Boolean operation between a form and a spiral I'm designing a real object: a cylinder box dispender.
It will be 3D printed: two mirror versions of the same object (named Half.shell) will be printed and then screwed or glued together.
Just before gluing/assembling these two parts, I want to insert a thin band of metal between them, and give it a spiral form, so a spiral groove must be made available in the Half.shell object.
Context is Blender 2.9.1 with extra curve add on.
The problem I have is when I want to make the spiral groove into Half.shell object.
I've built a spiral of cubes, starting with a cube, add modifier array of 780 objects, then add modifier curve following an archemedian spiral curve created with the extra curve addon.
I've tried boolean modifier as well as BTool addon to make the difference/groove, with no success: the resulting shape is a real mess with triangles going everywhere and nothing becomes editable from this point.

Edit1:
-the Spiral.of.cubes object sometimes grows by itself, as if I've scaled it on the X &amp; Y axis, and reopening blender can help, but not always. This problem occurs when I'm changing selection in object mode and edit mode.
-so may be the way I'm doing the spiral.of.cube is not the good way.
-Spiral.of.cube is in fact a spiral of parallelepiped 1.5x1.5x2mm
What you need to do :

Select your spiral cube object, delete 2 faces so that it won't generate inner faces, apply both the Array and Curve modifier, press Alt &gt; Merge By Distance:



Fill each tip with F :



The topology of you shell is messy, go in Edit mode and press Alt &gt; Merge By Distance, in the Operator box choose a Merge Distance of 0,001 :



But you also need to delete inner faces, overlapping faces, and you need to recalculate the normals (AltN), especially if you plan to print in 3D.

Once everything done, you can merge all the faces of your shell surface, where the boolean is supposed to happen:




The Boolean will work fine: