got to be a CNC machine id say

I would also assume that but it looks like in 2 steps. The red thread is done first then add scrim, then align everything back up and start the black stitching.

Maybe cnc stitching the red then on your scrim you cut out the foam "V"groove around each diamond and thats where you black thread will lay on right on that v groove.

I don't think cnc would do that as there is no doubling up of the thread and as far as I know cnc can only do continuous lines.So my thoughts are the red is done first with the ends being tied on the rear then placed on scrim and the black sewing is done.Shouldn't be too difficult apart from the time to mark out, stopping and starting lines and tying off at the rear.I dont think the scrim is v cut as it looks quite rounded on the diamond edges, I think its more of an optical illusion that it looks squareish.

I believe a cnc quilting machine would be capable of that style stitching for the red with out the double stitching Keith mentioned check out ABM International

But how are they getting such tall diamonds, that’s what I’m wondering.

Thick dense foam?

Did you ask if the will stitch the panels for you if you send in the material.

Yes I did and they won’t without a seat kit order.

This can be accomplished either CNC or Handmade. http://www.relicateleather.com can do it custom or I think Alea Leather and Katskinz have premade kits.

Handmade... Its a puzzle sewing red stitching to vinyl/leather first. Mark your start and go from there moving in Up/Down/Diagonal pattern crossing lines and connecting corners. If CNC can do it without stopping so can we. Black Stitching should already be marked before starting red stitching. Once red top stitching is done add 1/2" sew foam before sewing black diamonds. This would look similar but im almost positive its a firm 1/2" sew foam with a V groove cut out 1/4" deep and 3/8" wide on both sides of black diamond stitch

Cechaflo does it again https://youtu.be/MZZu4nB0kJ8

i'd say the red stitch is done first by cnc on bare leather and the black done with the foam, a cnc machine won't deal with that much foam due to shrinkage.