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Tuesday, November 21, 2023

DIY carbon repair

Backstory

In 2016 I crashed my 2013 Sworks with 2km to go at Masters 50+ Nationals when someone slid up between me and another rider and took my rear derailleur off. The major problem from that incident was tremendous sciatica, which turned me in to "The Falls Church Night Weirdo" for the entire summer. But in addition to my piriformis muscle , the seat stay was also damaged. The drive-side seatstay crack had been growing for years, while I  monitored it. By Spring 2021 it was large enough to affect the shifting, and I retired the bike. I had already had it repaired once before in 2015, after an Artemis guy chopped me at the Tour of Page Valley, and either my heel or the heel of the guy I fell on cracked the chainstay. 



broken seat stay
The crack in the seat stay extended about 2/3 of the way around.

Since the frame was a writeoff at this point, a repair attempt seemed like an entertaining retirement project. As everyone does, I watched about twenty youtube videos on DIY carbon-fiber repair. I ended up buying a kit from Predator Carbon: https://predatorcycling.com/products/carbon-repair-kit , mostly because their videos had seemed useful. I actually bought the individual components instead of their pre-packaged kit, because it was only 3/4 the cost. 

All the repair kits I have seen from various sources are similar. Mine had three components:
  1. a strip of 2x2 twill-weave carbon fiber 150 mm x 1300 mm,
  2. 75 ml of resin with catalyst, and 
  3. 2 m of industrial heat-shrink tape.
The third component is the "secret sauce" that makes the whole process work for the neophyte end user. The heat-shrink tape provides the compression over the fiber layup to squeeze  out the excess resin and compact the layers.

The kits represent a big markup over the marginal cost of materials, but most carbon fiber suppliers only sell in much larger, and ultimately wasteful, volumes. My experience was that the 75 ml of resin is sufficient for four or five repairs. And it has a very finite shelf life, so buying a 4 liters just means that 3.9 liters will go to the solid waste transfer station.

I practiced once using Marc Klein's Cannondale that Pete Lindeman had given me. I smashed the top tube on the concrete steps and then patched it.  After the resin had cured, I sawed a section of the tube out from the repair and verified that the patched area didn't contain unconsolidated fiber/resin. 

For the Sworks Chainstay repair, I opted for a simple three-layer overwrap, instead of attempting to create a scarf joint. The resulting repair will be a bulge like a recently healed broken leg, but more layers seem safer than a more attractive repair. 

The Repair

First I removed the clearcoat by hand sanding 5 cm on either side of the crack. 

Crack with the clear coat removed.
The crack with the clear coat removed, and prepped for an overwrap. 

Mixing the resin and catalyst is straightforward by weight: 3.5:1 . I used the triple-beam balance that I rescued off the loading dock of Bard Hall 35 years ago. 


The twill-weave carbon fiber cut to size, and the components ready to weigh out. I mixed them with a recycled Trader Joe's popsicle stick in a used a carry-out sauce container . 


I masked the area of the seat stay with painters tape and electrical tape, and I wrapped the entire frame in newspaper and garbage bags, which is important, because the resin runs out and drips everywhere.  One of the videos suggested tacking the end of the carbon fiber sheet in place using partially cured (40 minutes) resin, so I did that.  

Before wrapping, I staged the the correct length of heat shrink tape by taping it to one size of the repair area, so it would be quick to just wrap it around. 

With the resin and catalyst mixed, I painted the whole exposed section of the seat stay with resin using a plumber's acid brush and started wrapping the carbon fiber sheet, while simultaneously painting more resin onto the new layer. The entire repair was three layers of sheet, which makes a repair about 1.0 mm thick.

With everything in place, I spiral wrapped the heat-shrink tape like a handlebar, overlapping about 50 % of the tape on each wrap. Then I taped the end with electrical tape and hit the whole area with the heat gun for about 90 s. As the tape shrunk, it squeezed out the excess resin, which I (mostly) wiped up with a shop towel. Some dripped on the floor, unfortunately. 


The repair after the tape had shrunk

I let the resin cure for 48 hours before stripping the heat-shrink tape and then lightly sanding it with 320 grit paper. I plan to just clear coat the repair with automotive clear coat, because the resin is known to be UV sensitive. 


The completed repair before clear coating. 

Postscript

Of course, the proof will be whether it survives being ridden..

