Another day on the wheels (and so on).
From a customer
An Ambrosio
Metamorphosis (Metamorphosis) rim rear wheel
that I received for work.
The hub is a Campagnolo globe-marked Record (naturally 126mm width)
small flange boss hub, 32H, and
it's laced with Sachetti 2.0-1.8-2.0mm butted spokes
in a 66 Italian lacing pattern.
Anyway, I'll be taking it apart, but the customer also pointed out
that the left and right sides of the rim are assembled backwards
relative to the hub.
The rim was shifted abnormally toward the freewheel side.
There was also some lateral runout in one spot, but it wasn't severe enough to account for the shift.
Actually, with this much offset, you'd think centering would be obviously off just by looking
at the gaps between the rim and the rear triangle of the frame.
Nowadays, short nipples are typically 12mm in length,
but these nipples, which look distinctly short,
are 11mm long.
Since I won't be reusing them, it doesn't really matter.
This rear hub's
shape from the left flange outward,
looked familiar to me...
Turns out it matched
a high-low flange rear hub from around the same era that I own.
Boss hubs don't have as severe dish as modern freehubs
(the freewheel side is typically up to 7-speed, at most 8-speed, so the angle isn't as steep),
and this hub, with its quite pronounced high-low flange geometry,
could be considered dimensionally the strongest rear hub.
The outer surface of the rim had dried to its final state
(a point beyond which no amount of waiting will change the color and finish)
of what was likely a slow-setting rim cement bed.
This rim also had the surface treatment I mentioned the other day
to improve cement adhesion. Actually, applying fast-setting rim cement over a slow-setting bed
isn't ideal, but with current Panaracer rim cement,
it doesn't matter—the tire bonds properly.
Since the customer also wants tire mounting after wheel building,
I'll soften the bed somewhat with acetone to remove it partially,
then apply Panaracer cement on top.
The rim isn't particularly light, but since I'm asked to lace it as tightly as possible
during the rebuild, this weight is advantageous.
Hardness varies between silver rims and hard-anodized rims,
with the latter being harder, which is also favorable,
so I should be able to tension it with the same approach as lacing a Nemesis rim.
The R-50 rim from the other day was around 420g,
but if you tension a pipe rim lighter than 350g with modern rim expectations,
it can crack easily—be careful.
Some ultra-light pipe rims weigh less than 300g,
and at that point they're essentially untensionable.
However, they don't reach the threshold where wobbling occurs,
so you can use round spokes with 1.5mm butted sections.
The replacement hub is a Surly Ultra New fixed/freewheel cog hub
in 130mm width.
This hub, in 130mm width for fixed/freewheel cog duty,
only comes in 32H (available in silver and black),
but in 135mm width with disc mount it offers selectable threaded ends
for fixed or freewheel cogs, at 120mm width you get fixed/fixed or fixed/freewheel options,
at 135mm width both-ways (non-disc) you get freewheel/freewheel options,
and depending on spec there are some with 48H options—quite an interesting hub with various configurations.
I don't know which cog gear the customer will use,
but I'll align the rim orientation with the hub shell logo,
so if used as a freewheel cog, the rim lettering orientation
won't be inverted.
The longest available lengths for the spokes I regularly use are:
DT Competition at 303mm,
Sapim Race and CX-RAY at 306mm,
Sapim CX Sprint (threadless) at 310mm
(can be cut down to 270mm as needed).
This hub is 32H with a large flange, but
the flange is smaller diameter than an NJS large flange hub.
With a 36H low-height pipe rim and an NJS large flange hub using 8-cross lacing, you can use 305mm.
That's why Star's NJS 14-15 butted spoke only comes in 305mm.
Pipe rims at 36H don't vary much in inner diameter across manufacturers and models,
so you can either use 304mm (which would be more appropriate) if the spoke threads absorb the difference,
or go with 305mm which works but is a bit tight.
This time I have a slightly smaller large flange hub, 32H instead of 36H,
and to do 8-cross lacing I'll need spoke lengths around 310mm
(6-cross would be around 300mm).
So usable spokes are aero CX Sprint,
or plain, DT Champion which has a 315mm option—that's about it.
The "Yonpachi" lacing—doing true tangential 8-cross on one side of a 28H hub—
is one of the ultimate lacing methods,
but it has the drawback where the non-spoke head path overlaps directly above the anti-spoke head,
and spoke breakage can occur at that contact point.
Aside from external factors like crashes or foreign object entanglement,
spoke breakage normally only happens at the neck, but
anti-spoke head overlap is
virtually the only cause of mid-spoke breaking from regular use.
I've already written so much the images above fade from view,
but the images above confirm through test assembly that a 32H 8-cross lacing
doesn't have problematic anti-spoke head overlap.
With a sufficiently large flange, the geometry works in your favor,
so I thought it should be buildable.
Built it.
32H, all CX Sprint, 8-8 JIS lacing with
orange alloy nipples.
I'll do the truing later.
Separate from this wheel, for cyclocross or MTB use,
but recently requests for silver CX Sprint with orange alloy nipples
have been increasing for some reason.
Anti-spoke head overlap is
occurring slightly, but at this level there's no problem.
Bonus:
Beyond true tangential lacing, the pattern with highest spoke-pulling risk is
"Double cross," where spokes are woven one cross before the final crossing, and
"Flower" lacing, where twist is added one cross before the final crossing.
These increase the risk of nipple pull-outs
but don't cause mid-spoke breakage.
