AndyUK's Build - 1.2x1.0m Gantry

[Kitwn]

Thanks Kitwn, really helpful link! :)

Yep - got it in one, I suspected anyone into their wooden clocks would know.

I love some of the designs on that site, especially the ones that use the wood as a spring to snap pieces together. They do test the accuracy of your machine though, I copied one idea which made a joint that had the pieces fit rather like the pieces of a jigsaw. Except they didn't. That was the inspiration for the latest round of upgrades which I'm hoping will significantly improve the accuracy of my machine. The Z axis is now made of aluminium instead of plywood so I'm cautiously optimistic!

I consider wooden clocks to be a form of 'kinetic sculpture' just like Mr Roy's creations. Problem is I (unlike everyone else it seems) insist that a clock, any clock, should tell the right time. Hence my current (stalled for want of a working router) project for a GPS-locked wooden pendulum clock.

[AndyUK]

Good to see you are getting some time at least and some real life creations Andy! I think I need to use mine for every birthday/xmas present for the next 10 years to recoup the cost:)
What method did you use to tram the spindle?
Interested in the coolant mister too for the future - don't think I saw that in your build log?
Ryan

Haha - yeah. I've already gotten a couple of those ticked off...!

The mister is a £5 jobbie off ebay - nothing special to it, just the generic Chinese one you'll find. Voicecoil has made me a new nozzle for it to open up the flow - he discussed the modification in one of his threads; I'll post a picture when I next use it.

Spindle tramming - I used a dial gauge in the spindle, rotating it around on a surface place that is already setup to be planar to the Y and X axis. I have a tramming gauge which I would have preferred to use, but its with the mill locked down a few hundred miles up north.

I love some of the designs on that site, especially the ones that use the wood as a spring to snap pieces together. They do test the accuracy of your machine though, I copied one idea which made a joint that had the pieces fit rather like the pieces of a jigsaw. Except they didn't. That was the inspiration for the latest round of upgrades which I'm hoping will significantly improve the accuracy of my machine. The Z axis is now made of aluminium instead of plywood so I'm cautiously optimistic!

I consider wooden clocks to be a form of 'kinetic sculpture' just like Mr Roy's creations. Problem is I (unlike everyone else it seems) insist that a clock, any clock, should tell the right time. Hence my current (stalled for want of a working router) project for a GPS-locked wooden pendulum clock.

Haha - I set the router up for a 16mm diameter hole, along with a series of already prepared GCode files for +/- 0.1mm offsets to try and fit the first bearing in. I can't tell you how happy I was when the 0 offset file measured 16.00 on the digital calipers, and the bearing was a tight push fit first time. Bliss.

I suspect I'll end up trying to make a few of his designs... they're definitely in the amazing artwork category. GPS locking them however - that's another level!


Couple more projects - My Brother wanted a 'Plumshed' sign (don't ask - long story), so I did a V Carve with some google fonts. Really love how much the black paint adds.



Also spent some time trying to improve my 3D CAD skills - mocked up a Sopwith Camel prop, and tried a 3D carve. The router did an amazing job (its about 600mm wide) - I really love how smooth and flowing the contour is after a single finishing pass with a 6mm ballnose. The only issue I had was that I messed up the CAM and only got half the model (oops). Before this cut I was slightly worried about if my Z axis was okay - one of the earlier 3D carves had some suspected lost steps - but it handled this one perfectly. Cooling is definitely a need-to-fix item on my agenda though - that little pump just can't cope with the length of cooling loop I've got, and after about an hour the lower section of the spindle was hot (still comfortable to touch, but I'm guessing it shouldn't build up heat if the cooling is working well).

[Kitwn]

Nice work!
On the cooling front I found that larger diameter piping (8mm instead of 5mm I think) doubled the flow rate from the same pump. Short restrictions such as the inch-long pieces that connect to the spindle itself made no difference but it sure made a difference over the main several metres.

I built a prototype GPS clock last year, link below. The GPS receiver is the little blue circuit board that appears about 26 seconds in. The pendulum is oscillating freely at it's natural frequency, driven by an electromagnet, but is still forced to run in perfect sync with the one pulse per second (1PPS) signal from the receiver.

[AndyUK]

I really like the joining of precise timing and electronics with wooden clock - fantastic!

Heres how the prop turned out, after a few duds and a bit more learning. Nothing special, but I'm rather pleased with my first two-sided 3D carve - quite hard to photograph that twisting shape though..




Right - lets get back to building machines shall we? Its become rather apparent that dust collection is essential. I'm thinking I'll print one of Boyan's turbo shoes, but has anyone got any dust collection system recommendations? I'd like to be in the garage while its on, so thats a consideration.

[Kitwn]

Andy,
That prop looks great. I love the way the grain flows along the blades.

I do take a certain pleasure in the idea of a wooden pendulum clock being the most accurate timekeeper you can own. The mixing of technologies is fun, though some of the purist mechanical clock builders are not convinced.

[Nickhofen]

The grains that run the whole length of the propeller was the first thing I notice too, on purpose cutted from the piece of wood for more strength? Maybe a working propeller?
Andy did you hand sanded after the finish passes?
Is the propeller balanced? I mean did you try to spin it and see if it is?

[AndyUK]

The grain is deliberately running the length, yes. I did try a miniature one (10cm rather than 40cm) with the grain running in the opposite direction, but it snapped during the bottom side roughing.

I believe that's how real ones are supposed to be done for strength during use? But I have no intention of using this in anger - although it's quite tempting! This one is purely "because I can" and it was a challenge for my CAD, CAM and CNC experience!

Yes, hand sanded to remove tabs and clean up a bit, but the shaping is all through a 6mm ballnose. Obviously the photo is just a roughing cut - see the earlier post for what one side looks like after finishing pass. Prop isn't balanced perfectly - but does produce some wind! I should have machined the central shaft with the CNC but didn't want to risk the part at that stage as it's taken a few attempts - each requiring a few hours. It's not too far out though, I think a bit of selective sanding and it would be useable. I have a prop balancer somewhere; I'll stick it on later and see.

[Clive S]

I believe that's how real ones are supposed to be done for strength during use?

I think the real one's (Spitfire etc) are laminated not one piece . You have made a very good job of it

[Nickhofen]

I think spitfire had an aluminum alloy propeller, but yes the old blade of WWI was wood multilayer made.
You usually make two cuts on the wood to his length and then rotate the center beam 180 degrees at his longitudinal axe, for a small scale wooden propeller.
With your cnc you can always make an aluminum one.

[AndyUK]

Promised an update when I ventured into Aluminium; its only the smallest of steps, but I'm pleased with the results.

The "client" has requested a lampwork beadmaking tool which could form the molten glass into a heart shape. This is the first in a series of tests; the eventual product will need to have two identical sides to squish the bead into shape, but we've just started with a single side for now.

Tried two shapes, a 3D heart and a 2D heart. I pocketed and roughed with a 4mm single flute endmill at 18k RPM and 1.5m/min. Kept the DOC very low at 0.5mm as this is my first time, but the router wasn't phased in the slightest. Then finished with a 3mm Diameter ball nose, 24k RPM 1m/min. Very basic tool paths from aspire, nothing fancy. Went a bit overkill and gave it lots of air blasts to clear the ships and plenty of WD40 in between!

To give an idea of scale, these hearts are designed to fit within a 15mm diameter circle. Very small.







My thoughts are slowly turning towards the 4th Axis that I'd like to add to this machine, but I haven't come across any dedicated build threads yet. Anyone got any initial recommendations / suggested reading?