Buying a MIG Welder – Continued

The quality of a MIG Welder varies tremendously, dependant upon country of origin. Some welders made in eastern Europe / Taiwan / China tend to be of a lower price and accordingly of lower quality, they tend to have cheaper electronic components, don’t always last as long and spares are often difficult to get hold of.

A welder that has a higher initial cost may save you money long term as usually electronic components and wire feed and drive units are of superior quality. So its definitely worth putting in a bit of leg work before buying.

A point worth noting is that searching for a local welding supplier may be worth it as they will advise you of what spares they carry or have access to should your welder go wrong, they will more than likely be able to advise you on a purchase.

A DIY MIG Welder that is occasional use only may cost you in the region of £200 to £350 dependant on make or model. You may also consider searching on-line or in local adds (Gumtree for example) for a good used MIG welder. A used welder that has been appropriately maintained and cared for might be more than sufficient in meeting your needs and come at a price you can afford. However, beware as a good second hand MIG welder will command good residual value even more so if it is a single phase 240v 3 pin plug supply that will run from a 13 amp household socket.

Features to look for in a MIG Welder may be :- ease of use, large or small torch, “euro” torch connector, size of filler wire reel, portability (is the welder on castors or light enough to lift and move around). Does the welder have a series of rocker switches, giving combinations of output amps, or does it have a dial to increase output amps (which is infinitely more adjustable than rocker switches). All of which may make for easier use.

The material thickness will determine the amps needed for the MIG welder you are considering.

The following shows maximum steel thickness for a butt weld based on amps (approx):

  • 90 amp, 2.0 mm
  • 110 amp, 2.5 mm
  • 130 amp, 3.0 mm
  • 150 amp, 4.0 mm
  • 180 amp, 5.0 mm

Keys to Using a MIG Welder

A MIG welder works through the creation of an arc between the parent metal being welded and the wire electrode. The arc creates the weld which is sealed and protected from elements by shielding gas being fed to the arc. A MIG weld generates a lot of heat and light and the welder must wear a protective shield to protect his or her eyes from ultra violet rays.

The Difference between TIG and MIG Welding

TIG welding uses a tungsten electrode. The electrode does not burn off or melt during the welding process. MIG welding uses a wire, which melts off into the weld pool. MIG welding was developed in the 1940s as a way to bind aluminum and nonferrous metals while TIG welding has been developed as a more specialist form of stainless welding steel, aluminum, copper and magnesium alloys.

Safety

One of the basics related to MIG welding is the observation of safety procedures. MIG welding uses a torch assembly that holds a consumable wire electrode that creates the weld. The welder must maintain a short arc in order for the weld to be effective. Wearing a safety shield and ear plugs and not wearing loose, combustible clothing are essential to a safe working environment when using a MIG welder.

Competency in MIG Welding comes when the operator can “set up” the machine for a particular welded joint.

Set up meaning that he or she can set the variable parameters of the welding machine (wire feed speed, amperage, gas flow) and handle the torch assembly accurately to maintain an even fillet of weld, which has sufficient penetration into the parent metal to melt and mix the molten parent and filler material into one,creating a good strong weld, and also have the skill and knowledge to maintain correct torch angles, distances from the welded joint and speed at which the operator moves the torch along the welded joint.

A MIG welder can be very useful for some car projects.

  • Floor panels.  Floor repairs are common particularly on older cars where the effects of water ingress into welded joints rapidly combines with road salt and damp atmosphere to speed up oxidation (better known as corrosion or rust).
  • Tube frames. Roll cages for racing, space frame chassis and chassis rail repairs.
  • Exhaust repair. Ideally suited to MIG welding, why replace an exhaust silencer box when you can MIG weld a “patch” on it stop gases leaking out
  • Bodywork. Welds on the bodywork can be very difficult for a novice MIG welder to produce successfully. This is mainly down to lack of skill in controlling heat input and distortion, although as your skill level increases this will be possible.

Thanks for reading our blog – we hope this has been of use to you.

Recommended sites

FLASH CUSTOMS – Specialist Custom Car & Motorcycle Parts
Loaded Wallet – Discount and cash back offers
Cash Back – Cash Back & Money Saving offers

What to look for when buying a MIG Welder

At some point or other those of us that “tinker” and modify cars or motorcycles, off road vehicles, race and track day cars and motorcycles will need to “weld” something, even if its only a simple bracket, or repair patch on a sill or chassis.

