Entries Tagged 'Cool Stuff' ↓

Our stable

2011 Gazelle NY Cab

Trek 7200

Gazelle Miss Grace

BTwin 3 Original

We each have two bikes.  Mine is the Gazelle New York Cab Edition, and K has the Miss Grace.  I also have a 2000 Trek 7200, and my wife has the very basic BTwin 3 Original.

My Trek has been the backup bike, but I also use it for running into work on my days off.  Most days, I use the Gazelle to commute to and from work.  It’s just so much easier to use.   My wife rarely uses her Gazelle, as it’s slightly too large for her.  She takes the BTwin into Mons for French classes three days a week.  If someone steals her BTwin, I’m not out much.  We’ll probably sell her Gazelle next spring, since she so rarely uses it.  Pity.

How to shift speeds on a bicycle without gears.

What are you riding?  Who uses gears any more?

I bought this bike last January:

2010 Gazelle NY Cab

2010 Gazelle NY Cab

It’s the New York Cab model from Gazelle, in the Netherlands.  As pictured here, it comes with a Shimano Nexus Inter 3 three speed  internal hub transmission.  Smooth to operate, but not enough range between the low gear and the high gear.  As built, the sprocket ratio between the front and rear sprockets gives a nice top gear, but the low gear isn’t low enough to take this heavy bicycle up much of a hill.  As it turns out, I have a fairly significant 500 meter long hill just before I get to work.  So, the gearing on this thing just wasn’t up to it.  My legs got strong enough to push it up that hill, but not without considerable body heat build up.  Not how I want to start my work day, since I ride in my work clothes.

A colleague told me about the Nuvinci transmission.  I don’t know where he learned of it.  It’s the Nuvinci model N360, from Fallbrook Technologies.  It has a 350% difference between it’s lowest and highest input/output ratios.  No gears.  It’s a continuously variable planetary transmission that uses steel balls instead of different sized gears:

As you can see, by changing the angle of the balls’ axles, it changes the size of the track on which the input and output discs ride.  It’s continuously variable between its highest and lowest ratios.  To the rider, this means you can dial up the precise gear ratio you want for a particular load to stay at the exact tempo you desire.  You always have the right “gear” available to you.

My first task was to get the Shimano OEM hub transmission replaced by the N360.  I didn’t attempt this myself.  I’d read tons about bicycle wheel building online.  But, I’ve never built one from scratch.  Realizing my limits, I brought my wheel to my local bike shop, along with the N360 in its box, to have their wheel builder do his magic.  A couple weeks and EUR 50 later, I had my wheel with the N360 laced into it, ready to install.

You’d think it would be easy from this point.  You’d think.  The nineteen tooth cog the mechanic at the bike shop gave me had the wrong spline pattern, and it was the wrong thickness.  So, I ordered a twenty tooth Surly single speed cog from the internet.  This was when I also realized the cog on my three speed Shimano transmission was for 1/8″ chain.  The N360 requires 3/32″ chain.  I needed a new chain.  I also thought I’d need to change the front chain ring.  But, on inspection, it turned out that Gazelle has installed a chain ring for 3/32″ chain, and was running 1/8″ chain on it to use that Shimano transmission.  Result!  I didn’t have to change the front chain ring!

Removing the old 1/8″ chain with the chain tool that came with a patch kit I bought many years ago showed me why that chain tool was included in a cheap patch kit.  It was nearly worthless.  It worked once, to remove the old chain.  I bought a new Park Tools CT-5 Mini Chain Brute chain tool.  You want to get yourself one of these.  Very nice.  Compact.  Worked perfectly.

While waiting for internet delivery of those parts, I had time to route the Bowden cable housings through the bike’s frame and mount the controller on the handlebar.  Fishing the cable housing from the down tube opening at the bottom bracket housing took some fiddling, but I got that job done in a couple hours.

Nuvinci N360 controller

Nuvinci N360 controller

Since there are no discrete gears to select on this transmission, it didn’t make sense to use a numerical selector, I’m guessing.  Instead, the guys at Nuvinci developed this little controller, that shows a little bicycle on a ribbon that flexes up to a steep hill (underdrive), or straightens out to a flat road for the little bike to ride on (overdrive).  In actual use, I don’t really pay much attention to the indicator on the controller.  I just adjust it by feel.

Well, the goodies arrived from the internet, and here are the few pictures I took of my installation.

Here is the N360 installed, with the chain, but without the chain case or the control cables:

Nuvinci N360 installed, bare

Nuvinci N360 installed, bare

It took me a couple hours of whittling and adjusting of mounts to get that chain case to fit without rubbing on either the hub or the chain itself.  But, I was able to fit it.  Just.

