BRAZING: alloys & fluxes.

[Eric Estlund]

to build a bike with "micro" fillets?

This may be a thread jack/ drift, go ahead and redirect me if it is. I'm always interested when "micro" comes up. Given the relative benefits (and difficulties) of fillets, I often wonder why the "micro" builders don't pursue TIG, which seems to deal with the super small joinery in a manner better suited to the alloys involved.

Note that I haven't used Fillet Pro, the base of your question, and my observations are mostly in reference to silver and brass fillets/ tinning.

Damn it- more pictures, less typing.... ummmm.... here we go: medium fillet on the front, "micro's" on the back.

[Freddy]

Here is a place to start and get it off Steve Garro's portion, this forum must be overloading, it takes a full minute for a page to open down here on my very fast system?

Anyway here is and internal to some comments and pictures
http://www.velocipedesalon.com/forum...pro-14695.html

[Dave Porter]

You really did this? You mig tacked a tube in place before brazing it? You're putting me on, right?

See page 43 Columbus Cat 2006 "MIG: OK Autrod 13.12" Why on god's green earth would I put anyone on?
dp

[Freddy]

This may be a thread jack/ drift, go ahead and redirect me if it is. I'm always interested when "micro" comes up. Given the relative benefits (and difficulties) of fillets, I often wonder why the "micro" builders don't pursue TIG, which seems to deal with the super small joinery in a manner better suited to the alloys involved.

Note that I haven't used Fillet Pro, the base of your question, and my observations are mostly in reference to silver and brass fillets/ tinning.

Damn it- more pictures, less typing.... ummmm.... here we go: medium fillet on the front, "micro's" on the back.

First is to define a Micro Fillet or internal fillet and it seems everyone refers to something as a Micro Fillet ?
Small 3/16 radius fillets have been raced over the span of my lifetime and I did a lot of them very small with common brass in years gone by with bikes that were made for competition so I know large fillets are more of a long term style than a must.
A recent discussion I was having with another joining engineer brought up a comment, "Why do they think those big fillets are strong, they need to flow inside as well"
Since Dave Porter and I hooked up which is well after he had been silver building with others products, not mine, his fillets are very small and have held up just fine.
But his style was also successful for many years using other products, the wierd break out was never repeated and had never happened before?
That tube is a candidate for electron inspection, it should not have done that.
Eric your work above looks exactly the same as my most common practices from forty years ago, it is just fine? I want to answer any questions that remain if you have them?
History comments about invisable fillets? yes I did make many of them on race bikes with the majority of the filler inside, and so did many other builders before me and after.
It is easy enough to do but what is the point.
All tig joints suffer some degradation just like brazed can, the object is things go better with experience and care and knowing your alloys properties.
An improper Tig joint can be as much as 40% degraded from pre-joined specs if it is done wrong.
Brass, common brass almost never results in that much, more like 10% or less as a rule of thumb, Silver if done with proper tech is most often Zero.
You choose, they all work well enough to make a solid bicycle, always have.
It all boils down to what you find most comfortable to work with, my overseas builders like "Enigma" use all kinds of build methods from Tig to the silver bearing bronze fillet pro.
They all work.
If I was making lightweight bikes, the method would be just the same as Dave Porter uses, very modest fillets with a good secure inner fillet and keep the bike as light as possible.
Dave has enjoyed records broken that held for years on his builds which is a pretty good indication something went right?

