Which disc to use with an angle grinder
A complete grind to angle grinding:
Angle Grinding is an unavoidable part of tidying up welds and finishing metal work for painting or polishing. Whether cutting, grinding, sanding or polishing there are a vast array of “consumables’ that you can use. At The Weld Space we try and introduce people to a few different types which Richard Evans, founder of RichCraft Furniture as found helpful over the years when building bespoke furniture pieces.
Angle grinders are a versatile and essential tool in metalworking they rely on a range of consumables to achieve various tasks efficiently and safely. This tasks include aggressively removing excess material to removing mill scale from the material for weld preparation right through to sanding, polishing and buffing. An angle grinder is one of the most dangerous tools in the workshop so if you are going to use one please seek professional advice and at the very least wear all the appropriate Personal Protective Equipment.
For those not familiar with angle grinding; here is a essential list of Personal Protective Equipment (PPE) that is crucial when using angle grinders to ensure safety and minimize the risk of accidents:
Face Shield: Protect your eyes and face from flying debris, sparks, and particles.
Hearing Protection: Angle grinders can be very loud, This noise is not only unbarable! but can damage your hearing. Use earplugs or earmuffs.
Gloves: Protect your hands from hot material and sparks. They also help give you a good grip on the machine.
Aprons: Aprons help keep clothing back and sparks away from your body.
All our courses cover safe and proper use of an Angle Grinder and everyone gets instruction on how to use them safely and properly. In order to achieve a high quality finish to your work piece. Please check out our range of courses online. If you haven’t done so already.
TIG Welds unfinished Mild Steel
Grinding first phase.
Polished and Buffed.
Grinding and sanding discs come in various grits, catering to tasks ranging from coarse material removal to fine surface finishing. The choice of consumables is pivotal, ensuring that angle grinders remain adaptable and effective in the hands of the operator.
Realistically; you also need to keep into perspective cost. Buying and re-buying consumables add’s to a project and can get rather expensive. Using the right wheels at the right time will save you money. When buying angle grinding wheel make sure you buy the right size wheel for your angle grinder and it has the right bore. Most common angle grinders, the ones we use at The Weld Space, require a disc which is 115mm in diameter and have a half inch bore.
Angle Grinding Discs for Material Preparation for Welding
Preparing metal for welding is a crucial step in ensuring good quality of welded joints. It involves a series of steps aimed at removing mill scale and creating ideal conditions for the welding process.
First, the joins around the material to be welded need to be thoroughly cleaned to remove any mill scale. (Mill scale is considered an unwanted byproduct in the steel production process because it can negatively affect the quality of the finished steel product).
One of the best angle grinding discs we have found for material removal is these Non-Woven Preparation Wheels supplied by Screw-fix.
They have a number of pros and cons:
Pro:
Excellent removal of mill scale from steel
Reduces the amount of sparks during the process
Easy to use
Cons:
Don’t last very long
Expensive
Create lots of dust.
Example of Mill Scale Remove from Metal on our Introduction to Welding Course.
Angle Grinding discs for removing excess weld material
One of the most commonly used consumables is the abrasive grinding wheel, available for grinding Mild Steel and Stainless Steel. These grinding wheel are extremely hard and good at removing excess weld material from your work pieces. Alongside using used to prepare edges of material ready for welding.
They can be used to remove mill scale from a work piece but often leave deep scratch marks if not used carefully.
You can buy grinding wheels from most hardware stores but these Wheels from R-tech Welding last a long time and work very well.
Pros and Cons of using this Grinding Wheels:
Pro:
They are cheap to use
Last a long time.
Remove excess material nicely.
Con:
Create a lot of dust & Sparks
Can leave deeps cuts
Do not provide a smooth finish.
A more expensive option of removing excess weld material is to use a Flap Disc. Flap discs are constructed with abrasive materials such as aluminum oxide, silicon carbide, or zirconium, Which are bonded to a reinforced backing, making them sturdy and durable. They are softer than a grinding disc and more forgiving on the material forming to the profile of your work piece better.
They can use used for de-burring metal parts or for material preparation when using ERW Section of steel. They are available in a wide variety of grits with higher grit discs providing a finer finish. 40, 60, 80, 120 grits are available.