Nuvinci N360 installed, with chain case, sans cables

Nuvinci N360 installed, with chain case, sans cables

I think I cut a little more clearance for the hub interface than I may have needed.  But, it wasn’t easy to guess how much clearance I’d need.  I’m pleased with the results.  Notice the control cables still not cut to length or secured.  You can bet I paid very, very close attention indeed to the installations instructions when it came to cutting those control cables to length and attaching the cable ends.  I measured three, four, five times.  Then did it again.  Made sure I was measuring the correct cable (under drive or overdrive cable).  I used a drinking straw that I had split lengthwise and cut to the correct lengths to set the cable ends properly.  All that measuring paid off.  Cutting off the excess cable is when you commit.  It was perfect.

Here it is, installation complete:

Nuvinci N360 installed, complete

Nuvinci N360 installed, complete

The only two minor problems I had to resolve after a few test drives was to tighten the spokes on that wheel a quarter turn on each spoke.  They weren’t quite tight enough, and there was some spoke noise when I put my son’s seat on the back and took him for a ride.  I also needed to turn the overdrive cable adjuster on the controller out two turns to take up the slack with the controller to allow me to select full overdrive.

After two weeks use, I did find that the spring tab on one of the cable ends at the hub interface was just close enough to the chain to rub on the chain rivets if I put pressure on the controller in the overdrive direction.  I fixed it by grinding off about a millimeter of steel from the side of that spring tab that was close to the chain.  Noise gone during upshifts.

I find that this hub does not really allow upshifting under full load.  It does allow downshifting under load, though.  It is possible to shift it up while under load, but since there are no gears, what I find it does is work it’s way up to higher ratios in between power pulses while pedaling as long as I am putting pressure on the controller to shift in that direction.  Very, very smooth.  Just like everyone says.

That hill just before work is now trivial.  In fact, I may have erred on the side of too low of a ratio with my twenty tooth rear cog selection.  The front chain ring is 38 teeth, the OEM cog on that Shimano transmission was a seventeen tooth.  I wanted to be sure my lowest gear would make that hill simple.  I achieved that.  I could probably do with an eighteen tooth rear cog.  But, as it is a heavy bicycle, and I have cargo racks front and rear, there will be days when I have quite a load on it.  That nice low gear is very useful for these times.

Since I’ve been riding my bike to work, 17 kilometers each day, I’ve lost twenty pounds of fat.  So, the extra pound of weight from the N360 is more than compensated for.  Even so, the extra weight of that hub amounted to less than one percent of my rolling weight (the bike, plus me, plus cargo).  Insignificant.

If you don’t have one of these, I recommend one highly.  Very highly.

Don’t those hones just drive me nuts.

I thought I’d try to lap my ceramic hones in a criss-cross pattern with my diamond plate.  And sure enough, they remove steel much better than when they were lapped with just a linear stroke down the long axis.

I’m pretty sure I just made some deep ditches where honing debris can collect, keeping the honing surface clean and biting well.  My evidence for that is how quickly after cleaning the hones with scouring powder (before I criss-cross lapped them), they would feel glazed over and stop biting into the razor.

The shave results are dramatically improved.  I’m quite pleased with the sharpness and smoothness I’ve achieved from my razor.  I shave with it once a week on whatever weekend day I decide to shave.  I tend to give my face a day off once a week.  I haven’t cut myself with that straight razor yet.  But, my technique is still clumsy, and I’m ultra careful, as you’d expect.

It is satisfying to be able to develop a shave worthy edge and use it successfully.

Ceramic hones’ “grit”

All right.  Back to the straight razor honing problem.

I’d read on a few forums how important it is to have the hones flat. I mean flat.  I can say for sure the fine and ultra-fine ceramic hones I got from Spyderco are NOT flat.  How do I know?  It’s easy to see the high spots by where the dark lines form (the ceramic is white) from where the hone is removing steel from the blade.  Not only that, I can both feel and hear that the edge is not in full contact with the hone.

Well, I have a dual grit (400/600) diamond hone I got from EZE Lap.  So, I went after my ceramic hones with the 400 grit side of that diamond hone.  I put plenty of water on the diamond plate, and wore away the ceramic hones on it until the entire face was new, clean, ceramic.  The medium grit ceramic took only a few minutes.  The ultra-fine hone took about 15 minutes.  But that fine grit ceramic hone took an hour of pretty vigorous lapping to get a fresh, flat, surface on it.