Tuesday, September 5, 2023

2023 Vermont bike tour


Overall impressions

Very few breathtaking views presented themselves, but almost every minute of every day was tremendously scenic. Or maybe everything Vermont was just so green and beautiful that no low points existed to make beautiful parts seem spectacular.

The parade of tiny towns represented a dramatic contrast to Northern Virginia, with its year-on-year and fill-in development. Some population and geographic data really illustrate this conclusion. Essex County has fewer residents than my neighborhood in an area 1.5 times the size of all of Fairfax county.

No real low points really occurred. Day four was tiring, but not anywhere near the despair level. 
Population changes 1972-2021
County/State Area Population Population
mi^21972 2021
Vermont 9616 460K 646K
Fairfax County 406 454K 1.14M
Caledonia County 658 24K 30.5K
Essex County 675 5600 5900
Essex county peaked at 6500 in 2002

The Crew


Left to Right: Bill Erickson, Bill Luecke ("green bill"), Gil Menda, Vanessa McCaffery, Bob Nunnink, Ernie Bayles.

Tech

Bike


I used the same 40+ year-old racing frame with cantilever brakes that I have used on trips for the last decade. I was the only participant on cantilevers. Loaded, the bike was almost 50 lbs. 

I splurged for some "gravel-specific" Ortlieb Gravel-Pack front panniers so that I didn't have to pack everything waterproof bags. The front rack was also a new low-rider Axiom Journey DLX. The old rack made the panniers hit the arms of the cantilever brakes.
Gearing was  26-38-48 with an 8-speed 13-30. I used the 26/30 frequently. Because 8 and 9-speed cassettes are the same, a useful upgrade would be to go to 9-speed, which the 90's-vintage bar-end shifters could still handle it. For this trip, I removed the drop-out adjusting screws, which allowed me to squeeze in a 38 mm Specialized Trigger sport tire, albeit with only about 3-mm clearance to the chainstays. Broken spokes would be an existential threat.
Equipment upgrades for the future
  • Switch to a 9-speed 11-34 cassette.
  • Retape bars with double tape or silicone padding. 

Gear

Not including the bags, the gear plus Clif bars and Gu weighed about  18 lbs. I can't think of any way to reduce the weight without sacrificing important equipment. Fully loaded the bike came in at 50 lbs.

This time I remembered to bring a two-port charger.
I used every piece of gear I had in the bags.
I replaced my stinky, crusty moccasins with some ultralight Xero Z-trail sandals. They only weigh 284 g/pair, and they seem like you could walk some distance in them. The tread tended to pick up mud, though.

Gear limitations and replacements

Some gear should be added or replaced, including
  • a proper, consumer-grade, battery backup. The freebie I stole from Sandra would not charge my phone,
  • a free-standing tent with a proper fly. The amount of condensate on the flyless Sierra Design tent did not fill me with confidence that it would function in the rain,
  • a lightweight down jacket for mornings and evenings. The gray fleece I added at the last minute was barely enough.

Performance

The day-to-day performance degradation was not as severe as on the 2021 Catskills trip, but every day the maximum HR decreased. What would happen on a ten-day trip? I might be dead at the end...

Day HRmax Vmax Distance Elevation
bpm km/h km m
0 162 73.2 53.7 724
1 159 73.8 105.4 1084
2 156 68.2 93.4 1392
3 152 68.3 107.4 1325
4 146 67.8 115.6 1561
5 142 61 49.1 981

The camera doesn't lie: I've developed quite a beer gut this year...

Day-by-Day Reports

Day 0: Poultney, Vt to Poultney, Vt

After lunch we stopped at Poultney High School for a shakedown ride that was primarily characterized by map checks and wrong turns. After one long and wrong descent, we found Ames Hollow Rd,  our first Class 4 road. 

Vermont defines a Class 4 road as one that is not maintained by the town. This one was pretty much all rideable.  
We stayed at the Greensboro camp of Ernie's sister Jenny, which the family had built starting in about 1964, and now comprises several A-frames and a two-story house. 

