News and Events

Keep up to date with the latest news and events of Modular Bikes.

Monday, August 28, 2017

A seat for the fast trike

Lines drawn on the plywood were to ensure the drilling was in the right place.

This jigging was used to hold the timber on the seat while the glue was drying, and

these 2 F-clamps screwed to a piece of wood to make the jigging more stable.

Glueing 3mm strips of ply together

Piece of frame material used to mount seat on workbench

Mock up of seat on trike
Hi

Over the last few days, I have been making a seat for my new fast trike and I'm almost finished.  I haven't really worked out the steering arrangement yet, but I want to get a low, aerodynamic seat in place before the steering is set up.

So this shows the seat setup, I am using plywood to mount a Performer seat I bought from Alex McNee which had been gathering dust in the shed.  It took me 2 goes to get the first 4 strips of ply glued together, but after that its been pretty smooth sailing.  In about 2 days, the seat will be done and I can move on to steerer, brakes, gear lever etc. etc.

Its been good having a speedo on my everyday trike.  I can only get anywhere near 40 kph on it by going down big hills, and there will be a lot of work to be done on this new trike if I'm to get up to decent  speeds.

Regards

Steve Nurse

Saturday, August 19, 2017

Printed Frame Separators

Current trike in Lorne during an Audax ride
Diagram of separators showing how they are kept in compression. 
Separators from Shapeways on my current trike.

Inside the frame are timber and tee-nuts.
The frame separators on the "40" bike were prototypes.  I hadn't worked out what was going on.
3d printed sample piece.  This had flat sections printed 1.6, 2, 2.4 and 2.8mm thick, and was designed to find out about the printer and how to avoid.....

this sort of thing: the printer makes hollow sections shown here with cross-hatch reinforcements.

Some replacement parts on the printer.

The 4 components making up the new spacers, shown with the finished part.  Inset: gluing the parts together.
Completed and on the frame.

 Hi, I have been using my home 3d printer to make some spacers which fit between the 2 halves of my recumbent trike frame.  This frame uses the same principle of gravity assistance used in my Velocino and separating Hercules bikes.  This mechanism has worked well in one of my frames, and the trike comes apart for when I take the trike on country trains and in the car.

Now I have a 3d printer and I wanted to try to make some frame separators at home.  With its current software, the printer won't print solid sections, and solids are needed for these parts as hollow parts would just crush.  So I worked out what maximum thicknesses I could print, then sliced up the spacer part into 4 pieces.  The H-shaped pieces were printed vertically and I didn't want to make them too tall, so I kept their height to 65mm, half the length of the previous parts from Shapeways over in the USA.  I think my home printed parts have fewer air-miles.

So the bits all fit together fine but the whole trike is not back on the road yet.  I aim to get this done by Thursday, and to ride into Uni on a finished trike on it.  Will report.

Regards

Steve (3d printed bike bits) Nurse





Wednesday, August 16, 2017

What Does 40 Feel Like?

Current Trike

Part from the Shed.  59 tooth is a big chainring.

Forks from the shed.  I picked out a few good ones from this lot and the rest went to recycling.

Frame for new trike.

Wireless speedo, I got 3 of these for about $10.00 each from ebay.
Speedo fitted


Hi

During Easter, I volunteered at an OzHpv record breaking weekend.  I helped out (a bit) on the Sunday of the event, which was held at the Ford Lara proving ground.  But on the Saturday of the event, Glenn Lacey broke the over 50's hour record for an unfaired trike as recorded here, on the World Recumbent Racing Association website.

So the record now stands at about 37 kilometres, and then I got to thinking, well, that doesn't sound that fast, and then I thought, well, I didn't really know, because I don't even have a speedo on my trike.

So several months pass, and I'm thinking a bit more, and then decide that maybe I should put a speedo on my trike.  So I dig and fossick in the shed, and found a speedo with a wire between the sensor and fitted it to the trike.  But the display ended up a long way away from my face and I could hardly read it.  So then I bought 3 wireless speedos from the internet.  They were not expensive and at least one of them works fine, and I can even read it!

And I found out 37kph is quite fast, and I would need to reach 40 with breaking the record.  Most of the time I go around at about 20, and it would take more power than I'm capable of, and more high gears than I have on the trike to go that fast.  Anyway I have not given up completely on trying to get somewhat near the hour record speed, I have started building up another trike from parts in the shed or languishing on trikes I'm not using regularly.  I now have enough to make the trike, and will gradually work on making it faster, an will report on the result.

Regards

Steve Nurse


Fixing A Flevo Part 1

Aki and some of his bikes including the red flevo.  The small bike at his feet is very old and has "Dunlop Atlantic" tyres.


