Flap Discs (60 products)

Flap Discs

At Engweld, we stock a wide range of flap discs from leading brands such as Klingspor, as well as our own range of Engweld discs, which have been manufactured to the highest EU specifications and come with the OSA seal of approval.

Available in a range of sizes and grit types, you’ll be sure to find the ideal flap discs for your project with us.

What are flap discs used for?

Flap discs are incredibly versatile abrasive products, available in a vast array of different abrasive grains and grit sizes designed to cater for all customer requirements. They are the ideal choice for multiple stages and processes within metal fabrication, from stock removal to smoothing out surface imperfections and deburring.

KLINGSPOR SMT Flap Discs offer an aggressive cut while leaving a pleasing finish. Often, one of the SMT discs will take the place of what is now two separate grinding operations - heavy weld removal with a hard grinding disc and then final blending and clean-up with a fibre disc. A built-in fibre-reinforced consumable backing plate eliminates the need for a separate backing pad. Plus you may use your standard angle grinder mounting nut.

Engweld Silver Flap discs are made of alumina zirconia coated flaps, fastened equally to glass-fibre reinforced resin backing plates or glass fabric backing plates. For most metal grinding applications including working of welding seams, deburring, de-rusting and cleaning of castings. Available in Sizes 4-1/2" and Grits: 40, 60, 80.

Klingspor SMT 624 a new twist on convex flap discs. The new SMT 624 utilises a 12° angled backing plate. This will enable the disc to be used on more severely curved surfaces like pipes and storage tanks. Available in sizes 4- 1/2", 7" and Grits: 36, 40, 50, 60, 80, 120

Considering grit types: 

In the same way that sandpaper grains come in an array of sizes, which each grit size used for a certain application, flap disc grains work in the same way. At Engweld, our grit sizes range from 36 to 120, the larger the number, the finer the grain, and the smaller the number, the coarser the grain. 

Flap discs with coarse grains are generally used for the initial shaping and removal of stock, while finer grains are used for finishing and refinements. Below we have just put together a quick breakdown of what the grit numbers actually mean:

1. 36 - 40. Heavy-duty grit for heavy-duty applications such as removing large amounts of stock from workpieces. 
2. 36 - 60. Great for edge work, including edge bevelling and chamfering.
3. 40 - 60. Well suited for applications such as weld blending and grinding.
4. 60. The perfect size for deflashing and deburring.
5. 60 - 80. The best choice for finer work such as blending and the removal of rust.
6. 80 - 120. These fine grit discs are ideal for finishing, cleaning and refining. 

When to use coarse gritted flap discs:

For rapid stock removal and where the final surface finish does need to be highly refined or where the customer has no regard for the finish and just wants to get the job done fast. The coarser the grit, generally the quicker material removal rate (depending on the material) but the scratches left behind may be too deep to blend out at a later stage.

This is particularly apparent when comparing finishing processes on carbon steel and stainless steel. The temptation is to always opt for the coarser grains but this can hinder and prolong your finishing options at a later stage.

Coarse grits are also the best choice for soft such as soft steel and aluminium.

When to select fine gritted flap discs:

Fine grits should be used when a blended and more refined finish is essential to the project. They are typically used at the latter stages of the grinding process to clean up deeper scratches imparted by the coarse grain in stock removal.

Stainless steel for instance usually requires additional surface finishing processes because of the properties that each imparts on the material.

A highly refined finish is primarily used for decorative purposes example or the number 4 finish that is chosen for its anti-fingerprint, anti-bacterial properties in commercial handrails etc.

After initial stock removal from a coarser-grained flap disc or grinding wheel, the scratch would look unsightly on a stainless steel surface.

Finer grits are also more effective over smaller areas of contact and better suited to harder and more brittle materials.

FAQs

How to use a flap disc?

You can use a flap disc in the same way that you would use grinding wheels, with the main upside being that they have a much softer feel than grinding wheels do. And while the grind is much like hard grinding wheels, giving the operator greater control, and reducing the risk of removing too much stock or gouging the workpiece.

They are an ideal choice for a wide range of applications, as they allow the operator to save time, and cut costs, by performing both grinding and finishing in one efficient process.

What grit flap disc for mower blades?

One of the most common uses for flap discs is for sharpening the blades on lawnmowers, and having the ability to do this yourself is a great way to reduce your mower servicing costs! 

Grit size of between 60 and 80 is generally considered to be the sweet spot for sharpening lawn mower blades, aggressive enough to sharpen when needed, but also affording the operator enough control to ensure that not too much stock is removed.

Safety First

As you would when you are using any type of power tools, when you are using flap discs you should always operate with your safety in mind.

• Always inspect the disc before using it, if there are any signs of damage do not use it. Adopt the “better safe than sorry” attitude.
• When using any coated abrasive products, you should always use the guard on your grinder.
• You should always prevent and remove any build-up of the material you are working with from your flap disc. This is called preventing “load up.”
• Review all relevant safety materials and where possible get trained to use them.
• Never wear loose-fitting clothing or hanging jewellery, for obvious reasons!

To discuss your abrasive requirements, please contact Engweld using our contact form.