MattyCiii's third build

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MattyCiii's third build

Post by MattyCiii » May 07, 2013 7:17 pm

If you're like me, you have no problem finishing the sentence "For my next build, I plan to..."
Well, this is the build thread for my third bike.

The core of the bike is a collaboration on design and build of a "common power module" with ES member 900Steve. That's the subject of another thread. I think it will generate a lot of interest. This thread is dedicated to the overall bike that will share that common power module - the story of what I build off a shared/common platform. So here goes:

Primary Objective: The ultimate utility bike. By that I mean a city commuter and grocery getter.

User Requirements: These are the non negotiable attributes of the build:

1. It will be a folding bike. Since I moved, I don't use the "folding" capabilities of my Dahon Jetstream "F3" Folding Bike much anymore. But it's irreplaceable when it's needed. For a little added complexity and weight I gain so much utility. This is a no-brainer.

2. It will be rideable as "pedal only" without too much trouble. WTF does that mean? I've ridden my A-line ~10 miles pedal only in one sitting. And I've ridden it up "the big hill" I live on (albeit at about 0.5mph, and nearly passed out when I arrived). But its not something one would seriously ride without electric propulsion. In contrast, my folding bike is only slightly heavier and has slightly more friction as pedal-only with electrics installed as it did when it was "just a bike". In this sense, my third bike must be more like the Dahon than the A-Line.

3. It will fit on a bus rack. Pretty damn specific for a non-negotiable, fundamental User Requirement. But there have been a few occasions where I've needed to load the folder onto a bus rack. The A-Line in contrast literally won't fit (and if it did, it's so heavy I'd be afraid the bike shear the rack right off the front of the bus :oops: ). So, there it is - it must fit on a bus rack.

4. I will keep weight and complexity away from the wheels. My "simple wheels" User Requirement is to keep expensive/heavy/complex things away from the wheels and move them somewhere else (to the middle of the bike). This in turn should mean less expensive wheels - easier to justify having a spare pair on the shelf (for dings, crashes, etc, or for studded snow tires, knobbies, etc.) It will also mean less unsprung mass for better suspension response and less rotational inertia for slightly better acceleration and slightly less wear & tear on the drive chain.

More to follow. If I make changes or additions to these criteria, I will edit them inline but note them below:
-----------------------------------------------------
Changes:
7 May 2013: Added link to the build thread for the common power module in the second paragraph.
9 May 2013: Edited User Requirement #4 above to be more succinct.
15 September 2013: Replaced "Constraint" with "User Requirement", reflecting lingo from a systems engineering class I'm taking.
Last edited by MattyCiii on Jul 02, 2017 1:47 pm, edited 6 times in total.
1st build: Dahon Jetstream folding bike. Quick, reliable, capable of 32mph. Light enough to lift, folds for easy transport by car/bus/train.
2nd build: RC powered 2009 Norco A-Line. Top speed 39mph. Built like a tank, it's resistant to Boston potholes, can stop on a dime, easily goes up/down curbs when necessary.
3rd build (just started): Scratch build ultimate utility bike. Based on a common power module using a NuVinci left side freewheel.

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Re: MattyCiii's third build

Post by MattyCiii » May 07, 2013 7:36 pm

Major Goals of this build: Major goals are negotiable, but highly desirable. They are often derivative of the User Requirements already listed above.

1. The bike must be easy to service. Some parts wear out. These must be easy to access and replace.

2. The bike must be tough. To quote Farfle: "Build to last..." My A-Line is insanely over-designed for its purpose, My folding bike is under built for the torture I inflict on it. This bike will be a tough bike, somewhere in the middle of the two.

3. Minimize Custom Parts. Electric bikes are the perfect thing for me. I love the challenge, the Zen and the Art of E-Bike Maintenance, and the thrill of the ride. I've made custom parts with hammer and hacksaw, high-tech outsourcing, and with the help of 900Steve, lathe and mill. It's really, really fun. But, what do I want to do with the next 2 years of my free time? I'd rather devote 6 months to the build and be riding the other 18 months than do 23 months of machining and ride for 1. Some custom parts will be required for this build, but I have to be smart and not build something I can get off the shelf or by outsourcing smartly.

