Process shots from Adam’s 29+

Adam’s frame is 95% done. I just need to cap the wishbone stay ends, put on a few cable guides, ream/face, and clean up before posting any final parting shots.  It was a challenging build not just because the bent tubes but because it was so interrupted by time away from the shop. I have to say, if i wanted a custom 29+ this is what I’d order too.  Maybe with internal cables though.  I’ll post geometry and more details when I post the ‘final’ shots before it goes to paint. But for now here are some process shots for the FB dorks out there.

I’m a pulser now

On the rear triangle of the latest frame, my new super fat rotundcycle, I test-drove the pulser on the ThermalArc 185.  I started trying it when I had poor line-of-sight on the elevated chainstay bridge and I thought it’d help with heat control on those tight spots.  But after I got done with the bridge I just kept going. I always have done ‘straight amps’ but wanted to see if I could get more consistent looking beads and less heat distortion by using the pulser.  Also, I realized on the last few frames that I was foot-pulsing more than normal, mostly in the acute angles – under the downtube, countermiter of downtube/seat tube.  I was also finding myself not dabbing the filler road and just laying the wire in there for the high part of the foot pulse to “absorb” into the bead.  Laying the wire in there with tension (pushing it in there) also acts to close or block those small miter gaps that you just didn’t feel like filing any longer to get water-tight.  So when using the pulser previously I felt like I was losing control but something has clicked in my brain recently.  The pulse heats/cools so you should get less ovalization/heat distortion and it also gives more control over how the bead looks aesthetically.  I could also lay longer passes and minimize my starts/stops, and my welding isn’t as affected by tired hands and arms which would make me more shaky when using straight amps and dabbing the filler.

platform-welded

I didn’t take many pictures of the frame welds other than of the E-stay junction.  I set the peak amps to 100, the ‘background current’ to 25 amps, the frequency at 1.7pps, and the pulse width at 45%. I used the foot pedal to regulate the amps based on the tube wall thickness instead of futzing with the pulser settings for each joint.  I could weld the BB with a heatsink to the seat tube with these settings as well as the hooded dropouts to the stays.  Unless I was going to be using something less than 0.7mm wall tubing, I may just stay with those pulser settings.  I’m using the next frame, a new geared cross bike for me, for further experimentation with the pulser to get it dialed in before taking on friend’s bikes.

upperview-e-stays

The downtube is a 38mm Supertherm (1/0.7/1 butt profile) and the butt is just above where the elevated chainstays join the downtube.

I also used the pulser on my first stem. The steerer clamp and bar clamp/front plate are Paragon’s sweet Machine Works. I just mitered the 1.125 x 0.049″ tube to make this a 90mm x 8 degree rise stem and welded if up in the fixture that has been too long a really expensive paperweight till now.  These are so quick to make using the Paragon parts, but they are super expensive.  Really no need to make stems, but it is a nice touch to a custom frame and pretty sweet looking in my opinion.

Stem1-weld

Stem1-weld2

stem1-done-2

TIMMAY’s bike almost done

Some photos of the process and results.  The welding of the front triangle and chainstays went well.  I tacked in the fixture at 12 and 6 for most tubes except for the top of the downtube where I tacked at 10 & 2.  Before removing it from the fixture I welded a full pass to connect those tacks. I remember doing ‘cosmetic’ passes with the pulser over almost all my 1st pass welds on my first several frames.  No longer! The 1st pass is good as is these days (for the most part).

One “fun” thing I tried was NOT facing the BB shell and loading it up on the alignment plate and seeing how it all lined up.  The seat tube was spot on. The head tube was sub-1mm up (non-driveside). That’s good enough for me! But then I chased threads and faced the BB shell and loaded it up again on the plate.  This time the seat tube was up 0.7mm and the head tube was dead on.  So there you have it (N=1). There was a little non-uniform warpage of the BB shell as to be expected (duh) but surprising to me is that it really didn’t change much of the overall ‘alignment’, or at least how I measure it and to my level of care.  Mostly the facing helps the bottom bracket thread in there and sit flush against the shell.  What it told me more is that my welding is getting more uniform in heat control – meaning on each 1st pass I am consistent and not pulling the frame around in any way it’s not supposed to go.  My miters are tight and with good heat control the bike stays put even if you don’t weld it up in the frame fixture!

