Center Punch Callipers

[Frosty]

Finding center of length with a piece of string. Hold one end on the end of the stock and mark the far end with a pen. Fold it so the end meets the ink spot and the folded string is 1/2 the length. You can fold it 4 8x, 3x and find even fractions.

Find the center of the width with a machinist's square. Adjust it to read 1/2 the bar's width and using the scribe in the square mark the bar from both sides. There will be two lines close enough together to center punch or adjust the square dead on. Always double check from the opposite side. You can mark the center anywhere along the bar or scribe a line down the center by holding the scribe against the end of the rule and sliding both down the bar.

Frosty The Lucky.

[anvil]

My thoughts,, I think finding the balance point is too time consuming and if you don't have a very thin edge to balance it on, opposed to a finger,,, its not precise. 

My way to find the center quickly and with precision, length or width, is to measure twice, once from both ends, mark with a scribe, and split the difference. 

I do all my layout from a centerline, not an edge. Because tapers, scrolls, and curves are so common in our work, the centerline will always give you a true length or measurement. on a curve, the outside edge gets drawn out, or grows in length, the inside edge is upset or shortens up, but the centerline always maintains the original length. Considering this, I get a lot of practice finding centers. 

Generally I use chalk to layout my work on my table but I use a scribe to lay out all my iron. Anything else is not precise enough,,, the lines are too thick. I carry one in my pocket along with my 6' metal folding ruler. Considering chalk is the #1 consumable in my shop,,,   it saves me money.

Precision:  My thoughts here are that its just as easy  to be precise as to be " close enough", might as well work to and challenge yourself to being as precise as you can. its a great skill to have and a real time saver in the long run.  Helps to keep your scrap pile to a decent size as well. With my metal folding ruler and a scribe, working to a 64th" is very doable.   

More times than not, Frosty,,, like minds and all that stuff. I use plastic coated electrical wire rather than a string to measure my curves.

 

[Frosty]

I don't measure curves with string, that's just for dividing long stock if you don't have a tape. I measure curves with a drafting traveler, one is accurate to 0.005" but it's kind of excessive. I picked them up at various garage, yard, etc. sales over the years, the cartography traveler stays with my maps. Heck, I don't usually measure curves after I start them, I have the original measurement if I want to match. 

I grew up with the ingrained knowledge that 1/64" was eyeball range but I haven't done machinist work in years.

Layout is layout, there are lots of ways, some ancient beyond measure like string or modern as tomorrow but it's still layout.

Frosty The Lucky.

[Will Brouwers]

Thanks for all these tips and tricks. Especially the one about measuring and marking from both sides and splitting the difference. That will be very handy! 

[anvil]

Thanks for the reminder about a traveller. I made one long ago and use it as well. Modeled after what the old wheelwrights used. I find that it works pretty well, but have found that the tighter the scroll gets, I lose accuracy. It tends to spin on a point instead of following the curve. I don't know what a  drafting traveler is. 

Will, glad I can help!!  Thanks!

[Frosty]

Below is the "map reader tool" I got from Dad along with the one I used for drafting and metal work. Dad called them travelers but evidently that isn't what they're called in tool catalogues. I'm going to have to do some more searching to find out what you call the darned things. I'll get back when I do, I just hope I haven't confused the tool to the point folks think they're B.S. If you tried the fractional inch instrument you'd love it. They measure around corners, curves, whatever and make 1/64" easy. 

YAY I found the things! Not called travelers for sure! Anyway, I'm not nuts guys though mine aren't digital, heck they're older than I am. These are just images with company names, not a commercial link.

https://duckduckgo.com/?q=plan+wheel+measurer&t=chromentp&iax=images&ia=images

Frosty The Lucky.

 

 

[Irondragon Forge ClayWorks]

I have one like Frosty posted very old and I was told it is a map reader from the War Between the States. It belonged to my Great Grandfather Capt Henry Monroe Haven 23rd Ohio regiment. Never thought of using it for blacksmithing.

[Frosty]

I don't use the map reader for blacksmithing, I use the "plan reader" for measuring steel and such in the shop on occasion. 

Frosty The Lucky.

[anvil]

Cool tool! Thanks, Frosty. I guess I'd call it a mini traveler. Lol, if it rolls like a traveler and "someone" counts the revolutions and you know the circumference, its a traveler.

[swedefiddle]

Good Morning,

I have a small Traveler, that I made. 6" circumference disc plus a Handle using twisted 3/8 round. You can carry it in your pocket. If it is in your way and it falls on the ground, No Problem. No batteries needed.

Neil

 

[Frosty]

Thanks for letting me off the hook Anvil. Sometimes I forget Dad used terms for things maybe 70 years out of date. We could call these self counting travelers and make up our own jargon eh?  Give our students something to pass along to theirs. 

Frosty The Lucky.

 

[anvil]

Lol, I suspect your Dad is correct. My knowledge of a traveler is pretty locked into what I've seen in blacksmithing books.

The one I made is about 8" in diameter and one revolution is about 24". The wood handle went by the wayside long ago and I never replaced it. It was one of my first attempts at a forge welded round ring. Came out pretty round.

[Frosty]

I have no idea where Dad came by many of the terms he used, I'd bet he was given one on a job and called it whatever they did in the shop. I know from personal experience that what we called tools, etc. on the drill crew bore little resemblance to what the makers called them. I found out quickly when we changed drills and tooling and I was given the expeditor hat. I went to every drill tool company in Anchorage and collected all their catalogues in addition to the Operator, repair and parts manuals for the drills. 

Long frustrating stories dealing with that . . . stuff, mostly between our office and supply who was always looking to save a penny no matter what it cost. Our office was using books that were obsolete a couple decades before I got tasked and . . . Nevermind. It took some serous hardball to make both sides do their jobs.

Anyway, for my part here I'll start using the "reader" designation for the measuring tool and "traveler" in that context as a memory of Dad. The traveler you're familiar with IS the blacksmith's trade term and THE one that's appropriate. 

The inch foot "reader" is only really useful in a hot shop where we'd normally use wire or string to measure a thing. If you want to try one out I think you'll like it when it fits the job but be careful to get the scale you use in the shop, fractional inch or decimal inch, they come in both flavors.

Frosty The Lucky.