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Matthew Martin
Starting Member

USA
18 Posts

Posted - 10/17/2017 :  16:17:22  Show Profile  Reply with Quote
I am still here, Just sitting back and taking great advice in and thinking on my project a bit.

In response to the idea of a coro fairing, I do like the idea and simplicity. However coro fairings general have a homemade look to them, though they can look very nice to a person that knows what it is, you have to understand that I am in high school which is a judgmental place. It is already a "radical" idea to ride a bike like the one modeled as well as a regular upright as a means of transport. It is not very common and I will admit, weird, however I want to make my bike look as professional as possible in order to create the facade that my bike is one of many (group), which reduces the weird factor by just a little bit and may create interest that may have not been there if the bike looked homemade. A "homemade" look may inadvertently create a situation where people may not want to ask their questions because they may not want to associate with me or the bike, a nicer looking bike makes me more approchable. I know I am already going to be singled out but a "professional" looking bike may create greater awareness for human transport as well as encourage others to be tolerant of bikes in general. I already know I am different from an interest perspective, but I want to be able to associate with people and tell them what it is that I am doing. If my "homemade" looking bike is there first impression, it may turn away many people because it is weird and nobody wants to talk to the "weird" kid, and because they don't ask me, they assume and make uneducated conclusions about the bike and myself.All of this is because high school is just a place where kids are not open to new ideas that are different, because everybody wants to fit in. So if I can show that I am a part of a community, it is more inviting (subconscious)than if I was the only one with a faired bike. Most people are followers, not leaders. If a person were to see a professional looking bike, it creates a more profound impression and may prompt that other person to look into these types of bikes, where as if It looked homemade they may loose interest.

But that's a lot of reasoning to just not use coroplast, but I also want to learn howto work with fiberglass as I will probably be using it in future projects, but the reasons listed above are the most relevant.

So yes I will definitely plan on using coroplast to plan and test how much space there actually is, but I probably wont make an entire coro fairing but just mock up pieces.

And yes I am just like any other high-schooler in the fact that I do care what others think, but just not as much as others may. If I were older and did not care what others think, I would probably use coroplast. But I am not older, and to a certain extent I do care what others think. And who knows, a great first impression of what human power vehicles can look like, may inspire others to get into human powered vehicles.

Sorry for no reply and I hope my response makes sense. The human power group is small, and if there is ever a chance that this faired bike and recumbent group becomes more mainstreamed, it has to become more appealing and perhaps more relatable to younger people, as young people are more likely to change a culture as a whole. And because young people (like myself) are concerned with looks, creating nicer looking projects may play a large role in in creating an appealing alternative to a car. However the human powered vehicle scene probably will not become popular with the large masses as people are lazy.

Edited by - Matthew Martin on 10/17/2017 17:43:56
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Speedbiker
human power expert

USA
3744 Posts

Posted - 10/17/2017 :  20:52:52  Show Profile  Reply with Quote
Just imagine the future of a young man who builds a composite liner in high school. What will follow in the years to come? Cars. Airplanes. Flying cars?? This is how it starts.
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Jerry
recumbent guru

USA
967 Posts

Posted - 10/17/2017 :  22:13:31  Show Profile  Reply with Quote
Funny you think that young people will think less of a coroplast built bike. I get just the opposite every where I go. High school, middle school, colleges, and the old people all think mine is very cool. Then when I blast past at 30+ mph, they really go crazy. But I also understand you want a hard shell liner. Go for it. Don't let anything or anyone stand in your way. Determination is 90% of the battle. Who knows, your design might be the next world record holder. I am looking forward to the build.
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nickyfitz
Starting Member

France
37 Posts

Posted - 10/18/2017 :  04:04:19  Show Profile  Visit nickyfitz's Homepage  Reply with Quote
Hi Matthew. Now that you have successfully reclaimed your thread :-) perhaps another old fossil could offer his two cents worth. Firstly, I add my encouragement to your great project and I think you should stay true to YOUR vision of what you want. However, you should recognise that what you are hoping to achieve is possibly the most complex of challenges to a HPV builder. Not only is it to be as sleek and aerodynamic as a Battle Mountain streamliner, but it also has to cope with all the practicalities of riding it in an urban environment; turning tight corners, starting and stopping, getting in and out unaided, light enough for hills and urban acceleration, a huge gear range to cope with up and down hills, all round vision and visibility to other road users, no overheating, etc etc.

