Tuesday, September 15, 2009

Stretchers

I will begin this post by announcing again the meeting place for my workshop in Jaffrey, New Hampshire. We will meet at 9:00 on Saturday, September the 19th at the Civic Center parking lot, at 40 Main st. I have a full class and I am looking forward to meeting you all.

I am laying plans for several more workshops. If you would like to help me organize one where you live please let me know. I have been talking to an inn located in the White Mountains of New Hampshire near Franconia. I am tentatively thinking of doing a workshop there at the end of October. I don't know how long it will run, but I am kicking around the idea of a longer workshop, maybe five days. That would allow me to go deeper into the ideas I present than a weekend or three days. If you have an interest in this, please let me know.
( stapletonkearns@gmail.com )

These are stretchers, sometimes the art supply stores call them stretcher strips. That sounds really amateurish to me. Stretchers come in number of different weights and styles. The trick is to have as many on hand as you can, in as few styles and weights as you can. Compatibility is always a problem. Two 24" stretchers from one company will not mate with those from another company. Sometimes they wont even mate with stretchers from the same company. Its a nuisance. So if you can, choose a supplier, buy your stretchers mail order, by the case and from the same manufacturer.

If you are buying stretchers retail, it is important not to just grab them out of the box and head to the sales associate with the gauges in his ears. Just like at the lumberyard, people have picked through the stretchers and left the warped, twisted, crowned or bowed ones on top. You need to dig down into the supply, pull out some likely candidates and then sight down them. Hold them by one end and look down the length of them on the side and the edge. If they are snaky, throw them on top of the pile and then dig for a better pair.

Notice also the condition of the bead, that's the raised, half round area on the outside edge of the stretcher that holds the canvas away from the panel of the stretcher, check that it is not dinged at the corner where it will meet its neighbor. If they are shoved in an out of the box roughly they get damaged there, as they are soft pine. If they are damaged there, they won't meet nicely at the outside corner and when you stretch your canvas on them , there will be a defect causing a dimple or a crease.

There are three different weights of stretchers pictured above. I think the narrow, ordinary stretchers are OK up to about 24" or maybe 30" but not beyond. The mid weight are good to perhaps 30" or 36" and anything larger than that should be on the heavy duty stretchers. A 30"" by 40" for instance should be on heavy duty stretchers. If you use stretchers that are too light they will either "bow-tie" or twist, both are a real nuisance. Making little triangles out of plywood and adding them to the back of stretchers is amateurish, don't. Use the right gauge stretchers instead. Someone buying your painting will notice the stretchers, if they look cobbled together you might lose the sale. Even one lost sale every few years, would cost more than using the correct stretchers.

There are a number of high tech stretchers on the market that have aluminum spines or are made of old growth redwood with the spotted owls still clinging to them. I think they are way to expensive to be useful unless you only make a few paintings a year and get big money for them. I have seen the backs of thousands of valuable antique paintings and they almost without exception have very simple stretchers like the ones pictured above. That is, unless their original stretchers have been replaced by some restorer who talked his client into the obsidian and polyvinyl chloride MOMA stretchers.

I think canvas on stretchers that are marketed as paintable on the sides are horrid, I guess if you are in the modern art market or an art school they might be alright. In my world they are not. Pictures need to be framed in the galleries I am in. I think that painted side look is going out anyway. Remember linen liners? If you need the modern look, use shadowbox frames that float the canvas or steel frames that come in an assortmant of colors and finishes.

I assemble stretchers by laying them on the floor and trueing them up with a framing square. That's a T shaped thing that looks like two rulers put together. It is an inexpensive carpenters tool and is made out of steel. If I am traveling and don't have one, I assemble the stretchers and then fit them into the frame of a prehung door or window, preferably a steel door frame as they remain more true than the wooden ones.You can also pull measurements with a tape measure across opposite corners. I seldom do that as it is to mathematical for my left brained artist sensibilities.. The mechanical methods are easier.

