Below are links to short articles in the series “A Brief History of Painting Frames” by John O’Keefe Jr. Each article includes reference images and diagrams to help you identify frame design features unique to each historical period. New links will be activated as additional articles and relevant materials are added. Please enjoy.
This 16×20 canvas stretching tutorial focuses on a giclee print on canvas. However, the steps can also be applied to any medium-sized canvas, whether raw, primed, or painted. I provide tutorials like this for free because I feel that all of us should be able to enjoy creating art without all the “extra costs” that many would charge for this level of information.
16×20 CANVAS STRETCHING – MATERIALS AND TOOLS
Before starting, Assemble all materials and tools for the 16×20 canvas stretching tutorial.
Cloth Work Surface
Giclee Print (not shown)
Pre-Made Stretcher Bars
CANVAS STRETCHING – APPLY GLUE TO STRETCHER BARS
NOTE: (Steps 2 through 4 are optional)
We will use Elmer’s Wood Glue to bond the stretcher bars ends together. Because we are using pre-made stretcher bars that come ready to assemble, we may need to sand rough edges that have resulted from the cutting tools used during the manufacturing process.
Apply a small amount of glue to each end, as shown. Repeat this for each stretcher bar before continuing to the next step.
Using your finger, spread the glue around each cut end’s surface, as shown. Repeat this for the remaining stretcher bars.
CANVAS STRETCHING – ASSEMBLE THE STRETCHER BARS
Begin mating the stretcher bars.
Make sure that you fully seat the stretcher bar ends. If you see a gap along the seam where the ends meet, you have not fully mated the two bars.
In this view, all four stretcher bars are shown mated together. However, we must ensure that all four corners of this assembly are square before the glue sets. (i.e., A, B, C, & D)
If you used glue (as shown in steps 2 through 4), wipe off any excess glue that has squeezed out while mating the stretcher bars.
Measure the distance between corner A and corner B.
Measure the distance between corner C and corner D.
Compare the two distances against each other. If the distances AB and CD are equal, you are square. If they are not equal, you are not square.
(In our example, distance AB was 0.125 inches larger than distance CD, and we need to make adjustments as shown in steps 11 and 12.)
While firmly holding the stretcher bar assembly, tap the corner with a mallet with the largest measurement.
(In our example, we will tap corner A.)
Recheck all corners to make sure they are square. We can use the earlier tape measure or square ruler method shown here.
Hold the square ruler as shown and check that both inside edges of the ruler run flush along the surface of each stretcher bar. You are not square if the ruler lifts off on one side (not running flush along the entire surface). Repeat this check on all the remaining corners. If your stretcher bar assembly is square, you are ready to start the canvas mounting process.
Using light-grade sandpaper, gently remove any rough or broken wood from corners.
Ensure the corners are thoroughly sanded, and no rough edges remain.
CANVAS STRETCHING – PREPARE FOR STAPLING
Before laying down your giclee canvas print, make sure there are no debris or wood pieces (that may have fallen off during stretcher bar assembly) that could damage the printed surface. A soft cloth work surface minimizes the chances of causing minor scratches to your giclee canvas print.
Lay down your print (face up) and make a final close examination to ensure it has no damage.
Turn over your giclee print at this point, so the image is face down. You are now ready to position your stretcher bar assembly.
Place your stretcher bar assembly over your giclee canvas print as shown.
16×20 CANVAS STRETCHING – STRETCHING AND INSTALLING FIRST STAPLES
Starting with the right side, carefully lift the canvas print and ensure the image is wrapped around the front face of the stretcher bar. Repeat this on the opposite side, moving the stretcher assembly left or right until you see the image wrapping equally around both sidebars.
Once you are sure that you have centered the stretcher bar about the printed image, draw a reference line along each side as shown. This reference line will be helpful later if the stretcher assembly moves out of position and you need to realign it.
