Framebuilders - Dropouts for first timer
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This is more of a follow up to a previous post of mine where I asked why using vertical dropouts was recommended for the first time builder. It turns out the only person who recommends them is Chimonas.
What's still unclear is which dropout should be used by the first time builder. If horizontal is the way to go, is it possible to find ones that are socketed as opposed to plugged? It seems to me that socketed would be easier to braze, not to mention fit to standard sized stays. Any advice would be appreciated.
Do you have an oxy-fuel torch, or are you trying to do this with an air-fuel torch?
Andrew R Stewart
02-13-12, 11:10 PM
The brazing process for a socket drop out might be slightly easier then a tabbed one (with a ring insert you only have to heat till flow out happens). But the actual brazing is only one aspect and not the most important one in making a frame most times. The alignment of the dropouts is much more the challenge. Specificly the same lengths for the chain and seat stays. it seems easy to think that making the stays the same length is "no big deal" but many will dissagree. So using a design that has an allowence for the stays being a touch off is the "easier" one for a newbie. (The same goes for tube wall thicknesses and other design aspects...). With traditional (or track if no deraillures) drops the slot is mostly horizontal and makes the chain stay length accuracy less critical. With a tabbed style drop/stay junction one can slide the tab further or less in the seat stay to make up that plane of difference. Of course this is after the other tab/stay junction has been done and the remaining stay's slot is cut purposely a bit deeper the the first, allowing for the adjusting of length. Even with "pro" jigs the rear wheel alignment is, perhaps, the hardest to get right. Lot's of experience with your tools and methods helps make this much more predictible. But that's not who you are yet... Vertical drops remove the range of fudging where the axle sits, without doing a bunch of filing of the dropout. Not a deal breaker but a sign of sloppy craftmanship. Really if you can't do an acceptible brazing of a tabbed drop out then I will question your other brazing on the rest of the frame. Are you practicing? With bronze? Or are you buying into Silver's myth? Learn bronze first is my recommendation. Andy.
I doubt he's doing anything with bronze and MAPP air.
The brazing process for a socket drop out might be slightly easier then a tabbed one (with a ring insert you only have to heat till flow out happens).
I get the feeling he's not even looking at regular tabbed/plate dropouts, just external socket ala Dazza's stuff vs internal like Henry James.
02-14-12, 01:16 PM
Verticals are the way to go if the gearing is to be Indexed..
as axle to derailleur relationship stays the same ,
before and after the puncture repair.
Andrew R Stewart
02-15-12, 09:32 AM
Having done this building thing for so long I find it interesting how the "standard" references have shifted. Back in the day you had (or all you could get from Proteus were) drop outs and track ends. Both were slotted for axle positioning (although only the track drops were actually horizontal). Now, it seems, just saying drop outs means verticals and horizontals refers to what I think of track drops. And if you say "drop outs" that means a cast design with a socket (or plug) to house the stay. I have seen this lack of detail to what a poster is really asking about. Not that this is all that big a deal. Just an observation. With the written word it is so easy to assume one thing when the poster is really asking about another style.
There are reasons that pros and manufactures use cast lugs and socketed/plugged drops. Making the frame easier to build is not why, as much as making it faster to finish and have it stand out in the market place (just look at Richard Sach's stuff as example). Newbies will find it easier to use fittings (and tubes) that have more range of options and aligning range. Andy.
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