We have found zirconium or otherwise BLUE flap discs last longer and are more abrasives than Aluminum Oxide (Red) .
You can get these at any hardware store they are about £4-5 each.
Pros:
Great for removing welding material and finishing
Easy to buy
Provide a more smooth finish.
Cons:
Get expensive
Don’t last extremely long
Can clog with Mill Scale material
Flap Discs are a great abrasive wheel of choice for most metalwork applications. However if used excessive on a work piece they can create a dishy effect to the surface of the material.
Angle Grinding Discs for Sanding Metal
When you are trying to achieve a higher quality finish to your metalwork and you have ground down your excess material. The next stage is to sand the join this will smooth the gouges and grooves that where left by the grinding disc and flap disc.
Sanding Discs are a more specialist abrasive wheel and not widely available in hardware stores. You can purchase these in packs of 25 or 50 from a local Wellington Welding Store. Or online via Abtec4Abrasves an online supplier of abrasive products. Sanding Dsics are available in 40, 60,80 and 120 Grit.
To use a sanding disc you are required to fix a backing pad to the angle grinder. These are made of hard and soft material. The harder backing pads are more agressive but achieve a flatter surface finish. The softer backing pads are less agressive and more forgiving.
Backing Pads can be purchased online or via Screwfix here.
Pros:
Achieve a smoother material finish
Easy to use
Less sparks and dust
Cons:
Don’t last very long
Less abrasive
Additional equipment needed (Backing Pads)
Angle Grinding Discs for Finishing & Polishing Metal
When it comes to achieving the highest quality finish for your work piece or project. You need to move to more specialised finishing or polishing wheels. These help blend weld seams without removing material unnecessarily. These wheels can be used for preparing stainless steel for welding or Mild Steel TIG Weld seems but are not for removing mill scale as it will clog the wheel up very quickly.
These non-woven prep and finish wheels need to be used as a pack. You get 4 difference grades from Corse, Medium, Fine and Very Fine. They are perfect to use when finish a piece of metalwork to be powder coated. Sometimes referred to as Surface Conditioning Discs they use special material technology to blend welds and smooth the surface of metal for finishing. Essentially; these wheels buff and grind the material at the same time. The art to using these wheels is to left the wheel to the work. Do not put excessive pressure on the angle grinder.
Working through the grades will ultimately achieve the highest quality finish although they can be used individually for example. Just using the Meidum Disc.
You can purchase individually from Wellington Welding Supply Store or Online.,
Pro:
Achieve amazing finishing on metal for painting / powder coating
Helps polish metal
Little Dust and Sparks
Less noise
Cons:
Very expensive to use (£8 each)
Don’t last very long
Time consuming to use
Angle Grinding Discs for Cutting Metal
Cutting discs for angle grinders, also known as cut-off wheels or cutting wheels, are a useful disc for metalworking, and fabrication.
These discs are specifically designed to efficiently cut through a wide range of materials such as Mild steel and Stainless steel. They are composed of abrasive materials like aluminum oxide, silicon carbide, or zirconia alumina, which are bonded together to form a thin, reinforced wheel.
Cutting discs come in various diameters and thicknesses,(1mm through to 5mm) each optimised for specific cutting tasks. The Thinner discs are faster to cut through material with the thicker discs being slower but more accruite.
Being a hand handle cutting tool Cutting discs are no very accurate at cutting straight and square lines. They are a useful back up option if a saw is not available. Or help when cutting odd angles or strange shapes.
Cutting lists are normally available in packs of 10 from any hardware store.
Pros:
Simple to cut metal.
Fast
Con:
Not accurate
Create A LOT of sparks and dust
Dangerous! Excessive pressure can cause the disc to break!
The information contained within this post is meant to act as a guide to helping DIY metalworkers achieve amazing finishes to there projects and metalwork. However, it doesn’t replace the chance to trail different consumable grinding wheels or proper tuition gained from experience fabricating many weird and wonderful piece of furniture.
All our courses cover Angle Grinding and metal finishing allowing customers to explore and try the different consumables discussed.
Check out our COURSE PAGE and book on a course to learn more.
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