Center Finding T-Square and Rulers

[Renato Tonelli]

OK, I admit defeat. Where do you find these things?

I've looked at all the usual suspects in New York City and I've googled for a couple of hours - nothing.

All I want is a Center Finding T-Square and Ruler (the ones with the ZERO in the center) for easy measurements when I dry mount some prints.

Thanks in advance -

[Richard Wasserman]

Can't help with the t-square, but Mcmaster Carr has the rulers.

http://www.mcmaster.com/#centering-rules/=erdnyk

[Scott Knowles]

Like these?

[Vaughn]

It seems that a centering T-square would have to be custom made for a specific width of mat board. One of the ones Scott linked to would work -- use a Sharpie or otherwise mark your own numbers to create a center zero mark.

[Renato Tonelli]

It seems that a centering T-square would have to be custom made for a specific width of mat board. One of the ones Scott linked to would work -- use a Sharpie or otherwise mark your own numbers to create a center zero mark.

Seems that way - wish I hadn't given up that Zone VI dry mounting jig a few years ago...

[Jim C.]

Renato - Have looked in Dick Blick's in the East Village ?
Last time I was in there they had all sorts of rulers including the Center finding ruler
Pearl Paint may have them too, but they're a shadow of their former selves

A center finding T Square is going to be like looking for hens teeth.

[ROL]

IMO, these devices are crude and worthless for professional looking results. If you can get along without one, or a "jig", this article may have something of use for you.

[Doremus Scudder]

Renato,

I made my own T-square/positioning device. I could also not find anything suitable.

As for the Zone VI mounting jig, I found it much too imprecise for getting a print positioned properly.

Here is what I did/would do:

First, find a T-square that is square and either has a lip that is not much bigger than the thickness of your mat board, or can be ground or filed down to about that thickness. (A T-square that sits half a centimeter above the mat board is no help.) Of course, the T-square needs an accurate scale on the long arm in small enough increments to provide accuracy (mm or 1/16 inches).

Second find yourself a metal ruler (preferably in half scale) with the same markings along both edges. It is up to you if you use metric or inches, but be warned, if you choose inches you're going to have to get good at converting and subtracting fractions.

Now you need to mount the metal ruler on the left horizontal arm of the T of the T-square (viewed holding the "T" at the top with the long arm hanging straight down) with it's edge flush with the measuring surface. You must position the ruler so that the "0" position aligns exactly with the axis of the right (opposite) side of the long arm and so that the ruler reads from right to left (backwards from "normal"). I accomplished this by cutting the ruler down a bit, alternately, you can modify your T-square's "T" to be able to properly position the ruler (important is that the "0" on the ruler align exactly with the far axis on the long arm, not the near one... I hope this is clear, it's a lot easier to show than describe).

The end result should be a T-square with a backwards scale running on the left arm of the "T." If you've done everything accurately, then you have your tool.

To use: position the T-square horizontally on the mat board with the "T" flush and touching the left edge of the board. Position the print flush with the right edge of the mat board and the long edge of the T-square. This should leave a space between the left edge of the mat board and the left edge of the print, which should be easily measurable with the scale on the long arm of the T-square. Simply note this measurement.

Now, take your T-square and position it vertically with the "T" at the top of the mat board. Using the ruler you have added, position the T-square so that the left edge of the mat board is at exactly half the distance of your first measurement (if you use a half-scale ruler, then this is easy, just use the same number. If not, divide your initial measurement by two and use that number. Doing this with fractions is fun and keeps your brain from getting old).

Now, being careful not to move the T-square (you can weight it with a shot bag if you need to, but I find it easy to hold it with a hand), align the print flush with the bottom of the mat board and the right side of the long arm of the T-square. Now the space to measure is between the top of the print and the top of the mat board. Note this number.

Now, you position your print: slide the print up along the long arm of the T-square until the top of the print aligns with half the distance you just measured. (I've marked a half-scale rule on my T-square's long arm, otherwise, divide by two as above).

At this point, your print should be exactly centered and square (providing everything went according to plan). If you wish to have more space at the bottom of the print than the top, simply move the print up along the long arm of the T-square the appropriate amount (I'm creative, every print gets its own position, but matching top border to the sides or just moving a given amount is easy too).

Once the print is in position, place a shot bag on it to hold it in place. I always check the edges and if the print is positioned squarely on the board at this point. Sometimes I have to adjust, but usually the print is properly positioned to within 1/32-inch (yes, I use inches and subtract fractions). At this point, grab your tacking iron and tack two corners of the mounting tissue (if you dry mount, that is, if not, do whatever you need at this point).

Done.

Sorry that the description was so long, but I wanted to be precise and make sure everything was understandable. Describing things like this is a lot more difficult that just showing someone. Maybe I should make a YouTube video :-)

Anyway, I hope this helps,

Doremus Scudder

[Jack Dahlgren]

You might try sticking a center-finding ruler on a parallel rule (mayline). They are easier to deal with than t-squares.

http://www.draftingsteals.com/mayline-armoredge.html

Well, those are certainly more expensive than last time I bought one!

[Renato Tonelli]

Doresmus - thank you for taking the time.

et.al: thank you for the links and PM's.

Late yesterday, a colleague saw this thread and brought me a 'center-finding T-Square'; he practically threw it at me, laughing: "I don't know why you want these things! They're useless!"
I am going to give it a try and if it's not for me, I will go back to my usual method.

Thanks all.