Jig For Measuring Arch Height of Assembled Instrument
Posted 13 June 2012 - 10:43 AM
Here's how it works. It's made like spool clamps but square. I put one on each side of the instrument aliened with where I want to measure the arch. The clamps are covered with thin leather on the clamping surface. There's a straight ledge cut in the face of each top spool. I lay a straight edge in the ledge and clamp it in place. It's 18mm from the top edge of the plate to the bottom edge of the straight edge. If the plate is 4mm thick I add that to the 18mm ( 18+4=22mm ). I then use a small m m ruler to measure from the bottom edge of the straight edge down to the arch. In this case it's 7.5mm. I then subtract the 7.5mm from the 22mm to get the arch height of 14.5mm. It's a pretty simple jig, but it works very well.
Posted 13 June 2012 - 11:59 AM
Posted 13 June 2012 - 12:12 PM
Interesting, but how do you know the plate thickness?
Posted 13 June 2012 - 02:43 PM
I like your cut out. Same principle as my jig. I've had my jig for several years. I have no idea where I got the idea for it. I have a collection of old Strads that go back to the 1950's so it may have came from there.
My minimalist approach to this is in an old thread: here.
Posted 14 June 2012 - 02:37 AM
This is only for measuring the arch height.
I know, but you say you add 18 mm to the top thickness. Where do you get those 4 mm?
Posted 14 June 2012 - 05:22 AM
It's the edge thickness.
1 user(s) are reading this topic
0 members, 1 guests, 0 anonymous users