Fillet brazed and Bi-laminate bikes = Sexy

[exapkib]

One of these days I'll take some better pictures . . .

[gomango]

Originally Posted by rwsaunders

My riding buddy's Bilenky...purchased here from a Formunite and tidied up by yours truly. Absolutely stunning fillets and paint.

Agreed.

I gleefully picked up the other one the seller had and I remain thrilled.

It rides and looks great. imho

[IMG]Untitled by gomango1849, on Flickr[/IMG]

[IMG]Untitled by gomango1849, on Flickr[/IMG]

[buldogge]

Red Star Uno…Fillet brazed S3 goodness...

-Mark in St. Louis

[David Kirk]

I really do enjoy the process of making fillets and then just staring at them. It's never gotten old.

dave

[8aaron8]

I could stare at Kirks fillets for days

[gomango]

Originally Posted by 8aaron8

I could stare at Kirks fillets for days

Agreed.

Beautiful work.

[buldogge]

Add my name to the list...Simply luscious…

Someday!

-Mark

Originally Posted by 8aaron8

I could stare at Kirks fillets for days

Originally Posted by gomango

Agreed.

Beautiful work.

[malcolm]

I'm lucky enough to have two fillet brazed Kirks one I acquired and one made for me. There are many skilled brazers out there that produce beautiful bikes, but Dave somehow gets the proportions and the curve/arc of the fillet just right and produces the most lovely flow of one tube into another. Kudos to Dave for posting his work and participating.

[El Chaba]

Hey....Somebody post some Jack Taylor photos.....No discussion of fillet brazed bikes is complete without the mention of Jack Taylor....

[Lewis Moon]

I'm actually not much of a fan. To me fillets are just a lot of extra metal spackled onto a joint. I'm sure they can be done with minimal brass and probably don't add a lot of weight, but I'm a form follows function guy. I'd rather see pretty welds.

[Black Dog]

Nice work Dave. I know how you feel, being a carpenter there are certain things I love doing and then catch myself staring at the finished product. It is the real reward for working with your hands to build things. That moment of getting lost in the pleasure of looking at the product of your effort.

[David Kirk]

Originally Posted by Black Dog

Nice work Dave. I know how you feel, being a carpenter there are certain things I love doing and then catch myself staring at the finished product. It is the real reward for working with your hands to build things. That moment of getting lost in the pleasure of looking at the product of your effort.

Well put.

dave

[MrDangerPants]

Tomii #12 before paint:

[David Kirk]

Originally Posted by Lewis Moon

I'm actually not much of a fan. To me fillets are just a lot of extra metal spackled onto a joint. I'm sure they can be done with minimal brass and probably don't add a lot of weight, but I'm a form follows function guy. I'd rather see pretty welds.

I don't say this to try to change your mind nor to say you are wrong. If you don't get turned on by fillets I more than respect that.

I suppose the reason I write is to comment on the word "spackled"........it may come as no surprise that I would not chose that term for top shelf fillets. The laying of a tight fillet is every bit as neat and fastidious as laying tig beads and is quite the opposite of what some might think......that a lot of brass is schmeared on with little care and then filed down to look good. A skilled fillet guy will lay the brass in such a way that shaping and polishing the joints takes nothing more than emery cloth and a short period of time.

Fillets are heavier than tig beads but the amount heavier is often a surprise. Typically the brass used to make the fillets contributes about 2 oz of weight to the frame compared to tig welded construction. Most people find that surprising and expect it to be much more.

As a 'form follows function' guy I think you might appreciate the fact that more often than not a well built fillet frame will have better fatigue resistance than a tigged bike and the ultimate strength can also be higher depending on the tubes used. The thing is that laying of fillets only bring the tubes up to about 1800° F which is much lower than the typical 3500° F used in tig construction. The key difference here is that the heat needed for fillets is low enough that the molecular structure of the tubes isn't altered so the tubes don't lose vital strength during the process. On the other hand tig welding gets the material much hotter and this very often compromises the strength of the tubes and lowers its fatigue resistance. This is why we so seldom see a fillet joint, or the adjacent tube, fail and why it's much more common to see a solid tig joint hold up very well only to have the tube next to it (in the heat affected zone) fail.

Combine this with the fact that the typically larger size of a fillet joint is better at distributing the loads compared to a tig joint and I personally see fillets as being the ultimate 'form follows function' way to hook together steel tubes.

The real downside of fillets is that they are time consuming to make. Tig welding is much faster and then the joint is done, it's done. With fillets it takes longer to lay the fillet, and then the flux needs to be removed, and then typically they are polished to get that classic fillet look. This all take time and in that way tig welding has a real advantage over fillets - and this is of course why the industry moved from fillets (and lugs) toward tig welding. Welding saves time and time is money and that is important.

In the end all three of the popular ways to join steel tubes can make a very nice bike and of course if the tubes are the same the bikes will ride just the same. That said the properties aren't always as they seem and there are hidden advantages/disadvantages for each way of hooking tubes together. Like everything there is compromise and the buyer gets to choose which compromise is best for them.

Thanks for reading - as usual I got wordy and I apologize for that. Have a great weekend.

dave

[soulspinner]

Originally Posted by David Kirk

I don't say this to try to change your mind nor to say you are wrong. If you don't get turned on by fillets I more than respect that.

I suppose the reason I write is to comment on the word "spackled"........it may come as no surprise that I would not chose that term for top shelf fillets. The laying of a tight fillet is every bit as neat and fastidious as laying tig beads and is quite the opposite of what some might think......that a lot of brass is schmeared on with little care and then filed down to look good. A skilled fillet guy will lay the brass in such a way that shaping and polishing the joints takes nothing more than emery cloth and a short period of time.

Fillets are heavier than tig beads but the amount heavier is often a surprise. Typically the brass used to make the fillets contributes about 2 oz of weight to the frame compared to tig welded construction. Most people find that surprising and expect it to be much more.

As a 'form follows function' guy I think you might appreciate the fact that more often than not a well built fillet frame will have better fatigue resistance than a tigged bike and the ultimate strength can also be higher depending on the tubes used. The thing is that laying of fillets only bring the tubes up to about 1800° F which is much lower than the typical 3500° F used in tig construction. The key difference here is that the heat needed for fillets is low enough that the molecular structure of the tubes isn't altered so the tubes don't lose vital strength during the process. On the other hand tig welding gets the material much hotter and this very often compromises the strength of the tubes and lowers its fatigue resistance. This is why we so seldom see a fillet joint, or the adjacent tube, fail and why it's much more common to see a solid tig joint hold up very well only to have the tube next to it (in the heat affected zone) fail.

Combine this with the fact that the typically larger size of a fillet joint is better at distributing the loads compared to a tig joint and I personally see fillets as being the ultimate 'form follows function' way to hook together steel tubes.

The real downside of fillets is that they are time consuming to make. Tig welding is much faster and then the joint is done, it's done. With fillets it takes longer to lay the fillet, and then the flux needs to be removed, and then typically they are polished to get that classic fillet look. This all take time and in that way tig welding has a real advantage over fillets - and this is of course why the industry moved from fillets (and lugs) toward tig welding. Welding saves time and time is money and that is important.

In the end all three of the popular ways to join steel tubes can make a very nice bike and of course if the tubes are the same the bikes will ride just the same. That said the properties aren't always as they seem and there are hidden advantages/disadvantages for each way of hooking tubes together. Like everything there is compromise and the buyer gets to choose which compromise is best for them.

Thanks for reading - as usual I got wordy and I apologize for that. Have a great weekend.

dave

Dave thanks for the explanation. I want one of yours before I go to the big bike shop in the sky...fillets please!