Description
Gradation 24 is the middle abrasive grade for the Dedra DED7767 render float: a 370 mm silicon carbide face that Dedra lists for stripping old paint, cleaning off adhesive and plaster residue, and lapping polystyrene during insulation work. One disc, several preparation jobs, no tool change.
Where to Use the DED7767G24 Gradation 24 Disc
The grid 24 sanding pad for render float preparation carries a 370 mm abrasive face of silicon carbide, which Dedra specifies for removing old paint coatings and adhesives and for lapping polystyrene foam. It is stocked by Renders World in the power float machines, pads and sponges collection as one of two abrasive grades for the same machine.
That single line from the manufacturer's catalogue covers four distinct site jobs, which is what makes the disc worth keeping on the van rather than ordering per project. The consequence for planning is simple: the preparation stage needs one consumable, not four.
- Old paint coatings: weathered or flaking films taken back to a sound substrate before priming.
- Adhesive and plaster residue: squeeze-out and dried mortar removed from masonry and board faces.
- Surface levelling: proud areas and stepped substrate brought back before a basecoat goes on.
- Lapping polystyrene: board faces and joints worked flat during insulation work, in Dedra's own wording.
Why Operators Order the Gradation 24 Disc
The buying case rests on what the manufacturer actually publishes, and on two divergences this audit found between Dedra's documents. Both are worth knowing before an order goes in, because each one changes what you check on the delivery note.
- Silicon carbide abrasive: named as the abrasive on the DED7767G24 catalogue entry, so the disc cuts masonry, paint film and thermoplastic board without a grade change.
- Order on the 370 mm line, not the 390 mm one: the same catalogue entry shows 390 mm under a generic diameter field and 370 mm under disc diameter, and the DED7767 manual gives 390 mm as the machine's own disc diameter. The 370 mm figure is the abrasive face — quote it when you compare suppliers.
- Not in the manual's accessory list: the DED7767 manual lists only DED77671, DED77674 and DED77675 as accessories for sale, while Dedra's current catalogue lists this disc as designed for the DED7767. Check the catalogue, not the manual, for what fits.
- Priced as a single consumable: £10.90 per disc as displayed in August 2026, at a variant weight of 200 g, so a stock of spares adds little to a delivery.
DED7767G24 Specification as Dedra Publishes It
| Property | Value | Where it comes from |
|---|---|---|
| Gradation | 24 | DED7767G24 catalogue entry |
| Disc diameter | 370 mm | DED7767G24 catalogue entry |
| Abrasive | Silicon carbide | DED7767G24 catalogue entry |
| Stated application | Removal of old paint coatings and adhesives, lapping polystyrene foam | DED7767G24 catalogue entry |
| Producer code | 5902628776853 | Catalogue entry and store record, in agreement |
| Mounting | Hook-and-loop, onto the machine's mounting disc | DED7767 manual, section 6 |
| Machine it is listed for | Dedra DED7767, 710 W, 110 min⁻¹ | DED7767 manual, technical data |
The machine figures above are properties of the Dedra DED7767 render float rather than of the disc, and its product page owns them in full. Two are worth carrying here because they govern how the abrasive behaves: the machine is rated S2 15 minutes, a short-duty rating, and it turns at 110 min⁻¹, which is slow enough that cutting comes from grade and contact rather than from speed.
How to Fit and Use the Disc on the DED7767
Fitting to the mounting disc
The manual sets the assembly order before any work starts, with the machine disconnected from the supply. Ordering a grid 24 sanding pad for render float work assumes that mounting disc is already fitted and sound, so check it at the same time as the abrasive.
- Disconnect the machine from the mains before any preparation, as the manual requires.
- Fit the mounting disc to the spindle, matching the bore to the shaft, and tighten it with its screw.
- Press the abrasive disc onto the hook-and-loop face of the mounting disc.
- Start the machine horizontally and off the wall, and let it reach full speed before touching the surface.
Running it on the wall
The manual's own technique note is to guide the machine in semicircular movements and to match the pressure to the work in hand, checking the surface as you go until the finish you want appears. That is the whole of the documented method, and it holds for every grade of disc on the platform.
