Every family has a photo from last Thanksgiving: everyone squeezed into the frame, somebody blinking, the dog in front. It gets posted once and forgotten. Printed as a jigsaw and put on the table after dinner, it becomes the thing people remember from this year, because for half an hour three generations are leaning over the same picture arguing about where the dog goes.
This is the easiest 3D printed gift to get right, and the one with the shortest list of things that can go wrong. Here is that list.
The photo: fewer faces, bigger
A relief print has four to eight tones, so a face needs to be at least a few centimetres wide in the print to be recognisable. For a group of eight on a Large puzzle (210 mm) each face is about 20 mm, which works if the faces are close together and well lit. For a group of twelve, go Ultra (250 mm) or let the generator split the puzzle across two plates and print it twice as big; the pieces interlock across the plate border like any other pieces.
If the only photo is a wide shot with tiny faces, crop to the people in the middle, or make two puzzles: the kids' table and the adults' table.
Pieces: match the youngest and the oldest at the table
A puzzle that everyone builds has to be solvable by the eight-year-old and comfortable for Grandpa. In the Universal Puzzle generator set the piece count yourself: 80 to 100 pieces on a Large puzzle gives pieces around 20 mm, which is big enough for both and takes a group about twenty minutes. Save the 300-piece version for the person who wants to keep it busy over the weekend.
Timing: print it the week before
- Generate and look at the preview a week before: if the faces read in the preview, they read in plastic. Fix contrast there, not on the day.
- Print the puzzle on an evening before the 20th: a Large is an overnight print, about 8 hours with four colours.
- Print the frame with the stand the next evening (about two hours). It is where the puzzle lives after dinner, on whichever grandparent's sideboard wins the argument.
- Bag the pieces, hide the preview, and put the bag on the table with dessert.
If the family is spread across the country, print one puzzle per household and send them in the week before; the print schedule shows how three or four fit into one printer's week.
The extra: what everyone is thankful for
Record each person at the table saying one thing they are thankful for, ten seconds each, and print the sound waves as small plaques with names. The soundwave generator is free and a plaque prints in about half an hour; next year's table gets last year's voices. The puzzle photo, the recordings and the frame are all made from things you already have: one photo, one phone, one printer.