This is what's right with The Industry®
- Thread starter Jm_
- Start date
Excellent point. I was thinking of aluminium rims all this time. But since just a few crab0nz rimz have molded spoke/valve holes, I have to admit I'm not intimidated by thinking of taking my old, trusty 8mm bit to any of them.
i've talked to a buddy who is in the carbon industry, his general advice for drilling it is "don't". at least not with a regular drill and bit.
People cut carbon steerers all the time.
The only issue I can see is the exposed carbon fiber strands that you'd want to somehow protect or re-paint over, because they can cause corrosion if in contact with aluminum, like the valves.
I mean, are we saying that you can't cut a carbon steerer either?
Lots of people seem to be doing it for droppers and the only issue seems to be a few companies say "don't do it, that area is not reinforced to support a hole", well, there's already a hole where your presta valve is. I do recall a slightly different drill bit, but otherwise can't imagine this is a big deal.
The carbon layup may well be reinforced in that area. Drilling it will change the stress riser locations and severity.
They sure as hell didn't run any stress analysis with extra custom drilling going on. So will it break? I dunno, but it's not designed to work that way...... Then again I never drilled speed holes in my old Kona rocker links so I'm a bit of a sissy.
Some rims have molded holes, I would not even think about drilling those.
Indeed. But most of the stuff out there is drilled from the factory. And I'm pretty sure they don't use any NASA leftover robot for that.
Maybe not NASA, but the equipment they're using is sure as shit designed for the job, and isn't the kind of equipment your average ham fisted mountain biker has access to.
Just read the link for this in a PB article, then told my family they should buy it for wifey for festivus.
https://www.hurlyburlybook.com/
https://www.hurlyburlybook.com/
This is a small thing, but I've always liked EBC brake pads. Now that I'm back on Avids, who wants a lotta money for pads, I've been buying EBC Reds again. They are not the easiest to find, but I pleasantly discovered that the US distributor will ship them for free via Fedex Ground!
https://perfectbrakes.com
I just got 2 sets delivered in 2 days for $30.
https://perfectbrakes.com
I just got 2 sets delivered in 2 days for $30.
How do they go in the wet? I haven't run EBC Reds in years and can't remember muddy racing with them. I know they were great in the dry.
Really? Simple Brad-point bits that any decent woodworker has a drawer full of?
Wow - I'm impressed.
I figured it would be some titanium / unobtanium wonder bit only available from a small Japanese man working a coal forge in Scandinavia and priced at a measly 9 billion slotniks each.
Wow - I'm impressed.
I figured it would be some titanium / unobtanium wonder bit only available from a small Japanese man working a coal forge in Scandinavia and priced at a measly 9 billion slotniks each.
Thanks. I drill two or four 1/16" drain holes in all my carbon rims so I'll get that carbon specific bit.
No failures after many years and many many rims using the most basic Dewalt bits.
Your wood bits are high speed steel perhaps? Titanium nitride coated? About $6-7 bucks for a 1/4" diameter? This is solid carbide - pretty expensive - around $45 for the 1/4" diameter size. So not quite the same, but as per Lljt's experience, yours would probably function to cut carbon, and probably better than a traditional point.Really? Simple Brad-point bits that any decent woodworker has a drawer full of?
Wow - I'm impressed.
I figured it would be some titanium / unobtanium wonder bit only available from a small Japanese man working a coal forge in Scandinavia and priced at a measly 9 billion slotniks each.
I won't say either way about drilling holes in rims or not, I think there are a lot of factors to that question. I'll concede to the conclusion of the person who has the biggest data set to draw from. Or a lizard that could tell us the factory designed failure characteristics of a given rim at the valve hole. I drilled aluminum when I was younger and lighter without any issues or dependents. Never tried it on carbon at 240 present weight and family status. Theoretically a molded hole is much stronger than a drilled hole, because the continuity of the fiber is preserved. I've used simple west-system marine epoxy as well as the depot's finest for various fishing rod building type activities, and a little bit of that would seal any dry fibers.
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Cobalt.
I was a toolroom machinist in a past life, so don't play with cheap tooling. Just not worth it to drill 3 holes then have to head to the grinder to sharpen (wish I could sharpen Brad or Forstner bits at home)
Whilst not carbide, it should do the job. Not that I would drill out a molded hole.
Just commenting on the bit. Really was expecting something closer to a fine toothed diamond ceramic hole saw style bit.
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ethically sourced cobalt?
free range organic.
*"No steroids were used in the sourcing of this cobalt"
Of course.
Do you really think I would use Cobalt of a questionable source to salt my thermonuclear weapons?
Geez, some people.
cruelty free grass fed cobalt.
Yes, I was very happy to receive that email and see that I don't have to give up a week of prime riding in the middle of September anymore.
Given my adventures with this in the airport:
I have taken it upon myself to improve on it. I can literally zoom through the airport at break-neck speeds on this knee-scooter, it's freaking amazing. It's a bit unstable though due to the construction and geometry and could definitely be improved. I'm thinking something like this:
And we could probably do a $200 version without the carbonz.
I have taken it upon myself to improve on it. I can literally zoom through the airport at break-neck speeds on this knee-scooter, it's freaking amazing. It's a bit unstable though due to the construction and geometry and could definitely be improved. I'm thinking something like this:
And we could probably do a $200 version without the carbonz.
Could be slacker. And root-beer.