4. Stealth! I was hesitant to ride my folding bike for awhile after the Boston Marathon Bombing, and for good reason. It looks like a bike-bomb. And with the (stupid ass) anti e-bike sentiment in NYC... Well, I need to make my bikes look less... threatening.

5. Grocery getter. This is actually part of the primary objective. I am not shy about bringing my folding bike into the grocery store and using it as a carriage. It makes the bike 100% theft resistant, it saves time locking/unlocking and it ensures I never buy more than I can carry. The A-Line on the other hand - it has the turning radius of an aircraft carrier and would draw so many curious people that I am just not going to ever bring it into a store. Concurrently, it is too expensive and valuable to leave outside, even with a tough lock and GPS tracker. Combined, that means the A-Line is not a bike I can ride if I plan to stop for groceries on the way to/from work. My next bike will be "grocery store friendly".

6. It will be "stairway friendly". I must have low enough weight and small enough dimensions that I can carry it up a flight of stairs. I can carry the A-Line up & down the 4 steps to go into and out of the basement side door - but I fear it's too heavy and big to carry up a full flight of stairs. Conversely, I've carried the Dahon up and down multiple flights of stairs - mostly in subway stations (so "wide" stairs are an implied parameter of this goal). The size and weight of this bike will likely be between the two bikes - but centering the weight might make it comparable to the Dahon in this regard.

More to follow. If I make changes or additions to these major goals, I will log edit them inline but note them below:
-----------------------------------------------------
Changes:
15 September 2013: Added the number 6 Major Goal: the bike must be stairway friendly.
Last edited by MattyCiii on Sep 15, 2013 1:02 pm, edited 3 times in total.

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Re: MattyCiii's third build

Post by MattyCiii » May 07, 2013 7:52 pm

Minor Goals: The "nice to have's".

1. 40 mph capable. In metro Boston city riding, 32-33 mph has been plenty. I'd like to make a bike that can handle 40, then dial the top down in gearing and/or software to say 35mph. And with CAv3, use the multiple profiles for a "commuter" mode and a "catch that m#f#r" mode.

2. 12 mile range. An "honest 12 mile range", meaning at aggressive throttle, little human input, and with some room to spare. This is doable with 50v and 10 Amp Hours I think. The A-Line, the rotational inertia bloated beast that she is, consumes about 35 watt hours per mile with my everyday aggressive riding. The next bike should have a lower power consumption than the A-Line, but will likely be above the 20 watt hours per mile of the Dahon.

3. All weather capable. I ride year round and love it. But rain and mud are a downer, so mud guards are a must. They were trivial on the folding bike yet still defy me on the A-Line. Bike number 3 will have mud guards. And everything else that makes a four season bike:
* Weather resistant enclosure for the controller.
* Illumination lights (bright white road facing lights in front) so I can see where I'm going in the dark and rain.
* Indication lights and reflectors so I'm more visible to others in the dark and in foul weather.

4. Kickstand Friendly. This is the natural offshoot of the "grocery getter" Major Goal. Without a kickstand, I often have to wait, holding the bike up, while some granny compares the unit price of coke Vs pepsi. "Can I lean the bike up against this shelf of egg cartons?" I wonder. "Better not risk it". A nice center-mounted double kickstand will make food shopping easier, and troubleshooting the rear wheel (brakes, chain drive, truing) a snap for those times when one needs to stop anywhere and troubleshoot problems.

More to follow. If I make changes or additions to these minor goals, I will edit them inline but note them below:
-----------------------------------------------------
21 May 2013: Threw in a couple of clarifications under #3, "All Weather Capable"
Last edited by MattyCiii on Sep 15, 2013 1:06 pm, edited 3 times in total.

