Does anyone know what these thickness gauges are for?

[Debcrow]

Does anyone know what these thickness gauges are for? They are 1.5 inches long. The radius and slot size is the same on all of them. Why oddball thickness (.032, .059, .027, etc.)? Thanks in advance.

 

[kd3pc]

spark gap tool

 

[Debcrow]

I thought that, but I would have thought the slot would be near the end where you could actually use it to bend the electrode not way up the side.

 

[kd3pc]

was taught to make the bend on the side of the electrode and then measure/remeasure or rebend.

best

 

[lis2323]

was taught to make the bend on the side of the electrode and then measure/remeasure or rebend.

best

Same. [emoji106]

 

[Oldtuleguy]

spark gap tool

+1

 

[Debcrow]

That's what I was taught also. So how do you use the slot on this to bend the side when the slot is 3/8 of a inch up the side of the gauge? As a side note these gauges range from .002 to .072.

 

[Oldtuleguy]

Hmm.. 002 is pretty thin. Maybe its for something else...

 

[Debcrow]

Perhaps a picture will help to show what I am talking about. Most plugs I ever had to gap were closed up (sometimes from mishandling in shipping) and had to be opened wider. As can be seen from the photos the slot in these is pretty far from the end and the blade would have to go in-between the electrode to open the gap up. I cannot imagine trying to open up a gap with a .008 feeler gauge thickness if that's all that would fit in there.

 

[Oldtuleguy]

I see what you mean

 

[DFB]

Looking at the last photos if you passed the blade over the center electrode does the notch fit around the outer ground electrode? Maybe to ensure your flat and square in the measurement

Cant say I've seen any others like it in my time

Nice looking set though

 

[MrSurly]

I think it's fairly clear that these are NOT for spark plug gapping. They certainly *could be used for that, but the slot is for some other purpose, not a plug gapping pry tool.
I'm thinking that there's some machine that has adjustable elements that have a central protrusion that the slot goes around, or say, a central rod or some such.
Are there any wear patterns or scratches on the tool to indicate usage?

 

[larry_g]

I've used similar for stops in a press machine. Think like a small arbor press that you want to press in a pin to a specific height. Insert the shim to stop the downward motion and set a specific height for the pin to protrude from the surface.

lg
no neat sig line

 

[Debcrow]

I do not see any wear marks on them. Pressing something in to a specific height kind of makes sense. All the slots are the same width so it would have to be a fixed size pin. I cannot imagine anything that would require such a range of pin depths unless it was made for something very specific, which is possible.