The difference in the way they hone is shocking.  The edge of the razor is in full contact with the entire face of the hone over the entire stroke.  Steel is deposited on the hones in a uniform grey pattern across the face.  No high spots.

BUT, a guy on a straight razor forum tells me now that by lapping the ceramic hones, I’ve changed it’s apparent grit.  He said that the factory uses the same grit alumina (synthetic sapphire) in the ceramic medium for both the fine and the ultra-fine hones, and it is the surface finish of the hones that determine their apparent grit.

I’m dubious about that.  Here’s why.  If you have a very fine grain medium (ceramic) in which is embedded a particular size of abrasive grit, that abrasive grit is going to scratch metal based on it’s size.  Obviously.  There is no way I can think of that will make it coarser.  For example, if you were to use an insanely coarse lapping plate and dig gigantic scratches into that ceramic surface, you’d be left with islands of ceramic with the same abrasive grit in it.  There’s be room in those gigantic scratches for honing debris, which may actually make the hone produce a smoother edge bevel.

This theory works if, and only if, the finished ceramic hone is indeed a more or less amorphous solid with alumina particles of a particular grit size embedded into it, and it is those alumina particles that actually abrade steel away.

It might be different if the ceramic is so fine grained and hard that the finish cut into it by various grit diamonds may very well determine how smooth the face of the ceramic is, and therefore, it’s apparent grit size.

Does anyone have any better knowledge of this?  Or perhaps an idea how I could test it?

Blade safes

So, what does one do with their used double edged razor blades?  It’s hardly safe or wise to simply toss them in the trash.  Those things are still insanely sharp.  They’ll cut their way out of a trash bag and into the hand of whomever is handling it.  After being in contact with everything else in a bathroom trash can.  Not to mention the dangers if there are children in the house.  Used razor blades are not something you want a child to play with.  Then, there are also the trash men to consider.  Their job is tough enough without having to worry about cuts from household trash.

The answer is to use a blade safe or a blade bank.  A container to put the used blades into.  One that the blades cannot get out of, and that kids cannot get into (without tools, anyway).  I don’t know about now, but medicine cabinets used to have a small slot in the back into which you could put used blades.  They would just fall into the wallspace between the studs.  The house wouldn’t live long enough for it to fill up.

An interesting note about that.  While I was attending some school or other at Keesler AFB, in Biloxi, Mississippi in the 1990s, they were demolishing old dormitories that had been there since the 1940s.  I walked through the bulldozed wreckage, poking around, and I ran into mounds and mounds of used double edge razor blades.  Those little slots had been used by tens of thousands of airmen through the years.  Mostly clumps of congealed rust, some of them were not.  It was an interesting find.

I had a couple commercial blade banks.  One, I bought for a buck when I bought my first double edge shaving setup.  The other was sent to me as a freebie in an order for some shaving soaps and blades from Bullgoose shaving.  Phil, the proprietor, is very, very prompt in shipping, and has always included a sample of something or other in my orders.

I don’t know what prompted me, but I was curious how secure the commercial safe was.  That slot is pretty wide and is the length of the can.  I had about 40 blades in it.  I found I could simply shake out the blades.  That was a little alarming.  I have it so high up in my bathroom, my boys can’t reach it easily.  But, they are clever little devils.  It’s only a matter of time.  So, I set about making a more secure blades safe.

I used a small tomato sauce can.  I took an old chef’s knife and simply punched a slot in the top of the can, punched a small hole in the bottom of the can to relieve the vacuum, and shook out the tomato sauce.  I suppose any small can of whatever will pour out of the slot would do.  I rinsed out the can, and since we had just used the oven, I popped it into the oven to roast out the few drops of water that didn’t shake out.

Here they are, side by side:

Blade safes

Blade safes

Blade safes

Blade safes

As you can see, the slot I punched into the tomato sauce can is a lot narrower and shorter than the slot in the commercial blade safe.  Both slots have a small lip turned towards the inside of the can.  I put all my blades into the new blade safe I just made and tried to get one out.  No joy.  This was the result I was looking for.

When this can is full, I’ll just drop it into my metal recycling and it will get melted down with all the other steel cans.

I suppose there are some places that may require putting used blades into a sharps container, such as what would be used for needles.  I’d probably cheat, and still do what I’m doing, just to return that steel to use instead of it being incinerated as medical waste.  Either way, we’re not talking about a lot of steel.  I read on a bulk blade sale once that a thousand double edge blades weigh about 8 ounces, or about 225 grams.  If you use a hundred blades in a year, that’s less than a whopping ounce of steel.  A big soup can weighs more than that.