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Re: MattyCiii's third build

Post by MattyCiii » May 07, 2013 8:03 pm

Design Choices: What I'm thinking of doing to build a bike to meet my primary objective and major/minor goals.

1. 16" Scooter Tires. DOT Rated, thick and cheap. But not so large as to be a massive flywheel. I've specced a 16" x 2.25" tire that looks like a decent road slick for under $20. It'll work on a bicycle 406mm rim (no more "bike hub, motorcycle rim" problems), and it's not too wide to fit on a bus rack. Also note:
* The 2.25" is probably the widest my chain line will allow (based on current constraints of the Project Velobration: The Common Power Module). That's not likely going to be a problem, because I can still use BMX/406mm rims and tires.
* I'll probably keep a spare rear wheel built up, with everything on it including spare tube and tire. Put the ice/spiked tire on it in the winter, maybe a BMX knobby on it in the summer.
* Out front... it's possible to change a tire and tube on a Lefty without even removing the wheel from the bike. I'll probably not keep a spare front wheel laying around until/unless I actually need one.

2. Cannondale Lefty Fork. I love the lefty on my A-Line, and the 2013 model is supposed to be better. But in any event, the fact that it's a mono-pole fork means the folding bike attribute of this bike will fold more compactly (note to self: Hinge pivot must be on the right for this to be an advantage!!!)

3. RC Drive. Go with what you know. I've used CAv3 + Castle Creations HV-160 + Astro Motors 32XX for my other builds. I have experience, and I have spares. These things have been rock-solid reliable, so I'm sticking with a winning combination.

As I look at my handwritten notes from the weekend, there's more... but some of my design choices are better described in the "Project Velobration: The Common Power Module" thread.

More to follow. If I make changes or additions to these design choices goals, I will edit them inline but note them below:
-----------------------------------------------------
21 May 2013: Changes to #1 - added info about using either bicycle or moto tires.
Last edited by MattyCiii on Sep 15, 2013 1:08 pm, edited 5 times in total.

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Re: MattyCiii's third build

Post by MattyCiii » May 08, 2013 9:47 pm

I've purchased the tires, tubes and rims. For the front, I'm going to use a Cannondale Lefty. I bought a new hub, and had spokes laying around from my A-Line build - see how it originally was going to use 16" moped tires on 406mm rims?. So I built up the front wheel. To make it completely bomb proof, I put 2 ounces of Stan's Tubeless fluid in the tube. Should I run over a spike and get a hole, Stan's will seal it instantly.

Here are the glamor shots:

This is nothing special. A 16" x 2.25" scooter tire. DOT rated to 75mph, and less than $20. It'll probably last 10,000 miles.
Image

Road slick tread pattern:
Image

It's not much, but it's a start. This is the "big build", the one where I take what I've learned from thousands of miles riding, and two very different, very competent bikes - and make something insanely great.
Last edited by MattyCiii on Sep 15, 2013 12:51 pm, edited 1 time in total.

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Re: MattyCiii's third build

Post by MattyCiii » May 09, 2013 8:37 pm

This post is a re-package of some comments I originally had embedded in my first post. I want to keep the first four posts "all about the plan", so I teased the junk out of that post, and I am repackaging/re-posting it here, with a little more info. Here was the original, under "User Requirements". The removed portion marked in italics and bold:
MattyCiii wrote:4. I will keep weight and complexity away from the wheels. About 3 weeks ago I dodged a douche bag driver on the folding bike, and hit a horrific pothole. I nearly lost control of the bike, and was surprised I didn't get a snake bite flat. Braking soon after the event, I felt a slight "pulse" in the brakes, that has since gotten progressively worse. Last night I looked - the rim sidewall is cracked and it is not safe to ride. My "simple wheels" User Requirement is to keep expensive/heavy/complex things away from the wheels and move them somewhere else. This in turn should mean less expensive wheels - easier to justify having a spare pair on the shelf (for dings, crashes, etc, or for show tires, knobbies, etc.) It will also mean lower weight, less unsprung mass, and better suspension response.
While I've obviously gone to great pains to identify exactly what I want in this build, one could sum up my primary objective as "a bike that has the best qualities of my first two bikes, but with one major enhancement: the Common Power Module thingy".