There is no getting around it that having the skill and equipment to weld small parts would be very useful in this instance.

A MIG welder is typically used in the automobile repair & fabrication industry. The process of MIG or metal inert gas welding involves a consumable wire electrode (fed through a torch assembly) & a supply of shielding gas (again fed through a torch assembly)to protect the weld. This differs from TIG welding, which makes use of a fixed, non-consumable tungsten electrode that produces a high energy arc. The method is rarely used outside, due to the effect of breeze blowing away the shielding gas, but is common inside a workshop or automotive repair facility.

Here is my beginners guide to selecting the right MIG welder for your needs.

  1. There’s lots of things to think about, electrical supply, space, where you will be welding, what you will be welding, budget and lots of more
  2. Another thought is that anyone with no experience in MIG welding really ought to seek professional advice and at least do a bit of research on MIG welding before jumping in with both feet. Please don’t just go out and buy the first MIG plant that you see.
  3. Take some time and consider what it is you want to be welding, will you be wanting to weld for example a modern-ish car (monocoque  chassis) or a vehicle such as an off roader with a  separate chassis. For a modern car with relatively thin body panels a Mig welder of approx 100amps range may suffice. For heavier chassis repair work a Mig welder with a 150amps range or more may be required. Certainly if you are going to be welding gates, railings, or any such thicker material a MIG welder with an output of 180 / 200 amp output may be required.
  4. So think about what use you will be needing the welding plant for, not just your budget, it would be false economy just to opt for the cheapest brand / welder and expect it to work miracles and weld everything in the world.
  5. Most “DIY” MIG welders will be supplied from a 240volt, 13 amp household socket. This tends to be the case up to approx 180 / 200amps, dependant on welder, make, model, specification etc. Any higher (or in some instances less) and you may need to look at installing a 16 amp or even 32 amp rated socket.

  • Over the years I have owned at various points several MIG welders from DIY to 3 phase industrial welders, I started off with a little Sealey mini MIG 100 amp set, this worked fine for basic bodywork, sill repairs, valance repairs, and single skin welding, and although in those early days there were not “gas less” MIG sets on the market I used to run this set with shielding gas – from a pub bottle. This was co2 – carbon dioxide used in the pub trade. Although a most basic set with only 4 settings it worked well once set up correctly.
  • Once I got into some other modifications and repair work I brought a Clarke 180amp “turbo” (fan cooling) single phase MIG set, again running on co2 pub gas, this worked great on heavier thickness’s, 3 & 4mm chassis plates, land rover repairs and welding new floor pans in VW beetles. Again this only had 4 heat or “output” settings with adjustable wire feed.
  • Although many people say that they can weld, the real difficulty with MIG welding is that it can look a “nice” clean, even fillet and yet still be a very poor, “weak” weld due to lack of penetration into the parent metal. In effect the weld “bead” sits on the top of the material being welded. This can be caused through lack of heat input, incorrect torch angle, weld contaminants (paint, grease, under seal, corrosion etc), lack of operator skill. This is particularly important when welding critical parts / support structures. I always say “set” the welding plant parameters up using a piece of off cut or scrap material to ensure your weld is good and strong, before continuing to weld your actual job.
  • Further to this “professional” MIG welders that I have used over the years up to 3 phase supply (3x 240v supply), 400 amps a “Fronius” electronic, programmable machine with LED touch screen controls and very technical parameter set up and control was by far the best (also by far the most expensive).

Considerations of cost and quality of machine, reliability and access to spares is another important factor in making a purchase. We all look at the dreaded eBay for prices and varying types of the product we are looking at buying. I would advise that anyone buying a MIG welding plant complete some research first and  DO NOT in any circumstances buy the cheapest machine you can see on-line.

THINK ABOUT – What you need the welder for, is it a common make or brand, can you find feedback or reviews about the machine you are interested in, can you get spares for it (we will discuss this later), will the machine rating be adequate for your welding – e.g. if you are welding patch repairs in cars will the machine weld for more than 10 minutes or so without overheating and cutting out?
This is what we call “duty cycle time” for example the manufacturer may state “duty cycle 10% at 75% max amperage. Therefore if your welders maximum amperage is 100 you can weld at 75amps for 10% of any time period (e.g. 6mins in any 1hr). This may be absolutely fine if you are completing spot welds, short stitch welds or small welds in between “setting up”. This is typical of cheap MIG welding machines for DIY use.