As we did in Step 18 for the side positioning, we want to center the stretcher bar assembly along the top and bottom bars. Carefully lift the canvas print and ensure the image is wrapped around the front face of the bottom stretcher bar. Repeat this for the top stretcher bar, moving the stretcher assembly up or down as needed until you see the image wrapping equally around the top and bottom bars.
Once you are sure that you have centered the stretcher bar about the printed image, draw a reference line along each side as shown. We have now centered the stretcher bar assembly in both the vertical and horizontal directions concerning the printed image. We are ready to begin the canvas stretching, wrapping, and stapling processes.
16×20 CANVAS STRETCHING – STRETCHING AND INSTALLING FIRST STAPLES
For this example, we have selected 1/4″ staples. Load your staple gun, so you stay supplied with staples partway through the following steps.
Starting with the top stretcher bar, wrap the giclee canvas print around the stretcher bar as shown. Ensure the stretcher assembly has not moved out of the reference lines we drew earlier.
Holding the staple gun squarely on the canvas and stretcher bar, staple the canvas to the stretcher bar in the center of the bar as shown.
Check that your assembly looks like this – having one staple in the center of the top stretcher bar.
While firmly holding the canvas pliers, grip the canvas in the center of the bottom stretcher bar, opposite from the first staple in the center of the top stretcher bar.
Using the stretcher bar as leverage, rock the canvas pliers forward (compare images from steps 25 and 26) until the canvas has stretched – notice that the canvas is tightly wrapped around the stretcher bar.
Before releasing the canvas pliers, press your thumb onto the canvas. Holding your thumb in this manner will maintain canvas tension during staple insertion.
While firmly pressing your thumb on the canvas, insert one staple while maintaining tension. Hold the staple gun squarely on the canvas and stretcher bar and staple the canvas to the stretcher bar in the center of the bar as shown.
Check that your assembly looks like this – having one staple in the center of the bottom stretcher bar.
Once you have inserted the first two staples into the top and bottom stretcher bars as shown you should notice a slight tension pull on the canvas between the two staple points (i.e., points A and B.)
Using the canvas pliers, stretch the canvas starting on the left side and hold tension, applying firm finger pressure. (…I am keeping the pliers away from my body, and this provides less stretching and leveraging control. Because I’m not applying tension for the first side staple, I chose to use the pliers this way. However, when you are stretching opposing sides it is recommended to hold the pliers so that they are facing toward your body as shown in images 25 through 28)
Insert one staple in the center of the side stretcher bar.
Repeat the stretching and stapling process as shown in steps 25 through 28. Be sure to firmly hold the canvas with your thumb before removing the pliers.
Be sure to stretch the canvas when stapling opposing sides, so it does not droop or sag. Our assembly should now have one staple placed directly in the center of each stretcher bar, as shown.
Flip over the assembly to look at the printed image on the front. Check that the image is centered vertically and horizontally – you should see the image wrapping equally around all sides, and no ‘white’ border should be visible along the front face. Check that the image has not rotated clockwise or counter-clockwise so that it is no longer square with the stretcher bars. Also, check that the canvas is not overly loose or sagging. In the following steps, we will tighten the canvas as we stretch, wrap, and insert the remaining staples, but now is the time to remove the staples and make adjustments if the position of the image is off or the canvas is very loose and sagging.
16×20 CANVAS STRETCHING – STRETCHING AND INSTALLING REMAINING STAPLES
Beginning with the top stretcher bar (1), stretch the canvas using canvas pliers and hold tension by applying pressure with your thumb.
Insert staples starting from the center staple and moving left with each new staple until you reach the left stretcher bar, as shown. Use canvas pliers as needed.
Moving to the bottom stretcher bar (2), stretch the canvas using canvas pliers and hold tension by applying pressure with your thumb.
Insert staples starting from the center staple and moving right with each new staple until you reach the right stretcher bar as shown. Use canvas pliers as needed.
Repeat the previous step for the left (3) and right (4) stretcher bars in that order. Remember to start from the center staple and move toward the arrows (as shown) as you staple the remaining two sides. Use canvas pliers as needed.
