making drawings that are symmetrical on both sides of a centerline

[Guy Lautard]

I have a copy of the book The Art of Engraving, published by "THE KEYSTONE, the organ of the Jewelry and Optical Trades," and possibly written by B. Thorpe, circa 1903.

I was looking at it the other night, and out fell a small leaflet (an ad) for some engraver's aids, one of which was called "The Engraver's Companion," mostly to do with transferring designs to workpieces. On the back page of this leaflet were illustrated a duplex tracer (hard vulcanized rubber point at one end, a steel point at the other), and a "Self-Dividing Straightedge," said to divide any space into 4 or 8 equal parts without spacing off with dividers. If anyone has one of these old Self-Dividing Straightedges, I'd be very interested to know more about it.

The info about the Engravers' Companion might be of interest to Forum members. If so, I can post it.

Buried in the info in the above advertising leaflet was an idea which I tried, and that worked out well for me.....

I find it difficult to draw something that is symmetrical on both sides of a centerline, if the drawing is basically a free-hand one. Likely others do also.

The idea I found in the Engravers' Companion leaflet was as follows (stated in my words):

Fold a sheet of paper in half, then unfold it again, and draw in a centerline (in pencil) where the fold is.

Then, draw what you want to have on one side of the centerline, fold the paper again, and burnish over the area where your drawing lines are, very hard, with a burnishing tool* of some sort.

When you unfold the paper, the lines you drew will have transferred enough graphite to the paper on the other side of the centerline to give you a good image there.

You can go over that half of the drawing with the pencil to darken the lines, and you will have a symmetrical drawing of what you want. It will be excellent, if not perfect.

Kids in kindergarten probably do the same thing (possibly with a CAD program), and think it is routine business.

* (For a burnisher, I use a steel ball on a handle. I made this device some years ago for a different purpose. I wish I could tell you that it is a Palm Controlled burnisher, the best item of its type made anywhere (not yet even being crudely copied by any other engraving equipment maker anywhere!); that there is some secret to making it, or the shape, or the material from which it is made, which only I know; that I make them for sale at $298 each, and that without this item your results will be such that you would have been better to stay in bed, but none of that would be the case.)

Guy

[NevadaBlue]

Thanks for that! Wow, another celebrity in our midst! Welcome to the forums, I've been a fan of yours for years.

[SVD]

Ron Smith has mentioned a similar technique but he uses tracing paper - that way you can just fold it over and see the lines on the other half.

[Guy Lautard]

NevadaBlue:
Thanks for the welcome and implied kudo. The idea of being a "celebrity" just purely makes me cringe - I'm just me, and as simple as a pail of mud. I feel fortunate to have met a large number of very nice people though my books etc.

SVD:
Tracing paper? What will they think of next? ;-)
I suppose that would work, but rubbing a folded picece of paper to get what you want is more fun. (I know - rubbin' a piece of paper is not how to get a genie to jump out and grant you 3 wishes.)

Guy

[bobkeyes]

Dear Guy,

I for one would love to see the brochure on the engravers companion. Thanks a lot for the info, especially on the burnisher.

[Guy Lautard]

Ok - I am going to try to upload 3 pictures (scans) of that Engravers' Companion advert. The ad is old, and I don't know what types of material it may have contained. Maybe some of the experts on here can tell us. Bob Steffens, boss of the Cronite Corporatin once told me that the red wax on (some?) Gouda cheese makes a pretty good transfer wax.

And just for fun, can anybody guess how that "blueprint" look came about?

Guy

[jlseymour]

Thanks for the info Guy, and welcome to the forum...
Jerry

[weldon47]

Good stuff!

Thanks, Guy
Weldon

[Eric Watson]

Good to hear from you Guy. I certaily enjoy your Readers.

[bobkeyes]

Thanks a lot Guy for the brochure. It looks, "Vellee intaesting"

[Francis Kisner]

I was trying to see how the Self-Dividing Straightedge might work. This led me to try a search on the net which led me to US Patent 6243963 - Dividing rule. http://www.patentstorm.us/patents/62...scription.html
Probably not at all related to the self-dividing straightedge but an interesting device if one had to divide a space into equal sectors.

Anyone else have any idea how a self-dividing straightedge works? Is it just a straightedge with equal graduations from the center?

Francis

[Guy Lautard]

Hi guys,

Thanks for the friendly welcome and comments.

Guy