Monday, 24 June 2013

Gear Range % Cassette vs Hub Gear

Gear Range % Cassette vs Hub Gear - Intro

I have found it tricky working out how much range I will loose by switching to a hub gear from a 1 x 9 set up on an mtb. Sturmy Archer and SRAM express there gear hub range as a percentage. You can use my gear range calculator spread sheet to work out your current gear range it also includes some gear range percentages for hub gears.

Gear Range % Cassette vs Hub Gear - Comparison

Gear Ranges of some Hub Gears

Sturmy Archer 3 Speed = 177% Gear Range

Sturmy Archer 5 Speed = 256% Gear Range

Sturmy Archer 8 Speed = 325% Gear Range

SRAM 2 speed            = 136% Gear Range

Nuvinci                         = 360% Gear Range

Rohloff                       =  526% Gear Range

Gear Range of Derallier drive Trains

1 x 9 (11-32)            = 290% Gear Range

1 x9  (11 -34)           = 309% Gear Range

1x10 (11 - 36)          = 327% Gear Range

3x10 (Typical)          = 550% Gear Range

Gear Range % Cassette vs Hub Gear - Summary

Unless you want to spend of fortune on a NuVinci or Rohloff, you will not beet a typical 3 x 9/10 derailleur setup. Good ranges can be had from a 1 x 9 setup which provide simplicity of operation with ranges that better most lower end hub gears.

You can use my gear range calculator spread sheet to work out your current gear range it also includes some.

Other Gear Calculator 

Great write up on hub gears

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Friday, 21 June 2013

How to Build a Garden Office

How to Build a Garden Office - Intro

In this post I aim to describe how you build a fairly shabby, but well insulated garden office for under £1000.

Before you start draw a plan of you office on a bit of paper, and work out how much wood you will need and make sure you have enough space for everything you intend to put in the office. See my garden office plan.

  • OSB and Plywood Cladding
  • 4" x 2" (100 x 50) framing
  • Knauf acoustic role insulation 100mm.
  • Reclaimed upvc double glazing units.
  • Damp proof floor
  • Sedum roof.

How to Build a Garden Office - Choosing Your materials


Perhaps the most important consideration is cost, a green roof is cheap and 10mm shuttering ply board is also cheap which is why I have opted for them. where you buy your timber can make a big difference. All my timber came from Travis Perkins, which came out cheapest when I quoted around.

Other more attractive external and internal cladding materials might be considered such as ship lap, or taper cut or external tongue and groove.

A garden office built with ship lap timber.
shuttering ply - not as pretty!
Despite not being very pretty ply wood as an exterior office cladding has two main advantages:

  1. Increased weather proofness- unlike building with ship lap you will not end up with loads of little cracks which wind and rain can get in to the garden office.
  2. Quicker - 1 bit of ply board will cover 2.88 m sq. so you will be working a lot quicker than you would with ship lap or taper cut.


If you intend to work in your office over winter you will need to insulate it, unless you want to run up a large heating bill. 100mm of insulation is good, rolled mineral wool if you are on a budget, if you can afford some rigid foam board or XPS then lucky you. Don't forget insulation can keep you cool in summer too, and keep out sound. I went for acoustic insulation for my garden office.

How to Build a Garden Office - Step 1 - Footings and Floors

Floor Structure for your Garden Office

First off clear a patch of ground big enough for the garden office to fit in, clear of weeds etc, and then use a spirit level and a plank of wood to establish 4 or more level pads (concrete blocks / bricks) on which we will start to build our floor structure. Check the floor structure is square, place an uncut play board on top and use it like a giant set square to check that the office base is square.

the foolish pig?
Remember to make a good job of this stage, even a cheaply built garden office will be fairly heavy come the end. Pads every 1.5 meters is a good idea.

Damp Proofing Floor of Garden Office

Next lay down the cross beam / floor joists , and over lay with damp roof membrane.

space your joists to match your uncut ply board / OSB (saves time)
Insulation and Floor Boards for your garden office

Trim the damp proof membrane around the edge of the floor platform, you can leave this until after puttting down the floor boards, if you want. Then add in the insulation to fill the voids between joists.

 Building a Garden Office - Step 2 - Walls

To build the wall of you garden office you have two choices you can either build the frame for the walls and then attached the external cladding first. Or if in my case you are building close to a boundary the you can make up individual panels with the exterior cladding already attached.

building with panels as above is good when you are in a tight spot

 Things will be a bit wobbly to start off with but once you have made you first corner, things will become easier. Keeping checking that everything is upright using a spirt level.

building a corner means a stable wall section to work from
Extra framing around windows
 Doors and windows for your garden office.

Windows and doors can be sourced fairly easily from ebay, second hand is cheap expect to pay £15 - £50 for an ebay window, or £150 - £350 for a new window. Double glazed will keep the heat in better.

Buy a timber door frame and build this in to the garden office to provide access (hanging the door is probably the most technically demanding part of the whole build!)

Building a Garden Office - Step 3 - Roof

Building the roof is almost the same a building the floor, just put it on top of the garden office, leave an over hang all of the way around so that drips don't run down the walls.

