The Year of the Caravan

This year the caravan will finish! Well, finished enough to be in use. I'm not sure it will ever really be finished. Already I have a list of fixes, changes and improvements. But not now. The focus is on getting it done. Changes can happen later.

December was looking promising. I had lined up time with my welder friend to get some chassis fixes done. The brake caliper mount. Strength the draw bar attachment. Make the disk brake handle mounting seen in the previous post. I also lined up another friend to help with the electrical wiring. The best laid plans of mice and men often go awry.¹ I caught COVID. There are no quarantine rules anymore, but I wasn't going to share the infection.

I did end up getting the welding done. And over the Christmas - New Year time, got the disk brakes mounted. The cabin got another coat of paint on the outside also.  I've still more to finish and look forward to the Men's Shed reopening.

The delay for the electrics turned into a good thing. It was going to be two ebike batteries: one on the ebike, one in the caravan. Charge the one in the caravan, swap with the ebike when required. But the caravan battery needs to provide power while it is charging. The BMS in the battery I have doesn't allow that. If it is charging, discharge stops. A work around was to charge it via the discharge port, but I wasn't keen on that solution. I thought to have a small 12v battery for caravan supply, and charge that from the ebike battery or solar. Eventually I decided to have the caravan just use a 12v battery and skip the second ebike battery. I'll charge the ebike battery when I'm stopped. 

Well, that's the plan.

¹: https://www.dictionary.com/browse/the-best-laid-plans-of-mice-and-men-often-go-awry

Brakes

Been thinking about brakes on and off for as long as the caravan has been going. A lot of the European caravans use inertia brakes. I wasn't keen on that option, preferring to have direct control on the braking. Some of the caravans had no brakes. Madness! I can't think of a time when you'd think "Gee, I glad I don't have brakes!"

So, I need to activate two brakes on the caravan from the bike. And it needs to be able to disconnect. I've flip flopped between mechanical and hydraulic, one lever or two. Even considered electrical. Stressed over if one or two cables from the bike all the way to the caravan wheels would be able to activate brakes. Would there be too much play in the system? Do I need a booster system. Do I need pulleys in places to smooth the action? 

I decided to use hydraulics at the calipers. Mainly to avoid having to adjust them. So then it turned into how activate them. One lever to activate both? They do make such a beast, but besides the eye watering price tag, I didn't find any quick connectors for bicycle hydraulics.  So have to use two levers.  I did consider making new levers, but using the existing levers would be simpler for the future. 

The previous post with the caravan hitched to the bike was to see how much clearance there was for the brake lever mounting. Heaps of space. phew!!

Deadlines focus the mind. Tackled the brakes. Cobbled together this test setup. Dowel, wood clamps and scraps.

The full test setup for dual brakes from one lever

I used a kids cart brake lever and cable. The garden rake had the right handle size to fit the brake levers on.

Close up of the cable to lever (front)

Some scrap metal with the right size hole for the front. Adjuster is needed to tension the brake cable. There is one also at the lever end.

Close up of the cable to lever (back)

A lucky piece of aluminium with just the right bend in it for the back. I don't think my test would have worked so well if it was flat. I used an old V-brake to pinch the cable so it wouldn't pull through.

Levers mounted on dowel.

It worked! Very happy with the it. A few refinements will be needed for the final design. Needs more clamping. The cable could jump off too easy otherwise. The final will be out of aluminium rather than wood.