More words later when I show off my first schweet S-bend stays!

TIG troubleshooting

photo

Some days I wonder if an alien hasn’t already taken over my body. Am i getting too old to learn and retain new tricks? Am I over-caffeinated, or under-caffeinated?

Just as keeping yourself physically fit, it’s important to keep the muscle memory strong by practicing welding even if you’re not building a bike at the moment…and I haven’t been keeping up my welding fitness lately. I’m been doing different things lately like working on my machining skills and creating a couple easy new fixtures so that I can do things easier and faster. I made a kinda cool wishbone seatstay fixture that I’ll blog about later when I have some tubes in it to show off. I got the horizontal milling machine set up with a 4-jaw lathe chuck so i can face head tubes and make seat tube collars and who knows what else. I swapped the Anvil MTMF onto that same horizontal mill since I got the horizontal baseplate from Anvil on Friday just to try it out. And I’ve started a fat fork for Scott W and the mitering has begun for Russell’s all-mountain frame.

But there was something that happened to my welding that I couldn’t pinpoint. I wasn’t sure if it was something i was suddenly doing differently, a broken part, or whether I’m just simply out of practice. I tried new Weld-tec gas lenses, new tungsten, a new torch head even to replace the WeldTec flex-head to see if I was getting some oxygen contamination…but nothing solved it. It’s the same tank of Argon (from Colorado) that i had last two frames so it couldn’t have been that. Next in line was the aging dirty and worn Superflex cable but I wasn’t hopeful.

The problem? I was getting a little arc wavering on my last frame’s head tube that was not due to torch angle (below pic). I was getting more HAZ discoloration and different colors than I’m used to. I was getting more sputtery starts and more splatter along the bead. I was cleaning tubes the same way and even got a little in-line air compressor filter just to be safe. But the below picture shows some of the weirdness even thought it’s not a bad weld.HT-weld-rainbow

I just was not getting that clean clear puddle and smooth movement of the puddle as it melts and cools. It was almost like a hundred more puddles were showing up and cooling along the way so that I didn’t get that nice stack of dimes like I had here only a couple of months ago:

BB welds

Sometimes framebuilding reminds me of when i raced and my main weakness was my head. I would get so nervous before each race, and then while racing I couldn’t keep my head in it.  I’d be looking at the views and the wildflowers on 401 in Crested Butte as i raced past and thought to myself, ‘why am i doing this? i should stop and sit on that bench and smell the flowers‘. But I didn’t and kept going because well… it was a race!  I excelled somewhat at it because I gained pretty good fitness from loving to ride but also because of sheer stubbornness and high expectations of myself. But even when I had good races, I always felt bad for the guys I beat. WTF? My head plays games with me – a conflict of high expectations and not handling the pressure well.

Apparently the same goes with the pressure and expectations I put myself behind the torch. I know how to do it, it’s just doing it that’s the hard part sometimes. Call it the pre-race jitters, performance anxiety, or just lack of confidence, it’s really just a pain in my ass.  But I will rack my brain until I do it right and I will never give up unless it’s based on circumstances beyond my control or because I no longer enjoy doing it. Neither of which apply to this situation.

So after beating my head against the welding table and having another one of those ‘about-to-give-up-framebuilding-frustration’ moments I gave it one last try. I mitered some scrap 1.125 x 0.035 and made my last ditch effort at troubleshooting and swapped out the Superflex cable. That’s when I noticed it…the gas input valve on the Dinse connector was loose. I must have been getting a little bit of oxygen mixed with my argon purge.  It probably unscrewed itself a bit when I moved my welder from against garage door to more in the middle of the shop. It’s hard to keep this inlet tight because when you turn to lock the Dinse knob the gas inlet is on the bottom and can twist itself loose if you aren’t careful.