Link: Day 0 Route

Day 1 Greensboro to Lake Carmi




We followed the Revolutionary-war Bayley-Hazen Road for much of the day, including a trip over Hazen's notch. The Bayley-Hazen road was the first road in northern Vermont. The route over the notch follows Vermont Rt 58, which is a dirt road. Amusingly, while I was waiting at the top, I chatted with a driver with New York license plates who stopped to complain that "How is this a dirt road!?" 
After Montgomery, we had a bit of dissent at the Longley bridge, and we bypassed the dirt road for a straight shot to the Missisquoi rail trail, the former Central Vermont RR,  in East Berkshire.
Dinner was at a food truck in Enosburg Falls.
I never felt terrible during the ride but I also never felt great. 
Campsite: Lake Carmi site 11 on the lake. 
Fun fact. Sometime between 1922 and 1926 Lake Carmi was upgraded from being named "Franklin Pond." 

Day 1 Route


Day 2 Lake Carmi to Newport



The US/Canada monument on Richford Slide Rd. We're in Canada now!



We headed out north from Lake Carmi, and then along the US/Canada border for most of the day. Some fraction of all the traffic we encountered comprised US Customs and Border Protection jeeps. We stopped for lunch in Richford, and then spent the next 1/2 hour riding back and forth on the two roads in Richford trying to find the proposed route. One consolation was the road fingernail clipper (#3 of 2023) I spotted on the second pass, although Vanessa got the quarter I passed twice.  In the end, we went down Corliss Rd, which unfortunately did not connect and had not connected for at fifty years. So it was back to Richford for the third time. 
On Richford Slide Rd we made a 300-yard detour into Canada when the road crossed the border and then reentered the US. The only indication was a 3-foot granite monument inscribed with Canada and United States. Apparently the border was a lot more chill in the past.
I perked up on the climb over the pass north of Jay Peak. Ice cream in North Troy also helped, but I was still glad to get to get to the Prouty Beach campground in Newport. Weirdly, we traded our reserved, expensive, not-ideal bare site with lake view for a less-expensive wooded site.
Dinner was at the only open restaurant in Newport. 

Day 3 Newport to John McGill's cabin in Victory


The Border Station in Beebe Plain (photo credit Bob Nunnink)



Our gracious host, John McGill ready to ride on Day 4

John's primitive cabin



Back in July, I had reached out to John McGill about routes in the NE kingdom. John and I had met twenty years before, mostly racing at Greenbelt Park in the middle of the week. He offered the use of his primitive cabin at his camp on Victory Hill. It was a bit of an unknown--we only had some interior photos to judge. John created and administers a private foundation mountain bike trail system, which was just adjacent to his cabin. He also suggested some routes to the east of Victory Hill. 

The day started with a bit of chaos, as some wanted to stop at the Wendy's for breakfast sausage and more coffee. Apparently only the drive-through was open, but that situation was not obvious for almost twenty minutes. Only Bill E. and Gil managed to activate the sensor and order. I just jammed down a Clif bar. I suppose that this staffing problem is part of the "great resignation." None of the delay really bothered me, which I think is a good sign of my much-more-chill outlook on time and dates.

We rode north out of Newport on the Newport-Derby rail trail that was part of the Boston and Maine RR, to Derby.

I didn't realize that once we left the trail for the road that we were only a few hundred yards from the Canadian border. and the
border station. 

The border station in Beebe Plain  was also curious. Getting in to the US was like going through the Wendy's drive-through, but the way out of the US was blocked by a drop-down metal security barricade. I wanted to take some pictures, but thought that it would just get me in trouble. The postoffice lady yelled at me for blocking the ramp, as if I couldn't figure out how to get out of the way.  A post-ride map check showed that all the houses whose driveway onto  "Rue Canusa" in Canada are all actually in the US, and the border goes down the middle of the road, but on the other side of the border station.

On Derby Line Rd I managed to run into Bob while trying to steer around him.  Shortly after Bob and Vanessa took the Vt highway 111 route to Morgan, and the rest of us took the dirt Town highway 38. they saw a bear. We saw a lot of Vermont dirt road. We resupplied at the Morgan Country Store, where Fox news was playing, and the cashier seemed a bit surly. Found $0.01 in the parking lot!

Lunch was in Island Pond from the supermarket. Because we were unsure about the exact situation at John McGill's cabin, we stocked up assuming that there would be no resupply until Thursday night. The planned route included a climb up Radar Rd followed by a descent to Gallup Mills. The Radar Rd, which we would briefly use the next day, goes to an abandoned Cold-Ware distant-early-warning radar site on the top of East Mountain. We chose to stick to the paved road, because the climb on Victory Rd
was only 300 m (vs. 400 m) in about 1.5 km less. And Victory Rd was challenging enough. 

