minute with a single pass at 3000mm/min 50% power.

Hopefully some point I'll do a summary post with a few complete projects, and more on the 4th Axis testing I've also been up to.





Anyhow, Happy New Year all!

[AndyUK]

Another little project:





4 Twist Umbilic Torus. What's cool is it only has one face.

First project with openSCAD programming to generate the shape, which also allows all the variations to be generated (like different widths, radii, number of twists etc)

[Nickhofen]

It is very beautiful.
Can you please share more information about the dimensions, the way you hold down the wood on the cnc bed, the cutting bits ,how you turn it and align it etc...

[AndyUK]

It is very beautiful.
Can you please share more information about the dimensions, the way you hold down the wood on the cnc bed, the cutting bits ,how you turn it and align it etc...

Sure.

It's 130x130x36mm, two sided machining operation with an 8mm endmill to rough, 4mm ballnose to finish. Ideally I'd have used a long tapered ball nose but didn't have one to hand, so had some silly stickout on a standard ballnose for clearancs. Held down with 3D tabs. Alignment with brass pins - you cut pockets for them on the first side, then the matching pattern into the spoil board. Ugly in progress photo attached.

[needleworks]

Wow, that's an impressive looking piece mate !! I don't suppose you would be able to share the drawings/cutting files ? I'd like to have a shot at that.