...I thought this:
"Design" and "fabrication" are not nearly as discrete as they are made to seem in college courses.
In real life, a design changes while a thing is being fabricated, and a good design is in turn based on fabrication experience.
Even tiny changes can affect materials in ways that can make a big difference. Sixty-eight degrees Fahrenheit is the universal standard for mechanical drawings. That is, a part should have the specified dimensions when it's at 68°. But most shops are closer to 72°, so the actual part will be slightly larger than the drawn one even when it's at room temperature. Then there's wood, which is also subject to temperature changes, and is affected by humidity as well.
So an effective design must take into account these kinds of intricacies, while integrating the perspective of the person doing the fabricating. A good example of how NOT to do this is to educate designers in all kinds of theoretical stress/strain analysis, but deprive them of hands-on fabrication experience.
Fabrication must take into account the intricacies of design, including the intended purpose and the necessary tolerances. Design must likewise take into account the intricacies of fabrication, first and foremost "What is it possible to make?", but also including "What design will allow the part to be made fastest?".
Isolating design from fabrication is akin to isolating thinking from speaking. Your thoughts change depending on what has already been said in a conversation. Your choice of your next words in turn depends on what thoughts have occurred to you. The two processes are happening essentially simultaneously; it's silly to try and ignore one or the other.
These blurry lines are the reason I cannot offer a one- or two-word answer to the oft-repeated question, "What are you studying?".
I'm studying all of this, both designing and fabbing. In part I'm still trying to figure out where the boundaries are: What is possible with today's technology? What is possible with just these three tools, one of which is dull?
And then there's: What's it sound like when an end mill is dull or bent? How do I choose a space in which to set up a shop? What kinds of lighting are best for this kind of work? What type of respirator should I use? How do I draw a part so someone else will understand how to make it on the other side of the world?
Brazing mentioned in an Oscar-winning film
from No Country for Old Men:
Carson Wells: [Wells sits back and studies Moss] What do you do?
Llewelyn Moss: I'm retired.
Carson Wells: What did you do?
Llewelyn Moss: Welder.
Carson Wells: Acetylene? Mig? Tig?
Llewelyn Moss: Any of it. If it can be welded I can weld it.
Carson Wells: Cast iron?
Llewelyn Moss: Yeah.
Carson Wells: I don't mean braze.
Llewelyn Moss: I didn't say braze.
Carson Wells: Pot metal?
Llewelyn Moss: [annoyed] What did I say?
Carson Wells: [Wells sits back and studies Moss] What do you do?
Llewelyn Moss: I'm retired.
Carson Wells: What did you do?
Llewelyn Moss: Welder.
Carson Wells: Acetylene? Mig? Tig?
Llewelyn Moss: Any of it. If it can be welded I can weld it.
Carson Wells: Cast iron?
Llewelyn Moss: Yeah.
Carson Wells: I don't mean braze.
Llewelyn Moss: I didn't say braze.
Carson Wells: Pot metal?
Llewelyn Moss: [annoyed] What did I say?
Bought a crank puller the other day
...so I figured I pop the cranks of the bike I've been riding and commuting on for most of three years. It's an 05 Bianchi San José with the stock cartridge BB.
The cranks were a giant pain to remove...took a cheater bar and a lot of yanking. Finally got them off and discovered that the BB is absolutely shot. Like it's difficult to move the spindle, and when it does move it's crunchy and indexed like hell.
The retaining cup (the plastic thingy in the non-drive-side) took a lot more yanking but also finally came loose. Then I attacked the BB cartridge itself, then with a cheater bar on the ratchet handle.
Flummoxed, I decided to soak the BB in anything I had on hand that was close to penetrating oil: hot sauce (saw it recommended on the BOB list), chain lube, and frame saver. I figure I can't damage the BB any further, and all this stuff should be pretty harmless to the steel frame.
--
Well, that saucy mixture didn't do much to loosen the BB, so I strapped the frame to my back and let the local bike shop take care of it. They didn't even charge me, and the guy who fixed it admired my newly-built-up Peugeot, which was on its maiden voyage.
Today I went out and got some Liquid Wrench for next time. Thanks, Cory.
The cranks were a giant pain to remove...took a cheater bar and a lot of yanking. Finally got them off and discovered that the BB is absolutely shot. Like it's difficult to move the spindle, and when it does move it's crunchy and indexed like hell.
The retaining cup (the plastic thingy in the non-drive-side) took a lot more yanking but also finally came loose. Then I attacked the BB cartridge itself, then with a cheater bar on the ratchet handle.
Flummoxed, I decided to soak the BB in anything I had on hand that was close to penetrating oil: hot sauce (saw it recommended on the BOB list), chain lube, and frame saver. I figure I can't damage the BB any further, and all this stuff should be pretty harmless to the steel frame.
--
Well, that saucy mixture didn't do much to loosen the BB, so I strapped the frame to my back and let the local bike shop take care of it. They didn't even charge me, and the guy who fixed it admired my newly-built-up Peugeot, which was on its maiden voyage.
Today I went out and got some Liquid Wrench for next time. Thanks, Cory.
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