Once i tightened the argon inlet and started welding all was better.  No matter which torch I used i got some good beads. But as it turns out I liked the CK torch the better than the WeldTec that I have been using for the last two years.  The CK130 is smaller, lighter, and now that I know what a flex-head will eventually do to my welds i am retiring the Flex-head torch. I’m not sure if i was imagining it, but the CK torch had cleaner faster starts with no stuttering. Same lens, cup, and tungsten. N

So there it is…all that mental toil for nothing. Back in business.

WeldTec WP-9F on left, CK130 size 9 on right.

Can't remember what torch.
CK130 torch
CK130 first bead

CK130 posing next to its work

WeldTec results

WeldTec results.

Knard bike starting to take form

It’s been awhile since I posted photos on this frame I started months ago…slow progress because of the move and holidays! So here are some shots just to look at. The welding of the tubes I’m welding and not brazing on the front triangle are done. They look different than what I usually put out. It must be my spirit star pulling towards Venus instead of Mars. Yep, that’s it. The puddle was plenty hot enough, just looks different because I was cruising through the beads. The finish on the Paragon head tube definitely makes for some cool looking heat affected zone (HAZ) coloring. It’s funny how fast I can weld when I’m working on my own frames vs. frames for friends. I worry less and I end up just getting in the zone like I actually know what I’m doing…and it’s super fun. Definitely get in more of a groove. Welding is definitely my favorite part of building up a bike.

Trying some Retrotec-esqe twin top tubes on this frame that I’m making for myself. I’ve never owned a Retrotec, but i’ve always loved them. I even tried pretty hard to get on their racing team back when Bob Seals was still the owner and wore a pink speedo at Mammoth while racing his singlespeed. I guess I just wasn’t cool enough for their bus. I also didn’t smoke enough pot. So anyways, I thought I’d emulate and make one for myself after all these years.

I got the 5/8″ SWAG dies for my tube roller and rolled the top tubes. Bending tubes on the roller is really easy, it’s the mitering and keeping the miters in phase of bent tubes that’s the hard part. The Anvil MTMF makes it way easier though since the V-blocks keep the bend in phase.

I’m using the new 29er chainstays from Dedacciai for the first time. They have a big 26 degree bend and are S-bends so are really the only thing I could try and use with the big Knard tires (which I still don’t have) unless you bend your own. I still had to dimple them for clearance. I may go with a wider BB shell for the next build depending on how this turns out and I can actually test the tires in the frame. Drawings are great and all but nothing substitutes for the actual parts in-hand.

Tig pulsing practice

top = pulser
bottom = no pulser.

I did some practice welds on some 1.125″ x 0.035″ and tried out the pulser again just for fun.  I still am not sure I’ll ever weld a frame up with the pulser, but after tonight I am considering it. I’m definitely getting better!The top weld is with the pulser (84amps peak, 12amps bottom, 45%, 2hz).  The bottom bead is straight 64 amps with my foot regulating the input depending on what I felt was needed (in all fairness, my first bead was the non-pulsed and I am out of practice by a couple of weeks). These tubes are 0.047″ wall scrap OXPlat steerer and 0.035″ wall 4130 that was mitered in the new fixture (pretty thick tubing but good to practice on).  Surprisingly, the pulsed weld looks much better than my regular way of doing it.  Out of practice i guess. Or just got lucky.  I laid the filler rod in the joint and put pressure down into the joint while moving the torch along at a not fast but not mellow pace.

The thing I have noticed with the pulser is that you have to trust it. If the miters are really good, and you don’t ball up the filler rod, it’ll lay a really nice bead. If the miters aren’t tight, you can get holes in the tubes pretty quickly…and you can’t see them come on until they’re there. I’m sure the good pulser guys micro-adjust their foot pedal a little so that doesn’t happen, but I’m still trying to focus on not poking the filler rod in the puddle and just laying it down.  It does feel like I’m giving up a little control by using the pulser, but the results can be very aesthetically pleasing, if not necessarily better in penetration or joint strength.  With the pulser, it’s easier to get each ‘dime’ exactly the same size…looks more consistent.  I’ve definitely had straight-amp welds look like this, but just not as frequently or consistently as I’d like. I read somewhere — “perfect practice makes perfect.”  This is something I frequently think about when i consider not spending more time getting the tightest miters, or giving the inside of a tube a good scrub cleaning, or skipping a step because of time constraints.  Do it right the first time, or it’ll haunt you later on. This is definitely true with practice in TIG welding.