This particular User Requirement is borne of my experience with the Dahon folding bike, as illustrated by the cracked sidewall on the front wheel: Replacement parts are just impossible to find.
1. The front fork, and therefore front hub, is extra narrow to be a little smaller when folded. It's 74mm or 80mm wide (I can't recall, and for this story it's all the same). So it's near impossible to swap out the front hub except with a (hard to find) Dahon. The front hub is drilled for 20 spokes.
2. There are plenty of strong, great quality 406mm rims out there. There just aren't any drilled for 20 holes.

I've figured out how to lace the 20 hole hub into a 36 hole rim - but it is not pretty. And I'm too tired to try to tension and true it now - so heaven knows if it will even work.

And, as if it's necessary, I got further validation of my choice of the moped tires on the way home tonight. In spite of the 3 ounces of Stan's Tubeless fluid in my rear bike tire tube, I got a flat on the way home. The Stan's just made things messy. In contrast, the 16" moped tires I'm using on the next bike are very thick, yet just as easy to remove from the rim to patch as a bike tire.

As far as weight is concerned: The front wheel of my A-Line weighs a whopping 15lbs, while the front wheel of the next bike weigs 6.4lb.
---------------------------------------
Updated: 22 May 2013: To add to the weight comparison I list immediately above. I also weighed a standard Dahon 20" front wheel (with tube & tire mounted), and it came in at 2.4 lbs. Therefore the front wheels I'm using for this build are 2.5 times the mass of bike wheels, while the 21" diameter A-Line wheels are 6.5 times as massive.
Last edited by MattyCiii on Sep 15, 2013 12:52 pm, edited 2 times in total.

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Re: MattyCiii's third build

Post by MattyCiii » May 21, 2013 11:11 am

Minor update. Parts shipped to build the rear wheel.
I've had the rim forever (from Recumpence's 20" x 47mm group buy). But for so long I've been building rear wheels around NuVinci's, I was actually a little overwhelmed with the options for a standard rear hub. I ended up buying a Shimano FH-M756L XT Rear Disc Hub (36H Rear 6-bolt Disc) from Amazon. It arrived over the weekend, so I could measure it's dimensions and order the spokes. For the record they are:

Recumpence 47mm rims, ERD = 384mm
BCD of hub flanges: 60.5mm
Left flange center from center of hub: 32.5mm
Right flange center from center of hub: 21.5mm

Spokes: (calculator: http://www.bikeschool.com/tools/spoke-length-calculator)
3-cross pattern.
Left spokes: 180.5mm
Right spokes: 179mm

So I ordered some 13/14 Ga butted Sapim spokes in black from Holmes Hobbies. With luck they'll arrive before the weekend and I can spend some zen time building up the rear wheel.
Last edited by MattyCiii on Sep 15, 2013 12:53 pm, edited 1 time in total.

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Re: MattyCiii's third build

Post by richmpdx » May 21, 2013 1:46 pm

Do you have an off-the-shelf mud guard in mind that will work with 16" moped tire? I saw some of your efforts to make a custom PVC fender in the A-line thread. I am interested in mud guards as I use my bike year around in Portland, OR and mud guards are essential. I believe that the 16" moped tire is significantly larger than say a 20x2.0 Schwalbe Big Apple bike tire, so it seems questionable if bike 20" full fenders such as the SKS or Planet Bike fenders would work. Are you perhaps thinking of one of the more abbreviated mud guards? Or something else?