[Dave Porter]

Marten did make in interesting observation out using a MIG to tack a tube in place (BTW-how many of you using non supported odd ball shaped tubes wished for a quick and reliable way to locate a tube or bit?) about the relative speed of spot tack cooling. That is certainly true, compared to using gas and to an extent TIG. But, as Freddy, pointed out many months ago, the tube that failed was the down tube, the tube that was tacked was the seat tube...
Steve Garro wanted pix of failed tubes, I sent and erred in even suggesting that it was the fault of a MIG tack since I originally had the tack location wrong. (It gets worse with age).
I think I corrected it then and don't need to spend my time rebutting lame pronouncements..
BTW, Freddy says it better than usual above, Thanks Mr. Parr
dp

[jerk]

See page 43 Columbus Cat 2006 "MIG: OK Autrod 13.12" Why on god's green earth would I put anyone on?
dp

dood-
mig welding that shit is the stupidest thing i have ever read on this forum, and given that i'm a contributor here that's a lot of stupid material.... this is a colombus life tube- not the headers on your deuce couple or a piece of rod iron furniture. when columbus says, "mig: ok autorod 13.12" they're providing an ok for a fucking robot in china that's probably using some pulsed spray transfer mode shit....they're not giving you an ok to mig tack a .4 thick tube!

[edoz]

I worked in a shop that built headers that had 1" x.020" Inconel tubes welded into a large disc of (iirc) 316 stainless. They had guys MIGing them by hand, with no burn through and holding very tight tolerances with respect to the distortion of the tube that stuck out. If a guy knew what he was doing, he could MIG a Life frame, paint it and no one would ever know the difference.

[Dave Porter]

No, DUDE, (correct spelling) the stupidest thing on this forum appears to be you. The MIG'd tube is NOT the one that failed.
Tell you what I'll do pretty soon, I'll MIG an entire Spirit frame and submit for testing... I have no clue as to why this attack on my bike.
You're welcome to an opinion, but near as I can tell from here, that's all you have. And as a moderator you ought to clean up your language.
Just saying.

[jerk]

No, DUDE, (correct spelling) the stupidest thing on this forum appears to be you. The MIG'd tube is NOT the one that failed.
Tell you what I'll do pretty soon, I'll MIG an entire Spirit frame and submit for testing... I have no clue as to why this attack on my bike.
You're welcome to an opinion, but near as I can tell from here, that's all you have. And as a moderator you ought to clean up your language.
Just saying.

i don't care where or why the frame failed. i was commenting on the lunacy of using a mig welder to tack a frame and responding to your citation of the columbus catalog. now you're going to mig weld a whole one? for every million reasons why this is a bad idea can you come up with one good one for doing this? thinking its a bad idea may be an opinion, but it is a far more reasonable and well thought out one than the opinion that it's a good idea to mig weld a bike frame.

[Freddy]

Golly ?
I take two days off from other important projects and check in and what do I find? A War Zone.
I am out measuring soffits and I am tired of climbing the ladder and more hostile distracted posts? Is there a luner cycle right now?

Dave don't bother to Mig a frame up, thinner stuff than those tubes gets migged in production in the real world.
I just don't like the process and am set in my ways.

I think a lot of readers go to the lists and the more confused the posts get make for a tidal effect all made up of negatives, Hell I am gun shy about even making a joke anymore?

Since I am no longer involved with the money end of trying to score cool stuff - Frankly looking at these lists and "Peer oriented shows" is making less sense to this old man.
Get out and score some customers and build away, Omar does, and he seems quite happy.

I want one of your Santa Fe rigs and I will make you such a deal off list.

PS don't call me Mr. Parr that is shameful I am a happy clown and refuse to grow up

[Dave Porter]

i don't care where or why the frame failed. i was commenting on the lunacy of using a mig welder to tack a frame and responding to your citation of the columbus catalog. now you're going to mig weld a whole one? for every million reasons why this is a bad idea can you come up with one good one for doing this? thinking its a bad idea may be an opinion, but it is a far more reasonable and well thought out one than the opinion that it's a good idea to mig weld a bike frame.

