Tuesday, October 14, 2014

Larger Milan

We have been working on building the pattern for a slightly larger Milan for a while now.  It has languished for quite some time but has seen some work lately while I have been waiting for parts to arrive for  Milans that are on order.   It is a bit taller, about 2 cm at the shoulders and a bit more at your feet.  Most importantly it is longer by 8 cm with the door opening moving forward the same amount.   The limitation for really tall folks in the GT was that if they had really long legs their shins would not clear the front edge of the door unless you moved the bottom bracket further forward.  Short cranks help some for this but mostly you ended up with the bottom bracket too far forward to be in a good pedaling position.   I have also increased the width at the shoulders by 6 cm.  So now if you only just fit in the Quest you will have space in the Milan XL.  Any suggestions for a better name?
Here you can see the extra width at the shoulder.  I have the first side almost done and just need to make more templates to be sure the two sides end up being the same.  
The other side with the template in place where all the fill needs to go.  I have left the shell open just in case I need to add some material on the inside.  I did need to cut some away and fill in the nose to get a nice shape as just cutting the  original apart and rejoining it longer caused a bump to show up.  The orange bit is the modification to add the rain gutter to the mould.  

Saturday, October 11, 2014

Motivation

This ride turned into a long way to go for a couple of beers.  My friend suggested we ride to Powell River to check out the craft brewery there.  Sounded like a good idea.  The weather was nice, the ride is a reasonable distance the only complications being catching ferries and getting back before it was dark.  I left here early caught the 7:00 ferry and met my friend south of Campbell River.  Had a leisurely ride down to the next ferry.   A half hour wait for the ferry, one hour and half ferry ride and just a short ride to the brewery for beer and lunch.  Arrived at the brewery, as cars were parked out  we pulled around the side.  It didn't look very open as we passed by.  In fact it wasn't open but not all was lost.  As soon as we pulled around the side we were invited to help pick hops off vines collected from the local area that were growing wild.   No sooner had we started and we were offered free beer.  A new enthusiastic employee was quite diligent at keeping my glass filled.  After picking hops we were given a tour of the brewery.  Ended up buying some beer and then off for lunch a short way away.  Just barely made it to lunch and didn't need to order any more beer.   After lunch not 100 meters from the pub I had a flat.  Didn't stop soon enough and I ended with three punctures.  After fixing these and using all my patches it was a bit of a rush to the local bike shop for another repair kit and then the ferry.   Getting off the ferry was interesting as I had to rush to refill both front tires which now both had slow leaks.  Rode about twenty minutes pulled over and refilled the tires.  Did this once more and then decided to try for the ferry home as it was getting dark.  The rest of the way was mostly downhill with two smallish uphills.  I was suitably motivated at this point.  Not only was I losing air but there was still an hour of riding to go.  Probably was over 60 kph for about ten-fifteen kms and then over forty most of the rest of the way.  Made it to the ferry with half an hour to spare.  Added more air and made it home before 9 with a total distance of about 140 km.
Link to the brewery  townsite brewery

Tuesday, September 2, 2014

New Front Boom

Have been working on this since last year.  After a few false started we ended up with this.  I have the parts in the mould( the orange thing) for alignment purposes.

So far it seems to be stiffer than the aluminium boom it replaces.  The limitation for stiffness is the stiffness of the shell as the boom has to be attached to it.  Having the rather large "I" beam in the front of the wheel wells should really stiffen up the front end.  The really good part about this is we are saving around a pound.  The bad part is that it will cost more.

A close up of how you adjust the bottom bracket. There are to be four bolts that hold it in place.  One may get away with only using two saving a bit of weight.  Adjusting by two holes will most likely require changing the chain length as every two holes is two links.  The holes are spaced 1/2" apart.  Before coming up with this boom I tried wrapping a foam core with carbon.  That really got out of hand quickly as it ended up being a mess and went in the garbage.  Then I tried making the same thing in a mould but that got quite messy too.  The precision required to do it properly would require a CNC machined mould and a separate mould for the core.  I could infuse a top hat section in the mould and then fill it with foam.  This would take quite a while making it far too expensive.  After some calculations I determined that the carbon/foam one would only be 20g lighter than the wood core and carbon one.  I rather like using a bit of wood as it is nature's carbon fiber and can rival carbon when combined with composites and epoxy.  So what we have ended up with is a chunk of an expensive ski as the boom.     