You are clearly very smart and mature in seeking advice from old codgers with more experience than you. And you have already been given some very pertinent advice from some of the best HPV experts in the world. Their insights come from many years of trial and error, getting it wrong, and learning from their mistakes. And here I think lies the key piece of advice I would like to suggest to you in pursuing your project. Don't expect the journey from CAD concept to riding a successful street-liner to be short and simple. No matter how well thought-out your ideas are, how well designed, and how well implemented, you will most certainly come stuck with unforeseen issues, elements that don't work as intended, and difficulties with building it that delay and demotivate.

But there are ways to deal with these setbacks. Divide and conquer! You should make extensive use of prototyping to check how your ideas work in practice.

I'd suggest you build a simple recumbent first to check that the drivetrain functions reliably, that its dimensions fit your body, that its geometry is stable, and - most importantly - that you can ride it comfortably. As Thom has commented, riding a laid back low rider recumbent can be challenging for a novice, and when it is then enclosed entirely in a closed shell it becomes a total nightmare! I agree with Thom that you should first become experienced and very comfortable at riding an unfaired recumbent whose geometry resembles that of your proposed street-liner before you leap into building the final product. This will also give you valuable insights into how you should design the steering mechanism (since a LWB with a laid back rider will require a remote linkage system), what body position works best, and where are your feet/knees/elbows/shoulders likely to rub on the enclosed shell and/or bash into bits of the bike as you pedal or steer.

I also agree with Jerry that building with coroplast offers the significant benefit that you can easily prototype, test, and modify the bodyshell when (not if!) you find it doesn't quite fit as intended, or needs to adapt to some unforeseen problem. As others have commented, I found that iteratively making the seat back more and more upright than I was used to was massively better for balancing and riding an enclosed streetliner. Steve (Speedy) Delaire has warned that you need to pay careful attention to the relative positions of the CofGravity and CofPressure and you may only be able to get this right by riding and testing a prototype on the road, and then reshaping and modifying the bodyshell (repeatedly!) as needed. You can't easily do that if it's built in carbon fibre. That's not to say that your final bike needs to be made from coroplast, as we can all understand why you are aiming high for a sleek professional look. But all engineers build and test with prototypes, and architects build balsa wood models before constructing in steel and concrete!

Finally, I have no personal experience of building with carbon fibre but I know that it is a skilful, messy, and HUGELY time-consuming process. I did once make a fibre glass recumbent seat and I decided I never wanted to touch any fibres or resin again! But John Tetz has demonstrated that you can build a sleek, curvaceous, and professional-looking bodyshell from closed cell foam that offers almost the same performance and look as a CF fuselage. It's a material that has many advantages over CF for the HPV builder, and worth checking out seriously before you decide that only CF is good enough for your goals.

I would love to see you progress your project Matthew as I too have been dabbling with a street-able 2 wheel streamliner project for a while. I chose to use a welded steel space frame structure with closed cell foam panels to shape the bodyshell and stretched lycra over the top for a smooth finish. I hope you'd agree it doesn't look too shabby, but maybe the colour wouldn't be appropriate for the street cred you need! :-)

Keep us in touch with your progress. You can see that we are all gunning for you and there are plenty of good people here who can help you achieve your goal. Good luck!



Nick

Previous bikes:
https://www.flickr.com/photos/139728134@N08/albums/72157673027547665
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Jerry
recumbent guru

USA
967 Posts

Posted - 10/18/2017 :  08:09:59  Show Profile  Reply with Quote
Thanks Nick, you just said what I was trying to say, but you did it a lot better! Coroplast and spandex are a lot cheaper to test and ride before trying to build the perfect street streamliner. I remember rebuilding my first attempt several times just to get it to fit all my body parts, then get it to turn without the wheels rubbing on something. After being blown over by a sudden 45 mph side wind and cracking my hip, I decided not to build a hard body streamliner, but to keep it simple with coro and spandex. I am like you and Joel Dickman, with spandex, you can remove it when the wind picks up.

I hope Matthew all the best.
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Speedbiker
human power expert

USA
3744 Posts

Posted - 10/18/2017 :  09:08:08  Show Profile  Reply with Quote
Jerry, imagine the excitement you'd generate if you had a fancy, 35 pound, carbon Daniel Fenn velo and hit 40 mph in 100 feet. If I had your $$$ I'd have two!
Good looking street liner Nick. I think we've beat on Matthew enough about prototyping. He is a very sharp fella who has done his research. Thanks
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Matthew Martin
Starting Member

USA
18 Posts

Posted - 10/18/2017 :  15:11:37  Show Profile  Reply with Quote
I completely agree with what you have to say Mr. Nick, I was planing to do most everything you listed. I have built many other things( many which have not worked) and I understand that many things don't go as planned during a project. I have built a recumbent already and It was a success, but I learned a lot, as it was my own design and did not know if it would work or be comfortable. I made many changes to the design that I would have never thought to have made on paper. So I can't deal with issues that I don't know exist, so I will have to deal with them along the way. This is only my second project that is using CAD software, and I am using it mostly to make sure the fairing will have enough room. The renders may make the fairing look slim and sleek but the fairing that I modeled is actually pretty wide for a streamliner (22 in) at the shoulders and hips. So its not exactly battle mountain fast.