Now begin applying more tension when stretching the canvas using the pliers. Always have the canvas pliers facing away from your body during the final stretching and stapling steps for maximum tension and leveraging control. Starting closest to the center staple on the bottom stretcher bar (1), stretch the canvas, maintain pressure with your thumb, and insert two or three adjacent staples starting from the center staple and moving left.
Move slightly to the left of the staples you just inserted in step 41, use the canvas pliers to pull the canvas tight, apply thumb pressure to maintain canvas tension, and insert two or three more adjacent staples moving in the left direction toward the left stretcher bar.
Reposition the canvas pliers closer to the left stretcher bar, pull the canvas tight using canvas pliers, maintain pressure with your thumb, and insert several adjacent staples.
Repeat this process until you reach the left stretcher bar.
After inserting staples along the bottom (1) stretcher bar, your assembly should look like this.
Repeat steps 41 through 44 for the top (2), left (3), and right (4) sides – in that order until your assembly looks like this.
A good test to see if you stretched the canvas enough is to tap the center of the canvas with your finger and listen for a drum-like sound. If the canvas is improperly stretched and loose, it will not have this sound and flop around as you tap it. Also, if you see ripples in the canvas, you have an uneven tension problem – the canvas is not tight.
Now we must fold and secure the four corners. Hold the corner of the canvas material as shown.
While applying tension, wrap the corner around the stretcher bar as shown so that the fold is on the side of the assembly. The fold should run at a 45-degree angle, as shown.
While applying tension on the canvas material, fold it around the back face and hold it securely in the position shown in preparation for stapling.
While holding the corner in position, insert several staples as shown.
Repeat steps 47 through 50 on the remaining three corners. Be careful that your folded edges are always on along the side stretcher bars. Your finished assembly should look like this when viewed from the back. Use your hammer to insert all staples fully.
You have completed the 16×20 canvas stretching tutorial. Congratulations!
Please see our 8×10 Canvas Stretching Tutorial, a companion article to this 16×20 Canvas Stretching Tutorial, and learn about using canvas stretching pliers.
Before we start the Winsor & Newton Dammar Varnish Tutorial:
When to Varnish: Never apply final varnish to an oil painting unless thoroughly dried. Oil painting requires anywhere from 6 to 12 months (or longer) to dry, depending on the thickness of the paint. If you want to add a temporary finish to paintings that have not dried thoroughly, you should consider using a retouch varnish.
When Not to Varnish: If you have large sunken, i.e., dull and flat, areas on your original unvarnished oil painting, consider oiling out the painting before applying a final varnish. Varnishing will even out the finish on paintings that are reasonably even already, but if you have areas that are high gloss along with sunken sites “due to variations in the types of pigments and mediums used”, then applying a final varnish may not even out the finish as you might be expecting. Oiling out is suggested in such a case. If you decide to oil out your painting, you will need to wait an additional six months before applying your final varnish, and it’s best to perform the oiling out process shortly after completing your painting within the first few weeks.
In this tutorial, we will accomplish the following:
Learn a method for applying multiple thin coats of varnish.
Learn a brushing technique that will minimize uneven brush strokes that could be visible in the final product.
Achieve a high gloss finish similar to many paintings in museums, sometimes called a museum finish.
Additional points to remember when varnishing:
Use Good Ventilation: You will notice in the images used throughout this tutorial that I am working next to a window and using a fan to keep the air moving. Varnishing per this tutorial can take one to two days, so ensure your work area is adequately ventilated to prevent fumes from building up.
Brush Selection: The largest painting varnished in this tutorial is 12″x16″, and the smallest is 4″x6″. I chose a fine bristled brush that is 1″ wide. For paintings larger than 12″x16″, you should use a brush with a width in the 1-1/2″ to 3″ range. Only be cheap when purchasing a varnishing brush if you want to pick bristles from your varnish. Also, once you use a brush for varnishing, DO NOT use it for painting; if you have a brush you previously used for painting, DO NOT use it for varnishing. Purchase a varnishing brush that will only be used for this purpose.
