mostly the BB drop puzzles me. I looked at the sequoia geometry and they have drop increasing as you go up the size range. Generally you would see the opposite since a smaller frame will usually get shorter cranks.
Do you have any TIG experience? Aluminum is easier in some respects IMO. More sensitive to cleanliness but it’s fast and the bead/puddle are much bigger and easier to see.
I have an everlast 200DV, very attainable machine cost wise and distribution is through big box stores in the US.
It would certainly be weird if it was the case. I think it’s a typo though. I referenced the other year and it was the same numbers but in the sensible order. I guess an intern spaced or something because the BB Drop lines up year to year if you switch the smallest with the biggest and so on. I think I will bring it down some though.
The other thing I just thought of is that if you increased stack to lose a spacer but kept reach the same you will effectively increase the reach… though 10mm increase in stack won’t make much difference.
Just something to keep in mind if you plan to use the same stem length.
Are you using the stock torch or did you upgrade?
@Gary_the_tennis_ball what wheel/tire size are you planning?
I upgraded the torch and pedal through them. Up here there is a distributor that sells direct.
I have a 17 sized air cooled flex head torch. I use gas lenses and #8 cups for pretty much everything. 1/16” tungsten for steel frames and 3/32” for aluminum. Ceriated or lanthanated on steel and lanthanated on aluminum.
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a nice CK torch setup is less than $200.
Is it common to ask frame builders about their tolerances? If you’re designing this with thin margins in some area I’d want to double check so you don’t end up with say not enough tire clearance or some other annoying limit.
If this is for a 2x up front think about bottle boss placement vs. front dangler band clamp location, and maybe front dangler band and arm vs. rear tire.
Bro the front is a pusher
The rear is the dangler
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You mean in the sense that the reach gets longer to compensate for the stem top of the headtube moving closer? Like the reach is “longer” as far as the stack:reach ratio? I’m not sure I follow but this sounds like something I should understand.
@drwelby and @jimmythefly it’s built/modeled around 700x45ish. Will likely usually have 700x38s. 1x would be the plan for this bikes lifetime, but I’ll do the due diligence for pusher for the practice
You slid the headtube forward so a higher point on the frame
has the same reach number
It’s hard to explain but I think you get it.
If you imagine the same bike with spacers and without, the stem moves forward as you remove spacers because of the headtube angle. So if the original frame has 387mm reach and you want to fit the same way but have 10mm more stack you would want the reach to be slightly shorter to account for the spacers you were running before.
In this case it’s 3.2mm (it’s a right triangle problem). Not that relevant but if you were changing the stack more it would be important to take into account.
Ahh yea I getcha. Changing the STA scoots me forward a little under 6mm from the original geo, so I think it’s probably pretty close to a wash. It’s interesting the bottom brackets are so high, but I never felt like it was a problem so I think I’m gonna round it to 67, maybe 68mm of drop and then call it good.
Thanks for all the help!
but doesn’t the stack come back towards you? so increasing the height of the stack would slightly lessen the reach, but if you go to bottom of stem (assuming same location in space) wouldn’t you want slightly less reach?
Yeah that’s what I was trying to get at.
In this case reach is 387 on the original. If you want the new version to fit the same but with 10mm more stack, the new frame should be 384mm reach.,
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oh, no. that’s exactly what you got at. i just can’t read tonight apparently…
So I think I’ve got a bad tank of argon. Since I started the aluminum bike I’ve been getting more and more unpredictable results on the practice stuff I’ve been doing. Last night at the tail end of an hour or so of trying to run a decent bead on some scrap while trying to rule out any other issue things just went to shit. Did some research and sounds like it’s a classic sign of moisture in the tank, gets worse the more you draw from it. Going to bring it in after work to swap for a new tank. Fingers crossed it’s that and not a busted welder.
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Update: not the argon tank. Pretty sure my torch is fucked. Gas flow is there but I’m getting contamination somehow or another. Ruled everything else out.
Water in the hose?