Don’t forget to try a sample of the stitches first.

I believe the back will have zig zag stitches when a double needle is used. It’s been a while since I used them.

zigzag will be strage :) though i dont carre how it looks but let me see if i can do settings 1st, manual is bit unclear to me as it says select stitch that supports double needle ... em well like i know which one does, though i needs mad simple application
i just ordered needles but will see if i can concur settings now

Yes, double needles will have a zig zag on the back. There is only one bobbin thread so it has to catch the thread from both needles.

Interesting . . . What Bernina's do you have that have side loading bobbins? I've had 5 and all had front loading bobbins.

oh so once i see in car upholstery use 2 bobbins or something? as when i see whats on back of car seats its straight lines and i know they use 2 needles and separation guide in between so it follows exactly in center of 2 sheets stitched togather

I am pretty sure mine have the same configuration as yours do. I was thinking side loading ones meant just not the drop in top...but I see what you mean. My long arm has a side vertical bobbin while the berninas would have a front loading vertical bobbin while my Vikings had a top loading drop in bobbin. Yikes. Terminology. I don't even know if I am using the right terms now. I would have to draw pictures! Or would the long arm and the Berninas have a front loading vertical bobbin as the bobbin opening faces me as I use the machine well the Berninas are in the cabinet sideways and the longarm is on the frame nose pointing at me.

Yes, the industrial twin needle machines used in auto upholstery have 2 bobbins, one for each needle.