Monday, January 14, 2008

gettin' it straight.

got it going on on keri's bike today, i was going to do all this yesterday, but i went out and stared at the project, and it all just didn't add up, so i went back in the house, layed on the couch, and went to sleep. i guess i've just been really gettin' on it lately, and i guess it all caught up and i needed to listen to my head/body and rest. it's been a busy month, and i've got three bikes at paint and one in the jig right now. whew. gotta get ready to go to portland, too, but denise's show bike is done, and gillis's is getting sent back from paint tomorrow, and john w.'s bike will follow it by a few days......sooooo, i tried to get a little picture show of my work on keri's bike that i did today, i hope i get the picture sequence correct and that it sorta makes sense. with frameforum down, maybe i can help a little in framebuilding tutorial...i started out this morning with the front triangle all tacked up. the frame jig only holds the tubes in the desired geometry so you can put "tacks", Little blobs of metal meant to affix everything together all tight. plus, i hand finish all my miters after the mill copes the fish mouths to the desired angle and length, and to the correct intersecting tube diameter. then, i align the triangle to damn near perfect straightness on the bringheli table. then, back to the jig it goes. now i bolt the rear dropouts into the anvil chainstay fixture. it holds everything straight while i braze in the dropouts {in this case, stainless steel paragon slider lites.} i use the fixture, a machinist square, and a sharpie to draw in the slots, then do a pretty accurate cut with a fine tooth hacksaw blade and framebuilder's eye. then, i perfect the slots with a thin warding file to a tight fit and bevel the ends with a 14" bastard file and round those off with a 10" rattail file and clean the insides with an aluminum oxide bit so the silver alloy will bond the stainless steel to the regular steel. some flux, some well trained heat, and some hot soapy water and then they go back into the fixture to be both mitered at the same time. then, i perfect the fit to the bottom bracket shell and tack the stays to the shell. once cool, the entire frame assembly goes back to the alignment table, gets all straightened out, then back to the jig. now, the chainstay brace gets handcut from a cromoly strip and brazed into place between the chainstays, and the entire alignment sequence is repeated including checking that the dropouts are square to each other and that the wheel fits into the dropouts straight and with correct clearances, and that there is sufficient clearance for the crankarms and chainrings...... and, here is the frame as she sits tonight, lookin' good! seems like alot of steps, but it's alot easier then seatstays, which i have to completely fabricate and bend from scratch - those are tomorrow! see you then, steve. EDIT: i didn't manage to get the pics in totally correct sequence, but hopefully you get my drift! steve.


Anonymous said...

I think you're overthinking the entire process's JUST a bike!


Preskit Matt

steve garro said...

......then i take it you're hunky-dory with me skipping all that time consuming alignment stuff on your upcoming build then? steve.

Sabrosa Cycles said...

steve - do you always slot the stays to match the dropout? I slot my stays along the center line and cold set the drop out to match the stays. I have yet to do a set of sliders, maybe the coldset option doesn't work so well with the sliders?? dunno.

Anonymous said...

Didn't you see my HEHE? You do great stuff with steel my friend!


steve garro said...

yep, i sure do. it's harder to do, but so is everything i do in my process, i think.......i'd hate to have to bend the standard sliders, they are THICK. heck, all of paragon's cnc-machined dropouts are pretty resistant to bending, but, that's why i use em', i guess! i'm not much of a fan of cast dropouts, although i'll use a high-quality socket now and then, like when someone wants double rack/fender eyelets. i {personally} don't like the "breezer" or "wright" style dropouts, i just know that a slotted machined dropout is just gonna last, and that makes me feel good, even though it costs me 3x as muck and takes 3x as long, but that's my style......steve.