Combined counterbore+countersink

[chrisb]

On sloped or curved survaces it seems sensible for countersinks to start with a counterbore, as in this model from another topic:

Bildschirmfoto 2019-03-05 um 11.24.02.png (15.54 KiB) Viewed 559 times

The same situation can occur with steps, like in this model: https://forum.freecadweb.org/viewtopic. ... 37#p291234.

Currently the hole feature can create either countersink or counterbore, but not both. Is it a sensible feature request to have a combination?

[Jee-Bee]

Yes i think

[chrisb]

Any proposals how others do it? I would like to put a good proposal in the ticket.

[openBrain]

Hi chrisb,

For me the simplest way from the user perspective would be that the "countersink" mode allows the user to modify the "depth" value to add some counterbore (which isn't the case today). Easily said, regardless of the needed coding effort.
Would also give some sense to the 2 different options "countersink" and "socket countersink".
IIRC that's how some other CAD software do.
Regarding the given example, I believe that the biggest challenge is to have the Hole feature working on a curved surface.

[chrisb]

Regarding the given example, I believe that the biggest challenge is to have the Hole feature working on a curved surface.

No, that's no problem at all. I tried and countersink and counterbore work as expected. But you are right. The more I think about it, the more I stand in awe.

[Jee-Bee]

My personal way would be 2 options.

• add counter bore
• add counter sink

Than you always wave both options.

Here some long example in creo. don't know what oudio quality is have no sound atm: https://community.ptc.com/t5/Part-Model ... d-p/489244

[Jee-Bee]

Creo knows the option top clearence what means that (as lang as there is direct material without a gap above the hole) it remove that too. kind of reverse trough all in second direction

[openBrain]

No, that's no problem at all. I tried and countersink and counterbore work as expected. But you are right. The more I think about it, the more I stand in awe.

Found the problem. I did not know how to properly use the Hole feature, and it is very "tolerant" to user failures.
Below is what you get if you just select the curved face and click "Hole" :

bad_hole.png (18.72 KiB) Viewed 485 times

I hesitate to call it a bug or a feature.

Given my new knowledge about the correct usage of Hole, I'd agree with Jee-Bee that this feature shall ensure a top clearance for the hole. IMHO, it should even be the default behavior as this function is mainly to place a screw.

EDIT : Another unexpected thing (from my PoV) that you can see on the above screenshot is that 2 successive Hole features are nested, while I'd think they would be sequent.

[chrisb]

Top clearance seems very natural to me, so from the GUI point ov view there has almost nothing to be changed except that Depth should be enabled for Countersink as well, currently it is disabled. It can be sensible for normal holes in a flat surface too.

Countersink.png (24.74 KiB) Viewed 460 times

This is still to be discussed:
- depth of the hole: is it Depth1 or Depth2
- if it is Depth1, then the bore could be the Depth of the countersink in the GUI
- if it is Depth2, then it might better be called something like "Bore above", and the GUI label should switch.

Edit: I think it should be Depth Hole2+Bore above.

[openBrain]

Top clearance seems very natural to me, so from the GUI point ov view there has almost nothing to be changed except that Depth should be enabled for Countersink as well, currently it is disabled. It can be sensible for normal holes in a flat surface too.

Hi,

From my PoV, enabling Depth for countersink is a different thing that having a "top clearance" option.

1. Depth enabled : your sketching plane is above all, and everything is holed below. User have to place its sketching plane so he ensures that the hole goe through at the head side. Notice that Depth is a digital value.
2. Top clearance : your sketching plane is basically where the screw head will end. Top clearance is only a check box. If it is checked, then the hole will be continued by the software through all solid above the sketch.

I'll try to draft something to make it clearer. Notice that with my meaning, both options may both exist together.

This is still to be discussed:
- depth of the hole: is it Depth1 or Depth2
- if it is Depth1, then the bore could be the Depth of the countersink in the GUI
- if it is Depth2, then it might better be called something like "Bore above", and the GUI label should switch.

I propose to keep the same reference as for the current counterbore (I don't know what it is ).