Part a ring into head and shank

WhereThe top bar: the row of words that begins File, Edit.

DoDownload p4-10-start.blend from Files above and open it. Then choose File > Save As and save it under the name below, in a folder of yours. Open an exercise file and keep the start file safe (P0-07) shows how.

Typemy-ring-parted.blend

You should seeThe 3D view shows a ring from a little above: a gold band with a pale round stone held in four claws over its top. It is one body, so nothing stands apart. The title bar, the strip above File and Edit, begins my-ring-parted.

It worked whenThe title bar, the strip above File and Edit, begins my-ring-parted.

WhereThe section bar, Check, then the panel Reports & Checks. If the sidebar is shut, press N with the pointer over the 3D view.

DoClick Check, then open Head and Shank by clicking its title.

You should seeThe panel’s first line reads “Body: CJ_Head_Fused_CJ_Gem_Round_5.00x5.00”: the body it will part, the selected one. Under it stands a box, Head region (mm), with a menu that reads Collar as Foot.

It worked whenThe first line of Head and Shank begins “Body:”.

WhereThe box Head region (mm), the menu that reads Collar as Foot.

DoClick the menu and choose Above a Height.

You should seeThe box now holds one number, Height: everything above that height on the head’s axis is the head. Collar as Foot is for a head with a collar under it, and this head has none. Fitting Gap reads 0.00: the add-on’s words for it are “line to line”, with no gap left between foot and seat. Cut Clear By 0.002 is how far outside the surface the cutting region stands: leave both. With Collar as Foot left on, Measure Parting says “The foot’s flat bottom (0.00) must lie above the collar’s bottom (0.00)” and measures nothing.

It worked whenThe box holds one field, Height, and no collar fields.

WhereThe box Head region (mm), the field Height.

DoClick the middle of Height once, type the number, and press Enter.

Type11.61

You should seeHeight reads 11.61 mm. A height here is Z in millimetres, read up from the grid. The prototype of P4-09 cut a ring like this one at the foot plane, 11.66, where the four claws end. The second rail, the lower of the head’s two rails, ends higher: its underside is at 12.01, 0.35 above the foot plane. So 11.61 stands 0.05 under the foot plane (the add-on’s own offset, which makes the cut certain to pass through the claw feet) and 0.40 under the second rail: it cuts the four claw feet and no rail. The second picture marks the levels. Any Height from the foot plane up to just under the second rail’s underside cuts the claws and nothing else.

It worked whenHeight reads 11.61 mm.

If it goes wrongThe parting cuts a rail of the head: the height is above the second rail’s underside, 12.01 here. Type a number under it, such as 11.61, and measure again.

WhereThe panel Head and Shank, the button Measure Parting, under the box. Scroll down if it is out of view.

DoPress Measure Parting. Wait: the add-on cuts a copy to measure it.

You should seeA short list under Split Head and Shank: the head’s volume, 21.9524 mm3, the shank’s, 465.6805 mm3, and a joint of 4 surfaces, 2.617 mm2 of contact. The joint is where head and shank meet: four surfaces, one for each claw. Nothing is cut: the button measures and changes nothing. A fuller list stands in the Text Editor, under CJ Parts Read-Back. In the picture, the line marked 4 is the one this step reads: further down the same list reads “Least metal at the joint”, head 0.84 and shank 0.35 (millimetres, this run’s reading). The shank’s 0.35 is how deep the claw feet are rooted in it. That is under the 0.60 least for structural metal, and the add-on does not flag it, so you must: a joint of four feet this thin is a practice joint, not one to cast, which is why a production joint is a tongue and groove. The list also says “Lifts straight off, can turn”: nothing keys the head in its seat, and the add-on’s own note is that a peg, a flat or lips are yours to add. A higher Height roots the feet deeper: Try it yourself reads one.

It worked whenA short list stands under Split Head and Shank, and the file has no new body.

WhereThe panel Head and Shank, the button under Measure Parting.

DoPress Split Head and Shank. Wait for it.

You should seeThe short list reads again, now for the cut that was made. The file now holds a head and a shank, two closed bodies in the collection CJ Metal, and the fused body, kept untouched as the one-part form in its own collection. The head and the shank lie in place, so the ring looks the same.

It worked whenThe box Both forms reads “Head, shank and one-part body”.

WhereThe 3D view. The picture shows the head lifted off the shank, for this picture only.

DoLook at the picture.

You should seeThe head’s four claws end in four flat feet, and the rails stand whole round them: the cut fell across the claws only. There is no tongue on the head and no ball or collar at its foot. The four flat feet add up to 2.62 mm2, the contact of step 5: 0.65 mm2 each, about 0.91 across. At the bench the head is joined to the shank at these four feet, by solder or laser, after the head is cleaned and the stone set.

It worked whenYou see four flat claw feet and unbroken rails.

WhereThe panel Head and Shank, the box Both forms: the button Print Check Parts.

DoPress Print Check Parts.

You should seeThe box reads “Print check: 3 of 3 bodies pass.” and three lines, one for each body, each “closed, one body” with no pair of faces crossing. The check tests every face of the three bodies against every other. “3 of 3 bodies pass” says that each body is closed and sound to print. It says nothing about strength, or about whether the parts fit. Export Both Forms refuses a file that fails it.

It worked whenThe box under Both forms reads “Print check: 3 of 3 bodies pass.”

WhereThe box Both forms: the button Export Both Forms, under Print Check Parts. The box Name above them reads ring.

DoPress Export Both Forms. Wait for the files.

You should seeThe box reads “Both forms written to” and your folder, then “4 files, each read back.” The files stand in the folder of your saved copy: one_part_prototype holds ring_one_part_mm.stl, and two_parts_production holds ring_head_mm.stl and ring_shank_mm.stl, in millimetres, with a short notes file. Where Folder is empty, the files go beside the saved file: that is why step 1 saved your copy.

It worked whenThe box under Export Both Forms begins “Both forms written to”.

WhereThe 3D view: move the pointer over it.

DoPress Ctrl+S.

You should seeBlender writes your copy at once, with no question, because the file already has a name. An asterisk, *, in the title bar marks changes that are not saved, and it goes now. Save your work and get it back (P0-12) says more about saving.

It worked whenThe title bar begins my-ring-parted and carries no asterisk.