The last ten miles on River Rd was quite scenic, with views of Umpire and Burke Mountains, and the wetlands along the river. After a short climb up Victory Hill Rd, I sorted out where to find John's caretaker, who said "Oh, he's there, just go to the end of the road and through the gate." I found John's car, complete with bikes, but no sign of him. He arrived later, on his mountain bike with a brush lopper in his backpack--trail maintenance. He had also dropped off some corn and bread, and provided burgers as well! 

Links: 
Victory Hill Trail Club: https://victoryhillmtb.com/

Day 4 Victory Hill to Victory Hill to Lyndonville




The Ithaca contingent's friend Cory Baclawski, would would be hosting us at his house at the end of the day, came to ride with us. He brought his friend Ben Deede, who had taken the day off work joined us. Ben actually knew the route and provided expert guide services.  John McGill rode with us until we reached Paul Stream Rd route through the logging area by Mitchell Mountain.

We cached the bags at the start, and would return to collect them later. 

We backtracked the end of the day before, north on River Rd, and then took the Radar Rd north before turning off onto a side ride. The west-to-east transit of the logging area was on absolutely pristine roads. It was hard to understand how they stayed so perfect--the brush was all pushed back, indicating that they were routinely used, but the clay surface was smoother than pavement.

I was fading by the lunch stop, and the 1-km bushwhacking on Hall Rd made me nervous--nothing in the tank. We turned west off North Rd and went through two gates onto a two-track that wound through the bogs. I was really confused about our location, and was really flagging, even though I had strictly stuck to eating something every hour. A push on a recently regraded and repair stretch of Paul Stream Rd really demoralized me. But shortly after I found a second wind, and got rolling again. We recovered the bags at John's cabin, and recovered Ernie, who had inexplicably turned on Masten Rd instead of following the road back to the cabin. Cory took all the gear in his van, so we had the whole day unloaded. 

The ride over Kirby Mtn Road was steep and hard, but I felt fine. On the descent I foolishly tried to follow Vanessa, who had a head start, but I took two serious hits in a row, which shook my confidence, so I backed off. I was completely dead by the time we got to the end at Cory and Lisa's house. Two beers didn't really help the alertness, but were very welcome anyway. I nearly fell off Cory's deck when I leaned against the railing and it cracked. Much bouncing of small children occurred. Their oldest, Silas,  and I spent some time trying to re-sort his rock collection, which tickled all of my organization needs. It seemed very similar to one that I had 55 years ago, though his had twice as many specimens. 

Sleeping indoors got us out of the overnight rain.

Day 4 Route

Day 5 Lyndonville to Greensboro


Staging in the drizzle. Photo credit Bill Erickson


Walden Mtn Rd. Impassible without pushing.

Top of the Mountain Farm Stand. Breakfast sandwiches in the clouds.

The forecast was for 60F and rain, and we left in the rain. We passed "Vermont's largest corn maze" on Burroughs Rd. The thin, wet layer of mud really sucked at the wheels, and I was glad that we were chopping off the southern half of the planned ride. On Walden Mountain Rd, Ernie chatted up a crusty old local (COL) for intel on the pass. He opined that we would be pushing, which just sounded like
a challenge to me. But COL was correct, and about ten minutes of pushing followed, on a class 4 road that had been destroyed in the flooding in June--it was basically a stream.

After a rolling bit on a barely drivable road, Top of the Mountain Vegetable Farm appeared out of the cloud: coffee, sandwiches, pet goats.

After that it was a quick run through Greensboro Bend and on to Greensboro, where Jenny treated us to killer tacos and wine.

Sandwich report

Our 2021 Catskills trip included some  of the best sandwiches I have eaten. This trip was notable for my poor choices. I should have followed the lead of Bob "The Sandwich Whisperer" Nunnink, who apparently enjoyed his.
  • Day 0 Mandy's Pizza and subs, Hudson Falls, NY: uninspired meatball parm
  • Day 1 Parkside Grill (Food truck) in Enosburg Falls: two hotdogs that had still be in the fryer, even though I wasn't excited about that
  • Day 2 Italian sub Main St. market in Richford. High point, but really only acceptable. 
  • Day 3-5 No sandwiches.