You may need to check that your power supply where you wish to weld is adequate – be careful to check specification of welding machine before purchase as I have seen some put the supply rating (e.g. 16amps) at the bottom of the spec listing. This means that the machine will not successfully run from a standard 3 pin 240v 13amp household socket.

Buy a machine with good ratings and feedback , if unsure speak to your local welding supplier (search yell.com), dont be frightened to ask for advice – you may not buy a machine from them but if they are business “savvy” they will do what they can as if they are helpful you may well go back to them for spares.

On the subject of spares – typical spares you may need are:- Contact Tips, filler wire reels, gas shrouds (sometimes called nozzle), in some cases disposable gas bottles (for shielding gas), if your machine breaks down:- common items needed may be gas valve, contactor, switches, torch assembly, torch lead, torch lead liner.

Finally, make sure you buy a welding plant from a reputable dealer with a warranty.

If you require any help and advice in welding related issues please  email us directly at sales@flashcustoms.co.uk

We are specialist custom parts manufacturers, Welding, Machining and Fabrication are our forte

Thanks for reading our blog – we hope this has been of use to you.

Recommended sites

FLASH CUSTOMS – Specialist Custom Car & Motorcycle Parts
Automotive LED Lights – Car & Motorcycle LED Lighting Solutions
Loaded Wallet – Discount and cash back offers
Cash Back – Cash Back & Money Saving offers

How an Internal Combustion Engine Works

Many articles have been written debating the design, manufacture, improving the Internal Combustion Engine but, how many people really understand how an engine works?

I have found an excellent Haynes model that you build from a kit that will help any budding motor engineer improve their basic knowledge of an Internal Combustion Engine.

This could be ideal for any apprentice, motor vehicle student, motor sport student or young motor enthusiast, also great as a gift or present.

 Haynes Internal Combustion Engine Model

The engine you build is a greatly simplified version of a real car engine. The model is designed to be fun to put together, and to make it easier for you to understand how a full-size four-stroke car engine works. This box contains all the parts and tools you need to assemble the working model. It comes complete with its very own Haynes Manual giving you clear step-by-step instructions to guide you through the build process, all you need to provide is the time, two batteries and a little vegetable oil. The on/off controller also includes a sound chip which reproduces the noise of an engine starting, as the model begins to work. Cracking little working model.

WATCH VIDEO

Thanks for reading :)

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Why is it important to use Antifreeze in your Car Cooling System

Use Antifreeze in your cooling system summer and winter ! – Why you might ask?

One main point to remember when considering your vehicle cooling system is that modern engines use a range of materials now. Some of which are more susceptible to corrosion than others. Corrosion is a common denominator in reducing cooling system efficiency by means of cooling fluid contamination and blocking the inner bores of cooling pipe work and water jackets, hence reducing efficiency.

Making sure that you’ve got the correct anti-freeze in the right concentration is critical to the health of your engine.

Cooling capacities of modern vehicles are generally smaller, operate at higher temperatures and pressures and therefore require more maintenance to ensure efficiency is maintained.

Approximately 60% of engine failures can be attributed to cooling system problems.

As a rule of thumb, only about 28% of the thermal energy released by burning fuel in the engine is available for driving the car.

  • About 7% is used to overcome friction in the engine, drive train, tyres etc.
  • Another 35% disappears out of the exhaust, and
  • The remaining 30% has to be removed by the coolant or the engine block, otherwise internal components would start to suffer overheating, rapid wear and fatigue, leading to failure.
If you are unfamiliar in the operation of automotive cooling systems this cheap book below is an ideal starting point.

Antifreeze is multi-functional and vital to the correct operation of the engine. A modern coolant/antifreeze needs the following features:

  • Corrosion prevention
  • Excellent heat transfer
  • Protection from freezing
  • Prevention of scale build up
  • Compatibility with hard water
  • Stability at high temperature
  • Compatibility with plastics and elastomers used in the engine
  • Low foaming

So as you can see with so many functions to perform it is very important to the maintenance and health of your engine to regularly check the ratio of water to antifreeze in your system

Bluecol – Recommended Antifreeze 5L

Every couple of years it is also a good idea to flush through the coolant system, this is especially important if you buy a second hand car and have no idea when the coolant was changed last

 Wynns 56064 325ml Radiator Flush – Recommended Coolant System Flush

Its also important to remember that any antifreeze added to your system should be to the specification stated by the vehicle manufacturer.