I have had the bottom bracket shell in my GT creaking some.  After tightening the clamps a few times I finally took one out to see what was going on.  It would go away for some time after each tightening but would be there again after riding some tough hills. Here is a the first attempt at making a replacement and the used clamp.  Upon looking closely at the clamp it has started to bow on the vertical sides.  It was only applying pressure at the top and bottom corners.   I was using a torque wrench to get the bolts evenly tight and getting worried about snapping the clamp.  The first attempt at an improvement, while it works it wasn't easy to install as it has too many loose parts.

This is about version eight.  Only two parts with some flex in the corner.  I can't see why it shouldn't be an improvement unless the hose clamp isn't up to the job.  There are much stronger hose clamps than the ones I am trying out if these fail.

What it looks like installed on the boom.


Saturday, August 2, 2014

Up on two wheels/back on two wheels

I discovered that it is possible to get the Milan GT up on two wheels and recover.  It just kind of happened on a downhill section with an S curve.  I brake a bit before the corner and then just let it run but this time there was a car coming around the corner.  I was close to the center of the road trying to stay away from the crown of the road as it is going the wrong way.  When I saw the car I moved more into my lane and the inside wheel lifted.  I had a quick look around to where I might end up if it rolled and slid but with a small steering correction, all was good.  Where I would end up was in the trees beside the road after sliding on grass.  The velo would have been a mess.   How the rider would have fared isn't too nice to dwell on(probably OK but very pissed off).  Now that I have lifted a wheel on the road you can tell quite easily when you are getting close.  One can feel the inside wheel becoming unweighted so you know when it is time to back off.  I will take this corner a bit more slowly in the future as I must have been close to lifting a wheel before as the left wheel started to feel light.

Back on two wheels of a different sort.  There is more riding to do on the island off road than on, so I now have a new bike.  Never had a bike I could ride much off road before so it is a new experience.  I do need to learn some new skills as the last time I rode an upright bike for more than five minutes was over twenty years ago.   Already fell over twice as a result of a bit of overconfidence riding some easy trails.  More practice required.  The front shock is an entirely composite unit, seems to work quite well and is quite light.  Maybe the basic idea can be adapted to work in a velomobile.   I built a composite rear suspension in the Aurora which works great but is hard to adapt to a tadpole configuration.   Putting both ideas together and building a prototype to try it out may happen once I have some spare time.
Building the pattern(plug) to create removeable foot(heel)covers for the Milan SL.  I laid up some material to mimic the thickness of the foot hole covers and now need to make it all smooth and shiny.  If you remove the foot(heel) bumps from the SL you increase the ground clearance considerably.  I had to tie some kayaks on a new car the other day and ground clearance for the car was about the same as the SL with the heel bumps removed.  Considering that the wheel base of the car was longer the SL may have more clearance.  I noticed that on the front bumper of the car there is a rudder strip that hides the scrapes under the car's front. With the heel cutouts you also get reverse back without opening the door and using your hand on the ground.  This works for me but for shorter folks this may not be an option.  You also get more ventilation with air coming in the foot holes. 


Wednesday, June 25, 2014

Monocoque or Hybrid??

Here is a photo of the structural reinforcing bits that go into the Milan SL.

The wheel well is in velomobiles with enclosed front wheels.  The other ribs are sort of borrowed from boat building where stringer systems are quite common.  They are made from two layers of carbon with some extra reinforcing and then secondarily bonded into the shell.  I have thought of infusing the parts with foam ribs but by the time you add in the weight of the foam you are at about the same weight as the bagged parts and secondary bonding(hollow ribs).  I have a bit more freedom in shaping the ribs with my present method.  The long S shaped rib could be shorter but the added 70 g or so is a worthwhile addition in stiffening the panel. 

I finally brought my Garmin along on one of the Wednesday night rides.  The ride ended up being about 50 km long with about 700 meters of climbing with an average speed of 26 kph.  I am faster when there are other riders along it seems.  Riding by myself doing the same sort of ride would be 3-4 kph slower. The first and last 5 km are slower than the average as I ride to the start and then back home again.  One interesting thing I noted was that the velo climbs better than an upright bike if the grade is low enough.  I'll keep track of at what sort of grade and speed at which this happens.  If it gets too steep like about 5% or more the extra weight of the velomobile really shows up.   One of these weeks we will do the Wednesday night ride out of Campbell River.  I am looking forward to the flatter terrain and smoother payment.   

