Sorry going to be a bit of quilt police here, NEVER EVER SEW OVER PINS! When the vintage machines were built they were beautifully machined and manufactured and would sew through an iron sheet if you asked it nicely BUT with all the bells and whistles us quilters, and other sewers now expect in our modern machines you now have a far more delicate animal with swing arms, computer bits n pieces etc. etc. and they won't stand that sort of wear. Sew over a pin on a modern machine and you risk completing ruining the "timing", besides other things of the machine and however good your lovely service man is it will never be as you bought it ever again.
How do I know, I saw a member of my quilting class sew over a pin on a brand new £500 Singer machine, modern one, and she had to give it to her children to play with, good side of the story she picked up a lovely old Singer for £20 in a car boot sale and loves it to pieces.