Make Your Own Engraver ... ALSO known as a Pantograph...3D no less

I watched a fellow wood worker on You Tube.  His name is Matthias Wandel  and he approaches his work with a great deal of mathematical analysis.  He made a jig for cutting "finger joints" that is very impressive.  Then I found his video on making a pantograph.  It looked like something that I might find a use for and enjoy, so I started my search for making my own.

First I did Google "pantograph" and found plenty of references.  Some of those I downloaded and printed for me to study.

I found that the first basic requirement is a parallelogram as the foundation of the unit.  Then you anchor one of the extended ends to the table, the other end holds the "tracer", and the tool is mounted on one side of the parallelogram.  Next, and after a lot of trial and error, I realized that the three points (anchor, tracer, and tool) must be fixed so that they are always in a straight line.  This keeps the finished work from leaning to one side or the other, or being skew.  Finally I began to understand that the measurements for the sides of the parallelogram and the distance from the parallelogram to the anchor and the tracer are the controls for the scale of the finished work compared to the original.

So I decided to play with the measures to get an understanding and to be sure that after I make one, I do not have a list of things I did wrong.  I started with some small pieces of wood and drilled holes at different location.

I even made a pencil holder and mounted it on one side.  This assembly is held together by one inch bolts and nuts.  

I used my logo and traced it to see what my efforts might uncover as problems.

Finally I stopped and went back to precise measures.  I settled on the following diagram:

These measures will give me a 2:1 ratio for engraving.  The master that the tracer will follow must be twice the size of the finished engraving that I want.

So I started cutting my pieces.  I added one inch to the length of each piece so that I had extra space.  Then when I drill holes for the pins that are at the pivot points, the extra inch will give me an extra 1/2 inch between the holes and the end of each piece.  The pieces that I first cut are:

4 - 13" long, 3/4" thick and 1" wide

2 - 7" long, 3/4" thick and 1" wide

1- 10" long, 3/4" thick and 1 5/8" wide

1 - 10" long, 3/4" thick and 2" wide

1 - 4" long, 3/4" thick and 1 1/4" wide

Then I rounded the corners at each end, just to make it look better.

On six pieces ( 4 - 13" long and 2 - 7" long), I drew the center line from end to end, marked the location on each center line for a 3/16" holes, and began to drill.  Each side has a top and a bottom piece.  To insure that the holes are in alignment, I clamped the top and bottom together and drilled the first hole.  Next I put a 3/16" dowel in that hole and then drill the other hole, or holes, as my diagram indicates.

The difficult side to work on has two 10 inch pieces because this is the side that holds the tool.  The center lines have to be moved off center to allow the positioning of the tool. 

The tool is my DREMEL Multi Pro, 2 speed, Model 285 Type 5.  I removed the cap on the base of the tool and measured the diameter of the threaded area, which is 3/4".

Then I drilled a test hole to be sure it would fit.

I marked with my awl an off center line end to end on a thin piece of metal 3" x 1 1/4" and another perpendicular at the center, then drilled a 3/4" hole, which the tool will fit through, and 4 - 1/8" holes for screws.

Next I had to position a 1 1/4" hole on the bottom 10" piece that is 1 5/8" wide.  This will generate an over size border that will allow me to slightly adjust the positioning of the metal piece that is screwed to that bottom and allow room for the cap to be screwed back on the threaded area.

Once the tool is inserted and the cap screwed back on, it will guarantee that the tool will not slip and possibly change the depth of the cut.  The lines drawn from end to end and the lines perpendicular to that are the guides for the placement of the metal piece that also has lines indicating the center of the hole.

These lines will give you references for alignment.

I turned the bottom over and realized that I will need to remove some wood so my fingers can gain access to the collet when changing bits, as well as being able to screw the cap on or off with my fingers.

I used a rasping type bit in my drill press and carefully removed enough that gave me space.

Next I designed the top of this part.  I marked a line end to end and then a perpendicular for the center of my 3 holes.   I placed the 4" piece beside the larger one as it will be when finished so I could position the larger tool hole.