Rich

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Re: MattyCiii's third build

Post by MattyCiii » May 21, 2013 3:10 pm

I don't have a plan yet for mud guards. I'm hoping I can find something worthy off the shelf for the rear. I'll be looking for something with 180 degrees of arc, plus or minus. I just measured my completed wheel, and it has a 65" circumference (with the 2.25" moto tire). That's a 20.7" diameter. So I hope a Planet Bike or SKS will do the trick. The fenders don't really need to be wider than the tires - since the water should mostly be slung from the center of the wheel.

If I stick with the design choice of using a Cannondale Lefty, the front mud guard will be a problem - simply because I lack an attachment point on the right side. I have a plan to fix that, but it's a long way off.
Last edited by MattyCiii on Sep 15, 2013 12:54 pm, edited 1 time in total.

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Re: MattyCiii's third build

Post by richmpdx » May 23, 2013 3:09 pm

Thanks for the info. Is the 16" tire something different than a Pirelli ML75? I thought that the ML75 came in 16x2.5 and 16x2.75 and several ES posts have mentioned a diameter of about 21.5".

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Re: MattyCiii's third build

Post by MattyCiii » May 23, 2013 4:23 pm

What I'm using is Shinko 16x2.25 R714.

I used to have a pair of 2.5" Pirelli ML-75's, pictured below. In the picture, they're mounted to the same "20 inch" (406mm) BMX rims I'm using now. So, I'm presently using a different brand of tire, but both the Shinko and the Pirelli are 16" moto (moped, scooter, etc.) tires and therefore fit the 406mm "20 inch" BMX rims like they were made for each other.
Image
Last edited by MattyCiii on Sep 15, 2013 12:55 pm, edited 1 time in total.

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Re: MattyCiii's third build

Post by MattyCiii » May 25, 2013 5:23 pm

Quick update:
Spokes for rear wheel arrived, so I dropped what I was doing and laced up the rear wheel. My first "Three Cross" wheel. I'll tension and true it tomorrow or Monday.

This is my first rear wheel in a very long time that did not have a NuVinci. It's so light!!!
Last edited by MattyCiii on Sep 15, 2013 12:55 pm, edited 1 time in total.

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Re: MattyCiii's third build

Post by MattyCiii » May 26, 2013 4:17 pm

Rear wheel tensioned & true'd, protected with rim tape, and adorned with tube and tire. I now have a complete wheel set for the bike. Weight so far: ~13lbs.

One of these days I'll have to weigh my Dahon folding bike, to get a baseline (Edit: The Dahon is 75 lbs). This bike will definitely be heavier, but hopefully not by much. Say maybe 12-15 lbs.
Last edited by MattyCiii on Sep 15, 2013 12:54 pm, edited 3 times in total.

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Re: MattyCiii's third build

Post by MattyCiii » May 27, 2013 6:41 pm

Quick update:
To illustrate my "keep complexity away from the wheels" requirement for this build: Here's a picture of the rear wheel of my RC drive Norco A-Line. Not only is there about 25lbs of weight/rotational inertia there on the wheel, but probably another 10lbs of brake caliper, motor mount and RC drive unsprung back there as well. Two chains - one with a tensioner only millimeters from the spokes. All this gets mud and slush slung up at it. No thanks... I'd like to get those drive components a little more central and possibly even protected!
Image
Last edited by MattyCiii on Sep 15, 2013 12:53 pm, edited 1 time in total.

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Re: MattyCiii's third build

Post by MattyCiii » May 27, 2013 7:27 pm

I just stumbled across an early concept drawing for this build I did some months back. Looks kinda ridiculous doesn't it?
Image

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Re: MattyCiii's third build

Post by MattyCiii » Sep 24, 2013 10:47 am

Not a lot of activity here. But this bike is still being built!

