There are few things in this work-a-day world that bring as much joy as a
relaxing hobby or pastime.
I have chosen to honor mine with a wall plaque lettered "Let's Get Plastered." I know what you're thinking. " Boy, those are truly words to live by !" and if you enjoy getting plastered as much as I do, you go ahead and use that saying. Or you can use anything from "God Bless This Mess" to "The Devil Made Me Do It". It doesn't matter what the saying is, the process for creating a plaster wall plaque is the same.
I've decided to make my plaster plaque with raised lettering on it. That means it will
be harder to do than one with carved in lettering. Sure one with incised lettering could
be done in half the time., but think about the perceived value. That means that yer
friends will say "by jiggety Zeke, how'd U do that? That'n looks dern near
like a store bought'n wall plack!"
And of course your reply will be "oh yes, I have given this wall plaque greater
perceived value with raised lettering. Other factors such as weight, color, smoothness and
coolness are also contributors to a higher perceived value in the mind of the
consumer."
You may be met with a blank stare as if you had announced "I have just stepped off a flying saucer and have been probed by aliens."
Have no fear, you may recover your dignity by saying "Hey friend, I think what you need to do is give this perceived value thing a thorough testing by wrapping your fingers around a few tall, cold, smooth, heavy glasses of aged lager.
See! problem solved. Now let's get plastered.
You will need:
On one of the pieces of typing paper lay out the lettering of your saying with the lead pencil. Two of the styles I considered are at the left. Make sure the letters are the exact thickness and style that you want them to be on the finished plaque .
Your plaster bat is about 9" x 12", so be sure to keep your
lettering at least 1/2" from the edge of the plaster bat. Place the piece of paper on
the bat to check the distance the lettering is from the edge.
Congratulations! You are now a high powered graphic art designer. As everyone knows, any high class graphic design studio worth its ink has an expensive contraption, called a lightbox, which lets the light shine through the paper so they can trace drawings.
We, of course, will hold our drawing up to the window, being the true cheapskates that we are, to let the Good Lord's free sunlight do the job of a lightbox for us.
When you put your graphic design up to the window, place the side with the drawing on it against the glass. The writing will now show through reversed. Very carefully trace over the backwards lettering with you pencil. It will appear perfectly normal, if you are from that Star Trek alternative universe where everything is opposite of ours.
Take the drawing down and go over the lettering on both sides of the paper with a Sharpie Felt Tip Marking Pen. Confused yet ? keep reading it gets worse.
Dampen the plaster bat. Place the graphic drawing on the bat so that it reads backwards once again as you are looking at it.
With a ballpoint pen or hard lead pencil, trace over the lines of the drawing. Press hard enough to make marks indented into the plaster beneath the paper. Do not shift or wrinkle the paper as you trace over it. You can put thumbtacks or push-pins over the paper to hold it in place. You can not use tape to hold the paper in place. It is a hard, cruel fact of life that tape will not stick to raw plaster.
Some of the ink and pencil lines will be transferred to the plaster bat and there should be a slight groove where the ballpoint pen has pressed into the plaster.
If you do not see the lines, you did not press hard enough, your plaster was
too dry or you need another pair of cheaters from the dime store (I think they're dollar
stores now).
Dampen the plaster bat if it has dried out.Go over the lines on the plaster with an indelible blue pencil, available at art stores for copy work. A dark blue drawing pencil may work instead.
Your plaster bat should now look like this.
You are now ready to carve the lettering
Finally! Praise the Lord and pass the ammunition!
To carve out the letters you will need a tool to cut grooves. For our purposes of discussion we will call it a grooving tool. You can buy a set of tools for carving plaster or you can make one from a 6" to 8" length of steel rod 1/8 to 1/4 inch thick. Several different sizes sure would be handy. For information on making this tool, click on Dan's Tool Works!
Now that your lines on the plaster bat have been darkened with the blue pencil you can start groovin' with your new tool.
Make long sweeping cuts at first to establish the basic shape of the letters. Short choppy strokes will create chatter marks and make lumpy looking letters. Groove out all the letters on the entire plaque scooping out material between the lines.
Do not create undercuts as you carve.
Work slowly and deliberately; hold the tool firmly. You're a model maker now. You know
exactly what you are doing. Right? (Okay, just fake it).
You should be cutting out about 1/16" of material with each cut.
Patience and control are as much a part of the training as are the technical processes.
You may not do a perfect job the first time. It's exacting work and it takes time to develop the skills.
Don't worry if it's not perfect. Enjoy the process. There's a kind of rhythm or timing to it. If you rush it you will mess up. If you go to slow you are out of sync with the universe. All is right with the world when you find your pace. Every cut or action is as it should be. An economy of movement sets in and you won't be struggling.