  I used a 2" hole saw to remove the area needed to secure the DREMEL.

Then I trimmed the circle so that it is a "U" and glued some strips of cork to line the inside.

I marked the 4" piece,

cut that arc away, and added cork there also.

After making sure that the tool fits into this holding area, I clamped the two pieces together and drilled holes for two 1/8" bolts that will have "wing" nuts on them and hold the two pieces together.

Now I start to make the "spacers" that will be between the top and bottom of each side.   To insure balance I marked the center of the edges on the spacers and when joining these together,

 I aligned this mark with each line on bottom and top that goes end to end.

I started with the tool assembly side first by attaching the top and bottom piece to the tool.  This gave me the chance to position the top piece to the best possible place for grasping the tool and not interfere with the "off/on speed switch".  It turned out to be about  2 1/2" for the measure needed between the top and bottom.  I cut two pieces that wide from a 1 x 4 and cut the length to fit within the area allowed.  Next I glued the spacers and clamped them to the bottom, then when the glue was set, I added two screws in each into predrilled holes .

I put a 3/16" wooden dowel through the holes in both ends of the bottom and added the top so that the dowels keep the top and bottom in alignment.  Repeated the process of glue, drill, and screw to add the top to this assembly.

I realized that the parallelogram will be in constant motion while in use, so I used 3/16" dowels and assembled the entire unit without any spacers other than those on the tool side.  Next  I moved the unit to each extreme position that it would have to accommodate and with my pencil I marked the areas on each of the bottoms that must be free of obstruction for the unit to operate correctly.

Then I cut some card stock in those shapes and punched holes for locating the screws.

I cut the spacers  2 1/2" wide and 4" wide and placed the card stock on top of one end.  This showed me how each of the spacers had to be shaped before I put the pieces together.

Once each spacer was cut and shaped, I glued and clamped each to the bottom.  After about an hour I removed the clamp and used the card stock to mark the location for predrilled holes for two screws into each spacer through the bottom.  Then I put a dowel through the holes at the ends of the bottom and added the top.  Repeated the process of glue, drill, and screw to add the top to each of the remaining sides.
 

Next I cut the 5 pivot pins from a long piece of 3/16" metal rod.  On one end I heated and flattened for a top and slightly tapered the bottom to help guide when inserting.

Finally the pantograph is assembled.

I moved it to all extremes and checked that the spacers are not prohibiting movement.

Since this is a 3D pantograph, I need to attach it to a 1 x 4 board using a hinge.  This is another pivot point.  From a 1 x 4, I cut a 4" piece and a 1 1/2" piece.  For this unit the  1 1/2" piece is 4" long so it will fit between the top and bottom of the anchor end.  I cut a rabbet  3/4" wide and about  1/4" deep down the middle of the 4" piece.  Then I rounded one edge of the 1 1/2" piece, drilled a 3/16" hole, and glued and screwed it into the rabbet.

I left a 3/4" space at the bottom because this will allow the pantograph to slide a top and bottom over this piece and a pin to go through.

To attach the mounting piece to the base board I used a section of piano hinge that I cut from a long one.

When I first tried to use the unit, I realized that it must be elevated because of the thickness of the wood that I will be engraving.  I cut two pieces to that thickness and placed them under the base board.

I cut another piece of 1" wide about 8" long, drilled a hole in the center, and added it to the end where the tracer is located.

I hold the ends of this piece in each of my hands and this is like a steering board.  It helps me to make a smooth and continuous movement while engraving. 

I added some pieces to keep the steering board from slipping up the tracer.

For my test run I clamped the unit to my TABLE TOP (PORTABLE) WORKBENCH (one of my other blogs in this set), placed the dogs in position and opened the bench vice.  By adding strips of wood I was able to place a strip horizontally against the dogs, then the work piece, then another horizontal strip of wood, then two strips perpendicular to that strip and butted to the bench vice so there is a space between the two for the master that I will copy.  Then I tighten the bench vice and secure this assembly so it will not move.

