Thursday, 27 November 2008

Loosing your tools

Even those with the tidiest of workshops sometimes misplace or loose their tools. You are distracted by something else or forget to put it away and when you come back you just can't find it. You can of course mitigate this problem by having a proper place for things and ensuring you always put things away at the end of the day (even it your dinner is getting cold).

However life is not so straight forward for astronauts. Whilst cleaning grease off her gloves, mechanical engineer and seasoned astronaut Heidemarie Stefanyshyn-Piper let her toolbag slip and was forced to watch as the tools (apparently worth £70,000) float away. Astronomers from around the globe have the oppertunity to try and spot the toolbag but I'm not sure they'll be able to do much to help if they see it.

Heidemarie Stefanyshyn-Piper Daily Mail Science

Read more about space at the bbc

Tuesday, 25 November 2008

Bicycle Repairshop

Monty Python's Bicycle Repairman

Quite rightly, the Monty Python team saw the bicycle repairman as a hero. One such hero works under the railway bridge by Embankment tube in Action Bikes with this wonderful workshop.

One of the things I like about bicycle repairing is that it has a lot really specialist kit such as spoke spanners, pedal pullers and chain tools. Whilst I was at college I got quite good at repairing bikes and in the process collected a range of such tools and spent some money on some good spanners which I still have to this day.

At college I had a really cheap raleigh bike, bought from brick lane with a single gear and freewheel, less to break and less to be stolen. After leaving college I stripped the bike down and cleaned all the parts. I asked the bike shop in Bath (also under the railway) to respray the frame and also to put a hub gear onto the back wheel. That bike in it's new racing green livery was put to good use by my father for a few years.

The bottom bracket bearings on my racer took some punishing on the hills around Bath. So these were changed a few times and that's one area I got to know quite well. One tip is rather than using the ballbearings in a cheapo ballrace to remove them from that and add an extra ball. Pack them in with lithium grease to hold them in place whilst you tighten up the bracket, you will get a lot more use out of them without the race. The race has a tendency to break up after time and then grind the bearings down rapidly.

Because they are used outside, bicycles are exposed to the worst of the elements so I also got good at removing crud from them and keeping them rust free. If you are a fair weather cyclist then it's definately worth spending time cleaning down before you pack your bike away for the winter. You can also partially disassemble the bike to save on precious storage space.

Sunday, 16 November 2008

Dave Denker's Metalworking

Retired sheetmetal fabricator David Denker from Minnesota got into machining in 2003 when he bought a mini-lathe. He also decided to build a mini milling machine from spare parts and custom made components.

Since then he's been thinking up improvements to his equipment and has completed many metal working projects including:

Low Speed Addition
Gear Plate Change
Tailstock Change
Ball and radius cutting
Indexing head
Bottom up knurling tool

Friday, 14 November 2008

Welding Projects

One of my work colleagues mentioned that he had a "arc welder" that he'd bought because he'd like to be able to weld. Perhaps he'd been watching flashdance that week or perhaps he'd had more charitable thoughts on his mind?

Helping People in Peru by Welding

I did see a nice project of an Armillary Sphere in the Machinst's Workshop magazine Feb/March 2008 that would also require you to have a slip rolling machine to form the metal strips into the circles required for this project. Machinst's Workshop magazine is from the USA but can be bought via importers such as Camden Steam or via subscription.

Unfortunately this issue is common with a lot of welding projects in that you need quite a bit of other tools to complete them. Some essentials would be welding clamps and safety gear such as gloves and a mask. You might be able to manage small fabrication projects using iron wire to hold the parts together rather than using clamps.

My colleague also mentioned that he'd be interested in something ornamental for the garden. Perhaps a weather vane might be a good starter project?

