Playing the waiting game.

I have just dropped off the frame and cargo box to get fully tig welded by professionals as my welding skills are not what you would call great and while I can happily tac it all together I want it to stay together.

Hopefully in a couple of days... depending on how busy they are, I will have the frame back ready to assemble into a semi finished state.

Whats left to do?... lots.

Clean up/remove any unwanted or extra lugs off the frame or excess welds.
Design and build the axles for the front wheels including the disc brake mount and steering arm that comes off the axle.
Shape and drill the steering tube mounts... top and bottom.
Finish cutting and fitting the base plate.
Clad the exterior of the cargo box.
Powder coat or paint the frame and cargo box.
Design and build the light system.
Plus a few things I've probably missed!

Back in a few days with an update.

Steering tube attachment and final back half prep.

I got to spend another couple of hours in the garage today and thought I'd finish off a few things but grinding out the joins etc takes time and a lot of it when its not something you do everyday so I didn't quite get as much done as I hoped.

I woke up thinking about the steering tube attachment this morning... should I weld it to the front half or should I stick to my original plan to bolt it on giving me the added benefit of being able to dismantle it into 2 smaller pieces.

After pondering over it for a few hours I decided to carry through with the plan of bolting it on... for now anyway. I bent up some 3mm steel plate into an L shape a few weeks back with this in mind and had a 38mm hole drilled in each for the steerer tube to fit through and to get welded to. Each L section at this stage is going to be held on by 2 x 10mm bolts... so 4 x 10mm bolts in total. The L sections are going to be hand shaped and will be drilled to house the cable for the front brakes.

This photo is from the inside of the cargo box.

I managed to cut/grind and get the "down tube" ready to tac into place.

A few more bits and pieces.

I had the time today to do a few more wee bits on the trike, namely the head and steerer tubes, and finishing off the back half of the Giant frame cutting and grinding getting it ready to weld with the head and down tubes.

Not perfect but it will do.

Progress is steady at the moment.

Head tube and Steerer.

Ready to attach.

The front cargo box assembly.

I have moved onto assembling the cargo box and the list of materials i'm using is below...

22.2mm x 1.2mm square tube steel... for the frame
3mm steel plate... for the mounts for axels etc
38mm x 2mm round tube... for the head tube and down tube
28.6mm round tube... for the steerer tube
4mm Alloy checker plate... for the floorpan

I started by drawing a scale floor plan on the garage floor. I cut and laid out the square tube base and welded the tube into place checking that everything was square and true. After double checking all the measurements and alignment I preceded to create another to the same dimensions for the top.

Looking around there were a lot of different heights/depths commonly used for the cargo boxes but I choose to go with a 550mm so I cut the uprights and squared them up and welded them in along with a bit of bracing for the base.

Which wheels are best for the front?

Now that I have made a decision on the cargo box size/shape it's time to move onto the 2 front wheels.

There are a few considerations when it comes to the wheels and they are as follows.

What size?
20" 24" 26"?
What hub type?
What braking type?
Disc or Rim?

After looking at most of the varieties of cargo trikes out there 20" seemed to be the weapon of choice as they offer great strength. The christiania trikes have successfully moved from a 20" to a 24" wheel without any hassles and very few offer 26" wheels.

The biggest problem as I understand it is the lateral loading when cornering, a good set of 20" wheels handle this well and a lot better than the 24" wheels and your standard 26" wheel is likely to fold over. Being that I'm over 6ft I really would have liked something up front that was a bit bigger so I didn't look like I was riding a child's bike.

I toyed with the idea of building up a super strong set of 26"mtb wheels for the front, maybe using some downhill rims etc as weight is not that much of an issue, but after talking to a few engineers (when buying the steel tube for the bike) I opted for the safer more robust option of the 20" wheel size... for now anyway :)

Wheel size sorted, moving along. Hubs and brakes kind of go together, if your using mtb hubs laced to bmx rims you can use disc or rim brakes as opposed to a bmx rim and hub which unless you make or buy an adapter here http://www.atomiczombie.com/DIY%20Parts.aspx  you can only use rim brakes. From the start I wanted to use disc brakes on the front due to having a few sets in the garage already and as I intend on using the trike in all weather I wanted the safety of running the disc in the wet, especially with the extra weight up front. 

So I thought I'd give the mtb hub laced to bmx rim a go only the standard 9mm QR was probably not going to cut it so I've gone for an overkill and am using 20mm mtb hubs.

                                     

Alex 303 wheel and standard hub... Before

Alex 303 rim with a Shimano XT 20mm 32h centerlock disc hub... After.

I was lucky in that the spoke length was correct for the new hubs given that they are slightly taller but also slightly wider. 

Next on my list of things to do is to start assembling the frame.

Turn the box or just the wheels?

As mentioned in the last blog I thought I'd go over a few of the reasons why I went for this particular design.

I guess the main factors to consider were... 
Practicality, stability and simplicity
How well the design works on the road(of which I can't test)
And last but not least how it looks

Seeing as though I have never ridden or even been up close to a cargo trike I can only loosely base my decision on others reviews and their experiences with them, along with my own ideas and thoughts on how these things might work in reality.

As I intend on putting my son in the front and tootling him around town, stability, safety and handling were probably my number one concern followed by cargo space and looks.

I really like the simplicity and squareness of the Haley and Christiania trikes and they seem to glide around corners, even though the weight shifts with the box but the main reason I choose the Nihola style was because of the weight staying centralised and that hopefully translating into a more stable ride... providing I can get the steering geometry correct that is.

Because the style I choose requires the wheels to turn, to get a half decent turning radius the wheels have to be spaced a reasonable distance from the cargo box it'self or at least have the room to turn, so this in some way affects the size of the cargo box. The Nihola has over come this by having the front and rear of the box tapered to allow the wheels to turn in without rubbing against the side of the box. 

So I am going to mix the squareness of the Christiania and the tapered style of the Nihola.

This is using 22.2mm x 1.2mm square steel tube, the length is 900mm and the width at the widest part is 700mm.

What next?

Up until this point I thought I had done a reasonable amount of research on the various types of cargo trikes and ended up having more unanswered questions than when it started... typical.

How much cargo space is too much or too little?
What type of pivot? 
What size wheels for the front?
What type of steering?

And for each of these questions there were five more and then 10 more, hmmm and then came what about or what if?

I felt like I was going backwards, so...
                                                            I started with one fundamental decision.

Cargo space... I wanted to be able carry my son home from daycare along with my work gear and his bag plus a couple of extra bags for good measure. I grabbed some chalk from my sons blackboard and started drawing an outline of roughly 900mm long x 700mm wide and what do you know there's plenty of space for all that and more. So with the cargo box at roughly 900mm long and add to that the length of the bike frame the overall length would work out to be just over 2m. I'm happy with that.

On to the next decision or so I thought, I hoped everything else would just flow on from there but alas no. You see the pivot or steering type and wheel size are all connected in one way or another and that's where I found it difficult to make a decision.

Do I want to turn the whole cargo box like the Haley http://www.haleytrikes.com/ and Christiania http://www.christianiabikes.com/ or do I want to keep the cargo box centered and turn the wheels like the Nihola http://www.nihola.com/ and Carryo http://www.carryo.info/de/carryo-bikes

I pondered this for a good four or so weeks before committing to a decision, weighing up all the pros and cons for each style/design. (I'm about 8 weeks into the build since making the decision to build and not buy and at this time I'm writing the blog in a sort of catch up fashion).

As you'll see further down the track I have opted to make a keep the box centered and turn the wheel type... what these are called I have know idea?.

Tomorrow I'll go over a few of the reasons why I went for that design.