Winsor & Newton Dammar Varnish:“You will need some Dammar varnish thinned 50% with turpentine. Turpenoid or mineral spirits will not dissolve the Dammar; it must be real turpentine.” I used Winsor & Newton Dammar Varnish for this tutorial, which comes pre-thinned (50% Dammar / 50% genuine turpentine). It is ready to be applied from the jar without further thinning. DO NOT shake your jar of Dammar because this could cause air bubbles to form in the varnish, which you want to avoid.
We are ready to start this Winsor & Newton Dammar Varnish Tutorial by John O’Keefe Jr. & Kate (Nelson) O’Keefe.
Step-By-Step – Winsor & Newton Dammar Varnish Tutorial
Assemble all materials and tools before starting.
1. Plastic Sheet
2. Paper Towel
3. Aluminum Foil Sheet
4. Varnishing Brush
5. Pure Turpentine
6. Dammar Varnish (Winsor & Newton)
7a. Ceramic Bowl (#1)
7b. Ceramic Bowl (#2)
8. Glass Pot for Dammar Varnish
9. Glass Container for brush cleaner
11. Unvarnished Painting(s)
12. Small Funnel (not shown)
Heat some water until almost boiling, and pour some hot water into the first ceramic bowl (item 7a).
“Be careful not to scald yourself with the hot water.”
Fill the ceramic bowl with enough water that the jar of Dammar Varnish (item 6) sits primarily submerged. Let the Dammar warm for about 5-10 minutes. Warming the Dammar will lower its viscosity without adding more turpentine, making applying easier. I recommend using a ceramic bowl because of the heat-retaining properties of ceramic – you want to keep the Dammar warm until you have finished applying a thin coat of varnish to your painting(s).
I have seen another tutorial using Winsor & Newton Dammar Varnish where the warming process I described was not used. In that tutorial, the Dammar was poured directly into a pot (without warming) and applied directly onto the canvas with a brush. The warming procedure I describe in this tutorial seems relatively common in other varnishing tutorials. With that said, some words of caution: “Varnish is highly flammable, so DO NOT use electric heating/warming devices while using varnish!”  The hot water method seems to be a widely accepted and safe alternative.
Before removing the jar of Dammar warming in the first ceramic bowl, pour fresh hot water (not boiling) into the second ceramic bowl. (item 7b)
“Be careful not to scald yourself with the hot water.”
Insert the glass pot (item 8) into the ceramic bowl with the hot water, ensuring that the glass pot is sufficiently submerged under the water.
You can use a different style container than I am using as long as the pot fits into the warming bowl without displacing too much hot water and has a large mouth to accept your varnishing brush. (See reference photo below that shows another artists setup)
Pour some of the warmed Dammar Varnish from the jar (item 6) into the glass pot (item 8) that is sitting in the warming bowl (item 7b):
“Notice I am holding the jar of Dammar with a cloth rag. Remember, the jar has been sitting in hot water.”
I used a 75ml Winsor & Newton Dammar Varnish jar and poured approximately 37ml into the glass pot. Generally, have at least 1/2″ of varnish in your pot. “Every time I add more varnish to the pot, I also change the hot water that the jar warms in(step 2)and the hot water that the pot sits in(step 3) to maintain the varnish temperature.”
Dip your brush (item 4) into the heated Dammar and lightly wipe each side of the loaded brush against the side of the glass pot (item 8) to remove excess Dammar:
If you begin brushing with an overloaded brush, you might develop a puddle of varnish on your canvas, and your coating will likely be too thick. On the other hand, if you remove too much varnish from the brush, you will not get enough coverage, and your brush will run dry before you can make one pass across the canvas.