Hi

A few days ago, I went over to my friend Aki's place.  I'd been there a couple of months ago and tried (and failed) to ride his flevobike, and he can't ride it either.  We are both stubborn, and I agreed to pick up the Flevobike at a later date, with a view to modding it so we can ride it.  My plan is to use a set of vuong wheels on the back.  Meanwhile, I am a bit clueless on the dynamics of Flevo's, would it be easier to ride them with a shallow fork angle (seat down) or steep fork angle (seat up)?  I will put this to a forum I have just joined and see if there is any collected wisdom on this.  Regards

Steve Nurse

"Up"

"Down"

Sunday, August 6, 2017

Transparent!

Cutting transparent side panels.....

in the loungeroom.
Fitted to the trike.

Back at Monash Uni, with the source of flashing lights.

The same scene with the lights on, slightly more recognisable as a human powered vehicle.

Hi, for a few years I shared an office with Yun Nam.  Both of us are close to completing our respective degrees now.  For a while I have been fascinated by his motion sensitive LED lights (see this post) and I got to wondering about putting a light show in the back of my leaning trike.  But I had slightly more serious things to think about, and the idea was put on hold.

Recently I saw Yun again, and asked him for some of his lights, and he said sure, take some, and I did.  I bought some transparent floor mat from Bunnings, then stripped back some of the cloth side panels from the trike to get to the timber frames underneath.  These were used as templates for cutting the floor mat. Then the clear sides were attached to the frames,  and the resulting pieces were attached to the trike.

A few days later I went riding on the trike after sticking the motion sensitive lights inside.  I'm not sure that the clear panels could ever be useful useful, but they are useful for showing off the trike, demonstrating that it can carry loads and show off outrageously at night.  I'll mke a film clip when time allows.

Regards

Steve Nurse

Wednesday, August 2, 2017

Cetus 3D Printer cover with pdf plan.

Outside with Printer installed

Inside, thermometer left, cable cutout top, peep hole and plug left

View through the peep hole with thermometer and printer.


Filament Side of Cover
Hi, If you are reading this and don't have a Cetus 3d printer, then you might want to  waste your time somewhere else.  But if you do, then this may be of interest.  The Cetus printer comes without a cover and also does not operate well in cold temperatures.  But if you put an insulating cover over it, the heat from the motors and extruder is kept in, and it can operate well in room temperatures of about 5 degrees C.  

There was a recent contest Cetus ran for the design of a cover, but I can't find the link for that, but anyway here is my effort.  This is a functional cover.  It doesn't put the printer on display as clear covers do, just does the job of holding its heat in and should not be too hard to build.  Here is the web folder containing the pdf plan.

The enclosure is designed with all the corrugations horizontal, and that should help with the heat transfer from the from enclosure: hot air can travel up the corrugations if they are vertical.  Here is a link to the material I used, I got mine from Bunnings. An alternative material would be heavy cardboard, and a recycled bike box (often given away free from bike shops here in Australia, just ask) would be ideal and plenty large enough.

The plan, download it from here


There is an opportunity for Cetus to help there users out here.  If the packaging the printer came in were made for reuse as all or part of a printer cover, or even if they printed a template for a cover on the packaging, it would help users get more out of the printer.  A few years ago I raised a patent for "useful packaging for cycles" which is accessible via the download spec. link here.  Exactly the same principles could apply for the Cetus packaging.

As far as the printer goes, it has worked very well for me.  I'm a mechanical engineer who is finishing a masters degree in industrial design , and since getting the Cetus a few months ago, I have been developing designs on it to help me get into phd studies.  Some of the designs are summarised here and you can follow the link to get to stl files for printing.  Look forward to your feedback on the printer cover design.

Regards  Steve Nurse

Tuesday, August 1, 2017

3d Print Construction Set

2 cubes that can be made with the Tribo parts.
Hi

This page gives some examples and techniques for a 3d printed modular construction set I have developed.  The files to print the set are available for $US 3.00 each from this page on cgtrader.com, and can be used multiple times.  This is the minimum price for cgtrader parts. As an introduction to the kit, you can look at this video, which shows you how to make the cubes shown above using printed parts and 2.5mm bamboo skewers available from supermarkets.

This sampler pic shows how the parts in the set can be connected together, with wooden skewers or with m3 or m4 bolts.  Parts themselves are labelled A, B, C, D, click on the links to download the respective files.

 Here are a few examples of assemblies made with sets of parts A, B, C, D.  In a few photos, I'm including a little bill of material that shows how many of each part are needed.
Dodecahedron, each wooden skewer is 250 mm long.
First crewed rocket to Mars!
Photo Frame Part 1, Assembled frame and adding corflute or cardboard to one side.
Photo Frame Part 2, Add a photo, then add some decorative bling, in this case a few buttons from my wife Christine's Collection.

"Retro TV"
"At the Drive-in"
5 sided prism.
Complex Column Structure. This uses assemblies of seven small triangles arranged in a crinkled up circle as a subassembly and was built after discussions with Monash University maths lecturer Daniel Mathews.


 So that is all I'm going to do for you today!  Here is the video link, please download the files for A, B, C and D, then please print and show me what you've made.   Regards  Steve Nurse,
steve (the @ symbol) modularbikes.com.au