Now I found a new and difficult problem.  I must move the pantograph so that the bit in the DREMEL scans the area where I want to engrave.  At the same time I must watch the tracer so that I am able to position the master design that the tracer will be following.

At first I used trial and error, but finally I realized that I need to cut a rectangle out of paper that is twice the length and width of the area that is to be engraved.

Then I put the bit in the top right corner of the engraving area, and I slide the rectangle so that the tracer is in the top right corner of the rectangle.  Next I do the same for the bottom left corners.  Now the master is placed inside the rectangle and positioned for proper spacing.

Tape it down and engrave.

The bit I finally found to be the best is a diamond coated one with a very, very small tip.  I got this bit off eBay with a set of about 12 or so.

This one works best for what I want to do with the pantograph.

I also wanted to test the 3D application of this unit, so I used a three dimensional piece and a block of soft red wood ... and after some effort....

I found that sometimes I do want to adjust the depth of the bit, so I made a small piece of 1 x 4 that allows me to raise the unit and rest it while I make adjustments.

Finally the unit will rest and be out of the way when not needed because of the hinge on the back.

I hope this will help you to be encouraged to make one for your own use.  Remember that you can control the size ratio by adjusting the measures and placement of the pins that are the pivot points for where the sides come together.  You might want your engraver to be larger or smaller.  Do a lot of searches and test before you settle on your design so your efforts will produce an engraver that is just what you want.

Thanks for looking and good luck.

What a ... BENCH ! ! !

Recycle throw-a-ways to be collectibles...

Many times when a person is building something from wood, there will be 'end cuts' or left over weird shapes of plywood.  I try to never throw these pieces away.  At the very least size or utility, I use the final item for kindling through the winter in my wood stove that helps to heat my house.   So no matter where I find or get a piece of wood, when it leaves me it will be ashes.

Note the example below:

Here I have an end cut from a 2x4 with nail holes, obvious age, and structural damage.  Also this is a piece of California Red Wood.  I take this piece to my table saw to slice it into pieces kind of like bacon.

I have a slide block I made from another 2x4 end cut with a black piece on the back that sticks out just enough to catch the work piece and push it forward.  I set the fence with the push block adjacent so that there is about 3/16 " or a tad more distance between the blade and the push block.  Next I hold the work piece beside the push block and slide it into the blade, again, again, and so on. 

With the resulting slices, like bacon, I reset the fence with the push block so I can cut these slices into long pieces that are about 1/2" wide.  Being very careful, I am able to get 3 thin pieces from each.  The result is pieces that are about 3/16" thick and 1/2" wide.

Next I find another end cut just made to be the support pieces for the bench.

I have drawn my diagram, scanned it into my computer, print a copy, cut it out, and with clear tape, I attach it to the block.  Next I take this to my band saw and cut away the area that is not needed.  Using a belt sander, I sand one face of the piece to be smooth and unmarked.  I continue the sanding on this piece until the lateral sides are smooth and none of the saw blade marks from the band saw are noticeable.   At this point the piece is ready to be sliced into profile pieces on the band saw.  

I use a vertical fence set about 5/64" from the blade and present the piece lying on the back with the top feeding first.  After each slice, I take time to sand the fresh face on the belt sander.  This will reduce the sanding after you finish all slices and help maintain a uniform thickness.

Now I have all the needed pieces for the assembly of the bench and the supports are all identical.  These must be sanded to a fine finish before any assemble can happen.  Once it is glued together you will regret not sanding first.  I'm not crazy about the sanding, but since this is all Red Wood, the total time is very much less than if it was Oak.

Once all is sanded, I select the two end supports

 and clamp each one to an Oak block I have left over from some other project.  Using my "TABLE TOP (PORTABLE) WORKBENCH" (one of my other blogs on this site), I set two dogs in proper holes and put a strip of wood as a back brace.  I slide the Oak block to touch the back brace and then the bench support slides back adjacent to the block to touch also.  Now I clamp the block and the support together.  I do the same for the other block and support but I put the block on the other side.  The block will insure that the supports are vertical, not leaning, and the block also gives the added feature of making the support perpendicular to the back brace.  As the seat slats are added, I now know they will be perpendicular to the two supports and the supports are parallel to each other.