To water proof my roof I used 3 layers of damp proof membrane, get on the roof, with no shoes on, unroll the plastic sheeting over the roof, staple down around the edges. Not easy doing this when windy so try and do it on a calm day.

Inside you garden office

Inside why not make your own desk and shelves with off cuts / spare wood. Cheap and made to measure.

ready for work

OK that is it. In our next post we will observe the set up for the DIY green roof.

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Wednesday, 19 June 2013

Fix Broken Panniers

Fix Broken Panniers - Intro

I have had the same set of panniers for about 5 years, and so I was a bit upset (boo hoo) the other day when one jumped off and wedged its self between the pannier rack and rear wheel, partially destroying my mudguard, and some of the clips off of the pannier. The damage to the bike was not too bad, but most importantly I was lucky to stay under control of the bike.

So the fix here we are dealing with is the fixing mechanism (bag to bike) rather than sewing a tear or similar.

In this post we are replacing the hooks / clips with a home made alternative.

Fix Broken Panniers - What you need.
  1. A piece of thin ply wood.
  2. Some nuts and bolts.
  3. Some Builders Fixing Strap 
  4. A Drill
  5. A saw
 Fix Broken Panniers - Lets Go

First off cut the plywood to fit in side you pannier, you can just about see it here. This give rigidity to the top portion of the pannier, and gives the bolts something to bolt too. Then decide were you want the clips to go (as close to the originals as possible?). And then drill holes right trough the pannier and the play wood.

Or perhaps the picture below is clearer.

On the other side make some "U" shapes out of the builders fixing strap and then from the inside slide the bolt though the ply wood, bag, bag fixing strap, and then put the nut on and tighten up hard. As you can see I have use some bits of handle bar tape as padding against the rack.

The result.

Good luck. I will answer any question if you have any. Just post in comments below.

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Fitting Disk Brakes with Mudguards

Fitting Disk Brakes with Mudguards - Intro

Mudguards stop you and you bike getting muddy and wet, and disk brakes provide a method of braking that doesn't wear out your rims, and pads last longer than rim brakes between changing. This makes the two add-ons a good choice for the practical biker, but unfortunately it is not always a straight fit. I will explain ways to get around the fitting problems associated with fitting mudguards and disk brakes on the same bike.

Fitting Disk Brakes with Mudguards - Solution 1 - Choose the right brake.

Some disk brakes will fit on the bike in such a way that they do not get in the way of the mudguard stays. For example I have fitted some 180mm BB7s which would have fitted without any tinkering with the mudguard stays. Perhaps larger disk rotor are the solution as the callipers are usually mounted higher up.

Fitting Disk Brakes with Mudguards - Solution 2 - Bend Your Mudguard Stays

On fitting some Clarks CMD-8 Mechanical Disc Brake I found that the callipers got in the way of the mudguard stays. you can get around this by bending the stays using two pairs of pliers (one to hold, one to bend). Depending on the amount of bending done will mean that the stay has to be longer then the one on the other side, or you could bend the other side to match!

Fitting Disk Brakes with Mudguards - Solution 3 - Lose the Stays

If you have a rack, then why not attach the mudguard to the rack at the furthest point back, and do away with the mudguard stays all together.

To do this you will need some kind of bracket, I used a length of builders fixing strap, and some nuts and bolts and washers.

You simply drill 2 or 3 holes in the top of the mudguard, and then bolt the bracket, strap to it, then bolt the strap to the mudguard. As you can see my mudguard got snapped off owing to a pannier falling off. This method would work better with some 3/4 length mudguards.

All the best.

Monday, 10 June 2013

Algal Bloom South Devon Coast 2013

Algal Bloom South Devon Coast 2013

The last two weeks I have visted much loved snorkelling locations on the South Devon Coast. Namly Blackpool Sands and Bigbury on Sea / Burgh Island. The water is murky and not as clear as usual.

At both sites there has been severly reduced visability cuased by Algal Blooms, apraently these are harmless, although annoying . Visiability is reduced to around 1 feet in places with a maximum visability of 3 feet.

Comments of 2013 south devon algal bloom from EA officer.

More on the particular type of algae caasing the blooms.

Update 08/07/2013: A return trip to the south devon coast this weekend saw the that the bloom had nearly gone, with visability far better although not as good as it could be.

Conclusion: The bloom in this instance had a lifespan of around 4 weeks.

On the 13th June the EA published this article.

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Wednesday, 5 June 2013 / Model Rocket Shop Review / Model Rocket Shop Review - Intro

I really didn't want to buy my Dad a pair of gardening gloves for his 70th, so I bought him a rocket instead. Bought it from the boxes have to go by courier becuase of the explosives, so postage is expensive.

The stuff tuned uop on next day delivery is exactly as it should be, I got email saying when it was being dispatched etc.

If all interent shopping was this easy I would be a happy man.

Thank you very much, will be back for spares etc. / Model Rocket Shop Review - What I bought

I bought a kit with two rockets, three motors and launching equipment, the rockets chosen are ready built and require no assembly so dad can fly them on the day.

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