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Duckman
15-11--2006, 12:06 AM
There are two types of welding and welding aka stick welding and MIG welding.The former is really good on steel at least 3mm thick and can be done outside on a windy day with no problems as long as there is no dry combustable material around. I have arc welded on 1mm black sheet steel with some practice but it is not so easy.

MIG welding excels on thin gal sheet steel and car bodies. If there are gusts of wind it will interfere with the shielding gas. There is gasless MIG wire available but is difficult to use. So far I have not bought a MIG welder because of the prohibitive cost of just hiring the shielding gas bottles. A different situation in the UK I think.

Anyway it is probably better of to start with an arc welder. Essentially on a skill level it is similar to painting; there is not much to it but to do a first class job requires practice.

In the course of arc welding, a certain amount of ozone is produced. It has a strong musty smell and is a noxious gas. Clamps are most useful when welding. If there is as little as a 1mm gap between pieces you will only end up burning a hole, therefore pieces to be welded must be clamped tight.
It is essential to wear a face mask to avoid eye damage. Clamp on the earth lead to the work piece a switch on the welding unit. For small piece of work, set the amperage at about 80 amps. If it only has two setting use the lower one. Start by striking the end of the rod ( I generally use 2.5mm rods)against the work piece like you strike a match. Move the rod along the join pushing it in to the bottom of the join at the rate of about 1mm per second. If it sticks it mean the amperage is not high enough or you are moving along too quickly. If there is excessive spluttering then the amperage is too high. When finished leave for couple of minutes and chip off the slag. It will be quite obvious if it is a good joint. When the piece is completely welded all round and painting is required, it is better apply red primer while still warm.

joss
27-12--2006, 01:09 AM
what about gas welding?
Mig is easyer to learn and gives a better finnish then stick as well

Badger
27-12--2006, 09:15 AM
Ducky, ;) ever heared of T.I.G. welding? :)

Duckman
27-12--2006, 09:31 AM
Both these types are more expensive.