I should have probably restated my potential use of coroplast, and just said that I probably will use it as a prototyping material. I definitely will make sure that my shape works before I invest much more money into making it a hard body, whether using coroplast or another method to test this. Also I am planning on making the bike before the fairing and will test the frame geometry first before proceeding to make the fairing.

I have seen your page on this forum when doing research and enjoyed your build (its not shabby).

Carbon fiber is out of the question for me (way to pricey) but I want to get experience with composites on a relatively simple (compared to what I want to do in the future) shape. I will make sure the shape that I go with will work for me, before I start any fiber glassing.

I may not be successful with this project, but I need to try for myself, because it may work

On a different note, Mr. Jerry, you mentioned that a side wind caused you to crack your hip (I am sorry that happened) but If you could help me understand that situation a little better I may be able to design my bike better. For example if it was a direct crosswind or at an angle, what the bike looked like... Etc.

Thank you

I also found this video on mold making with joggles to be very helpful
https://www.youtube.com/watch?v=H5A7_oPAw9c


Edited by - Matthew Martin on 10/18/2017 15:13:59
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Jerry
recumbent guru

USA
967 Posts

Posted - 10/18/2017 :  15:39:45  Show Profile  Reply with Quote
Sounds like you have it going on there and understand the principles Matthew. Good for you.

I was riding a swb Lightning Phantom with a Lexan wind screen and a coroplast body. I had left off the top and bottom sections of coroplast because I knew it was going to be windy out. The wind was out of the west at 22-25 mph. I was headed south and leaning to my right to balance the coroliner against the wind, when the wind shifted without warning from the west to the east and at around 45 mph. It knocked me over before I could react. I am a fairly strong and agile person, but with shifting winds and a full fairing, you are going down. I would have been alright except my hip hit the crown edge of pavement, that is the rounded part of pavement. Maybe, and that is a big maybe, if the middle section had been spandex, it might not have knocked me over. I really don't think so though. It happened so fast, kind of like the way the wind acts in a tornado. I am not expert enough to say if you can design for this situation. Most liners stay home when the wind is blowing very hard.

Edited by - Jerry on 10/18/2017 15:41:41
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nickyfitz
Starting Member

France
37 Posts

Posted - 10/19/2017 :  05:05:45  Show Profile  Visit nickyfitz's Homepage  Reply with Quote
Matthew, you seem to have a very wise head for a young man at high school. And I like your favourite quote in your profile. You have already impressed us with your inspiration and the seriousness of your approach, now it's time to get down to the perspiration!

You clearly understand the scale of the challenge you have set yourself and you mention that a "successful" result may be hard to achieve. But think of it more in terms of the process than the product. However your project turns out you will learn immensely useful things along the way. And even if the result doesn't meet your own very high standards, nobody on this forum is going to denigrate your achievement. We know how hard it is to get it all right and, whatever your high school peers may say, you will have won our admiration for your efforts. Plenty of people here to applaud you and try to help you overcome any issues you encounter. I personally am sure you will impress us all.

Go for it! And send us lots of photos! :-)

FWIW, in response to your question to Jerry about cross wind effects, I too found my first test ride in windy conditions very scary! I removed the fairing at the nose and tried again. It was slightly less scary!

So I took advice from Warren and Speedy on the importance of getting the CofG as far forward as possible and the CofP as far back. It's not always easy! Also Tony Levand suggested I lower the nose so as to encourage airflow to go over it rather than around it. Again, not so easy. But I completely rebuilt the front of my frame with a smaller wheel, revised fork geometry and shorter cranks, and I put the rider in a more upright position with the handlebars in front of my knees so as to move my body mass forwards. If you compare the recent photo above to earlier pics in my previous bikes link below you can see how much I managed (to my great surprise) to improve the aerodynamics at the front end. The bike is now much lower and 18cm shorter at the nose, and only 6cm taller at the highest point (the rider's head). I can't tell you yet what difference that makes out on the road because with moving house and other commitments I haven't had the time to ride it out in windy conditions. But in any case, as Jerry said, unless you are intentionally testing aerodynamics you don't normally choose to ride a streetliner when it's windy!

Good luck!

Nick

Previous bikes:
https://www.flickr.com/photos/139728134@N08/albums/72157673027547665
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alevand
human power expert

USA
2908 Posts

Posted - 10/19/2017 :  06:33:47  Show Profile  Visit alevand's Homepage  Reply with Quote
Hi Nick, I like your bike, how is your SWB, FWD bike for touring? Do you ever loose traction up hills?