 

Ups and downs with tig-welding

It’s been a pretty frustrating week in the shop.  Not a lot of time, and the time in there was usually undoing/redoing my mistakes from the previous day. Groundhog day for the last week or so. It’s weird, i just can’t get out of this rut!  I know I’m still a newb, but I feel like i just started welding again. It’s like my brain and body took a hiatus and left this stupid dude that just stares at stuff clueless to why anything is going wrong!

Anyways…

Tig welding is the most awesome and frustrating thing I’ve ever learned.   I’d been putting off welding up the front triangle of Jim’s cross frame until I felt more back to ‘normal.’  Today I went after it, and even though I had some not-so-pretty results around ‘tongs’ of the counter miter of the BB/ST/DT (the hardest part to weld IMO), it’s done, and it’s all pretty good.  I haven’t checked the alignment yet (I got caught up starting to make my own seatstay fixture…more on that fun later!) after spending an hour welding up the front triangle and chainstays.

“If you put 10 framebuilders in a room and ask them how to weld up a frame, there will be 12 different answers.” – Don Ferris.

“Keep your process exactly the same for each frame so you can see what works and what doesn’t in terms of frame alignment.” – Carl Strong.

(Ok, so I’m paraphrasing those quotes, but they are more or less what I heard and read, respectively, from those two builders.  A newb has trouble fixing their alignment issues if they don’t change their process, so I’ve basically thrown Carl’s advice out the shop door (I don’t have a window).  I’m not getting Carl’s whole point across in that paraphrase => he was saying that if you change too many things at once, you’ll never know what is working and what isn’t…so leave at least the welding sequence constant and any variation that results in frame alignment will be easier to discern where it came from…or something like that.)

Another rather large tip I got from Mr. Ferris was to only tack-weld the frame in the fixture in the vertical plane ONLY.  This definitely runs counter to how I learned from Mr. Kopp, and what I’ve interpreted on the online forums.  I’m not sure I’ll stick with it but it does seem to make sense to me.  I thought I had heard him wrong at first, but I’m pretty sure this is what he was recommending.  (Who knows, maybe he’s totally f’ing with me.)  Regardless, I gave it a try.  The one problem is that he recommended welding the acute 1/4’s in the fixture FIRST (10-2 on the top tube, 4-8 on the downtube), then the obtuse angles before taking it out of the fixture and welding the rest on the stand.  This was confusing to me because I’ve always heard to weld the obtuse angles first, then the acute angles since the steeper angles tend to draw together more than the obtuse angles.  The reason behind welding the acute angles first in the vertical plane is exactly that though – because doing so securely draws-in the head tube to the TT & DT.  I do tack weld the obtuse angles first and acute second though.

Also, don’t stay on one tube for the whole welding sequence…split it up so that the tubes on that particular joint don’t build up heat and start acting differently under the same amperage.  I’ve noticed this, once hotter, tubes act differently.  Move to the top tube/head tube before finishing off the down tube/head tube joint.  Once the vertical 10-2/4-8 welds are done, then weld up the sides. Weld in 1/4’s if you can, but honestly, I can’t…i weld in 1/6’s.

So, I followed these recommendations for the most part – except for welding at all in the fixture – because I like to use heat sinks to minimize ovalizing/distortion to the head tube and BB (and save my reaming/facing tools).  It’d be easy to weld the vertical planes on the joints in the fixture, but I know that I’d have more distortion than I’d want, so after tacking I took the frame out of the fixture and welded in the bike stand attachment on my welding table.  It’s just SO much easier to flip flop it around to get the right position and sighting on the joints that way.  The heat sinks and the backpurging are the main reasons my welded tubes don’t have much discoloration even though I’m at around 64amps floored most the time. (It seems each machine has a different 60 amps though…and maybe air vs. water cooled torches make a difference too…i don’t know.  But I do know that I learned on a huge fat Miller Synchrowave 200 and was burning through at 32 amps.  My little inverter 185 seems ‘cooler’ at the same amperages. I’m probably high on argon so maybe that’s totally wrong…)