Using the paper towel (item 2), touch the tips of the bristles to remove excess Dammar from the tip of the brush (item 4):
You might think that removing all this excess Dammar from the brush will leave us with too little varnish to cover the canvas. Our goal in steps 5 and 6 is to remove excess varnish, prevent puddling on the canvas, and prevent applying too thick of a varnish coating at once. At the same time, we want enough varnish in the brush so that we do not run dry halfway across the canvas as we move the brush from one side of the painting to the other. The technique we are trying to develop in this tutorial is the application of multiple thin coats of varnish.
With practice, you will learn how much excess Dammar to remove from your brush to prevent either of these situations.
Before we start applying varnish, let me explain the process briefly. We will apply varnish first in columns (along with the vertical axis of the painting) and then in rows (along with the horizontal axis of the image). We will brush on the varnish one column at a time, first in one direction, then back over the same brush stroke in the opposite direction. Once we cover the entire painting this way, column by column, reloading the brush with each back-and-forth pass, we will rotate the painting 90 degrees and repeat the brush strokes in the same back-and-forth pattern along the horizontal axis, row by row, but this time without reloading the brush with fresh varnish after each pass.
I have listed Winsor & Newton’s recommended application method for their Dammar Varnish: 
Apply the varnish in 1-3 thin coats rather than one thick coat. A thick coating will take longer to dry, may dry cloudy, drip, or sag during the application, and has a greater chance of showing brush strokes when dry.
Thinned varnish is more susceptible to producing bubbles. Refrain from being vigorous in your application.
Apply long, even strokes to cover the surface from top to bottom while moving from one side to the other. While working, inspect the varnish layer at all angles for bubbles. Even them out immediately.
Once you leave an area, stay within areas that you have done. If you do, you risk dragging partially dry resin into wet, which will dry cloudy over dark colors. Allow drying completely before doing any revarnishing.
Starting at one of the corners of your canvas, place your brush into position and in one long brush stroke across the painting. Make one long, even brush stroke from one side to the other side, and then leave it alone. Do not stop part way through. Do not return to touch up a spot you feel could be better unless you see a drastic problem, like large areas of no varnish or bubbles.
Reminder: Even though we have warmed the Dammar, we need to work quickly because once applied to the canvas, the Dammar will begin setting immediately. After about 10 minutes, the varnish will be tack dry.
After reloading the brush, make another long stroke in the opposite direction, directly over your first brush stroke. As we did with the first brush stroke, move the brush in one long, even stroke from one side to the other. (Note: I always apply my first strokes along the vertical plane when varnishing landscape. When I rotate the canvas to pass over the first varnish coating, I move the brush along the horizontal plane.)
Make a brief scan of your progress after each back-and-forth pass of the brush to ensure you’re getting even coverage. If you see large uncovered areas as you move across the painting, you probably removed too much varnish from the brush during steps 5 and 6.
However, if everything is going well, you should start seeing the difference the varnish has in the oil painting’s appearance. Notice how the colors are popping as if they were just freshly painted. (see step 9 image)
Repeat steps 5 through 8 until you have completely coated the painting with varnish. When starting a new row, you should overlap your new strokes slightly with the previous ones. The next step (10) is crucial for smoothing out the coating of varnish that you just applied.
Rotate your painting so that you will be working in the horizontal plane. Without reloading your brush, start at one corner, straight across the canvas without stopping, and then brush back over your stroke in the opposite direction. Repeat this until you have gone over the entire painting. This step will help to distribute the Dammar more evenly across your canvas.
At any point during the application of the Dammar Varnish, you might find a piece of debris has fallen onto the canvas. Using the tweezers (item 10), gently remove the contaminant while trying not to disturb the varnish.
Once you have completed coating your painting with varnish, place your brush into a container (item 9) with turpentine. You want to keep the varnish from hardening onto your brush while you wait for the varnished paintings to dry enough to continue with the second and third coatings.
