Hello Creekers,
I had a project making and engraving two acrylic book slipcases from 4.5mm clear acrylic. The internal dimensions were 311x320x36mm with an open end 311x36mm and some text engraved on one of the large panels. So far so good… however they also stipulated optically clear 100% defect free joints using 45* mitred edges. Challenge accepted.
I laid out the flat pattern and cut the acrylic with a 45 Vbit on the CNC router, made an extra just in case. Collected my panels made some 45* sanding blocks from 15mm MDF and cleaned up the all the edges with 320 to 800grit. Satisfied my edges were smooth and straight, cut some assembly jigs from acrylic on the laser and proceeded to fail miserably assembling the cases.
I could get almost perfect edges on part of the joins, before fifth side was in in place, but when trying to join the 5th panel, I could not get my hand/applicator in to reach joins, so I tried to let the solvent run along the edges and capillary itself into the joint, no good. Next box I tried form the outside of box. this just made a mess and has solvent glue dripping along panels…Fail
I tried again this time trying the taped hinge method, while this looked quite easy in the YouTube video and for the most part was easy the edges were far from bubble free.
Now I’m on the phone, talking to local acrylic suppliers/mfg’s asking how they do it. In short the answer was we don’t/can’t do 45* museum quality edges, but one suggested it could be done using UV glue. So $130 and two days later a couple of 50ml bottles of UV glue arrive, one water thin and the other similar to light oil. I cut out 3 more boxes and once again proceeded to fail miserably.
Dead line looming, I tried to pull a sneaky and deliver a box with butt edges using the UV glue. The joints were perfect with the slightest fillet along the joints of fifth panel where I had to let the glue drip along the join from the open end. The customer was impressed, but rejected the job due to not having 45* mitred joints.
Has anyone been able to achieve a 45* mitre edge joint that is museum quality ( bubble free, optically clear ) on a box of this size with only assembled opening measuring 36x311mm? IF so would you mind sharing how you were able to accomplish this feat of acrylic mastery?
Many thanks in advance.