I ordered & received a 2013 Cannondale Lefty from Project321, and it arrived today. It's a fine piece of machinery!
Image

Since I already have a wheel built up for it, it's ready to roll. Add some cranks and a seat and I'm riding in style on my very own unicycle!
Image

This will be an all weather bike. Having the front wheel and fork now allows me to start a sub-project: Find, or make, and appropriate front fender and mounts. I think I can handle the mounts just fine with parts on hand. The fender... well, I'm thinking of custom fabbing one in fiberglass. I have a full 14mm between the lefty leg and the tire - so I have plenty of space for a fender to clear.
Image

Disc rotor not installed yet. I have a few on hand, but the rotor can be installed later. I'll have to decide whether I want to use brakes I have on hand (I have a pair of Magura Gustavs with pressure activated e-brake cutoffs), or try cable actuated discs.
Image

Another pic of the lower fork
Image

This bike is going to be a folding bike. So, I need a folding handlebar stem. An off-the-shelf Dahon folding stem interfaces just fine with the Lefty's steerer tube"
Image

The cap bolt is hidden inside the folding mechanism, so people won't know how much I spent on the headset.
Image

Here's another shot of how the parts will interface. Of course I need to have an actual head tube/frame before I can make any more forward progress with this build.
Image
1st build: Dahon Jetstream folding bike. Quick, reliable, capable of 32mph. Light enough to lift, folds for easy transport by car/bus/train.
2nd build: RC powered 2009 Norco A-Line. Top speed 39mph. Built like a tank, it's resistant to Boston potholes, can stop on a dime, easily goes up/down curbs when necessary.
3rd build (just started): Scratch build ultimate utility bike. Based on a common power module using a NuVinci left side freewheel.

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Re: MattyCiii's third build

Post by MattyCiii » Sep 28, 2013 1:37 pm

Quick updates:

1. Work has been busy lately, but it's important to keep up some forward progress. So I've started making a custom front fender for this bike. I have not looked very hard, but I doubt I'll find a front fender that fits the new bike well enough for my high standards. So, I'm going to make one - out of fiberglass.

No pix on hand (sorry), but what I have so far is the wheel, covered in food "cling wrap", is mounted to the Lefty and clamped into the bike stand. On about 270 degrees of the tire, I've stuck 5/8" foam weatherstripping onto the tire in parallel strips, basically making a foundation for a mold that's parallel to the wheel's surface, but 5/8" away. Over that I've placed some fiberglass tape used for sheetrock joints, and finally some plaster of paris to make a hard coating on this foundation. I suppose if I build up the plaster by 3/8", I'll have a fender that's a perfect fit spaced 1" above the tire.

Pictures and more info to follow as I complete this "mold" and get ready to do my first ever composite work.

2. This project is barely started... it'll be a long time before I have a complete bike. So I'm thinking - once this fender is complete and mounted, maybe I'll swap this wheel & fork onto my Dahon folding bike and place that bike's front end on the shelf awhile. That bike is getting pretty beat up - especially the front suspension - and I'm getting concerned something bad will happen long before I complete this bike, its intended replacement.
1st build: Dahon Jetstream folding bike. Quick, reliable, capable of 32mph. Light enough to lift, folds for easy transport by car/bus/train.
2nd build: RC powered 2009 Norco A-Line. Top speed 39mph. Built like a tank, it's resistant to Boston potholes, can stop on a dime, easily goes up/down curbs when necessary.
3rd build (just started): Scratch build ultimate utility bike. Based on a common power module using a NuVinci left side freewheel.

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Re: MattyCiii's third build

Post by MattyCiii » Oct 01, 2013 2:44 pm

As mentioned in my last post. Here are some pictures of my effort to make my own fenders for this bike:

I put down a base of insulating foam strips, then covered them by hand with plaster. My original hope was that the foam insulation would absorb the wet plaster and harden up, but it seems the foam is still quite pliable. That's a shame, as it makes the mold weak.
Image

Here's a closer look. The profile of the fender will be a semicircle curve, with a bit of a ridge in the middle. I hope to put an LED strip on the underside of the ridge and seal it, to have a nice lighted fender (fiberglass is translucent and should hopefully interact nicely with the LEDs)
Image

To get the fender even and smooth, I created a template of the cross section on the MakerBot. This, clamped rigid to the fork, will skim off excess plaster as I layer on the next few coats providing a nice perfectly shaped curve to the profile. I hope!
Image