Welding Magazine
Association Of Welding Distributors
The Welding Institute

Mig Welding Forum
Welding Projects Forum

Arty Projects
Ideas Gallery
Weekend Welder

Wrought iron table plans
Welding Table

Welding projects for the more adventurous
Boat Trailer Box
Build your own shepherds
Welding Projects

Wednesday, 12 November 2008

Chemical Safety in the Workshop

I was discussing the issue of storing dangerous chemicals in the workshop the other week with a work colleague and he took the attitude that as soon as his kids could walk he took everything out of the garden shed and outsourced all such activities (such as fertilising the lawn) to professionals. Victor Deeb on the other hand took the opposite extreme view and thought it a good idea to keep "over 1,500 vials, jars, and bottles of chemicals" in his basement and garage and in Birmingham a shed full of acetylene and diesel caught on fire requiring the neighbourhood to be evacuated.

The sensible approach is somewhere between these two extremes, it is possible to keep and use chemicals in your workshop and also keep yourself (and others) safe.

You might be surprised just how many dangerous chemicals you have in your workshop. Here's my quick shortlist. Many of these items will are common in all households but a few are old used for model engineering.
  • Cleaning Materials
  • Pickles
  • Solvents, Polish and Paints
  • Fluxes
  • Gasses - Propane/Butane/MAPP Gas
  • Oils and cutting fluids
  • Fuel

What are the kinds of problems you might get with these materials and what can you do about them?
  • Flammable items
  • Caustic items
  • Reactions
  • Sunlight
  • Changes in temperature
  • Water
  • Storage
  • Poisoning
  • Bacterial contamination of fluids
  • Animals
  • Disposal
  • Quantities
There are many flammable items in the workshop, some are flammable by design such as matches, firelighters and fuel but others such as solvents are also flammable. When not in use you need to keep such items stored out of possible contact with sources of sparks (such as a grinder), out of the sun and well sealed so that they don't evaporate.

Caustic chemicals include cleaning chemicals, acids used for pickling, and fluxes. You need to be careful handling these to ensure you don't get them on your skin or in your eyes.

Some materials are reasonably safe on their own but when mixed can become significantly more dangerous or will react generating heat or rapidly expanding in volume. Hence it's important not to mix chemicals when storing or disposing of them.

In the same way that some materials react with each other, they might also react with light. Sometimes they just "go off" for example if you use nut oil for heat treatments but they may also expand or explode as the summer run heats up that can of petrol for example.

Ambient temperature changes may have a similar effect to the sun. You also need to be aware that if your workshop temperature drops below freezing then any water based liquids stored in bottles will expand and might cause the bottle to smash. Often this issue is not spotted until the liquid thaws out again.

Water by itself is not too hazardous however some powdered chemicals can react with water, particularly if it is not pure (e.g. rain or flood water). You also need to be aware that water might soak through cardboard boxes. Water poluted with chemicals can seep into the ground and cause additional hazards to either you or the environmemt.

Given these above issues, your storage needs to be suitable for the chemicals being stored. A secure, fire retardant, light proof cupboard or box is recommended. You need to ensure it is not going to be flooded or rained on. The cupboard should be vented so that any fumes dissipate rather than build up. Any containers or pots should be clearly labelled as being chemicals rather than being labelled as "Jam" or "Cola".

Label your containers appropriately

Apart from the kids mistaking your bags of flux for sherbet dips there are several other ways people can be poisoned by chemicals. It's also possible to inhale dust, spray or gasses or absorb the chemicals through the skin or through cuts. Transfer of chemicals from the hands to mouth is also possible. Appropriate safety gear can reduce risk. Hopefully you'll research your chemicals before you have problems but the NHS recommendation is to ring 999 in any suspected poisoning case, try to get the following for them:
  • what substances you think the person may have swallowed,
  • when the substance was taken (how long ago),
  • how it was taken (for example, swallowed), and
  • how much was taken (if known).
One problem that can occur in a machineshop is that the your cutting/cooling fluid gets contaminated with bacteria. This can then be ingested when it sprays up when machining or via transfer from hands. Symptoms are like those of a cold, but they may not go away. Don't leave water based cutting fluid "made up" for long periods of time or store it in open containers. You can also get additives to suppress growth of bacteria.

