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".
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.
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 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.
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.
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.
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.
Bob,
ReplyDeleteGreat work olmuş.konu was very nice and told us you've photographed.
Send the instrument to address varmı.epos template.
Best regards,
Turgut Onaral
email: turgutonaral@gmail.com
I have watched Matthias Wandel build & use his pantograph & his upgrade but let his math discourage me in trying to build one. You have made building one a lot less intimidating to say the least.
ReplyDeleteI believe that I just may give this a try now that I have viewed your page here. Thanks for posting this online for people to view!
NICE job!
Edward Norton - Indiana
your blog is very nice and very interesting www.aborignaljobcentre.ca
ReplyDeleteGood work
ReplyDeletethank you.
Excelente, muy interesante y bien pensado.
ReplyDeletehi do u know the dimension for scale 2.5?
ReplyDeleteMerci du partage ça me donne envie de le faire merci encore
ReplyDeleteExellent job. Thanks. Could you send me the plans.
ReplyDelete