centre finder

[bill howes]

In need of a centre finder primarily for lathe work, I went to google and found this
Ames square.jpg a centre finder/ square patented by Ames in the 1800's.
There were a few false starts in making a reproduction , but it has become my go to on the workbench accurate enough for everything that I do.
20180511_171846.jpg

As a centre finder20180511_171619.jpg
As a square20180511_171742.jpg
And to draw a 45*, or to square an inside corner20180511_171641.jpg
Turns out that Ames had many patents including one for a moving staircase, the precursor of the escalator
Regards
Bill Howes
Not sure why pictures are rotated 90* countrclockwise. Suggestions

[Mike Henderson]

You may be aware of this, but most combination squares have a center finding head. Here's a standard, 12 inch, combination square (Mitutoyo) with the center finding head and a protractor head.
Center-finding-head01.jpg

This is the way you would use it to find a center, with just the center finding head.
Center-finding-head02.jpg

They make center finding heads for just about all the sizes of combination squares, all the way up to the Starrett H8 squares. I think that's the model number of the big square - anyway it has a 24 inch blade and the normal head is about 8 inches.

Mike

[steven c newman]

Have three that fit onto a rule, like that....one is a Starrett...

Hate to say this, but...You can walk into Harbor Freight....and buy their "package deal" Throw away the combo square and stash the protractor....and use the center finder that is left...

[Tom Stenzel]

Nicely done, Bill. Homemade tools rule.

What is the tongue made of? At first I thought it was painted metal.

-Tom

[bill howes]

Nicely done, Bill. Homemade tools rule.

What is the tongue made of? At first I thought it was painted metal.

-Tom

I'm not sure what the tongue is Tom. A piece of reddish extremely hard wood that was on the sole of a flea market wooden jointer.
I do have a conventional centre finder Steven, but this all in one design was appealing.
HF hasn't invaded Canada but we do have Canada Tire as a source of off shore tools
Bill

[Peter Christensen]

Bill, Princess Auto is the closest kind of store we have to Harbor Freight. Canadian tire is a few levels higher in quality and price.

[steven c newman]

Back when I was doing a lot of spindle work on the lathe....used a pair of 1/2" by 3/4" scraps To make an "L" shaped jig.....added a piece of 3/8" plywood, cut with a 45 degree. Like a Right Triangle....Added the along one side of the "L", with the apex of the triangle down where the corner of the "L" was. Could set about any size blank into the jig, draw a line along the angled part. I usually made a few lines, to make sure things were centered...

Have no idea where the jig is now....been a while since I even used a lathe..

[lowell holmes]

I have a Starrett with a center finder. It's a great square.

[Chuck Nickerson]

That's a nice form of layout tool. I can picture three different sizes that will be useful in my shop, especially if I mark or inlay a ruler along the tongue.

[bill howes]

That's a nice form of layout tool. I can picture three different sizes that will be useful in my shop, especially if I mark or inlay a ruler along the tongue.

Or even use a flea market metal ruler. I didn.t have one hand or I would have. As to different sizes I found that the larger the size was the easier to was to build to high accuracy.