Wanderer Dinghy – Mast Step Repair – Part 1

The Wanderer dinghy – mine at least – has marine plywood cunningly concealed at the lowest point of the boat. The plywood runs from the front buoyancy tank, under the mast step, and to the centreboard case. Sitting at the lowest point of the boat, the wood is often sitting in water. My boat is now 40 years old and poking around in the front buoyancy the wood appeared a bit softer than I’d like. Well – the wood at the top could be pulled apart with my fingers.

The view from inside the buoyancy tank

In addition, my boat has a free-standing mast without shrouds. This is both a good and bad thing. The shrouds help to keep the mast upright, but they mostly try to pull the mast through the bottom of the boat. The wood is obviously designed to resist this downwards pull. However, the free-standing mast has huge sideways forces at the foot and if that foot isn’t really attached to anything strong then this would be a disaster – both for the boat and anyone sitting near the mast.

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Ukulele intonation – compensating the saddle

I bought a cheap Makala pineapple ukulele secondhand on eBay – I couldn’t justify anything expensive. Overall I’m very happy with it – the tone is fine & it holds its tune. However the intonation (tuning) of the fretted notes was poorer than I’d like particularly on the C (lowest and thickest) string.

There are a number of reasons why this can happen:

  • The nut and/or the saddle is too high, so the string gets stretched when you press your finger down. This raises the pitch.
  • The saddle needs to compensate for the thickness of the string. Thicker strings don’t bend and vibrate in exactly the same way as thinner strings so the length needs to be slightly different.

Adjustable compensated saddles are a standard feature of electric guitars and basses providing screw adjustment of the length of the string. However for some reason they are not standard on acoustic instruments – maybe just because of the weight. Expensive ukuleles have fixed compensated saddles but cheaper ones (and mine is very cheap) don’t.

I checked the action (distance from string to fret) at the first fret and the 12th fret and these appeared to be ok – well within the figures given on the websites I found.

So what I needed to do was move the saddle away from the fretboard for the thickest (C) string. This involved cutting back the saddle until the intonation was correct at the 12th fret. Even on a cheap instrument this is a bit daunting.

To make the process reversible I bought a new saddle. I rubbed it on fine sandpaper until it was the right size to fit into the slot. The old saddle could be slid out once the strings were slackened.

Checking the tuning at the 12th fret
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Pineapple Ukulele Case

I’ve recently started playing the ukulele and am loving it. I bought myself a cheap pineapple Makala soprano uke on eBay – it isn’t the finest uke in the world but it does the job and I like the shape. One issue I quickly hit was where to store it – the cardboard box it came in doesn’t really do the job.

No-one sells non-bag cases for pineapple ukes. So I took a punt on a Stagg semi-rigid case on eBay. It didn’t fit but wasn’t too far off, so this post is about how I got it to fit.

My Makala soprano pineapple ukulele in its Stagg case
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Kids longbows

My eldest daughter asked me if we could make a bow and arrow for her. She’d done some designs and wanted to make them.

We watched some videos on YouTube on how to make bows and had a go. The first attempt broke.

Broken bow. Wood wasn’t great and was too thick when I test pulled the bow.

So we tried a different approach. I’d cut down an Ash sapling in the garden a few months ago – we’ve got Ash trees at the bottom of the garden so we get saplings growing everywhere. The top of this was about the right stiffness for a bow. So we cut off a suitable length and started work.

Trimming the side branches with an axe – watch those feet!

There are some key design points to making a bow. Any wood that is weak enough to bend is likely to break, so the idea is to trim the wood in such a way that it is still strong, bendy but doesn’t break.

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Thorn Me’n’U2 Tandem Dynamo Bracket

With the days getting shorter and darker I needed to get the dynamo working again. I had mounted this on a simple bracket bolted to the front panier rack mounts. However the stronger forks for the electric motor don’t have these mounts, so something else was needed.

As an aside I am still a fan of dynamo lights. In the old days (pre Li-ion batteries and LED lights) a dynamo system was the only way to get a usable bike light. These days battery systems are brighter than dynamo lights. However there is a huge advantage in a lighting system that never requires charging, is always on the bike and thus is always available for use even if you didn’t think you would need it.

However, it must be said that on this bike a battery front light is a requirement at night as getting started on a three-seat tandem in pitch black is hard. Without a light you’ve got no real idea which way is up.

Dynamo bracket
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Mazda 6 Sill Trim

My car had a minor altercation with a post in a car-park which resulted in the sill trim falling off.

