Friday, February 18, 2011

Hyper/ We control

If I hadn't been so dog tired and if Jeff's retro Ford F350 had a cd player this is the track I would have blasted out on our drive back from the 'Couve.

Toolpathing: the ninth circle of hell........

Never again will I utter the phrase "something that we can cut quickly & easily on D's awesome CNC machine....". Not because it isn't totally awesome (which it is) but because of the Tron era software required to program the toolpaths. In excess of eight hours were required at the computer to enable four hours of cutting. My hunch is that the designers of this software went on to write the federal tax code or perhaps the terms & conditions of your medical coverage. A more utterly opaque and unintuitive interface would be hard to imagine, however, hours of slow torment paid of big time. Once everything was set D's Multi-Cam fairly tore around our sheet of 6mm Russian birch ply (check the video below). We cut out our proof of concept! High fives all round! Admittedly we had a few do-overs (depth settings seemed to challenge us) and a couple of parts that failed to stick to the particle board and were thus munched by the cutting tool. At one point there was a voltage fluctuation that shut the machine down. We had to unscrew the collet, manually push the gantry back so that Jeff could crawl under the machine with a flashlight & a voltage tester, check and then reset the machine.
But it was all worth just after midnight we beheld a pile of plywood parts representing the sum of our efforts so far. I have to say that my first impression was; 'is that it, did we forget some parts?' and then 'are we seriously going to make a bicycle out of this pile of scraps?' It just seemed so physically insignificant but as we started slotting the parts together the form took shape. The accuracy of the machine is impressive and all the truss frames slid with reassuring firmness into the slots. Obviously our work here has just begun. Next we meet at Jeff's shop for the long process of sanding, assembly, jigging and gluing. Some of the parts, particularly the blocks that house the bottom bracket shell and the head tube, are still to made and we haven't decided yet if we will CNC the dropouts or just cut them by hand. And don't even get me started on the steering. One of the interesting things to discover in the weeks to come will be how light & how stiff? Ideally we have a target weight of 80lbs for the fully assembled bike and currently the dry weight of the frame parts (minus glue and epoxy) is around 14lbs. If it turns out to be excessively 'noodly' then we will have to add material and re-assess how we mitigate lateral flex.

Right now we are the are the happiest wooden cargo bicycle builders this side of the Willamette......


Tuesday, February 15, 2011

CSS_Let's reggae all night

My favourite trash-pop-punk band from Sao Paulo, Brazil

All change..........

A month long hiatus of intense development and deep exploration of process and purpose. The last time we went to the shop we decided to put the fork-less steering system on the back burner as it was clearly proving to be a distraction. The more we delved into it the more we realized that we were heading down a rabbit hole of cause & effect that would end up draining our will and focus. Fork-less steering was a concept, we agreed, that could be more profitably explored further down the road when other more fundamental issues had been resolved. Instead we shifted gears and strategy and brainstormed the fastest way to create an all wood proof of concept. Basically a down & dirty sheet material form that slots together and could be cut quickly & easily on D's awesome Multi-Cam. A long couple of weeks followed at the computer bringing the form to fruition in Solidworks with many stop, starts and revisions in response to Jeff's woody worldlyness.

But a funny thing happened on the way to creating what we always thought of as a stop gap, a stepping stone to Renovo-esque fluidity. As we started to look beyond our proof of concept to model #2 there seemed to be an enormous disconnect between the formal volumes we were envisioning and the functional realities of what we were trying to achieve. I had always imagined that the CNC'd monocoque, fluid, sculptural & organic was were we were headed but the further we dug into it the more the proof of concept started to display an elegance and simplicity that we found compelling. Conversely my sketches that tried to marry the various hard points via the monocoque process became cramped and unconvincing. Clearly I had hit a conceptual wall. As the Dude famously said;"My thinking has been all uptight about this....". Something had to give.

On the night of the Oregon Manifest Launch Party as Jeff and I slowly weaved our way home from the Lizard Lounge via the Springwater Corridor (that HUB organic lager is quite strong!) we discussed the different approaches. Considering what we were building, was the Renovo way the correct one? Was our flat-stock, slot-together idea more suitable? How realistic was it to try and combine both construction techniques?

A couple of days later I sat down at the computer and started model #2 but within an hour I was stuck. Nothing about it produced that 'aha' moment. I deleted the model and started again pretending that I had never set eyes on a Renovo and knew only of 6mm birch ply. It is at moments like these that I want to kick myself because the model came together with such ease and inherent consistency that clearly this was the direction we should have pursued all along. I was gratified when Jeff had the same reaction when I showed him the model that evening. Suddenly it was like the log jam cleared and a torrent of ideas followed. Forkless steering was firmly back on the agenda as was cable steering, an idea I had floated previously but had abandoned through timidity. A bunch of problems we had envisioned evaporated with the new direction and ideas came tumbling out faster than we could sketch them. It was exhilarating!

Of course all of this euphoria will have to surmount the obstacle course of reality but right now we are stoked! So this is what we think it might look like...........