A4 scoring board

I needed to score some card to make last-minute Valentines cards. Apparently the proper way to do this is to lay the card over a "scoring board" - a board with a channel cut in it - and to then run a blunt knife over the channel, using a rule as a guide. The wrong side of a butter knife works as the scoring blade, but what to do for a board?

Enter this print!

This is a simple sheet with a 1mm x 1mm groove cut in it, long enough to score the short side of an A4 sheet (to make an A5 card). It has a small guide along the top to help get the card lined up straight.

It worked well using a butter knife on some 310GSM lightweight card stock, I have made a couple of cards with it today.

Use 100% infill. Print time was around 2 hours 35 minutes. I had to print it diagonally to fit in the bed of my Ender 3.

The CAD is here:

https://cad.onshape.com/documents/fc816c6b7f11ec215bc17449/w/2a90e59e4186a349143acf4b/e/f020aa150e6ac250091ae29a