After taking those pix I did a little plaster work and the plan is working out quite well. As I layer on more plaster, it builds till it is touching the profile, and as I turn the wheel excess plaster is scraped off. I have at least 2 more mixes of plaster to do to get the mold near finished - probably more like four. I hope to take pix as I go, but it's messy work.
1st build: Dahon Jetstream folding bike. Quick, reliable, capable of 32mph. Light enough to lift, folds for easy transport by car/bus/train.
2nd build: RC powered 2009 Norco A-Line. Top speed 39mph. Built like a tank, it's resistant to Boston potholes, can stop on a dime, easily goes up/down curbs when necessary.
3rd build (just started): Scratch build ultimate utility bike. Based on a common power module using a NuVinci left side freewheel.

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Re: MattyCiii's third build

Post by recumpence » Oct 01, 2013 7:26 pm

How did I miss this build?

Looks good!

Matt
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Re: MattyCiii's third build

Post by MattyCiii » Oct 02, 2013 9:04 pm

recumpence wrote:...Looks good!

Matt
THANKS Matt!

Both my Recumpense reduction equipped bikes are still running good as new. But alas, with me there will always be a "next build".

This whole build will take awhile to complete. The current phase - fenders - is taking awhile as I want the plaster mold for the fiberglass to be perfect. I've never worked with either plaster or fiberglass before, so...
1st build: Dahon Jetstream folding bike. Quick, reliable, capable of 32mph. Light enough to lift, folds for easy transport by car/bus/train.
2nd build: RC powered 2009 Norco A-Line. Top speed 39mph. Built like a tank, it's resistant to Boston potholes, can stop on a dime, easily goes up/down curbs when necessary.
3rd build (just started): Scratch build ultimate utility bike. Based on a common power module using a NuVinci left side freewheel.

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MattyCiii
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Location: Boston, MA, USA

Re: MattyCiii's third build

Post by MattyCiii » Nov 27, 2013 1:50 pm

Quick update on the fiberglass fender project:

I gave up on using plaster after awhile, and went with Bondo. The mold plug started to take a nice shape:
Image

Here's the plug as it intersects the sculpting tool. I would mix up and lay up a thin layer of bond, then rotate the wheel through the sculpting tool to skim off excess.
Image

Kinda looks like a fender!
Image

Fast forward several weeks. I've been putting in an hour here and an hour there till I felt the plug was as good as I can get by "building up". Once I got to that point, time to sand it down. After coating the plug with 8-10 layers of sand able primer (touching up with Bondo spot putty every once in a while), I started wet and dry sanding. I've never done anything like this before, so I'm trying every technique I can read about to get this thing side and smooth.

I'm now close to done with the plug. I've been refining my techniques sanding up one side - and I'll repeat the process with perfected technique on the other. Here's the finished side. Hard to see with my blurry cam, but to the eyes, I can see the details of the florescent light fixture in the reflection!
Image

Here's another shot:
Image

This was done by wet sanding then dry sanding with grits: 400, 600, 1200, 2000, then 3000. When dry sanding, I polish the dust off the plug after every sanding with an old cotton T shirt.

Next steps:
1. Layup 4-5 coats of mold release wax
2. Hot glue some flanges along the end of the plug so the mold does not wrap around.
3. Make the mold - Gelcoat, let mostly set, epoxy & glass, let mostly set, repeat once or twice more.
4. Release plug from mold
5. Build a structure to support the mold.

Once all that's done I can start making fenders!
1st build: Dahon Jetstream folding bike. Quick, reliable, capable of 32mph. Light enough to lift, folds for easy transport by car/bus/train.
2nd build: RC powered 2009 Norco A-Line. Top speed 39mph. Built like a tank, it's resistant to Boston potholes, can stop on a dime, easily goes up/down curbs when necessary.
3rd build (just started): Scratch build ultimate utility bike. Based on a common power module using a NuVinci left side freewheel.