I tack or staple my stretchers together at the corners so they don't shift when I start stretching my canvas. I don't intend to use stretcher keys, so it isn't a problem, if I do want to key them out I can remove the tacks. On oversized stretchers I use squat, little wood screws or short shanked sheetrock screws that I can drive with my battery drill. Gotta go easy with those, so as not to split the wood.

For some reason the manufacturers don't always mark the size on stretchers anymore. I am sure it is easier for them, but it is a nuisance for me, so I keep a yardstick next to my stretcher collection. I have boxes of each size I use. I usually buy pairs of boxes at once. For instance I might buy 16"s and 20"s at the same time. that way I can stretch a whole lot of 16" by 20"s and know the stretchers are going to be compatible.

See you tomorrow.

12 comments:

Sara Winters said...

Thanks for the info- it came at just the right time for me

Philip Koch said...

Craftsmanship and art are two different things. But when I think of the thousands of paintings I've seen over the years, many of them by student artists, I can't think of a single case where a lack of craftsmanship in the stretching of the canvas helped the "art" part to happen.

Glad to read this post too as I was starting to worry that I was the only person who would admit publicly that I judge a painting by its back side. If the back looks amateurish, and so often they do, it plants seeds of doubt in your mind about the quality of what's on the front.

Bob Carter said...

Stape-
Several years ago I gave up using strips from the big F manufacturer. I swear the wood is from recycled orange crates, and too often the ends are mis-cut. I currently use Best/Utrecht strips, which are a harder wood (spruce?), but they are often made from two pieces joined with a zigzag union. If you hit that join with a staple it may not go in fully. I'd like to find something with the strength of the Best strips but without the join. Any suggestions?
-Bob
P.S. Greg and I made the bike trip from Boston to Provincetown through driving rain in about 8.5 hours. Not too wimpy ... :-)

willek said...

I have used a lot of stretcher bars like those pictured on the left in your opening shot. They look great in theory, but that high lip on one side prevents the canvas from hitting the bar. If you do need to stretch the canvas made up with those stretchers there is a fault in the design. As you bang in the keys, the tenon come out of the mortice. The added pull of the canvas on the high lip has an extra mechanical advantage over that of a normal double lipped stretcher bar... and the framework curls upward and inwards. A better scheme would be to use a single slotted corner and a single straight-through stiffener. Tightening could be acomplished by a single tapered dowel inserted into a single hole drilled into the corner, above the stiffening slot... I think I will patent this...

Unknown said...

I have never stretched my own canvas because the stretcher pliers seem so expensive for such a simple tool. Is that just the price of admission, or is there a good, low-cost alternative?

Stapleton Kearns said...

Sara:
Thanks
..........Stape

Stapleton Kearns said...

PhiliP:
Craftsmanship and art are two different things,but given my druthers I will choose good craftsmanship over bad. I also prefer a faster car, a bigger cigar and leather upholstery.
...........Stape

Stapleton Kearns said...

Bob
What you are talking about is called finger jointing. I don't mind it as it makes the wood more stable.
125 miles on a bike, wait till you get to be my age!
......................Stape

Stapleton Kearns said...

Willek;
I have not had a problem. But I don't key my stretchers out, at least not often.

What if you put a capacitor hooked to a twin plungered solenoid on a sliding kevlar- graphite track held in place by solid molybendium clevice pins?
..............Stape

Stapleton Kearns said...

Jeremy
You have to be able to stretch canvas. Jerrys artarama has a set of canvas pliers for 9.99, I am sure they are primitive but they will pay for themselves real quick. They are cheaper than a box of pampers for that new babeopod.
....................Stape

Unknown said...

Jeremy,
Or just use zircon encrusted tweezers.....

"ortilize" to convincingly tell untruths during a public address..
oh wait... that definition is already taken.. see "politician".

willek said...

Hey, well said...Stape, why didn't I think of THAT!!