Continue until all the plaster is removed from all the outlined letters to a depth of 1/8 to 1/4 inch. That will make a nice high letter when we pour the plaster model. What we are making now would properly be called a negative since we will be pouring plaster into it to create a positive.
After the rough carving is done use very light strokes to clean out the letters.
Now that all the letters have been grooved out
lightly sand the entire mold.Go over the carved out letters with sanding pads or fine sand
paper . Slightly round over any sharp edges. Sharp edges around the letters will
make the model stick when you go to remove the model from the mold. That
should finish up the refining of the negative or mold for your
plaque.
Time to get Positive
Now that You've carved out such a beautiful little negative mold with nice smooth incised lettering all in reverse, we'll have to pour plaster into it to create a positive with raised lettering.
You will need :
Thin your shellac with an equal part of alcohol. Mix well. Take your plaster
mold in hand and give in a good shellacking. I'm not talking about the kind of shellacking
mama used to apply to my backside with a hickory switch, for hiding behind the arborvitae
bush from the big yellow school bus,but a tender gentle shellacking, applied carefully
with an inexpensive paint brush. Use your 50/50 shellac/alcohol mix to liberally coat the
mold.
Let the mold dry for 15 minutes to 1/2 an hour. Then soap up the mold twice. Follow directions for soaping up in episode 3.
Putting Mold Boards around your plaster model
Set the boards on edge (thin side down on your table wide side against the mold.) Construct a closed in form around the plaster bat to contain the plaster mix.
There are several ways to hold boards in place to create a form for pouring plaster .
One way is with pipe clamps. 
| Another is with mold straps. |
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You can use c clamps.
To use C clamps I attach a piece of wood 1 1/4" square to the edge of my mold board with screws, indicated by red arrow above.This will give you a place to clamp two boards together, as shown in the photo to the left.This system works best on large molds as pictured.
Another way to hold boards in place is with a piece of waxed cord. This system works best with very small boards. Take a length of heavy cord ( 2 to 3 feet long should be about right) and rub it well with bee's wax. This will keep it from loosening up after you wrap it around the boards.
Now that you have properly shellacked and soaped the mold and boards and have put the boards around the mold, we can go ahead with complete confidence and pour plaster on the mold.
Mix up
a batch of pottery plaster or molding plaster. Remember to mix a little more than you
think you will need. See Episode III, Mixing & Pouring Plaster. Pour the mold to a
depth of 1/2" to 3/4". Wait 30 minutes or longer. Remove the boards from around
the edge of your mold.
Stand the mold and casting up.If they do not separate easily on their own insert a knife blade between the two and they should come right apart.
If you have carved the lettering without making undercuts and have properly sealed and soaped the mold, you will be looking at a perfect casting.
If you break your model while removing it from the mold, you can glue it
back together with Duco Cement, or soap the mold again and pour another model. This time
look for where the model is hanging up in the mold and remove the undercuts. If you break
the mold while removing the model your life is pretty much over at this point and
you should not consider going into mold and model making in any serious manner. Just
kidding ! Just kidding ! I break them all the time and I've been doing this
since before Moses parted the Red Sea. Glue it back together.
Some people add a little Hydrostone to their plaster mix to give it more strength They feel that the addition of hydrostone will make the model carve more smoothly .The addition of hydrostone will make the model very hard though.So be prepared to put a little more effort into the carving if you use it. I use a straight pottery plaster or molding plaster mix.
Clean up the model with sanding pads or sand paper. Go over all the raised letters especially around the edges.
Now you can give your plaque a unique shape around the border if you wish. I have given
my plaque an interesting shape by contouring it with my mold knife. The next step
will be to taper the edges of the plaque on an angle. This is called putting a draft on
the model. I use a steel scraper that has been ground to the angle that I want the edge of
the plaque to be (as shown in the photo below).
Place
your plaque on your marble with your lettering facing up. Scrape the edge of the plaque
with your steel scraper all the way around to give it the proper draft. You need at least
1/16" draft. That makes the plaque 1/8" wider on the backside than the front.
Since there is a 1/16" draft on either side.
I told you it would get more confusing as you went on.
That about wraps up the making of the model.
The Finished plaque model is shown below:
If we ever want to make any money at this, we're going to
have to make a rubber mold of our plaque so we can mass produce them.
Then we'll be movin' on up.....to that deluxe apartment in the sky!
We'll tackle rubber mold making next time. For now I think we deserve some credit for a job well done.
In fact we did so well, I know just what we should do ...
send responses to: dandoesit4@plastermaster.com
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