So for me, the goal is safety, not so much ecology.  Though, the ecology of recycling the steel is a side benefit.

Honing that straight razor.

The Spyderco ceramic stones arrived last week.  Here’s a great photo (used with permission) by Maximilian (who has a great site of straight razors, etc), of the razor I have, a Dovo Special 5/8 in with faux tortoise shell scales:

My first attempt at honing it was not successful.  There are all kinds of tests you can do to test the edge at each stage of honing.  Sure.  Like I know what each is supposed to feel like.

For example, there’s the thumbnail test, commonly abbreviated TNT on the shaving forums’ honing sections.  Apparently, the trick is to pull the edge over the back of your wetted thumbnail, and it’s supposed to feel like something or other.  Here’s the thing, do that to a shave ready razor, and it’s no longer shave ready.  So, what should it feel like at the successful completion of setting the bevel, for example?  Who knows?

There’s another one called the thumb pad test.  Guess how that’s abbreviated?  Anyway, this one is done by seeing what it feels like when the edge actually slices into the outer layers of the skin on the pad of your thumb.  Again, who knows what this should really feel like?

After my first honing, I tried to shave with it, and it wasn’t anywhere near sharp enough.  It shouldn’t hurt to shave.  So, I had a try to look at the edge itself under my stereo microscope at 30X magnification.  The edge of a sharp razor should be far beyond the resolution of that microscope, so should have been completely invisible.  And, it was.  Almost.  There were two areas were I could see light reflecting off of the edge where the bevels didn’t quite meet.

So, I had a second go at it.  This time, using as light a touch as I could, and very careful, deliberate, strokes on the stones.  I didn’t try to look at the results again, but tried a shave with it.

I got a shave from it.  Not a great shave, but not a painful one, either.  Still room for improvement.  I’m still not convinced the first stage edge is set quite right.

The thing is, the coarsest Spyderco is graded medium.  For an undamaged razor, that is probably just fine.  Mine was seriously abused and the edge was quite damaged (what the hell did I know about stropping a razor in 1994?).  So, I ordered an EZE Lap dual grit 3″ x 8″ diamond hone to use to set the initial bevel quickly and accurately.  I’ve already got an hour of honing on that Spyderco Medium, and it still isn’t right.

I’ll try again in a week or two when that new diamond hone arrives.

Looking over Maximilian’s page, I see he has links to a series of honing clinic videos on the bottom of the page.  Looks like I have some homework before my diamond hone arrives.

Speaking of razors…

I thought I’d have a go at making a double edge razor handle.  Not too hard at all.  And, it turned out surprisingly well, I think.  It’s crafted of the finest European chestnut, with a hand rubbed oil finish.  Only the finest brass and steel hardware secure the blade to the handle.

Chestnut razor

Chestnut razor

Chestnut razor

Chestnut razor

Chestnut razor

Chestnut razor

Chestnut razor

Chestnut razor

Chestnut razor

Chestnut razor

It’s not as heavy as my Pils stainless or my Feather All Stainless, or my Merkur Futur, or any razor for that matter.  The balance is pretty good, but it favors the handle.  The blade angle is quite nice, though this razor is a little more aggressive than most people are looking for.  Changing blades can be a bit of a trick and requires a screwdriver.

How does one hone a straight razor?

I read a thread about the magnification required to inspect an edge being honed, and a pretty authoritative answer was that 35X will reveal everything necessary.  Convenient, since I happen to have a 10x/35X stereo microscope.  But, the microscope was fitted with 110V/60Hz fluorescent lighting.  The problem was in the reactance ballasts, of course.  They were designed to operate at 60Hz, and run far too hot at 50Hz.  So, I replaced the sockets and lamps with locally available CFL lamps with built in electronic ballasts.

Now, with the appropriate inspection tool, I tried out my straight razor honing on a razor edge systems ultra fine stone, just to test the effect on the bevel and to see how visible the changes were.  Clearly, the wrong hone for the job.  So, I ordered a set of three ceramic Spyderco hones to do a proper job.

I hope I can get a nice edge with the new stones.

Omega X-33

Mystery Gillette Razor

I got this on ebay for a buck.  The sale said it is a ladies’ travel razor.  No model number, though.  The pouch for it is pretty lame.

The manufacturing date code of J4 decodes to the fourth quarter of 1964, I think.

Update:  It turns out this is called a Travel Tech razor.

The thing is, there’s no place now you can actually have fucking blades where you might actually use a travel razor in a tiny sink say, on an airplane.  Which is probably why I got this for a buck.