I know my car is well worn but this is a bit too scruffy

There was also a minor dent in each door plus paint damage.

It didn’t seem worthwhile getting a full bodyshop repair done – the repair would cost more than the car is worth and there are a few other scratches in the paint anyway. But the plastic bit needed to go back on – otherwise the car just looks horrible.

First step was figure just how to refix it. The trim is held on with plastic clips and these were (mostly) still in the car body panels. Some had been left in the car-park so more were going to be needed. On first glance it looks impossible to put it back on as the clips need to slide into the plastic sill in different directions, but eventually I figured out that if you take the clips out of the car and put them into the sill it becomes easy – the side is tapped into position first, then the bottom clips swing up into the bottom of the metal sill.

Next I had to have a good think about whether it would be safe. The plastic sill is large and heavy – if it fell off at high speed it would be dangerous. I therefore decided to replace all the clips regardless of whether they needed replacement or not.

I phoned Mazda parts and discovered that the clips were £5 – £6 each. Ouch. Ordered them anyway, but they delivered the wrong ones. This gave me a chance to get the part numbers and find them on the Internet where they were around £3 for a packet of 10. If you need the information the part numbers for my car (2010 Mazda 6) are:

Side clips: G18K-51-SJ3

Bottom clips: BP4L51SJ3

I bought them from VehicleClips – good service and the clips look very good indeed.

Getting the old clips out is an art. I found a pair of children’s scissors that were flat enough to fit between the clip and the metal panel; I could then squeeze the clip enough to get it out without damaging anything.

Getting a side clip out
The clip once removed showing the bit I was trying to squeeze

Once all the clips were out I could fit the new clips to the plastic sill and bang it into place. This is quick and easy once you’ve got it set up.

To make the metal bits look better I washed down with car shampoo followed by car wax. This filled in the surface scratches making the damage much less visible. Overall you can still see some scuffs, with minor dents visible if you look for them, but it is now OK and a coat of winter grime will hide it all.

Thorn Me’n’U2 Electric Conversion – Conclusions

The motor is now fixed, the speed sensor wire is lengthened and the sensor fitted, and the rear brake sensor is now fitted. We’ve just done an 18 mile ride with lots of hills. How well does it work?

Background

I’m around 85kg, the kids are around 50kg between them, and the bike is around 35kg with the electric motor fitted. Plus luggage. Say 180kg total – quite a lot to haul up a hill.

Most of that weight is on the front wheel.

No more worries about hills

The biggest change is that hills are no longer a problem. I used to be aware of all the hills I would have to climb – not worried but I would always have them in the back of my mind and would choose a route to minimise hills. Now I don’t think about them.

I’ve normally got the power set on 3/5. This is enough to easily climb hills (almost any hill) at about 8mph with low battery consumption. If I increase the power to 5/5 (max) then the speed will increase to about 12-13mph but the battery drops fast.

I no longer use the small chainring at the front – it isn’t necessary. Bottom gear in the middle ring is low enough for any hill I’ve found so far.

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Bafang BPM front hub motor cable replacement part 2

As mentioned previously I used the existing cable – just shortening it a bit. The remaining length is ok and I didn’t need to get a cable through the axle from scratch.

I carefully drew a diagram of the colours of the wires and reconnected the new ends to the correct colour. The soldered joints were covered in heat shrink and self-almalgamating tape.

I didn’t use any glue, putty or sealant. I reused the existing wire ties and added another around the omega clip.

Recut wire soldered in

Note that the wire exits the axle inside the motor on the same side as the aperture on the end of the axle. This means that if the aperture on the end faces downwards, and any water gets into the axle, it will drain into the motor. Whereas if the aperture on the end faces upwards then water cannot get out of the axle into the motor.

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Bafang BPM front hub motor cable replacement

As mentioned in a previous post I damaged the cable for a Bafang BPM front hub motor. I found various instructions on the web for strip-down instructions – notably this strip-down on Endless Sphere.

My motor isn’t exactly the same as any of the stripdowns I’ve seen – mine is a front hub 250W motor without sensors. I’ve put some details here if only for me when I need to do this job again!

The cover plate comes off easily enough and the motor unit can then be pulled out of the hub. Note any washers between the outer hub and the motor unit!

Two shim washers on the non-wire side of the hub

The clutch and planetary gears can be pulled off. The sun gear can then be unscrewed from the motor and the circlip underneath it removed.

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