Renders World finds the pressure point is where most operators lose time: the abrasive cuts best held flat, and tipping onto an edge concentrates the work into a narrow arc. Keeping the disc flat is the step worth getting right, because a flat face leaves a platform that takes a basecoat cleanly. Where the prepared wall runs straight into the reinforcing layer, the EPS adhesives basecoats range covers the next material stage, and preparing substrates before rendering sets out what a sound surface looks like before any of it goes on.
Maintenance — Knowing When the Abrasive Is Spent
Dedra ties disc condition directly to output. The manual instructs a check of the abrasive disc for wear before every start, and its fault table gives a worn abrasive disc as the cause of low sanding efficiency, with replacement as the remedy — so a drop in cutting speed is a diagnosis, not a nuisance.
- Check before each start: a spent face costs more in passes than a new disc costs to buy.
- Treat slow cutting as the signal: the manual names it as the symptom of a worn disc.
- Keep the machine clean: the manual singles out the motor air intakes, best cleared with compressed air.
- Store flat and dry: protects both the abrasive and the hook-and-loop backing between sessions.
Two further pads exist for this machine whose catalogue codes and published titles disagree over which is which. Renders World is holding both descriptions until the manufacturer confirms them, so neither is described by function here; order those by code and confirm the contents on arrival.
Gradation 16 or Gradation 24 — Choosing the Grade
| Disc | Documented gradation and face | Application Dedra states |
|---|---|---|
| DED7767G24 (this disc) | Gradation 24 · 370 mm · silicon carbide | Old paint coatings, adhesives, lapping polystyrene |
| Gradation 16 disc | Gradation 16 · 370 mm | Old paint coatings, adhesives, lapping polystyrene |
The two entries carry the same stated application word for word, and the same face diameter. On Dedra's own documents the grade number is therefore the only published difference between them, and the ordinary abrasive convention — a lower number is the coarser grit — is what tells you which cuts harder. Anything beyond that, including a fixed first-pass and second-pass sequence, is site practice rather than a manufacturer instruction, and the guide to power float techniques and tool selection is where that sequence belongs.
Is the DED7767G24 Right for Your Machine and Job?
- You run a Dedra DED7767: a direct fit — the disc is listed for this machine and presses onto its hook-and-loop mounting disc.
- Paint, adhesive residue or levelling work: all three sit inside the application Dedra states for this gradation.
- Polystyrene board faces: lapping polystyrene during insulation work is named on the catalogue entry for both grades.
- A heavier cut than gradation 24 gives: the coarser gradation 16 disc is the sibling to compare, on the same 370 mm face.
- Any other power float: confirm the model first, since Dedra publishes this disc against the DED7767 only.
Where the prepared elevation is heading for a thin-coat finish, the Renders World silicone render range is the next stage after priming, and the DED7767 power float page carries the full machine specification if you are buying the platform alongside the consumable.
FAQ — Fitment, Gradation, Maintenance and Limits
Which machine does this disc fit?
Dedra publishes the DED7767G24 as designed for the DED7767 render float, and the manual describes working discs attaching to that machine's mounting disc by hook-and-loop. No other machine is named in either document, so confirm the model before ordering.
What is the documented difference between gradation 16 and gradation 24?
The grade number, and nothing else that Dedra publishes. Both discs are listed at 370 mm with identical stated applications, so a grid 24 sanding pad for render float work differs from the 16 only in how coarsely it cuts.
How do I know when to replace the disc?
Check the abrasive before each start, as the manual instructs, and treat a fall in cutting speed as the indicator — Dedra's fault table gives a worn abrasive disc as the cause of low sanding efficiency and replacement as the fix.
Are there limits on how long the machine can run?
Yes. The manual rates the DED7767 at S2 15 minutes and instructs that it reach full speed before contacting the wall, so preparation is planned in working spells rather than continuous runs.
How many discs should I order for a job?
No document states a service life or an area per disc, so no figure is published here. Ordering spares alongside the first disc is the practical route, at £10.90 each and 200 g apiece.
Technical Documentation
- Dedra DED7767 instruction manual (PDF) — technical data, assembly, operation, maintenance and accessory list.
- Dedra DED7767G24 catalogue entry — gradation, disc diameter, abrasive and stated application.
- Dedra DED7767G16 catalogue entry — the sibling grade, source for the comparison table above.