Description
The DED77674 polystyrene disc is Dedra's floating disc for the DED7767 plaster power float: a polystyrene working face for floating and smoothing lime-cement and gypsum plaster. It fixes to the machine with hook-and-loop, like the other DED7767 working discs in the DED7767 disc and sponge range, and it is bought separately from the machine.
What the DED77674 Polystyrene Disc Is Made For
Dedra's catalogue entry for this code calls it a Styrofoam disc in English and a tarcza styropianowa, a polystyrene disc, in Polish. Both describe the same job: floating and smoothing lime-cement and gypsum plaster, with the disc held on the float by four strong hook-and-loop fasteners.
That is finishing work on fresh plaster, not preparation. Taking old paint, wallpaper and unevenness off a wall is the job of its sister code, the DED77675 scraping disc, which carries steel blades instead of a soft face.
DED77674 Data From the Dedra Catalogue
| Property | Value |
|---|---|
| Code | DED77674 |
| Barcode (EAN) | 5902628776747, the same on the Renders World listing |
| Working face | Polystyrene (Styrofoam in the English entry) |
| Declared use | Floating and smoothing lime-cement and gypsum plaster |
| Fixing | Four strong hook-and-loop fasteners |
| Diameter | 400 mm (description); 390 mm (attribute field) |
| Recommended for | Dedra DED7767 plaster power float |
Thickness, weight and a hardness grade are not given in either language, and Dedra names no machine other than the DED7767 for this disc.
- Two diameters: the entry prints 400 mm in the description and 390 mm in the attribute table, in both languages, with no explanation. The manual gives the machine's own disc as 390 mm.
- How to order: by the code and the barcode, which identify the part whichever figure is quoted.
Three Floating Discs for One Machine
Dedra's catalogue gives the same declared use, floating and smoothing lime-cement and gypsum plaster, to three working discs for the DED7767. What separates them in the catalogue is the material of the face.
- DED77674, polystyrene: the disc on this listing.
- DED77671, flexible polyurethane foam: graded medium-hard in the Polish entry; see the DED77671 foam disc.
- DED77670, PVC: plastic, named as PVC in the Polish entry; see the DED77670 plastic disc.
The catalogue does not say which of the three to choose for which plaster or stage, so no ranking is offered here. The DED7767 manual adds one line on the discs that come in the box: the plastic disc with mesh is for larger irregularities or plaster that has dried out too much, and the sponge disc is for the finishing pass.
Why the Manual's Accessory List Reads Differently
The DED7767 manual lists three accessories for separate purchase: DED77671, DED77674 and DED77675. In that list the wording attached to DED77674 and DED77675 is the reverse of the catalogue, with DED77674 described as a disc with a ripper. The catalogue entry for each code carries its own product image, its own barcode and a description of the tool itself, and the barcode of this entry is the one on the Renders World listing. The catalogue is followed here.
If you are replacing a worn disc, order the code on the disc; if you are buying a first one, order by the code and barcode above rather than by the manual's wording.
Fitting the Disc and Running the Machine
The manual's sequence applies to every working disc, the DED77674 polystyrene disc included, and every step before the start is done with the machine unplugged.
- Fit the trowel disc onto the spindle, its hole matched to the shape of the spindle, and tighten it with the screw.
- Press the polystyrene disc onto the trowel disc by its hook-and-loop face, so that all four fasteners hold.
- Check the supply voltage against the nameplate before plugging in.
The Dedra DED7767 plaster trowel is started horizontally and without load, and it reaches full speed before it touches the plaster. It is then guided in semicircular movements, with the pressure matched to the work, and the plaster may be moistened where needed. It runs at 110 min⁻¹ on a 710 W motor and is rated for S2, 15 minutes of continuous work; hearing protection is required whenever it runs. The Renders World guide to finishing with a power float covers the rest of the sequence on site.
The manual asks for the working disc to be looked over for wear before each use, and it gives low working efficiency as the sign of a worn disc.
Ordering, Delivery and Returns
Orders are processed the same day when the disc is in stock, and delivery is not calculated at checkout: the Renders World team quotes it after the order comes in.
- Courier: small parcels up to 25 kg go on a next-day service, and every delivery is kerbside.
- Collection: Unit 9A, Central Trading Estate, Southampton SO14 5JP, Monday to Friday 7am to 5pm and Saturday 7am to 12pm.
- Returns: a change-of-mind return runs to 14 days, with the disc in its original condition.
DED77674 Questions Buyers Ask
Does the DED77674 fit machines other than the DED7767?
Dedra recommends it for the DED7767 and names no other machine. For any other float, check that machine's own documentation first.
Is a polystyrene disc included with the DED7767?
No. The box holds the machine, the trowel disc, a plastic disc with mesh, a sponge disc, screws, a screwdriver and brushes. The DED77674 is one of the accessories the manual lists for separate purchase.
Which plasters is it made for?
Lime-cement and gypsum plaster, for floating and smoothing. The catalogue names no other material, so for anything outside that, ask before ordering.
Will it take off old paint or wallpaper?
No. That is the scraping disc, DED77675, with six steel blades. The polystyrene disc works fresh plaster.