Description
The Dedra DED77671 render sponge pad is the polyurethane foam finishing disc in the DED7767 power float system — a 400 mm flexible foam disc designed specifically for floating and smoothing lime cement and gypsum plaster. Stocked in our power floats and sponges range, it is the pad to fit when the DED7767 moves from preparation work to the surface-finishing stage on internal plaster jobs.
Product Overview
The DED77671 uses a flexible polyurethane foam construction rather than the rigid plastic, polystyrene, or abrasive grid materials offered by the other DED7767 pads. That choice matters because flexible foam closes onto the surface under pressure and follows minor undulation, which is how the disc delivers a uniform float finish on lime cement and gypsum plaster without leaving the swirl marks a stiffer pad would mark. The PU material handles the moisture content of fresh and curing plaster without breaking down — open-cell foam in this density behaves quite differently from a hand-tile sponge.
At 400 mm diameter the disc matches the DED7767 host machine's pad mounting, attached via four Velcro straps onto the standard DED77670 mounting pad. The footprint covers a useful area per pass, which is what allows the machine to work an internal wall efficiently rather than just substituting for hand-floating in awkward spots.
Key Benefits
- Flexible polyurethane foam construction — closes onto the surface and follows minor undulation for an even float finish.
- 400 mm working diameter — covers internal wall area efficiently in continuous passes.
- Lime cement and gypsum plaster compatible — handles the moisture and chemistry of internal plaster systems.
- Velcro-mount system — four-strap attachment to the DED7767 host machine for fast pad changes.
- Smoothing and floating action — the finishing pad in the Dedra workflow, used after stripping or sanding stages.
Technical Specifications
| Property | Value |
|---|---|
| Diameter | 400 mm |
| Material | Flexible polyurethane foam |
| Mounting | Velcro (four-strap fitting) |
| Host machine | Dedra DED7767 power float |
| Mounting pad required | DED77670 |
| Primary use | Floating and smoothing lime cement and gypsum plaster |
Application & Compatibility
The pad works best on internal plaster finishing — lime cement and gypsum plaster systems where a mechanical float replaces or supplements traditional hand-floating. Use the disc once the plaster has reached its initial set but before full cure, when the surface is firm enough to take pressure but still workable enough for the foam to even out trowel marks and small undulations. The PU foam material handles the moisture content of curing plaster without saturating or breaking down through the working window.
The disc fits onto the DED7767 power float machine via the DED77670 mounting pad. For external thin-coat render finishing where a different surface texture is required, the DED77674 polystyrene pad is the alternative — polystyrene gives a different friction profile suited to silicone and acrylic finishes. The power floats for render finishing guide covers the full pad selection logic across the Dedra workflow.
Application Notes
Fit the pad to the DED77670 mounting pad with all four Velcro straps fully engaged before powering up — partial engagement risks the foam disc lifting under rotational load. For the cleanest float finish, work in overlapping circular passes at moderate pressure, letting the disc flex onto the surface rather than forcing it down. Excessive pressure compresses the foam against the wall and reduces the floating action that gives the pad its purpose.
Time the work to the plaster's set: too early and the foam picks up wet material; too late and the surface is too hard to respond to the floating action. The practical window varies with mix, ambient temperature, and substrate suction, so test in a small area before working a full wall. Clean the pad with water immediately after use — dried plaster bonded into the foam structure is much harder to remove than wet residue.
Trade Insight
The DED77671 earns its place on internal plaster finishing where hand-floating a full wall would otherwise be the time-bottleneck. The mechanical float covers area at a measurably faster rate than a hand-held trowel float, and the rotational action gives a more consistent surface across a continuous run than even an experienced hand can match. The complete Dedra pad sequence — DED77675 stripping pad for preparation, grid 16 and grid 24 sanding pads for surface refinement, then this PU foam pad for the float finish — covers the whole prep-to-finish workflow on one machine, which is the reason most plasterers running the system buy the full pad set rather than picking pads individually.
Is This Product Right for Your Project?
- Internal lime cement and gypsum plaster finishing: ideal — the PU foam is designed specifically for this stage of the work.
- External thin-coat silicone or acrylic render: consider the DED77674 polystyrene pad instead — different surface friction suits external render textures.
- Surface preparation and stripping: use the DED77675 stripping pad for the earlier stage of the workflow.
- Intermediate sanding and refinement: the grid 16 and grid 24 sanding pads sit between stripping and final floating.
Frequently Asked Questions
Which machine does this pad fit?
The Dedra DED7767 power float, attached via the DED77670 mounting pad. Both items are part of the same Dedra system — the mounting pad is the Velcro carrier between the machine head and the foam finishing disc.
How does the foam pad differ from the polystyrene pad?
The PU foam pad is built for floating and smoothing internal lime cement and gypsum plaster — flexible material that closes onto the surface for an even float finish. The polystyrene pad gives a different friction profile suited to external thin-coat silicone and acrylic render textures. They are sequential alternatives across different finish types rather than substitutes.
When in the plaster set should the pad be used?
After the initial set but before full cure — when the surface is firm enough to take pressure but still workable enough for the floating action to even out trowel marks. The exact window varies with mix, temperature, and substrate suction, so test in a small area before working the full wall.
How should the pad be cleaned after use?
With water, immediately after work finishes. Dried plaster bonded into the foam structure is significantly harder to remove than wet residue, and bonded material reduces the foam's flexibility on the next job. The render finishing guide covers pad maintenance across the Dedra range.