I did several days in a row with 2-3 miles walked with allergies and now my back is complaining, not loudly, but making its presence known. This is my notice to take a break and not overdo things. Also after several days of good behavior the “m” key on the keyboard is acting cranky again, and Google keeps sending me notices that my OS is no longer supported.
Now this can be dealt with in many ways. I can buy a new computer (ha, ha), I can get the keyboard fixed and install Linux, I can install Linux on my Dad’s old computer after I drag it out of the box it has been stuck in since 2012. And one of my friends might have an old laptop they can give me. First I need to call and find out how much getting the keyboard fixed will cost, then work from there.
On the Sprint-T I have been contemplating a frame revision that would add maybe 40 pounds but provide a major increase in torsional stiffness. It isn’t as pretty now, but it will be much more tunable for handling. Basically what I did was make sure all the possible load paths were continuous and triangulated in all 3 dimensions and clear the body. It was that last requirement that has been the monkey wrench in the works, as the body is 34″ wide underneath and 45″ wide at the top and there has to be a structural member to meet the mounts underneath or the body would have not crashworthiness. That’s not the problem by itself, the problem is the diagonal from the top of the rear roll hoop to the bottom of the front roll hoop. Now I thought I had this solved a while back, but when I traced the load paths I found it went all wonky at the front roll hoop. The loads went from in line to bending around the front hoop because of having to have a member under the body and the diagonal snake around the bowed-out sides because there is no straight line from the top of the rear hoop to the bottom of the rear hoop. Interestingly enough, there is straight line access from the top of the rear hoop to the middle of the front hoop, and back to the bottom of the rear hoop, but that places bending loads on the front hoop unless there is a corresponding member from the front suspension support to the front hoop. And that is what increases the weight so much, about 8 additional members about 50″ long each weigh 30 pounds total plus the gussets at each intersection add about 8-9 ounces each end. If I could reduce the size of the structural members any more without worry about damage from people leaning or climbing on the car I could make it lighter, but I have to use the frame as a ladder to get in through the top of the cage.
While I have been writing about fixing the mistakes in my frame I had a show about engineering mistakes and fixing them on the Science Channel on the Tee Vee. Some of those mistakes cost hundreds of millions of dollars to fix, some couldn’t be fixed for any amount of money. I’m just glad I’m finding my mistakes before I spend money building unusable junk.
Witch on a Bicycle 