The depth determines how deep the drill enters the part. It also determines whether the hole is blind (does not reach the opposite surface) or through (passes the part right through) — iFurn.pro determines this itself.
The «Depth» field
The depth is entered in the «Depth» field as a number in millimetres or as a formula — there is a formula icon nearby with the same variables as for the coordinates (see the article «Hole coordinates: origin, X and Y»). A comma and a dot are equivalent as the decimal separator. The depth is measured from the surface into which the hole is bored, inward into the part.
Blind or through — determined automatically
iFurn.pro compares the given depth with the part's size along the axis the drill travels, and decides itself whether the hole is blind or through:
- into the face (the face or back surface) — the thickness axis: if the depth is greater than or equal to the part thickness, the hole is through, otherwise blind;
- into the top or bottom edge — the width axis (Y): through, if the depth reaches the part width;
- into the left or right edge — the length axis (X): through, if the depth reaches the part length.
The hole type is visible right in the diameter list: each option is labelled «blind» or «through» (for example, «8 mm blind»). So the technologist sees at once what will result at the current depth.
How the actual depth is adjusted
The entered depth is a reference; the actual drilling depth iFurn.pro adjusts to the real geometry of the tool and the part:
- Through hole. The drill is conical, so for the hole to come out clean across the whole thickness, the depth is increased: the actual depth equals the part thickness plus the drill diameter — the cone of the drill fully exits the part.
- Blind hole. The minimum remaining body of the part is taken into account — how much material must stay under the bottom of the hole (set in the company's admin panel). If the entered depth leaves less than this minimum, it is automatically reduced so as not to weaken or break through the part.
Why it matters
Blind and through holes are bored with different drills, so the type determines the list of available diameters: for a through hole only a tool able to drill all the way through will fit, for a blind hole — a tool for blind holes, and in both cases the drill must reach the given depth. In detail — in the article «Diameter and the company's drilling tools». If the needed diameter is not in the list, a frequent cause is too great a depth for the available drills.
Glass
For glass parts the depth is set automatically — one millimetre more than the thickness, that is the hole is always through. Blind holes are not bored in glass, and the diameters are taken from a separate production parameter of the company, not from the usual drill list.
Depth tips
- For a through hole into the face it is convenient to set the depth with the formula
z(equal to the part thickness) — the hole is guaranteed to go through at any thickness. - For a blind hole the depth is set smaller than the size along the drilling axis — for example, for a hinge cup or a shelf support.
Next
After the depth, the hole still needs a drilling side and a diameter — these are covered in the articles «Drilling side: face and edges» and «Diameter and the company's drilling tools».