Description
The EPS styrofoam hole cutter is INSTAR's STAR polystyrene cutter, code 01-0700: a drill-driven crown that cuts a round pocket around an insulation fixing, so the plug head sits below the board face. It belongs with the insulation plugs and fixings it is used with.
What the EPS Styrofoam Hole Cutter Does on an EWI Wall
In a recessed fixing the board around the plug is cut away, so the plug's disc sits in a shallow pocket instead of on the face. A polystyrene cap glued into the pocket then brings the face back to level. The cutter is the tool that makes that pocket, one fixing at a time.
- A flat face for the base coat — no disc stands proud of the board, so the mesh and base coat go over a level surface rather than over a field of plug heads.
- Insulation in front of the plug — the cap puts polystyrene back over the plug head instead of leaving the disc at the surface.
- A pocket centred on the fixing — the centre point on the crown runs in the drilled hole, which keeps each pocket round and on line with its plug.
Who Makes It: INSTAR STAR, Code 01-0700
The barcode on this listing, 5902846403487, is the one INSTAR, a Polish maker of building hand tools, gives its STAR polystyrene cutter. INSTAR's product entry carries the code, the barcode and a carton of 50 cutters; Renders World sells the EPS styrofoam hole cutter singly.
| Item | What is on file |
|---|---|
| Maker | INSTAR, STAR range |
| Maker's name for it | Frez do styropianu STAR (polystyrene cutter) |
| Maker's code | 01-0700 |
| Barcode (EAN) | 5902846403487 |
| Maker's carton | 50 cutters |
| Sold here | One cutter |
| Board named by the maker | Expanded polystyrene |
| Diameter and pocket depth | Not stated by the maker |
The maker's photo shows the cutter in blue; the shop photo shows a dark one with the same toothed crown and flange. The barcode, not the colour, is what ties this listing to INSTAR's STAR cutter.
Polystyrene Boards, Not Mineral Wool
INSTAR names the EPS styrofoam hole cutter for polystyrene: frez do styropianu means a cutter for expanded polystyrene, and the maker says nothing about mineral wool. The listing title once carried "& wool", and no maker's statement stands behind that word.
- On EPS boards — white or graphite boards from the EPS insulation boards range are the material the maker names, so the cutter is used there as intended.
- On mineral wool slabs — whether plugs are recessed at all is set by the wool system's own fixing instructions, and this cutter carries no claim for wool.
Size: Match It to Your Discs and Caps on Site
INSTAR prints no diameter or pocket depth for the STAR cutter, so the size is settled with the parts in hand before a full wall is cut. Three steps settle it.
- Fix one plug in an offcut — use a piece of the board you are fixing and the plug you will use on the wall.
- Look at the disc in the pocket — it should sit inside the wall of the pocket, not on its rim.
- Try a cap — it should press in and finish level with the board face, without packing or trimming.
The grey graphite EPS plug caps on the same Renders World shelf are sold for recessed plugs, but no document pairs their size with this cutter, so the same offcut settles them too.
How to Use It, Fixing by Fixing
Where each pocket goes is set by the insulation system's fixing pattern, not by the tool; the layout across the wall and around openings is in the fixing pattern and spacing guide.
- Drill the plug hole — through the board and into the wall, to the depth the plug's maker asks for.
- Cut the pocket — put the centre point in the hole, hold the drill square to the board face and cut with steady, light pressure; forcing the crown tears polystyrene instead of slicing it.
- Set the plug — insert and drive it so the disc sits on the floor of the pocket, following the plug maker's instructions for recessed fixing.
- Cap the pocket — clear the dust, glue the cap and press it level with the face.
- Then reinforce — mesh and base coat go on once every pocket on the wall is capped.
What Else a Recessed Fixing Needs
- Plugs long enough for the recess — the pocket takes the disc deeper into the board, so plug length is chosen with that in mind; the plug length calculator shows how length is worked out.
- Caps for every pocket — one cap closes one recess, so the cap count follows the plug count.
- The order of work — boards, plugs, recess, caps, then mesh and base coat, as set out in the EWI fixings installation guide.
Is This Cutter Right for Your Job?
- Yes, if — you are fixing EPS boards with plugs that their maker allows to be recessed, and every pocket will be capped.
- Not this one, if — the wall is mineral wool, or the system asks for plugs fixed flush with the board face.
- Before a full order — one offcut test with your own plug and cap settles the size.
Questions About the Hole Cutter
Can I use it on mineral wool?
The maker names polystyrene only. On wool slabs, follow the wool system's fixing instructions on whether plugs are recessed, and treat the EPS styrofoam hole cutter as a polystyrene tool.
What size pocket does it cut?
INSTAR does not state a diameter or a depth. Some marketplace sellers quote sizes for the same barcode, but those are their titles, not the maker's, so one test pocket in an offcut with your own disc and cap is the reliable answer. That test shows three things:
- whether the disc sits inside the pocket wall;
- whether the pocket is deep enough for the disc and the cap together;
- whether the cap finishes level with the board face.
Does it fit an ordinary drill?
The shop photo shows a shank behind the crown for a drill chuck. The maker gives no shank size or speed, so try it in your chuck when it arrives and keep the speed moderate on polystyrene.
Is it sold one at a time?
Yes. INSTAR cartons the cutter 50 at a time for trade stockists; Renders World lists it as one cutter.
When should the cutter be replaced?
The maker gives no service life. Replace it when the pocket walls start to tear instead of slicing cleanly, because a torn pocket gives the cap adhesive less to hold.