Murfix
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Location: Belgium

Re: MattyCiii's third build

Post by Murfix » Nov 28, 2013 7:59 am

My first post outside of the skateboard section:

Very nice dude! You've given me a few ideas to make my own very first fiberglass mold!

I'm reading up on the bike forum and I'll definitely be learning a lot from your experiences with this build.
Keep it up! :D
Memo to myself: Screw it, just do it!
1 Apr 2013 - Start pre-engineering my first EV build!
6 Aug 2013 - Ordered all parts for my Emtb 8s 2x2kW 270kv Alien ESC setup.
3 Sept 2013 - All parts have arrived: on to the build!
23 Sept 2013 - First test ride: AWESOME!
7 Feb 2014 - Upgrade finished: 3kW motors, 12S Alien ESC, entire new drivetrain and LED's!
Build topic: https://endless-sphere.com/forums/viewto ... 35&t=52390

900steve
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Re: MattyCiii's third build

Post by 900steve » Nov 28, 2013 8:20 am

That plug is looking sick!
I won't be around much the next few weeks, lots of traveling to do. Maybe the 28th and 29th, let me know if you'll be around then.
-steve

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MattyCiii
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Re: MattyCiii's third build

Post by MattyCiii » Nov 29, 2013 5:59 pm

900steve wrote:That plug is looking sick!
I won't be around much the next few weeks, lots of traveling to do. Maybe the 28th and 29th, let me know if you'll be around then.
-steve
Excellent, I'll try to keep that weekend open (50/50 chance as you know). In the mean time I hope turning the plug into a mold is a one man job, because I really want to reclaim this wheel and fork!
1st build: Dahon Jetstream folding bike. Quick, reliable, capable of 32mph. Light enough to lift, folds for easy transport by car/bus/train.
2nd build: RC powered 2009 Norco A-Line. Top speed 39mph. Built like a tank, it's resistant to Boston potholes, can stop on a dime, easily goes up/down curbs when necessary.
3rd build (just started): Scratch build ultimate utility bike. Based on a common power module using a NuVinci left side freewheel.

User avatar
MattyCiii
100 kW
100 kW
Posts: 1483
Joined: May 05, 2007 2:06 pm
Location: Boston, MA, USA

Re: MattyCiii's third build

Post by MattyCiii » Dec 04, 2013 7:21 pm

Took the day off to do some repairs on my truck. Had some extra time, so I decided to move the fender project forward.

1. I've been putting layers of mold release wax on the plug for the last several evenings - I probably have 6 full coats of wax on the plug.
2. Using cardboard, foil tape, modeling clay and hot glue, added flanges to the plug.
Image
3. Sprayed the plug with PVA using a "Preval" sprayer. I had problems with it at first and thought I would have to quit for the day. But with some advice from google, figured out how to use the sprayer and got a good layer of PVA on the plug. When dry the PVA made the plug look like glass.
4. I mixed up a gel coat - what will be the working surface of the mold. I basically used the finish epoxy, but mixed in a few spoonfuls of glass bead powder to thicken it to a molasses-like consistency. I then applied the thickened epoxy to the plug. The plug is round of course - in 2 dimensions - so the epoxy flowed down the sides and started dripping onto the drop cloth on the floor. I'm writing this as I wait for the gel coat to cure enough for the first reinforcement layer. When you can touch the gel layer with a nitrile gloved finger, feel tacky but have none of the epoxy stick to the glove - it's time for the next layer.

Wish me luck!
1st build: Dahon Jetstream folding bike. Quick, reliable, capable of 32mph. Light enough to lift, folds for easy transport by car/bus/train.
2nd build: RC powered 2009 Norco A-Line. Top speed 39mph. Built like a tank, it's resistant to Boston potholes, can stop on a dime, easily goes up/down curbs when necessary.
3rd build (just started): Scratch build ultimate utility bike. Based on a common power module using a NuVinci left side freewheel.

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