Power, lathes, wings

Reprap prototype PSU is done and ready for the stepper controllers to arrive now. All boxed up nicely. If memory serves, it didn’t have a fan when it was in the fax machine, so should be fine in the enclosure. At worse I might have to drill it some extra air holes.
Mains lamp, some (vintage) terminal posts, switch and IEC C14 socket.

Even took the engraver to the front panel to mark out the various terminals and added a couple of ferrite beads to the lines to be on the safe side, and used some cable wrap to keep the wires tidy.

Today I also finally removed the piston and cam off the old compressor pump, and filed down a pully to fit. I’ve hooked this up to the 3rd party headstock from the Black and Decker extruded aluminium wood lathe I found last year. It’s meant to be run by a type of drill they no longer make, so the compressor motor should be easily powerful enough. Currently getting a head speed of about 3200rpm, so it’s currently about twice as fast as it needs to be. Will see about swapping the headstock pully for something larger (I have one, but getting the old one off will be a pain).
It’s not urgent, but it’s sitting around and there’s a friend who should be able to use it once it’s basically working.
Also made a control box for it, currently a simple latching safety power switch (see background of first image) from a broken garden shredder and an old RS project box. If I find a spare suitably rated rheostat I may add a limited speed controller.

Also the sewing for the set of “Navi” wings was mostly done today, but one of the blue plastic rods snapped while trying to flex it into it’s “pocket”.
After some considerable swearing and therapeutic angle-grinder time (see above compressor pump), I will tomorrow attempt to construct a coupler out of clear perspex rod and use it to join the two broken ends, as the stress on them will likely be more than any other repair would take. this may mean purposefully breaking and repairing the opposite wing to match.

[20/06/2010: Amalgamating old posts from “Dreamwidth Creative Blog” into sci-fi-fox.com to re-purpose DW blog account.]

PSU Wiring

Some progress with inventory today, but got a bit sidelined into working on the old fax machine PSU, which puts out 5v and 24v, and should be powerful enough to run the stepper control circuits.

Boxing it up is fairly important, especially if there’s the chance of metal filings wandering around.

Using an old comms relay box of some sort and making a new front panel out of some aluminium plate from some Dell drive tray blanks.

[20/06/2010: Amalgamating old posts from “Dreamwidth Creative Blog” into sci-fi-fox.com to re-purpose DW blog account.]

Spent most of today creating inventory templates for workshop stock. After unexpectedly running out of materials yesterday, I’ve realised I need to manage it all much more actively.

I also have an order of electronic sundries on their way to me, including some Darlington transistor arrays and stepper-driver ICs. This should be enough to get prototyping of the Bonsai Repstrap to the next stage.
Comparing the price of dedicated driver ICs, I’m wondering if I couldn’t make quite a saving (on cost and part-count) by using a Sanguino rather than direct Paralell-port control.
The Reprap still uses stepper driver ICs as well, but could a Sanguino drive the Darlington array directly? It sounds like it would have enough processing power spare to manage the sequencing.

Anyway, time to see how the castings are doing in the heated cabinet, and get some inventory done.

[20/06/2010: Amalgamating old posts from “Dreamwidth Creative Blog” into sci-fi-fox.com to re-purpose DW blog account.]

Run out of Shore 40. Need to order some more in and write up a proper supplies tally sheet so I don’t get caught short again in future. Only one current order should be affected.

I’m also down to the dregs of the water-clear resin. Will probably only restock on demand for the moment.

Also have created a page for the Bonsai Repstrap on the RepRapWiki; http://objects.reprap.org/wiki/Bonsai_Repstrap

Need to place orders for more shirts for Confuzzled in a months time. Hoping to have one of my own designs included in that order.

[20/06/2010: Amalgamating old posts from “Dreamwidth Creative Blog” into sci-fi-fox.com to re-purpose DW blog account.]

Some progress

I have not been coping well today.

Footpads haven’t bonded correctly. Gluing method hasn’t worked very well. I guess the rubber chemistry changes while setting. Unset won’t bond to set.
Going to have to try slashing the velcro to get rubber to bond into it better.

Still, one set come out acceptable.

More casting tomorrow. May catch up yet.

Also roughed out the folding mechanism for the Bonsai Repstrap..

A portable 3D printer is certainly feasible.

[20/06/2010: Amalgamating old posts from “Dreamwidth Creative Blog” into sci-fi-fox.com to re-purpose DW blog account.]