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Re: The bicycle thread

Beautiful sand_man

Re: The bicycle thread

Originally Posted by WeldingMachine

that is really cool sand man!

Thanks, here it is all done.

Attachment 1662171

Re: The bicycle thread

that is really cool sand man!

Re: The bicycle thread

Ready for a test ride.

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Re: The bicycle thread

some very nice work in here

Re: The bicycle thread

Start of a new project. I did try 1-2 hz 33% on and 33% background amps. Clearly I didn't get the results above but I was overall happier with the settings compared to just straight pedal control.

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Re: The bicycle thread

Hello to the bike builders in the welding web.
I´m new here and just introduced myself to the forum a few days ago ("Hello from Germany" there you will also find a few pics of my work).
I started a framebuilding business 12 years ago. Normally I tig weld (90%) but some frames are fillet brazed with oxy azetylen.

I´m allways interested in the settings other builders use and found an interesting clip from an italian builder. Before watching the clip I allways wondered about his settings because his results are stunning in my eyes.
Here is a picture of the results he gets.

Attachment 1545821Attachment 1545831

He uses a pulse frequency of maybe 1hz, and a very very short peak time (just like a short flash).
That leads to a very small haz, a flat and wide bead and nearly no burn through.

I think I will try something similar once. But missing experience might lead to a lack of root penetration. Thats my concern.
What do you think?
Is there anybody using a similar welding style?

Kai

(Sorry for my english, it´s a while ago that I went to school ;-)

Re: The bicycle thread

Could be that I used a flap wheel that day. I always go over everything with carbide burr so doesn't matter if I use the black cutting disk. I would just leave it as is and weld it out after just cutting with the blade disk, there more prep after cutting each time. Attachment 1530651Attachment 1530661and it broke in my bender. Not even sure if I had 6061 or 5052, and used 5356 rod, gona go get 5052 and use 4043 next time. It didn't brake all the way tho lol. Bend testing AL is way harder then steel( in welding the pieces out correctly terms)

Re: The bicycle thread

Try the black discs made for aluminum, they're a bit cleaner.

Re: The bicycle thread

Originally Posted by Brazin

That aluminum is a good example of why folks cut aluminum with a carbide blade, instead of grinding wheels, the grit gets imbedded in the material and comes out in the weld.

i disagree that it's from the black grinding disk. Pretty sure I was moving a bit fast that day and we're looking at a gas covered issue. All I ever cut my meterials up with is a black thin cutting disks pretty much, sometimes my buddy's band saw

Re: The bicycle thread

That aluminum is a good example of why folks cut aluminum with a carbide blade, instead of grinding wheels, the grit gets imbedded in the material and comes out in the weld.

Re: The bicycle thread

Attachment 1529801

Stainless will... Leave that box outside for a year - the HAZ will rust if it's contaminated. It's not really the blade, it's the temperature that it gets the stainless to while cutting that allows for atmospheric contamination, and the abrasive blade doesn't help for the carbon uptake. Chromium carbide precipitation is a bitch...

Not sure about aluminum, but it doesn't really get that hot during prep. I actually can't remember getting aluminum glowing while cutting, machining, or grinding. In the case of the video I remember 4130 being more sensitive to atmospheric contamination, and thought it was odd that he would jeopardize the parent material before it even gets welded. The idea behind it is adding carbon to 4130 in the austenitic region then cooling rapidly is going to make the material brittle at the joint past the leg of the fillet - this would make the frame prone to cracking after the weld. Almost every frame I cracked, and have seen cracked was 1/8"-1/4" away from the leg of the fillet. Post weld heat treated frames don't suffer from this problem as much - that's the process Odyssey uses in their fork production.

Re: The bicycle thread

Originally Posted by pantelones

I just found this...

https://vimeo.com/141268107 (no idea how to in-bed Vimeo, click link to see the processes behind the following...)

Attachment 1503581

I'm not sure if I like that he's using an abrasive chop saw and grinding the copes instead of cutting... He states exactly why too - you ruin the molecular structure and I noticed when I did my stainless exhaust - an abrasive saw is enough to contaminate the base metal. The weld can look beautiful, but the parent material is compromised.

Mike is still very good at what he does, and maybe there is something that I'm not seeing...

I disagree here. I even use the black cut off wheels with aluminum and it's ok. Attachment 1528721Attachment 1528731

Re: The bicycle thread

I built my first frame last year. I've got about 2000 miles on it so far, mainly winter commuting. I just painted it black and getting it ready for more winter base miles/CX/gravel and general crap weather riding..

