I’m 99% using my shapeoko 4 pro for metal work (probably should look into an HDM at some point), generally aluminum and brass. Typically the stock is pretty small such as 10mm80mm250mm or less. Most of my work is two sided. For a long while I was using either my SMW modular vice or blue tape and super glue. The vice is great but then I need tabs, which complicates my work. Super glue is quick but I’m never confident in it, and more importantly there is no guarantee of the thickness at which the glue will set.
So I have been trying out 3M transfer tape (in particular 468MP. It’s expensive but really quick to use. It’s a guaranteed thickness (0.13mm), so your stock (or flipped piece) is flat in relation to the bit. It’s likely that 3M have a more suitable tape than 486MP and I’ll need to do some research on that. Its shear strength (peel and x/y movement) is crazy.
For sure you need to be careful applying it as it can pucker the adhesive and cause it not to be perfectly flat.
Ps. You will notice that my piece was not perfectly flat across the X, so my Z zero was not constant into the piece, there was a tiny piece of brass under the sacrificial mdf
Typically on the top paths (before I flip) I leave a 0.25mm base layer so I’m not cutting into the adhesive. This leaves me a “foil” of brass that all the pieces are still connected too. The pieces can then be broken into individuals just like taking pills out of foil packaging.
These pieces though, were single sided so I just sanded off the foil thickness, but if you had to flip then you can reapply the adhesive film onto the top surface and flip them all over then machine off the foil on your bottom paths
Also worth stating that I’m using a 300mm wide roll of 3M, you apply to the stock then cut around the stock then press stock onto mdf. So there is no visible adhesive.
