LI-ghtcycle
10 MW
I've been going to UBI (United Bicycle Institute) for about a year's time (not all at once, just a couple weeks here and there) and I will be finishing the entire range of courses once I take the Titanium TIG Welding class for building bicycle frames, but I wanted to share my first "E-Bike" friendly design.
First off, in the bicycle world, generally lighter is better, so I had to buck the system a bit to do the opposite, made something of a "Dirt Jumper" frame with the geometry of my old favorite Trek Steel MTB frame from the early 90's.
Here is the result:
Really like these heavy duty Surly Drop-outs! They are disc ready and about 12MM thick!
I drilled 2 holes on each side for additional "braze on" mounts (water bottle style) which I opted to TIG weld in class as well instead of braze, they came out ok, but a couple of them cratered pretty bad, they will hold ok, but look pretty bad lol!
I will most likely going to just braze the last 4 unless I can get good enough performance out of my neighbor's Harbor Freight TIG welder (it's really hard to get a low end welder to give you the low arc stability needed for welding such thin tube with -out blowing holes) and it looks much nicer with it just silver brazed on, and just as strong as anything in this thin tube that is bicycle tubing will ever be.
I have a really strong and stiff 38 mm Down Tube (same diameter as the BB!
) that I plan to use to my advantage with a BB drive sometime, and I have plans to build something that will accommodate a small diameter hub motor (Mid-Monster or Hub-Monster from John in CR) with the shorter chain stays that I built also in class (this was an accident where I mixed up a part of the full scale drawing in class, and I got to keep the "mistake" Surly Drop-outs just like the ones used in this frame on short chain stays that will be ideal for a 20" wheel w00t! :lol: ) so I should have a nice set-up for a my next frame!
I really like using 4130 Cro-Mo tubing, it's cheap in the straight gauge (most bicycle tubing is butted, or thinner in he middle than the ends to save weight and allow flex) which I plan to use in most of my future frame builds.
I also was really impressed with the equipment we had in class!
Anvil and Arctos brand frame fixtures (jigs) are amazing!
http://mechanicalhacks.wordpress.com/2011/03/31/bike-frame-jig-survey/
Everyone in class was able to easily build a frame with a tolerance of +/- 1 mm, (this is pretty amazing considering half of the class had never built a frame much less welded before, most production frames are in the 2 - 3 mm tolerance range, even the big name companies) and these fixtures are really easy to adjust for different sizes, gonna need to wait till I can figure out a game plan to get the cash for some of the better equipment (Miller TIG Welder, and assorted tools, fixture, etc.) but I can really see the difference in how much better the good stuff welds, and is to use!
First off, in the bicycle world, generally lighter is better, so I had to buck the system a bit to do the opposite, made something of a "Dirt Jumper" frame with the geometry of my old favorite Trek Steel MTB frame from the early 90's.
Here is the result:
Really like these heavy duty Surly Drop-outs! They are disc ready and about 12MM thick!
I drilled 2 holes on each side for additional "braze on" mounts (water bottle style) which I opted to TIG weld in class as well instead of braze, they came out ok, but a couple of them cratered pretty bad, they will hold ok, but look pretty bad lol!
I will most likely going to just braze the last 4 unless I can get good enough performance out of my neighbor's Harbor Freight TIG welder (it's really hard to get a low end welder to give you the low arc stability needed for welding such thin tube with -out blowing holes) and it looks much nicer with it just silver brazed on, and just as strong as anything in this thin tube that is bicycle tubing will ever be.
I have a really strong and stiff 38 mm Down Tube (same diameter as the BB!
) that I plan to use to my advantage with a BB drive sometime, and I have plans to build something that will accommodate a small diameter hub motor (Mid-Monster or Hub-Monster from John in CR) with the shorter chain stays that I built also in class (this was an accident where I mixed up a part of the full scale drawing in class, and I got to keep the "mistake" Surly Drop-outs just like the ones used in this frame on short chain stays that will be ideal for a 20" wheel w00t! :lol: ) so I should have a nice set-up for a my next frame!I really like using 4130 Cro-Mo tubing, it's cheap in the straight gauge (most bicycle tubing is butted, or thinner in he middle than the ends to save weight and allow flex) which I plan to use in most of my future frame builds.
I also was really impressed with the equipment we had in class!
Anvil and Arctos brand frame fixtures (jigs) are amazing!
http://mechanicalhacks.wordpress.com/2011/03/31/bike-frame-jig-survey/
Everyone in class was able to easily build a frame with a tolerance of +/- 1 mm, (this is pretty amazing considering half of the class had never built a frame much less welded before, most production frames are in the 2 - 3 mm tolerance range, even the big name companies) and these fixtures are really easy to adjust for different sizes, gonna need to wait till I can figure out a game plan to get the cash for some of the better equipment (Miller TIG Welder, and assorted tools, fixture, etc.) but I can really see the difference in how much better the good stuff welds, and is to use!
