Official Luthiers Forum!

I have put together a thickness caliper using a deep throat clamp (modified) and an attached a micrometer (typical DIY build). Since I've never actually used one, I am having difficulty reading the dial. When I move the wood, to be measured, around the dial, if I don't keep it perfectly flat (which isn't easy) it skews the dimension like crazy. how do you guys typically approach this issue?

A little practice is all it takes. Set the anvil in one spot and pivot the tool around until you find the smallest measurement, that is the thickness of your work piece.

Yes, you have to keep it flat. That's just how it is because of the geometry. The smaller the tip radius of the micrometer and the smaller the diameter of the anvil (they should both be domed) the less the sensitivity to tilt error, but the more sensitive you are to the tip falling into a "hole". The typical tip radius of the micrometer is usually only a millimeter or so, whilst the anvil may be 3-4mm. The electronic gauges have built in damping so are often slower to read than a mechanical gauge because the electronic ones can take a while to settle.

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Trevor Gore, Luthier. Australian hand made acoustic guitars, classical guitars; custom guitar design and build; guitar design instruction.

http://www.goreguitars.com.au

Mine sits on the bench and I move the workpiece.
I read thickness, about every inch to start with, by first gently rocking the workpiece side to side until dial gauge shows a minimum reading.
Then rock it gently front to back, until dial gauge shows a minimum reading, then check side to side.
Minimum reading is thickness.
Then move to the next spot, repeat.
Gets quicker with practice.

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.