Size and Type is up to your preference, but I used 1/2"x3"x24" poplar boards
12v wallwart with male 2.1mm connector was used
Warm, cool, white, rainbow, RGB; whatever you decide you want to use. Cool white was used on this frame
Or just wire the wallwart directly
Don't use plumbing solder
Half by three (1/2x3) Poplar boards with 5/16 quarter molding board cut to the length of the poplar boards. VW engine heads and disc brake rotors used as weights for gluing.
The quarter molding is glued to the boards with the curved edge forward and facing out. The weight is left on the boards for 4 to 5 hours. Wait long enough for the glue to develop a strong bond before proceeding
The board is cut at a 45 degree angle. (While straight cuts can be done instead this guide does NOT account for the changes needed.) The board is positioned with the quarter molding facing out, but the saw is adjusted so the quarter molding will be pointing inward when assembled. You need to pay attention to the cuts you make , cutting the 45 degree the wrong direction could force you to startover or make a smaller frame.
As said in the "Tools needed" list, you do not need a mitre saw. A mitre box and hand saw or a pull saw and some patience can also preform the cuts. More attention will be needed so the cut are even but otherwise the outcome will be the same. I, personally, used a mitre box and hand saw before deciding a mitre saw was a good investment.
Clamping and gluing should be self explanatory. Driving screws in not necessary, but recommended. My glue says it is not intended for load bearing, probably for heavier loads but maybe the screws will keep the frame from breaking if it falls off the wall.
I have my glass cut at lowes to 1/8" smaller than the final dimensions of the now assembled picture frame. I don't cut my own glass and i don't intend to ever. At the time of writing Covid-19 has made it harder acquire glass. So the guide continues without glass and therefore the frame is left incomplete.
Left are the female 2.1mm DC connectors and right is a reel of LED tape
This is pretty much just common sense at this point. Solder the LEDs, wires and connectors together.