Friday, June 13, 2014

Miscellaneous Musings

First off a new rear cover for the rear wheel openings in the SL.  It took a while(three tries) to get it right. Delayed a couple of times by other stuff that needed doing but now we just need to sand and polish the modified part of the mould.




Hiding the tent away inside the GT or even the SL.  It fits very nicely in the turtledeck.  I stuffed the tent in separate from the fly but with a a bit more practice getting it all in would be pretty easy.  The poles and pegs fit up there too. What would work even better would be a new more compact tent.  New ones can be about half the volume.  Our tent is a good sized two person unit of an older vintage.



Tank vs central U-joint steering.  After having installed a few tank steering units in the GT and SL I can completely understand why, from a manufacturing perspective, central U-joint is the preferred system.  I have been trying to train myself to be good with either one but I just like the tank one better.  About 10-15 kph faster with the tank steering before things get uncomfortable.  I'll keep working on getting better with the central U-joint one.  The training process with the central U-joint has improved my steering with the other system.  Now I have to be more careful as it is too tempting to just let it run.  There are a few spots on the downhills here where you really should check your speed.   The rough road here encourages that anyway but you can still overdo it for the conditions.  I would much rather build new velos than fix built ones!!!  The one negative on the tank steering is that the levers take up some storage space.  In the picture you can see that it isn't all that much.  About a water bottle's worth of space but still with room for a bag beside the levers. What would be really handy is a foam shelf for small items just beside the levers.  It could be stuck on with Velcro so you can fine tune its location.


For the good, fast crowd, one could add a clear fairing to the back the the mirror fairing to clean up the aerodynamics around the mirrors.  A camera in the tail and screen would be even more aerodynamic but I really like the simplicity of mirrors even if they slow you down a bit.  I use them a lot and feel very uncomfortable without them.  Even having just one doesn't seem enough.  I would put having a mirror on each side onto the list of essential safety equipment.

Saturday, May 31, 2014

Best Ride Ever?

Well maybe not quite but certainly right up there.  There is a Wednesday night ride on the island here.  I have been taking part most weeks using the Milan SL, Milan GT  or my high racer.  Lately it has been the high racer but this week it was the Milan GT.  It ended up being a great choice for this ride for some not so obvious reasons.  The folks on the ride have been threatening to go north for some weeks now.  Going north is the most hilly and twisty paved road on the island and definitely the most velomobile unfriendly ride.  First one out onto the road decides where we will ride.  This week there was lots of milling around before someone finally turned left or right.  We turned right and then right again after the store so we were heading north.  The first kilometer was OK just some rolling terrain where I was out front but this wouldn't last much longer.   I was already braking a bit on some of the turns as I didn't know this section too well.  Several times the faster folks almost caught up but the terrain was just in my favor.  Then it started to go uphill and everyone passed me.  I almost caught up again but was reluctant to just let it run as the road was fairly twisty.  Time to just enjoy the ride and slowly pedal up the hills.  The sun was shining thorough the trees and it was a lovely evening.  Riding up wasn't so bad just take your time and look around.  I had only driven this section before and you don't see much at car speeds.  All the different greens at this time of year are remarkable if you only take the time and look.  After climbing the first big hill there is a very steep descent which had me on the brakes most of the time.  I was thinking that maybe I should just turn around and head back rather than have to climb back up this and more.   I kept going and met the group just after they left the turn around spot.  On the way back there were a couple of spots where it was impressively steep where forward speed was very low.  The group waited just before the last big descent and we all took off.  I was near the front and let the three or four fast guys go first.  I was on the brakes quite a bit.  Most impressed with how the GT handled the curves.  I could stay with upright bikes on the corners until I chickened out and braked.  No issues with braking at speed with tank steering as I had practiced at bit previously.  It was a good thing to have the tank steering as I was applying quite a bit of force at times.  So much braking that the next morning my hands were a bit stiff.  At the end there was a straight bit down and then up to a stop sign.  I couldn't resist finally shifting up to the big ring for the first time on the ride and going for it.  Short but quite fun to zoom by folks in their tuck like they were standing still.  Had to brake hard for the stop sign.