Stretcher Bars - when to add Wedges ?

[Bagpuss]

I've just had some Premium Stretcher bars delivered from LION. I have stretched canvases in the past but have not done load of them and more often than not I have used stretcher moulding cut to size.

I was looking at the LION leaflet about canvas stretching ;
http://www.lionpic.co.uk/InfoStore/Info ... x?s=canvas stretching&catid=0&docid=1309

I'm a bit confused at what point the wedges go in ? Do they go into the stretcher bar corners before stretching the canvas or are they put in right at the very end to give extra tension ? Or does it matter ?

Bit of a basic one I know .... sorry
Thanks in advance,
Adam/Bagpuss

[WelshFramer]

No idea as to the 'official' method but I'd put them in after stretching the canvas as that avoids the risk of them falling out during the stretching process. If they fall on the floor it's no problem but if they fall between the canvas and the bar then you can get a nasty dent in the canvas.

I've always been told:

1. Count the wedges before applying the backing paper: just to make sure none have fallen out

2. Put a blob of glue on each wedge to glue it to the frame: just enough to hold it in place but not to much as the bond will need to be broken for restretching.

3. Give the framed canvas a little shake before handing it to the customer just to ensure that there are no loose wedges, screwdrivers or other bits and pieces inside.

[Bagpuss]

1. Count the wedges before applying the backing paper: just to make sure none have fallen out

Thanks for the swift reply,
Where do you place the backing paper Mike ? Does it cover the back of the moulding and the stretcher bar or completely cover the back of the frame ?
Adam/Bagpuss

[birdman]

Hi Adam,

We always stretch first, and then add the wedges. If you have stretched the canvas correctly it should be taught and drum like if tapped. The wedges are for later as the canvas relaxes over time. Two for each corner and they need a little tap in just to ensure they stay put but not enough to stretch the canvas any more. From the GCF study guide:

"Add the wedges to the long sides first, and then the short sides: this helps prevent the frame going out of square and corner rucks developing. This process is often referred to as 'keying-out'. When keying-out it is a good idea to place a square of mountboard under the corner so that there is no danger of the hammer damaging the canvas."

I've also heard that some framers tie the wedges to the frame with thread or wire, so that they don't get lost. Don't do that myself though.

Hope that helps.

[birdman]

I forgot, we have never used backing paper for oils, we may tape over the staples/framers points to make it look tidy but we've always left the back of the oil open, rightly or wrongly. I have seen some with a proper back enclosing it all. I guess it's down to personal preference and cost.

[markw]

Add wedges at the end. Most wedges stay in place - you do get some wedge systems that always want to fall out - fasten these to the edge of the stretcher bar with fishing line - drill small hole in wedge - either small screw - or small hole drilled in stretcher edge.

[Nigel Nobody]

Wedges go in after the stretching is complete. They should be pushed or tapped in so that no additional tension is placed on the canvas. They are in place so that at some future time if the canvas relaxes too much, more tension can be applied then.

The hypotenuse of the wedge should lie along the inside of the stretcher. A hole should be drilled in the end of each wedge so that a string can be tied to it, then the string is stapled to the back of the stretcher, pulling towards the corner of the stretcher frame so that the string doesn't allow the wedge to come out.

[Not your average framer]

Where I worked while being trained, I had to assemble and square up the stretcher bars before stretching batches of canvases.

To make this easier, they had two pieces of wood fitted at right angles to each other on a large piece of chipboard, together with a mallet for tapping the assembled stretches to be square with each other.

I have continued the same practice myself. It works well!

[Bagpuss]

To make this easier, they had two pieces of wood fitted at right angles to each other on a large piece of chipboard, together with a mallet for tapping the assembled stretches to be square with each other.

What a great idea, the simple one's are always the best I've got a few more canvases to this week, I'll give that a go : )

Thanks,
Adam/Bagpuss

[WelshFramer]

Where do you place the backing paper Mike ?

I cover the entire back of the frame assuming the rebate is deeper than the stretcher. Normally I wet the Kraft paper, leave it while I smear PVA arond the frame back then put it in place. Needs a little practice to get it right first time. It looks dreadful when first done but once the paper has dried it's drum-tight and smoth.

Saves dirt and dust getting between the canvas and stretcher.

[JamesC]

I cover the entire back of the frame assuming the rebate is deeper than the stretcher

That also assumes you are framing the stretched canvas then? Just in case anybody learning was confused by that.

Papering the back is belt and braces and I would only do that if there is the budget or it's valuable/requested - it will make a good impression but is extra work not needed in every case. Likewise with the wire in the wedges only if there is danger of losing the wedges e.g they are loose fitting or the customer has to move it around a lot.

Defo agree it's wedges at the end and only tap them very slightly to allow the maximum future tightening - get a white mallet and it won't mark the canvas back like a black one can. Otherwise wrap your mallet with tape. Place some mountboard behind the wedges as you tap them if it's a rare occasion you do them.

[Roboframer]

I nearly always cover the back of canvasses, but with board; not paper, for protection, I also sell a fair amount of stretched canvasses glazed, I ask the customer which they'd prefer.

a. Pay someone (in time) to clean and maybe re-varnish their oil.

b. Clean a piece of glass themselves.

It should be a no-brainer, and if they give it 'Oh but I don't like the look of glass' I show them museum glass and watch them try to talk their way out of that one!

I win some.

[Not your average framer]

get a white mallet and it won't mark the canvas back like a black one can. Otherwise wrap your mallet with tape. Place some mountboard behind the wedges as you tap them if it's a rare occasion you do them.

I use a small hammer and protect the canvas by placing a piece of scrap mountboard against the canvas. For the same weight a hammer is generally more compact than a mallet and therefore easier to use in a restricted space. This is also the way I was trained to do it.

[Nigel Nobody]

A very small hammer is much safer than a hulking great mallet. The wedges need to be gently tapped into place. Some wedges are a loose fit and can be pushed into place. Even more important to tie those in place.

As Robo said, a hard backing is the way to go with canvases as it protects the canvas from intrusions from the back. It also keeps out dust, grit, chunks of stuff and insects, which could end up in front of the stretcher and lodged against the canvas at the front.

[Bagpuss]

Thanks for everyone's thoughts on this, I did two smallish canvases yesterday using Premium Stretcher bars from LION, I feel like a pro' now ! Next week I have two canvases that are 120 x 90cm approx. with double brace as well.... hardcore !

cheers,
Adam/Bagpuss

[WelshFramer]

Papering the back is belt and braces and I would only do that if there is the budget or it's valuable/requested - it will make a good impression but is extra work not needed in every case.

I never bother to charge for papering the back. There's a roll of Kraft paper attached to the bench end (I use it to keep the bench clean). So pull out a piece of clean paper, spray with water, wipe some glue around the frame, slap on the paper, trim to size, spray with water again and put it aside to dry. Takes about 10 minutes.

I sometimes paper the backs of other frames as well if I think it will look neater that strips of sticky paper.

For posh jobs, for which I do charge, I use Lion's Fleur-de-Lis paper. Looks really nice but it's not as easy to handle as Kraft paper when it's wet.