Adjustable Pantograph

A pantograph is a mechanical tool that can be used to reproduce an enlargement or reduction of image. It uses a linkage armature that moves a pen or pencil and draws a copy as a stylus is traced over the original image. This is old technology that has been around forever and it’s a lot of fun to play around with.

This is a pantograph I made a number of years ago. I haven’t used it very much. I had originally intended it to help reduce and transfer sketches onto small cards for use as artist trading cards. Like many of many of my projects, once I completed the tool I moved on. Most of it was turned on a machinist lathe, then the rest was done on a mill.

In the photos I am reproducing an image of a bank vault locking mechanism. The resulting drawing is about 1/3 the size of the original. I can adjust the ratio of the transfer by moving a few of the pivot points on the 1/8″ rods. Each pivot has two knobs, one for each set of arms of the pivot point. The white disk washer on each pivot is made of Teflon to act as a bearing surface. The action of the movement is very smooth, which is important in creating a small drawing. The stylus is just a pointer and the drawing arm can hold a pen or pencil. I’ve considered trying to mount a small pneumatic pencil engraver in the place of the pencil. With an engraver in place, the pantograph could be used to carve stamps or printing blocks. The vibration and torque from the engraving bit might require a sturdier armature.

I mounted the armature on a one foot square of 1/4″ clear acrylic. That makes it possible to copy from thick or bulky original by just placing the pantograph on top of the original and tracing it through the acrylic. What I really need is a case to hold this thing in. It can be difficult to transport around without the worry of damaging it.

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Desktop Homesteading

My endeavor to build a miniature log cabin has continued this lunch hour. I gathered some more alder twigs, pealed the bark, and then microwaved them for two minutes to dry them out. I’m using a small Post-It notepad as a template for the long and short lengths of the log rounds. I cut six long and six short ones and cleaned up the ends with fine sandpaper. I had to clip off a few small knots with wire cutters and then sanded them to smooth the cut surface out.

I notched out each log as I glued them up. This is a process that takes some patience and a lot of fit checks. A small dab of glue is all it takes and then hold the log down with tape until it dries. I’ll probably use some air-dry clay to make the foundation. I might even fit the whole thing inside the miniature “steampunk” terrarium I made a while ago. The scale is just right for it to fit with some clearance.

Micro Mill from Scratch

It was a long time in the making, but I have finally finished putting together the micro mill that I started about five years ago. It was one of those projects I started, got 95% complete, then moved on without doing the finishing touches. I made it out of scrap aluminum, some 4-40 and 1/4-20 threaded rod, 1/8″ drill rod, some pieces of Teflon and Delrin, and various screws and bolts. It was all machined on a Bridgeport mill and a lathe. The motor and chuck I salvaged from a 12 volt carving tool. It’s an import with non-standard collets, but it works fine. I made a new housing for it out of aluminum to make it easier to mount on the mill.

The base is a simple X-Y table with 4″ of travel on X and 1 1/2″ travel on Y using 4-40 lead screws. It isn’t robust enough to mill anything more than wood. The table has three T-slots milled in it to accommodate #6 nuts and screws. Right now I have a piece of 1/4″ MDF screwed to the top and will use double stick tape to hold the small pieces of wood for milling. I will only be making light cuts and the tape will hold just fine.

The top of the mill has a lead screw of 1/4-20 threaded rod with a knob for adjusting the mill height. I can loosen the motor with the red knobs to reposition it also. The mount for the motor is spring-loaded, so if I want to do plunge drilling or use a bur to make the pips on a couple dice, all I have to do is loosen a knob in the back to release the motor mount from the lead screw.
I will probably make an arm for plunging the drill and reinforce the mounting of the upper part of the mill to the base. I’ve made a few cuts on it so far and it will be nice to use it for making some miniatures.

Miniature Log Cabin Construction

This has been rolling around in the back of my mind for a while. A long time ago when I was a kid, I worked on a group project for school that involved building a model of a Lewis and Clark fort, Fort Clatsop. The model was made out of sticks, log cabin style, using a “rat tail” file to cut the notches in the logs for fitting together. The file was about 3/8″ round, roughly the same diameter as the sticks. It worked quite well and the finished fort was a fairly convincing reconstruction.
My idea has been to do that again but on a smaller scale using 1/8″ diameter sticks and a round needle file to match. I clipped a couple of twigs from an alder tree, peeled the bark, cut a few to length and microwaved them to dry them out. Four “logs” dried out in about one minute on high. They peel easily when green and file without splintering when dry. Two sticks were cut to 1″ and the other two to about 1 1/2″ with a fine tooth X-Acto saw blade. Notching is easy, just make sure the notches are on the same side. These four sticks give a footprint roughly the size of the smallest size Post-It note pad.

I’m thinking it might be fun to build a little cabin on a foundation of tiny stones, glued together, and roof it with cedar shingles about 1/4″x1/8″x1/32″. The shingles would be “riven” with a chisel from a scrap of cedar. The log rounds would be glued as they go up.
I’m still working on my other projects, but this one is easy to throw in.

DIY Mini Rocket

This is a mini rocket that you can build with a book of matches, some aluminum foil, a paper clip, and a sewing pin. I saw this in a book, “The Great International Paper Airplane Book” when I was a kid. I don’t claim credit for this clever rocket, but I did almost set a girl’s prom dress on fire in a restaurant when I was a teen.

First part is to wrap half of the match in foil. It takes a piece about 1/2″x1″ in size. Try to fold it neatly and not just crumple it around. If you use too much the rocket won’t lift. Too little and it will burn through the foil.

Push the pin up to the head of the match along its side. Don’t push it through the end of the foil. This will be the jet.

Bend a paper clip open enough to support the mini rocket. Put it in position and aim it in a safe direction. Light a match and hold it under the foil covered tip. A second or two and the rocket should shoot off. It takes a couple of tries to get it right. Happy Fourth of July! Use extreme caution when trying this- adults only.