Countersinking for a confirmat is a small widening at the entrance of a through hole into which the head of the confirmat (a furniture tie) sinks. Thanks to the countersink the head sits flush with the part surface rather than protruding above it.
Where it is
The countersink is set not in the hole-adding form but on an already added hole — in the part's operations list («Operations history»). Next to the hole there is a compact icon switch that is responsible for the countersinking.
Three options
- Countersinking for a confirmat from the face — a widening on the side of the face;
- Countersinking for a confirmat from the back — on the side of the back face;
- No countersinking for a confirmat — an ordinary hole without widening (the default option).
The countersink side is the side of the part from which the confirmat will enter and its head will sink.
When the switch appears
Countersinking is not shown on every hole. The switch is visible only when all the conditions match:
- the company has enabled countersinking for confirmats (a production parameter);
- the hole is through and made into the face — the front or the back (there is no countersinking for edges);
- the hole diameter equals the confirmat diameter set by the company.
If the hole is blind, in an edge or of a different diameter, or the company has not enabled this option, the switch is not shown.
The countersink diameter
The size of the countersink itself (its diameter) is set by the company in the production parameters — it is the same for all confirmat holes. In the project the technologist chooses only the countersink side (or its absence), and the widening diameter is substituted automatically.
The countersink depth is now also set in the production parameters instead of being fixed: different confirmats need a different head-sinking depth, and the CNC program is generated for the exact hardware the shop works with.
Why it is needed
A confirmat pulls two parts together, and its head must sit flush — otherwise it will hinder the fit or be visible. A countersink from the right side solves this neatly and uniformly across the whole order.
Next
Countersunk holes are ordinary through holes of the confirmat diameter, so they can be copied, mirrored and changed in bulk together with the rest of the drilling (see group processing).