C:
Tony Levand
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nickyfitz
Starting Member

France
37 Posts

Posted - 10/19/2017 :  13:17:40  Show Profile  Visit nickyfitz's Homepage  Reply with Quote
For its maiden voyage this bike took me 1450km across the mountainous Massif Central of France and back. Weighing in at approx 15kg and with 12kg of luggage on the back (of which 3kg was tools, just in case....!) we didn't break any speed records but I never noticed any front wheel slip. And we went up some pretty damn steep hills I can assure you!

I've looked up the notes in my project file and I had measured the weight distribution with me on board (but no luggage) as 58/42% front/rear. So with 12kg or so of luggage behind me that would give approx 50/50 distribution.

It was my very first experience of bike touring, and the SWB FWD format was great. If ever I found myself in the wrong gear when starting off (eg on a hill) it's so easy to stand up, lift the front end, change gears and spin the front wheel to select a better gear. The big design error was to put the bottom bracket so high. I had intended to replicate the same body-hip angle as a DF bike thinking that this would aid my unadapted transition to "recumbent legs". In practice it caused early onset of lactic acid accumulation in my thighs and pains around my knees, and the seat angle was a tad too high so I also suffered some recumbent butt. Great trip though :-)

Nick

Previous bikes:
https://www.flickr.com/photos/139728134@N08/albums/72157673027547665
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Matthew Martin
Starting Member

USA
18 Posts

Posted - 10/28/2017 :  21:41:05  Show Profile  Reply with Quote
Been designing a fairing that could be made with coroplast. Uses 6 sheets but the cuts are pretty easy.



Used pepakura designer to design the cuts


Possible design for the bike fairing.

Are there any cheaper options besides coroplast for a mock up fairing?
Has anyone tried cardboard? I am not concerned with durability or weather proofing but just want to get a general idea of what this fairing feels like.

Suggestions welcome
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Speedbiker
human power expert

USA
3744 Posts

Posted - 10/29/2017 :  01:58:30  Show Profile  Reply with Quote
Coroplast was $20 a sheet last time I checked. It's a joy to work with, unlike cut up refrigerator boxes. Well worth it. And it will hold up thru all testing.
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Jerry
recumbent guru

USA
967 Posts

Posted - 10/29/2017 :  08:59:18  Show Profile  Reply with Quote
I just bought 5 sheets of coroplast at Home Depot for $19.57 each. They only carry white.
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alevand
human power expert

USA
2908 Posts

Posted - 10/29/2017 :  10:15:41  Show Profile  Visit alevand's Homepage  Reply with Quote
The nose is the hardest part to make from coroplast. It can be formed to a radius more than what shown in the cad, doesn't need the facets, but then again it easier to use facets and joint cad pieces like a kit. I use a heat gun. You can get 4x8 sheets from print supply for $20. You'll get a lot of internal reflections with a windscreen that horizontal. Its nice to be able to see the road in front of the bike for stuff like pot holes and rocks, so the nose shouldn't be higher than necessary.

C:
Tony Levand
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Speedy
recumbent guru

USA
882 Posts

Posted - 10/29/2017 :  16:42:02  Show Profile  Reply with Quote
Cardboard works out fine to create a test fit version.
Coroplast is lighter, stronger, better weather resistance.
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nickyfitz
Starting Member

France
37 Posts

Posted - 10/30/2017 :  18:28:10  Show Profile  Visit nickyfitz's Homepage  Reply with Quote
Don't laugh but I get a lot of good use from foam camping mats. Light, cheap, and readily available. Not as stiff as coroplast, but the plus side is the suppleness makes it easy to form - even into tight radii - and with some judicious cutting/shaping can be formed into 3D curves.

Nick

Previous bikes:
https://www.flickr.com/photos/139728134@N08/albums/72157673027547665
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alevand
human power expert

USA
2908 Posts

Posted - 10/31/2017 :  06:43:45  Show Profile  Visit alevand's Homepage  Reply with Quote
Ive used a camping pad to make a removable deck cover. That way I could roll it up for storage. Its PEX, same stuff as Zote foam, but thicker and smaller pieces. See John Tetz's pages on Zote foam: http://recumbents.com/mars/pages/proj/tetz/manual/0intro.html

Very light, offers some protection, but not skid resistant, has an insulation R-value of 2

C:
Tony Levand
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Jerry
recumbent guru

USA
967 Posts

Posted - 10/31/2017 :  08:07:16  Show Profile  Reply with Quote
See Richard Myers camping pad build here on this site.
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