|
|
Thread Tools | Display Modes |
#181
|
|||
|
|||
I am that out of date
On 4/29/2021 12:53 PM, wrote:
On Wednesday, April 28, 2021 at 8:01:42 PM UTC-4, wrote: The meterial is: Zinc Yellow-Chromate Plated Steel which is not compatible with carbon fiber. If you ever switch to carbon fiber cranks, you'll have problems. I suggest you stick with stainless steel washers. What is it about zinc plated steel that makes it incompatible with CF? Possible galvanic corrosion. -- Andrew Muzi www.yellowjersey.org/ Open every day since 1 April, 1971 |
Ads |
#182
|
|||
|
|||
I am that out of date
On Thursday, April 29, 2021 at 4:32:12 PM UTC-4, wrote:
On Thu, 29 Apr 2021 10:53:34 -0700 (PDT), " wrote: On Wednesday, April 28, 2021 at 8:01:42 PM UTC-4, wrote: The meterial is: Zinc Yellow-Chromate Plated Steel which is not compatible with carbon fiber. If you ever switch to carbon fiber cranks, you'll have problems. I suggest you stick with stainless steel washers. What is it about zinc plated steel that makes it incompatible with CF? Radically different galvanic potential voltage in the presence of an electrolyte. https://l-36.com/corrosion.php Note that zinc is very anodic (-1.0V) while carbon is very cathodic (+0.2V). Remember the carbon-zinc 1.5v flashlight batteries?[1] If you look at the chart, the materials that are close together in the galvanic series are fairly immune to corrosion while the materials that are far apart are a problem. For example, carbon, titanium, and stainless steel are fairly close together and therefore safe. However, aluminum, copper, brass, cadmium and zinc are at the opposite end from carbon and therefore need to be insulated from the carbon. Painting the CF with an insulator can work but only until a tiny crack ruins your day. This is aluminum and CF (nobody makes zinc galvanized bicycle frames) which should give you a clue what can happen: https://www.bikeforums.net/road-cycling/992139-colnago-c40-carbon-fiber-corrosion-aluminum-guides-salt.html Dr Barry L. Ornitz on galvanic corrosion: https://yarchive.net/electr/galvanic_corrosion.html "How to prevent galvanic corrosion in carbon composites" https://www.youtube.com/watch?v=DPbToNbtubg (5:04) I never studied metallurgy but recalling my physics classes it all makes sense. But gawd that video was painful. This one is much better https://www.youtube.com/watch?v=yRpMZaU8zKw [1] Yes, you can make a carbon fiber battery: https://newatlas.com/energy/carbon-fiber-structural-battery/ -- Jeff Liebermann PO Box 272 http://www.LearnByDestroying.com Ben Lomond CA 95005-0272 Skype: JeffLiebermann AE6KS 831-336-2558 |
#183
|
|||
|
|||
I am that out of date
On Thursday, April 29, 2021 at 1:37:11 PM UTC-7, AMuzi wrote:
On 4/29/2021 12:53 PM, wrote: On Wednesday, April 28, 2021 at 8:01:42 PM UTC-4, wrote: The meterial is: Zinc Yellow-Chromate Plated Steel which is not compatible with carbon fiber. If you ever switch to carbon fiber cranks, you'll have problems. I suggest you stick with stainless steel washers. What is it about zinc plated steel that makes it incompatible with CF? Possible galvanic corrosion. The corrosion that was on the C40 was probably someone running out of the proper pop-rivet and using a couple steel ones The top cable ends on a bike of that vintage were chromed bronze and the cables themselves high grade stainless. |
#184
|
|||
|
|||
I am that out of date
On 4/29/2021 10:51 AM, wrote:
On Wednesday, April 28, 2021 at 6:38:21 PM UTC-4, Frank Krygowski wrote: On 4/28/2021 4:22 PM, jbeattie wrote: I've gotten pedal washers free from LBSs and bought a bunch off Amazon. I can't find any hardware store equivalents. If there is a cheap equivalent/common part, let me know. These might do: https://www.mcmaster.com/standard-wa...teel/od~0-734/ and be cheap enough. Not as cheap as some on Ebay, though. I don't know about shipping. I'm lucky in that McMaster-Carr's warehouse is within a couple miles of a route I drive weekly. I've ordered stuff and picked it up myself. -- - Frank Krygowski McMsters shipping is top-notch. Usually next day and usually free. We regularly order from mcmaster at work, and I've used them almost exclusively for hardware for well over 20 years. Never had an issue with shipping, though once or twice I've had a quality issue with the product and the fact that they usually don't list the manufacturer of the product is annoying. Miss those big yellow McMaster-Carr catalogs! We have a great fastener store in Sunnyvale, Olander, that does will-call. A few years back they instituted a $5 minimum per SKU because they were getting tired of selling 25ΒΆ items to end-users. https://www.olander.com/. But if you're in no rush, you have a much wider variety of metric fasteners on Aliexpress. |
Thread Tools | |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
What date is it? | lardyninja | UK | 5 | April 3rd 09 06:46 PM |
need a date look here | Donald Munro | Racing | 0 | May 27th 06 11:21 AM |
need a date look here | Donald Munro | Racing | 0 | May 27th 06 11:16 AM |
need a date look here | Donald Munro | Racing | 0 | May 27th 06 11:15 AM |
Perfect date | Claire Petersky | General | 19 | April 15th 05 03:55 PM |