Re: The bicycle thread

I just found this...

https://vimeo.com/141268107 (no idea how to in-bed Vimeo, click link to see the processes behind the following...)

Attachment 1503581

I'm not sure if I like that he's using an abrasive chop saw and grinding the copes instead of cutting... He states exactly why too - you ruin the molecular structure and I noticed when I did my stainless exhaust - an abrasive saw is enough to contaminate the base metal. The weld can look beautiful, but the parent material is compromised.

Mike is still very good at what he does, and maybe there is something that I'm not seeing...

Re: The bicycle thread

Originally Posted by zank

Sorry for the slow response! Happy to help.

For filler, I'm generally running 880, but I do run ER70S-2 on certain things. When I weld bridges and canti studs, I usually use the ER70 because I have a hard time getting a really good back purge on those pieces. I run 0.035" rod for pretty much everything. In the areas that require a bigger fillet, I just push more wire. It's not a dab; it's more of a push. I like having that control. In terms of nice and shiny though, I think that is more a function of coverage, prep, and speed. The BB cluster below was done with ER70S-2. The bead itself is not as silver as the 880 beads, but ER70S-2 beads don't need to be gray either. I actually think prep and cleaning is something that is often overlooked. Start with bright shiny steel, clean with acetone, clean the filler with acetone. And another thing I see fairly often is guys pulling the torch away very quickly and not protecting the bead with the postflow.


Lonny G by Zanconato Custom Cycles, on Flickr

Hope that helps. Hit me up with any other questions. Have fun!

Man, your work is absolutely amazing...truly impressive and admirable.

Also: "Very good, this Italian workmanship. People pay more for quality."
Anyone identify the quote?

--Wintermute

Re: The bicycle thread

This LWB USS was a sweet ride. Whole new muscle group in use there.

Re: The bicycle thread

This thread takes me back. That Knuckleduster looks a lot like a bike that Bryan Fuller did some years ago. I saw it on line and proceeded to build my own version around 12 years ago. Used a Shimano 7 speed rear hub with coaster brake. Had the rear wheel laced up with moped spokes. Frame is powder coated. Tank holds tools, tubes and a beer. Put on about 2600 km doing MS Bike tours and just having a good time bs'n with folk who were quite amazed the bike was built by me. Did up a couple LWB underseat steer recumbents before that one.

Re: The bicycle thread

Thought this was pretty cool...

Re: The bicycle thread

That turned out nice Sand man red!

Re: The bicycle thread

Awesome!

Cargo bike conversion

For my daughter in law. Started with two old Schwinn bikes. Main lower tube is 2.25 OD 14 g, mandrel bend and rise is 2.25 OD 16 g. Gussets on lower tube are 16 g. The whole bike assemble weighs around 75 lb which is heavy but not crazy for a cargo bike. I've ridden it with 80 lb in the bucket. I've had another person my size ride it with me in bucket, I'm about 150.

Need ideas on what to mount in the forward neck. I found a cool cast aluminum skull but the wife nixed that idea...

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Re: The bicycle thread

Originally Posted by zank

Thanks for the kind words, Kavall!

Not much to add after your explanation of the brazing process. The lugs are cast over in Taiwan. The company that makes them makes the best lugs in the world. Beautifully cast and help to very tight tolerances for socket dimensions.

I use a silver brazing rod that is 48% silver. Flows very nicely.

Do they make the "old school" sets like Nervex Pro's? Those were beautiful.

Re: The bicycle thread

Originally Posted by Independent

Zank,

Been lurking here on the forum for awhile now and decided to sign up just to post in this thread. Really like the quality of your frames. I am starting to build a few custom ones myself. Here are a few pics of the ones I have finished.

This one is called lithium, both for its calming tendencies while riding and the Nirvana song.







This one is called Knuckle duster. The triple trees look like brass knuckles.





I have some pics of Knuckle Duster finished but have to find them.

This is the next one. Hope to finish it this year.

Holy Moly, those are long chains.

The Lithium would look awesome with a linkage fork.

Re: The bicycle thread

Zank,

Been lurking here on the forum for awhile now and decided to sign up just to post in this thread. Really like the quality of your frames. I am starting to build a few custom ones myself. Here are a few pics of the ones I have finished.

This one is called lithium, both for its calming tendencies while riding and the Nirvana song.







This one is called Knuckle duster. The triple trees look like brass knuckles.





I have some pics of Knuckle Duster finished but have to find them.

This is the next one. Hope to finish it this year.