Framebuilders - dropouts

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stanridgespeed
01-15-10, 10:56 PM
http://farm3.static.flickr.com/2788/4278397808_74582c9438_o.jpg
for your viewing pleasure. I fill my vent holes after brazing. (the gold dot on the seat stay)
JohnDThompson
01-16-10, 08:26 PM
Mmm... dropouts!
http://www.os2.dhs.org/~john/fixed-frame/drops.jpg
Live Wire
01-16-10, 09:37 PM
Nice John! Very Zeus....ish.
Here's one from the last fixed gear frame- handcut 4130 and just before ss faces are added.
Aaron_F
01-17-10, 11:13 AM
I fill my vent holes after brazing. (the gold dot on the seat stay)
I that pretty typical on custom frame builds?
Eric Estlund
01-17-10, 01:51 PM
A couple:
133607
133608
Kommisar89
01-18-10, 08:39 PM
Hmmm...just curious...is there any sort of standard for dropouts? Like if I had a frame built today and 20 years from now I damage a dropout and need to have a new one brazed in, does the builder just pic an appropriate dropout and fire up the torch or do I have to go to the future version of eBay looking for a vintage dropout that fits?
unterhausen
01-19-10, 03:42 PM
dropouts have gone through fads and the styles have changed over the years. There is no standard. You might have to replace both dropouts to get a match.
dropouts can be fixed by welding most of the time.
If you were to replace both dropouts and the stays wouldn't line up, a little judicious bending will make things line up. I had to do this with a dropout replacement recently. Some dropouts meant for replacement use have large tabs so that the unused part can be removed. Another alternative is having a matching dropout cut on a water jet.
painthawg
02-16-10, 08:57 PM
for your viewing pleasure. I fill my vent holes after brazing. (the gold dot on the seat stay)
I have been practicing my silver brazing for a lugged frame. Feeling pretty confident. That said, if I am considering cutting out my own plate style dropout like yours, as opposed to a dropout with sockets for the stay tubes, will I need to be able to braze with brass to get the proper strength?
JohnDThompson
02-17-10, 06:29 PM
Hmmm...just curious...is there any sort of standard for dropouts? Like if I had a frame built today and 20 years from now I damage a dropout and need to have a new one brazed in, does the builder just pic an appropriate dropout and fire up the torch or do I have to go to the future version of eBay looking for a vintage dropout that fits?
That depends on how much importance you place on matching the undamaged dropout. As long as the general style (i.e. track, vertical, forward facing, whatever) is the same you can pretty easily come up with a functional match. If you simply must have an exact match to your Campy 1010 "open C" dropout, you may have a problem.
unterhausen
02-20-10, 11:06 AM
I have been practicing my silver brazing for a lugged frame. Feeling pretty confident. That said, if I am considering cutting out my own plate style dropout like yours, as opposed to a dropout with sockets for the stay tubes, will I need to be able to braze with brass to get the proper strength?
you can use a silver that will build a fillet. Or use plugs. Personally, I prefer to use brass most of the time.
painthawg
02-20-10, 07:54 PM
you can use a silver that will build a fillet. Or use plugs. Personally, I prefer to use brass most of the time.
I hadn't thought of a plug. That could very well be the best compromise for my current skill level. I'm excited to hear you offer that up.
Brass will definitely be the next step for developing my skills. I bought brass when I bought my silver but I haven't had a chance or the moxy to give it a try yet. I guess I could start simply with making pools/puddles on flat plate?
edit: Also thank you for your post. The plug idea is excellent input.
rodar y rodar
04-14-10, 11:06 AM
My turn! Here`s my first set of dropouts- finished them last week and I`ve been dying to post `em up for show and tell, but our digital camera bit the dust and I just now borowed one from my brother for some pics. I did a few practice brazes on dummy drops and didn`t like the way I had slotted the stays, so I came back to this thread for a little research and tried again. There are a few little pockets that don`t show up in the pictures, but I think I`m going to wait until the other stays are brazed on and then go back and touch up with silver after all the bronze is done.
The rest of the bike (so far, anyway) is on Photobucket:
http://s161.photobucket.com/albums/t218/brianylupita/Homebrew%20recumbent/
It`s a rough copy of a Rans V-Rex. Since I don`t have a good place to work at home, I`m going in a few hours early to the plant twice a week and knocking out whatever I can. It takes longer that way since it isn`t feasible to do a little bit when I only have an hour or so to spare. On the bright side, I have the whole toy palace at my disposal. Hopefully I`ll scrape together enough dough for another shed this year so I can do my next build (lugged road-sport) at home. This one should start taking on a bike shape by next week and I hope to be riding it around midsummer.
unterhausen
04-14-10, 01:08 PM
I see it's a recumbent, so I don't really understand the design. On a DF, it makes sense to braze on the chainstays first. That way you can join the chainstays to the BB and align the main triangle and the chainstays before brazing on the seat stays. Adding the seat stays couples the alignment of the rear triangle to the front triangle, which is a bad thing if only one of them is off.
this thread has been around for a while now and this is the first time I realized the title was misspelled. So I fixed it.
rodar y rodar
04-14-10, 07:42 PM
Ah- I know that the CSs are generally brazed in first, but wasn`t quite sure why. Thanks for the explanation. Like you noted, this frame is a bit funky, with 12 in. "seat stays" and 37 in. "chain stays". I thought it would be silly to do the long ones first because they would be too wobbly out at the end of that long span. As soon as I stick the short ones to the back of the main tube, it`ll be self supporting and the alignment ought to stay put much better while I prep the long ones.
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