Center scribes

[GRapp]

I've used a drill bit with unsatisfactory results. Yesterday I made an adjustable one and it seems to work ok. Today I saw the kind with 2 guide rods and the scribe in the middle and the similar version with bearings. What do you pros use and why?

 

[polish avenger]

I'm no pro, but I do like an accurate line. When I'm in the mood, I use a height gauge with carbide scribe on a surface plate...otherwise, a hardened dial caliper works just fine.

 

[Stacy E. Apelt - Bladesmith]

I still use an old Jerrod Todd center scribe with a carbide point. There are several available from the knife parts suppliers, and places like Uncle Al's and

 

[navman]

I rece try bought an import dial caliper with carbide jaws. Scribes a nice crisp line, even on hardened S90V.

 

[Cliff Carter Knives]

height gauge with carbide tip and surface plate. I wrestled with the small scribes forever, the height gauge/plate setup is light years more efficient and more repeatable.

 

[Stacy E. Apelt - Bladesmith]

This is simple and easy to make:



This is a JT scribe. It takes a little getting used to but works well.

 

[Fiddleback]

Dude get a height guage. All those machinists can't be wrong. A surface plate and a height guage do more than just mark a center line. They tell the truth. If your blade isn't straight, they will let you know.

 

[Fiddleback]

Fyi, my surface plate and height guage are my favorite tools in my shop. I like scribing the edges when its EARLY. The shop is quiet. No one has showed up for work yet. I find the clicking sound of the steel on the granite to be calming. There aren't any vibrations, no dust, and I get to sit during this task. This is my favorite part of the process.

Sandblasting is my least favorite. I hate that machine.

 

[Lorien]

I made a center scribe when I started out, but have been doing my scribing on a surface plate instead. I feel the same way about it as Andy

 

[Drew Riley]

I've made a handful of adjustable scribe "jigs" over the years, but after getting a decent Mitutoyo height gage for my surface place, there's no comparison. You can measure the exact thickness of your blank, then cut that in half for an exact center line, or divide by 2, +/- .005" for a .010" spaced set of lines, etc....

I'd get a height gage. Oh, and don't bother with the cheap digital gages. Get a decent traditional dial gage. There's used Mitutoyo's, Brown and Sharps, Fowler, etc... all over eBay for around $100 to $150.
The Shars ones for around $75 probably aren't horrible either.

 

[Lorien]

this thing works pretty good, I can get into all the nooks and crannies. I'll mark a centerline on the piece with a vernier first and then match the height of the scribe to that. Been meaning to make a scribe by grinding a drill bit down