Description
The DED77671 polyurethane foam pad is the 400 mm finishing disc in the Dedra DED7767 system, designed for floating lime cement and gypsum plaster after the surface has reached its initial set — covering internal plaster finishing on walls and ceilings where hand-floating would otherwise be the time bottleneck.
Where DED77671 Fits in the Internal Plaster Workflow
For internal plaster finishing on lime cement and gypsum substrates, the Dedra DED77671 polyurethane foam pad delivers a mechanical float finish across continuous wall and ceiling runs once the plaster has reached its initial set. It is stocked at Renders World in the power floats and sponges range as the finishing pad in the seven-pad DED7767 ecosystem. The 400 mm working diameter covers area per pass that hand methods cannot match, which is why renderers running the host machine adopt this specific disc once the prep and sanding stages are complete.
The choice of flexible PU foam over rigid plastic or abrasive grid material matters here. Foam closes onto the surface under moderate pressure and follows minor undulation, evening out trowel marks and small surface variation that a stiffer disc would either skim past or chatter against. The result is the kind of uniform float finish across a full wall that takes an experienced hand-floater significantly longer to achieve.
Why This PU Foam Pad Saves Time on Site
- Flexible PU foam closes onto the surface — follows minor undulation for an even float finish, where rigid pads skip across low spots.
- 400 mm working diameter — covers internal wall area efficiently in overlapping circular passes.
- Plaster-chemistry stable — open-cell PU handles moisture content of curing lime cement and gypsum without breaking down through the working window.
- Velcro four-strap mounting — swaps onto the DED77670 mounting pad in under thirty seconds, so workflow transitions between sanding and floating stages are quick.
- Internal plaster specific — purpose-built for the finishing stage rather than a general-purpose accessory pressed into service.
Technical Specifications — DED77671 Pad Data Sheet
| Property | Value |
|---|---|
| Disc diameter | 400 mm |
| Material | Flexible polyurethane foam (open cell) |
| Mounting | Velcro, four-strap fitting |
| Host machine | Dedra DED7767 power float |
| Mounting pad required | DED77670 (Velcro carrier disc) |
| Primary use | Floating and smoothing internal lime cement and gypsum plaster |
| Workflow stage | Finishing (post-stripping, post-sanding) |
| Country of dispatch | UK stock |
The pad is a system component rather than a standalone tool. It does not function without the DED7767 host machine and the DED77670 mounting pad, which together form the rotational drive and Velcro carrier the foam disc attaches to.
How to Use DED77671 Effectively on Internal Plaster
Fit the foam disc to the DED77670 mounting pad with all four Velcro straps fully engaged before powering up the machine. Partial engagement allows the disc to lift under rotational load, which marks the surface and risks the pad detaching mid-pass. Confirm the head is square to the wall before contact, then power up clear of the substrate and bring the running disc onto the surface — starting under load draws excessive current through the machine's carbon brushes and shortens their service life.
Work in overlapping circular passes at moderate pressure. The foam needs to flex onto the surface to do its job; excessive pressure compresses the disc against the wall and reduces the floating action entirely. Let the disc cut at its own rate. On substrates where silicone render will follow, the internal plaster pass with this pad sets the smoothness baseline the render will telegraph through if the float is uneven.
Time the work to the plaster's set. Too early and the foam picks up wet material that bonds into the open-cell structure. Too late and the surface is too hard to respond to the floating action at all. The practical window varies with mix, ambient temperature, and substrate suction, so test in a small area before working a full wall. The power floats for render finishing guide from Renders World walks through the timing logic across different plaster types.
How DED77671 Sits in the Full DED7767 Pad Sequence
The pad family for the DED7767 host machine runs across the prep-to-finish workflow, and each disc has a specific stage. Renders World stocks the full pad family from UK warehousing so installers can build the kit by stage rather than committing to the whole set on day one.
- Surface preparation: the DED77675 steel-blade stripping pad removes paint, wallpaper, plaster nibs, and bonded coatings.
- Coarse refinement: the grid 16 sanding pad takes down stripped or rough surfaces in the first sanding pass.
- Fine refinement: the grid 24 sanding pad follows grid 16 and leaves a surface ready for floating or priming.
- Internal floating (this pad): the DED77671 PU foam disc floats lime cement and gypsum to a closed, even finish.
- External render finishing: the DED77674 polystyrene pad opens up the texture on thin-coat silicone and acrylic render outside.
How Pros Get the Best Result From This Pad
The two habits that distinguish a clean foam-floated surface from a chattered one are pressure control and timing. Renderers used to hand-floating tend to push harder than the foam needs, compressing the disc and losing the flexibility that makes it work. Light, sustained pressure with the machine doing the rotational work delivers a markedly more uniform finish than pressing the head into the wall.
Timing of the float pass is the second variable, and it is the harder one to teach. Lime cement and gypsum behave differently as they approach the floating window, and the same room can have walls drying at different rates depending on sun exposure and ventilation. Working a small test area first — typically a corner section of around half a square metre — confirms the plaster is ready before committing to a full continuous run across the room.
Clean the pad with water immediately after use. Dried plaster bonded into the open-cell foam structure is significantly harder to remove than wet residue, and bonded material reduces flexibility on the next job, which in turn reduces the floating quality the pad was bought for. A two-minute rinse at the end of each shift extends the pad's working life considerably.
Is DED77671 Right for Your Project?
- Internal lime cement and gypsum plaster finishing: ideal — the PU foam is purpose-built for this stage of the work and outperforms hand-floating across continuous wall area.
- External thin-coat silicone or acrylic render: consider the polystyrene pad instead — the different friction profile suits external render textures and finishes them appropriately.
- Surface preparation or coarse sanding: earlier-stage pads in the same Dedra workflow handle stripping and grit refinement.
- Hand-only sites without the DED7767: the pad is a system component and does not function without the host machine and mounting disc.
FAQ — DED77671 Use, Compatibility, Maintenance
Which machine does the DED77671 fit?
The Dedra DED7767 power float, attached via the DED77670 mounting pad. Both items are part of the same system — the mounting pad is the Velcro carrier between the machine head and this foam finishing disc. The foam pad cannot be used directly on the machine head without the mounting pad in place.
How does the PU foam pad differ from the polystyrene pad?
The PU foam disc 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 disc gives a different friction profile suited to external thin-coat silicone and acrylic render textures. They are sequential alternatives across different finish types, not substitutes for the same job.
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, ambient temperature, and substrate suction, so test in a small area before working the full wall. Working too early loads the foam with wet plaster; too late and the surface no longer responds to the floating action.
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 flexibility on the next job. A two-minute rinse at the end of each shift extends working life considerably and keeps the float quality consistent across multiple jobs.
How much surface can the pad cover before it needs replacing?
Pad service life depends heavily on pressure habit, cleaning discipline, and the abrasiveness of the substrates worked. A well-maintained foam disc kept clean between uses typically delivers many wall surfaces of floating work before performance drops noticeably. The point of replacement is when the foam loses flexibility or develops visible tears — both reduce the float quality the pad was bought for.