Last from me...
You do seem to care else you wouldn't comment.
Here's the deal, I started nearly 40 years ago with lugs and brass, as the years and materials and techniques changed, I changed with them. Before using any new product I do what is known as research and experimentation (R&D). In the case of the Spirit multi-shape the importer's tech dept. assured me that fine grain doped Niobium was more than up to the task of brass temps and as I recall was further stabilized by the welding process. This was also reinforced by the MANUFACTURER who probably knows better than anyone and does not "comment" in their literature without checking with the legal dept. first.
Now you can wax as eloquently or as vociferously as you feel about my lunacy, but I'm not about to change my way of building frames because someone who can't take the time to learn more or experiment thinks that I'm the one with a problem.
As an aside, there are some really talented builders on this list, some only hobbyists at that. I certainly don't make any claims to know it all and I am on the various lists to learn from others, but I never take their word as gospel until it works for me too.
Have a good evening.

[CyclesNoir]

WOW!!!!

This is out of control.

There's a lot of good content in this thread - too bad its getting weighed down with unnecessary attacks.

It's cool that folks can be casual here, let their hair down, and tell it like it is. Sometimes, there is a need to backup some and make sure that the tone and language are appropriate considering the relationship that does or doesn't exist between the parties at hand.

I've never met either Dave nor Jerk face to face. I know lots of folks have a great deal of respect here for Jerk's knowledge as a bike fitter, bike designer, retail bike guru. His posts on these topics stand up to that reputation. He may also have deep tech quals as a fabricator, although that's less clear to me.

Dave has not only been building custom frames for a long time, he has explored areas of framebuilding that go beyond what most big brands accomplish. For example, his work in conjunction with Sandia Labs to create aerodynamic TT bikes (made of steel, BTW). Most of the so called Aero bikes are bunkum (fortunately this situation is gradually improving). Dave's Aero bikes were based on solid science. Ask to see one of his forks with internal chokes. He's the real deal. Look at the fab skills required to build those chokes in a fully functional and durable fork - its not a cakewalk.

ATMO, there is no excuse for anyone calling Dave, or his work, and any of his design decisions stupid. Further, I think it should be rare that this sort of language should be used in this sort of context with any of the builders here, regardless of any pre-existing relationship anyone has with them. Choosing to be unnecessarily critical is a sure way to convince framebuilders to stay away from Velocipede Salon. It will also tend to reinforce the idea of in-crowd and out-crowd rules.

Jerk, you've been a bit sensitive about framebuilders not recognizing your frame fabrication skills, even though its not clear how they could be aware you have any. Ya can't be thin skinned and heartless at the same time. It's just plain bad karma.

Dave, I feel your pain. And I know, that you know, that calling Jerk stupid hasn't moved the conversation to a higher plane.

The insulting comments (from a variety sources over the course of this thread) serve no one any good. The make the Salon appear to be less than what it is. They make their authors look bad.

It's easy to understand emotion under fire and to understand what it feels like to be dissed. Sometimes we say something in the heat of battle.

Comments on a list/blog/forum have a way of being a gift that keeps on giving. They become a permanant stain on the forum and the author.

Personally, I think the rude comments should be editted out by their owners (partly out of courtesy, partly in self-interest). But anyone who doesn't chose this path, gets to live with their own legacy - which is probably a harder mistress than my feeble opinions.

'nuff said.

[e-RICHIE]

They make the Salon appear to be less than what it is.

i was too busy watching jerseylicous and having ice cream to follow this.
we need a time out here atmo.

[jerk]

i have no doubt that dave can mig weld a frame that will not fail. i have no doubt that dave is an exceptional craftsman and has worlds of experience. i have seen his bikes. i just don't get why you would use that joining process on a modern steel tubeset. there are better ways to do it- i am sure dave's skillset allows him to accomplish it without potential failure- i never said it caused the failure of a frame- i just think it's really stupid to tack a frame with a mig welder. it just ain't a process i feel is conducive for the materials. i think it's stupid. lot's of things i do other people think are stupid- doesn't make me any less right though!

sorry for the flame war. it wasn't personal. it was calling the use of a process stupid....not a person stupid or a skillset lacking.