Install of alu-composite sheets to cinderblock wall - best method?

[BetaCtz]

I am going to have two 4' x 8' sheets of 1/8" aluminum composite panel mounted flush side-by-side on a painted cinderblock wall.
They will then be covered with a printed vinyl mural. I am electing to install the vinyl after the panels are mounted so that I can ensure a perfect visual seam of the graphic. ie. one image across two panels.

I could hammer drill and use concrete screws/anchors, but I'd like to keep the heads invisible.

Criteria: Holes in walls are fine, but would prefer to not use adhesives in case the panels need to be removed.
Install is happening from ground level.

Best hardware or method to mount for long term use, but minimal damage to the walls, whilst making the graphic appear to not have 8 screw holes through it?

I was also thinking of using a "strip" connecting panel on the back of the two panels, to bring the boards together to ensure ZERO gap in between the boards.

Thanks in advance.

 

[unclebun]

We usually install aluminum composite panels with truss washer lath screws, which have a very low profile head. I find that with a predrilled 1/16" hole to start them, I can screw them right into cinderblock. The screw head isn't invisible or completely flush, but it's much smaller than the big hex head tapcons.

 

[BetaCtz]

With the french cleat adhered the to panel, I'm guessing a high bond VHB tape should be able to hold the weight of a 4' x 8' panel?
ie. I could do an 18" or 30" french cleat per panel and so long as I've measured evenly, should be able to get them hanging nicely side-by- side.

With the lathe screws, also not a bad idea.

I think it comes down to if the client cares that the screws are hidden or if a literal lift and pull off the wall is what they want.

Thanks for your help

 

[klingsdesigns]

We did this before and debated on tape or screws. We painted heads of screws and not noticeable 10 ft away.

 

[JTBoh]

Best way, per request:
Mount 1" aluminum tube to wall. Drill one large hole on the side of the tube facing out to accommodate the Tapcon/washer, and drill tapcon sized hole on the rear facing wall and mount washer + tapcon. Completely hides the screw within the tube.
You can probably get by with 3x verticals and no horizontals. VHB on full surface of the outer side of the tube.
Chip highpoints in mortar to help make it flat, if needed.

If you want to make it fancy, weld it all together/paint it/mount it in one piece. This is the absolute best way for longevity, strength, and aesthetics.

 

[petrosgraphics]

signcomp makes a frame system that you mount to the building , slide the faces in and have 1 side of the frame removable. the best is there are no open spaces on the panels for the wind to get in. nice and neat with just the screws holding the end runner in.

 

[JTBoh]

Just to follow, you mount your frame & then vhb the panels to the frame? I can see it working, but without some finesse on the tape, you could end up with a crooked panel, and since VHB>ACM, you'll have a heck of a time saving the panel...

I've screwed a 2 x 4 to the bottom of the frame as well - gives a shelf for the ACM to land on while aligning the seam.