Ethylene glycol is a product of the petro-chemical industry and is used as the basis of antifreeze, this has the added advantage of raising the boiling point of the cooling mixture. More recently propylene glycol has been introduced as a less hazardous alternative to ethylene glycol.

The important recent technical advances have been in the field of corrosion prevention, hard water compatibility and control of scale build up.

Engine design has changed to improve fuel efficiency and lower emissions as well as reducing weight and costs. These demands have made engine operating conditions even more severe, so that much more is required from the cooling system.

Leak free coolant systems are a must as almost all modern cooling systems run under pressure, once this pressure is reduced the coolant may boil at a lower temperature.

On this note any system that has developed any leaks must be rectified as soon as possible.

 K-Seal recommended permanent coolant system leak repair.

It is generally recommended that a mixture of  between 40 & 50% Antifreeze to water is used for summer coolant and winter freezing prevention. Coolant systems are “sealed” generally and should not need topping up, however if water levels in the coolant tank are noticed to be reducing then it is important to inspect the system for leaks. Also important to check is if the coolant mixture is cloudy or “sludgy” as this may also indicate issues of combustion gases / oil getting into the cooling system via a cracked block or head or head gasket leaking problems. Get it checked out asap.

National standard for antifreeze are – BS6580:2010 or ASTM D 3306 and such fluids should provide a basic level of performance for cars and light vans.

New developments in cooling technology has led to the introduction of Organic Acid Technology (OAT). Corrosion inhibitors in OAT products last much longer in use than those in traditional antifreeze and that is why many service specifications only require coolant fluid changes are completed every 5 years now.

On a final note, water quality in certain areas vary tremendously still. There are areas that are known as being “hard water” areas and this can affect the performance of your vehicles coolant system – think about the furring of your kettle element or washing machine elements.

To finish; a few points to look out for concerning your cooling system.

All above pictures point to poor coolant system operation and in some instances major engine faults.

  1. See the thermostat – top left covered in corrosion deposits that could render it inoperable.
  2. Top right small corrosion showing on radiator – this may only be a small “pin” hole in the radiator and not noticeable or indeed affect the operation of the system until it is up to working temperature.
  3. Third image – the thermostat housing sludged up with “gunk” reducing the bore size for cooling fluid to flow through.
  4. The last one at the bottom – radiator header tank overflowing with brown sludge – a sure indication that oil or combustion vapours are entering the coolant system.

Dont forget – here at FLASH CUSTOMS – we can custom make alloy water pipes, alloy radiators and supply silicon hose kits and parts to make up smooth bore, high flow cooling systems, for fast street and race use.


Hope this blog has been of some use to you, thanks for reading :)

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What is a Water Swirl Pot used for?

High performance Race, Drag or Modified Street Cars may benefit from a Water Swirl Pot in the water system. Running a coolant system under pressure and close to the limit may lead to “hot spots” in the water system causing localised “boiling” of the water causing steam and air to develop within the cooling system.

Shown above a typical example of a water swirl pot. If designed and integrated correctly into the system the “pot” will cause the water to “swirl” and spin within the pot. This will allow any potential air or steam in the system to rise to the top and vent back to the header tank (if separate) or in this case rise to the top of the tank away from water flow. Bear in mind in this instance the swirl pot will also aid in dissipating heat away from the water during the “swirl” assisting in reducing water temperatures. Note then it is also important to position the swirl pot in the coolest place possible within the engine bay. Typically it will need mounting between the thermostat (if fitted, or engine water outlet) and the radiator intake to maximise efficiency. If the swirl pot is not integrated as part of the header tank then an air outlet should be welded in the tank at the top and vented back to the main header tank. Intake and outlet (flow pipes) should be large enough to suit the engine water flow and not impede it in any way. The “taller” the swirl pot the more cooling effect and chance for the air to percolate to the top of the tank out of water flow. Remember hot water rises and cold water descends so as the water swirls and cools it naturally flows to the bottom of the tank – similar to your kettle or teapot at home.

Which is why your cup of tea can be warm at the top of the cup and cool at the bottom. Any air in the water system will reduce the amount of heat being transferred as it flows through the fins within the radiator & hence the importance of removing or venting the air back to the header tank or out of the water flow

Thanks for reading :)

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