Here is when the TABLE TOP (PORTABLE) WORKBENCH  really shines.

The dogs are the black metal squares peeking over the back side of the brace.  The supports are attached to the blocks and butted back to the brace.  Finally a piece of board is butted to the front of the blocks and this allows the 2" thick face of the bench vice to apply pressure to the grouping.

I always put the first seat slat in position and slide the two end pieces slightly left or right to insure the 'over hang' at each end is equal before I tighten the bench vice.

I use my gauge that is preset to check both sides for the overhang.  Now I snug the bench vice on my TABLE TOP (PORTABLE) WORKBENCH  so that it will hold all in place.  All is now stable and ready.


The seat has 4 of the slats and the other two are the back slats.  Place all 4 seat slats in place and adjust until they have equal space between each.  Remove the two in the center, then pick the back slat up so you can add glue to the horizontal edge of the support where it was resting.  Gently replace that slat, check the overhang, and hold it there for a few seconds.  Next do the same for the front slat.

After holding it for a few seconds, I get another piece of 2x4 and gently place it on the two slats for a little pressure while the glue sets.  This is usually about 30 minutes.

After a time and before I glue the middle two slats,

I use a short piece of 2x4 to butt it to the two slats already glued.  Clamping this in place will give me the perfect straight line for the ends of all 4 seat slats.  Now I glue the middle two slats, just as before.  At this point I let the assembly set for another 30 minutes before I continue and handle the assembly.

From one of the end supports, I get the Oak block and the clamp.  I use these to get the center support ready to be added to the assembly.

Set this piece beside one of the end supports and make dots with a pencil in positions where you want to put the glue.

Set the assembly aside, add glue to the center support, and place the support in the middle of the assembly area.

Next I put my ruler on the seat slats so that I could locate the center, here it is 7 1/2 inches.  This is the target for the center support.  Carefully set the assembly over the center support and slowly lower it so that when it makes contact with the center support, it will be located correctly.

I take one of my old sanding pads with soft sponge on the back, place the sponge on top of the seat slats, add the 2x4 so there is a flat surface for equal pressure, and set my 8 pound small anvil on top.  This will insure that all 4 seat slats will have good contact and pressure for the glue to harden.  At this point I will let the assembly have at least an hour or two before I continue.

Now I have two slats to glue for the back rest.

Turn the assembly around and rest it on the back.  The rear legs should be butted to the back brace and the seat slats butted to the 2x4 so the new slats will be in alignment.  Make sure where these slats are to be located, then start with the slat closest to the seat.  This is because the when you look at the finished project, you will visually see the results of the seat and the first back slat.  If these are not parallel you will be very disappointed.  Also you will not be boxed in by the other back slat.  Glue and clamp the slat, then let it set for another  30 minutes.  Finally you are ready for the last slat to be added to the back in the same manner.

When I am positioning the slats and finally ready to glue them to the supports, I find a small piece of discarded wood that is just the right thickness, or width, to use for a guide.  This is almost like having a third hand because with alignment, glue, and wanting it to be right ... if I had to also hold a ruler in order to place each piece in the right position then I could easily make a mistake.  Also this will keep me from having to make pencil marks and then later having to sand away those marks.

Here you see the three pieces I used as reference guides while assembling the bench.  These are pieces that I found in my waste bucket that is used to collect pieces that will become kindling ... and they get one last use before they help start a fire.

Final step is two coats of a water base polyurethane.

From an old unwanted discarded piece of 2x4 ...

to a beautiful miniature bench for a child's doll house or a collector.

I also sell such items on eBay under the seller name "stirlingbay".   This all started when I discovered an artist named Diana Manning and her "Family of Friends" shelf sitters.

I feel that these guys, which I really relate to, need a fine bench or chair to set on rather than the edge of a shelf, where they might get knocked off and damaged.

Thanks for looking....