From a customer
An Ambrosio
Metamorphosis (Metamorphosis) rim rear wheel
that I received for work.
The hub is a Campagnolo globe-marked Record (naturally 126mm width)
small flange boss hub, 32H, and
it's laced with Sachetti 2.0-1.8-2.0mm butted spokes
in a 66 Italian lacing pattern.
Anyway, I'll be taking it apart, but the customer also pointed out
that the left and right sides of the rim are assembled backwards
relative to the hub.
The rim was shifted abnormally toward the freewheel side.
There was also some lateral runout in one spot, but it wasn't severe enough to account for the shift.
Actually, with this much offset, you'd think centering would be obviously off just by looking
at the gaps between the rim and the rear triangle of the frame.
Nowadays, short nipples are typically 12mm in length,
but these nipples, which look distinctly short,
are 11mm long.
Since I won't be reusing them, it doesn't really matter.
This rear hub's
shape from the left flange outward,
looked familiar to me...
Turns out it matched
a high-low flange rear hub from around the same era that I own.
Boss hubs don't have as severe dish as modern freehubs
(the freewheel side is typically up to 7-speed, at most 8-speed, so the angle isn't as steep),
and this hub, with its quite pronounced high-low flange geometry,
could be considered dimensionally the strongest rear hub.
The outer surface of the rim had dried to its final state
(a point beyond which no amount of waiting will change the color and finish)
of what was likely a slow-setting rim cement bed.
This rim also had the surface treatment I mentioned the other day
to improve cement adhesion. Actually, applying fast-setting rim cement over a slow-setting bed
isn't ideal, but with current Panaracer rim cement,
it doesn't matter—the tire bonds properly.
Since the customer also wants tire mounting after wheel building,
I'll soften the bed somewhat with acetone to remove it partially,
then apply Panaracer cement on top.
The rim isn't particularly light, but since I'm asked to lace it as tightly as possible
during the rebuild, this weight is advantageous.
Hardness varies between silver rims and hard-anodized rims,
with the latter being harder, which is also favorable,
so I should be able to tension it with the same approach as lacing a Nemesis rim.
The R-50 rim from the other day was around 420g,
but if you tension a pipe rim lighter than 350g with modern rim expectations,
it can crack easily—be careful.
Some ultra-light pipe rims weigh less than 300g,
and at that point they're essentially untensionable.
However, they don't reach the threshold where wobbling occurs,
so you can use round spokes with 1.5mm butted sections.
The replacement hub is a Surly Ultra New fixed/freewheel cog hub
in 130mm width.
This hub, in 130mm width for fixed/freewheel cog duty,
only comes in 32H (available in silver and black),
but in 135mm width with disc mount it offers selectable threaded ends
for fixed or freewheel cogs, at 120mm width you get fixed/fixed or fixed/freewheel options,
at 135mm width both-ways (non-disc) you get freewheel/freewheel options,
and depending on spec there are some with 48H options—quite an interesting hub with various configurations.
I don't know which cog gear the customer will use,
but I'll align the rim orientation with the hub shell logo,
so if used as a freewheel cog, the rim lettering orientation
won't be inverted.
The longest available lengths for the spokes I regularly use are:
DT Competition at 303mm,
Sapim Race and CX-RAY at 306mm,
Sapim CX Sprint (threadless) at 310mm
(can be cut down to 270mm as needed).
This hub is 32H with a large flange, but
the flange is smaller diameter than an NJS large flange hub.
With a 36H low-height pipe rim and an NJS large flange hub using 8-cross lacing, you can use 305mm.
That's why Star's NJS 14-15 butted spoke only comes in 305mm.
Pipe rims at 36H don't vary much in inner diameter across manufacturers and models,
so you can either use 304mm (which would be more appropriate) if the spoke threads absorb the difference,
or go with 305mm which works but is a bit tight.
This time I have a slightly smaller large flange hub, 32H instead of 36H,
and to do 8-cross lacing I'll need spoke lengths around 310mm
(6-cross would be around 300mm).
So usable spokes are aero CX Sprint,
or plain, DT Champion which has a 315mm option—that's about it.
The "Yonpachi" lacing—doing true tangential 8-cross on one side of a 28H hub—
is one of the ultimate lacing methods,
but it has the drawback where the non-spoke head path overlaps directly above the anti-spoke head,
and spoke breakage can occur at that contact point.
Aside from external factors like crashes or foreign object entanglement,
spoke breakage normally only happens at the neck, but
anti-spoke head overlap is
virtually the only cause of mid-spoke breaking from regular use.
I've already written so much the images above fade from view,
but the images above confirm through test assembly that a 32H 8-cross lacing
doesn't have problematic anti-spoke head overlap.
With a sufficiently large flange, the geometry works in your favor,
so I thought it should be buildable.
Built it.
32H, all CX Sprint, 8-8 JIS lacing with
orange alloy nipples.
I'll do the truing later.
Separate from this wheel, for cyclocross or MTB use,
but recently requests for silver CX Sprint with orange alloy nipples
have been increasing for some reason.
Anti-spoke head overlap is
occurring slightly, but at this level there's no problem.
Bonus:
Beyond true tangential lacing, the pattern with highest spoke-pulling risk is
"Double cross," where spokes are woven one cross before the final crossing, and
"Flower" lacing, where twist is added one cross before the final crossing.
These increase the risk of nipple pull-outs
but don't cause mid-spoke breakage.