Thursday, August 9, 2012

Quick update now before I go to bed: the red bits are now on Patches - assembly by mallet is so satisfying! - and I had to redo the Y bed to centralise the drive shaft more. There is also one more 608 to further constrain the left-hand Y rail. The right hand one remains relatively lightly guided.

I've got the switches mechanically located and functioning, though the Y bed motor bracket needs a protrusion on it to strategically poke the switch with. I just free-welded some PLA into place by hand and I'll update the files later.

If I run in to an unsolvable problem with even-sided drive on the bed, I can simply duplicate the Z axis drive components and run two drive rods. It's tempting but I want to go really minimal for this build.

The mounting bracket for the stepper drivers needs designing, but that'll be an integral component of the Arduino mounting backboard. There will also be a patch-pad holder for discrete components. This one is designed not to have a custom PCB, and to be ultra accessible. Replacing or substituting components will be a relatively simple process with no soldering. I hope.

Vik :v)

Sunday, July 15, 2012

Patches Sees Red

I'm printing in our nice, new batch of Cherry Red, so Patches is in for another colour change. For the moment, the red bits are sitting there pending a teardown. Note that the new X bearings are far more accessible and I've added malleting points to protect the bearing holders.

Those purple corners are due for a redesign. They need to be able to screw to a baseboard (skips all 4 metal rods at the bottom if you do that, but needs 8 screws) and I am planning on mounting the Arduino Mega clone (NZ$65 from yours truly:) on the one in the left of the photo.

There are a few minor fixes that I won't bother re-printing, but not much so I hope to be able to release the files for public ridicule next week.

Oh, the Z motor tested successfully! Now on to the Y. I might need to redo the edges of the bevel gears but I think I'll get away with it for now.

Excluding gears (10) and the extruder there are 14 printed parts to the Simpleton design.

Oh blast! Forgot to add the cavity for the Y limit switch!

Sunday, July 8, 2012

It's just a matter of firmware...

The "Simpleton" RepRap design continues apace. Now I have the snap-on X carriage figured out and enough pieces in place to wire up the electronics. A few things to sort out still: Some access to nuts is too tricky, the bed corners bump into the endstops a bit early as does the Z axis, the Y captive nut is wrong, and the access to the X drive rod bearings is going to need to be redone.

Still, as it sits on the bench it does a 210mmx190mmx170mm build envelope and weighs 3.6kg, so I haven't lost too much space or gained much weight. Time to start the finer details like built-in cable management and proper endstop holders.

Quite proud of the little CNC-mill-like handles to manually adjust X & Y :)

Tuesday, June 26, 2012

Simpleton Dimensions

Okay, first data points on the Simpleton design:

200mm x 200mm x 200mm working volume, give or take.
400mm x 400mm desk footprint, but does want to drop over the edge a bit.

Tests with an electric drill, while frankly terrifying, confirmed that things will rotate in a stable manner at speed. I'm only expecting to see 20mm/s out of this, which is nigh on 1,000RPM for the M8 shaft, though only about 300RPM for the actual stepper motor. For comparison, a Mendel X axis is typically doing about 100RPM.

This all dictates that I'm going to need an Arduino Mega to flip the steps fast enough, and that  I'll not be doing much in the way of micro-stepping. This is cool: It raises the possibility of cheap and simple stepper motor drivers for those building "in the wild."

No pictures today as the thing is in bits: I'm replacing the Z motor corner. The only screws involved are the ones that screw in to the Z motor itself. The rest is done by mallet. Hammerrrrrrr!

Sunday, June 10, 2012

"Patches" is born

So the Simpleton design is progressing. Suz named it "Patches" after the wide variety of colours that seem to have become integrated with it.

In short, it's all coming together. The lower bearings for the Z drive screws are out of position by 10mm and the platform still raises and lowers smoothly, which bodes well for when I get it right.

The bearing brackets on the transverse drive shaft are  a bit flimsy, the wall that the Z motor is mounted on has an unwanted beam in it, and the motor that slides the deposition bed back and forth is about 20mm too low. A few more parts can be integrated and fasteners removed when I get the positioning finalised. No show stoppers though.

In about a month there should be some design files worth sharing with the world.

Tuesday, June 5, 2012

Back to R&D, phew!

Finally got to spend some more time working on my new RepRap design, so I guess I owe people a picture. We've been busy reorganising our business, looking for new premises, increasing our production volumes of PLA at Diamond Age Solutions and developing new stock. Anyhow, thanks to Her Majesty giving me an extra day off, The Simpleton design is now back on track.

As you can see, I'm opting for bevel gears to drive a cantilevered Z axis that in turn supports a cantilevered Y bed. The smooth tubing is all extruded aluminium, and both Z and Y axes have 608 bearings. Nothing is yet in its final place, and I still haven't designed the actual Y bed, but this baby is going to turn heads when she's done.

Yes I am using rather a lot of threaded rod still - it's the material for the job and because of the cantilevering I actually want a bit of weight in places. But there are a lot of places where the lighter aluminium tube can be used, and a few where it can be replaced with lengths of bamboo or whatever you have handy!

Thursday, January 12, 2012

New Filament Shelving

I built some shelves from my most despised construction material: MDF. The plan was designed to produce the shelving unit from a single 2440x1220mm sheet and seems to hold together OK with panel pins and PVA. I'll need at least another two shelving units to hold the rest of the PLA and ABS stock though.

The plan is to put webcams on the shelving and then people can see exactly what Diamond Age Solutions Ltd. has in stock at any time. So can I, which makes re-ordering easy.

If anyone wants a copy of the plans, pipe up.