Varnish is reusable, so you should pour, using a funnel (item 12), whatever you have not used back into its original jar (item 6). I recommend doing this between varnish coats. Let the applied varnish dry for a minimum of two hours between coats. However, the time might vary depending on the temperature and humidity in your area. If the varnish is tacky to the touch, it’s not ready for a second or third coating. I test my varnish by pressing a finger along the edge of the canvas. If I see a fingerprint, it’s not ready. One source said you could wait a day between varnish coatings.
If you apply two or more coats of varnish, please start this tutorial from the beginning, working on each new coat of varnish as if it were the first. This would mean starting again at step 2.
After about 10 minutes, the varnish should be tacky enough not to run or drip. Kate is here holding up the painting after she examines the varnish. Problem spots will be visible when looking across the surface of the canvas at eye level. Missed spots or uneven brush strokes will be visible. During this examination, you will decide if another coat of varnish is needed. “If needed, apply a second [or third coat] to fix rough areas after they dry. Do not try to fix areas by themselves, but apply a full second [or third coat] of the varnish.” I have found that three coats of varnish give me the best results.
Here I am varnishing another painting. I like to have several oil paintings ready before I start a varnishing session. Applying two to three coats of varnish can take one to two days, so I like to have several paintings ready. As I finish varnishing one, I move it aside and start my second, third, and so on. I then let them all dry together. I hope you enjoyed this Winsor & Newton Dammar Varnish Tutorial by John O’Keefe Jr. & Kate (Nelson) O’Keefe.
I was the featured artist in my Solo Exhibition by Mill House Gallery in Chester, Connecticut. Jane White contacted me with the invitation, which I accepted immediately. One thing I appreciate about solo exhibitions is they are a lot of work. I had to package and transport many paintings, hang and set up the entire show, create invitations, mail them out, and set the reception table. Also, several trips to the gallery were required: drop-off, opening reception, and pick-up. Despite all that was involved, the experience and enjoyment I received were worth it.
Event Literature – Solo Exhibition
Setting up the Exhibit – Solo Exhibition
Opening Reception and Meeting the Artist – Solo Exhibition
The opening reception was on a Saturday, and a steady stream of art patrons came to see the exhibit. Unfortunately, I was not the best host because I had a hurt foot and spent most of the time sitting on a chair in the corner. I had the opportunity to speak with most people who came to see the exhibition. There were many inquiries about the artworks and the techniques that I used, and I was surprised by the number of people interested in the stories behind each work. My solo exhibition at the Mill House Gallery was a great experience.
It’s time again for the 2010 Art Show & Sale at Cheshire Nursery by Cheshire Art League. I scheduled my time better this time, and I will attend the opening reception.
Drop-Off (10-8-2010) – Art Show & Sale at Cheshire Nursery
The artwork dropoff was scheduled for the day before the show was open to the public. Here are some pictures of my setup. I included seven Giclee reproductions, nicely displayed, and sold two.
Opening Reception (10-9-2010) – Art Show & Sale at Cheshire Nursery
The Cheshire Art League opening reception was held with another Cheshire Nursery art show opening reception sponsored by the local garden club members. That shows featured floral arrangements. Both receptions were well attended.
Floral Arrangement Show Opening Reception Space
Art Show and Sale Opening Reception Space
Cheshire Artists – 2010 Art Show & Sale
Art show receptions are always fun. They are a time to meet with longtime friends and make new ones. On this night, I met a very successful Connecticut artist, Tony Falcone. Tony, his wife Judith Andrews, and I talked for a while, and I look forward to meeting them again at future Cheshire Art League events. I also had the chance to hang out and chat with some other artist friends, Carla Koch, John Mackay, and Martin Gent, all fellow Cheshire Art League members.
Another great local set of shows. The 2010 Art Show & Sale at Cheshire Nursery by Cheshire Art League was a success. I got to meet Tony Falcone and his wife, and we shared a story about the time we crashed into each other in our cars but didn’t know each other at the time. It was during the ordinary course of conversation that we made the connection about that accident. We all laughed about it. Overall I had a good time.