In the same way that you don't want your family to be poisoned, you don't want pets to affected. Storage is key here, remember that paws are smaller than hands! You also want to ensure that your storage is secure from rodents or bugs that might feast on the chemicals.

Your local council should be able to help with disposal or recycling of used or surplus chemicals, see the link below for more details and ideas.

My final thought is that all of the above issues become less significant if you have less chemicals to start with. Do you really need 12 different kinds of flux? Do you need 100L of cutting fluid if you only make watches? If a supplier only sells in bulk then see if you can find some people at your local model club who can split an order.


Monday, 10 November 2008

World's first Stirling hybrid electric car

Deka Research have build a small prototype hybrid electric / stirling engine car based on the chassis of an old Ford Think.

The advange of the "external combustion engine" is that it can be powered from many different fuels without the need for any conversions. Spare heat from the process can be used to heat the car and defrost the windows which are two tasks that normally have a big drain on the battery.

Dean Kamen, owner of DEKA is in discussions with Norway. The Norwegians are not shy of alternative technologies for their cars, they currently manufacture electric cars in Oslo and also import electric cars from India. They used "wood gas" for powering their cars in the 1940s when oil was scarce. However they do ban car salesmen from calling such cars "Green".

Friday, 7 November 2008

Miniature Engineering

In the process of looking for information about making my flea circus chariot I've tracked down a few other people who like to make small things. Charlotte and Martin Willmott made the papers recently with their models of tiny kitchen tables laden with food.

Charlotte and Martin Willmott's Tiny Table in the Telegraph 28 October 2008

Laurence and Angela St Leger makes miniature automata approximately 1 inch tall powered by the pull of an almost invisible wire or a tiny crank.

Tiny Executioner by Laurence and Angela St Leger

Award winning model engineer Cherry Hill makes some very small components for her 1:16 scale working traction engines. Often this requires making tools that in themselves are smaller than a 20p coin. Details of her workshop can be seen in the Model Engineers Workshop Special Autumn 2008.

Worm and pinion gear made by Cherry Hill

Other Suppliers of Miniature items

Tools for miniature modelling

Clock Makers

A range of computer microscopes

Thursday, 6 November 2008

Hidden Doors

On the TV yesterday was the Home Show and they had a short clip where their expert walked through a wall that was disguised as a bookcase. This is of course something I've always wanted to have in my house since I was a small kid watching horror movies and Scooby Doo.

When I researched this more it turns out that Holly Black coauthor of the Spiderwick Chronicles has her own hidden door into a library.

I'm still trying to work out how this can be incorporated into my house although the smaller options of hiding boxes and cupboards could work? Perhaps I'll just have to plant a large bush in
front of the workshop and have a tardis shed as the entrance?

If you are interested in your own then there's a few people who can make them for you or you could try building one yourself?

Sunday, 2 November 2008

Engineer = Ingenious

On the train up to see the fireworks in Carlisle this year I heard a chap say to his friend, you know the word Engineer that means a man who's ingenious, it's Latin you know. I looked it up on Wikipedia and he was fairly close to the mark.

Latin ingenium (c. 1250), meaning “innate quality, especially mental power

Later this week I heard a couple of people use the phrase, "it's over engineered" in a derogatory way meaning overly complex, difficult to maintain or particularly convoluted (perhaps like a Heath Robinson invention or Rube Goldberg machine). However, I have to object to this definition, for me "over engineered" means that something was perhaps more sturdy than it needed to be or was capable at running at 110% without breaking. Looking at the Latin, it should mean even more than this, an over engineered machine should be one of higher quality or that has had more metal power applied to it. By this definition an over engineered solution should be easier to use, quicker to build, simple to maintain and last longer, when it's finally decommissioned I'd expect it to be fully recyclable. For me this is quality and hence this is over engineering.

Unfortunately the definition of words is set by the lowest common denominator and not by those of ingenuity....

Workshop Practice Series