View Full Version : Painting straight lines.

10-31-2011, 12:13 PM
As I've got older I've found it increasingly difficult to paint a straight, narrow line accurately. The short answer to that, I suppose, is don't paint straight, narrow lines. Trouble is that the kind of paintings I like to do often contain several SNL. None more so than my recent post to WOYE in which my latest painting depicted a scene from my home town. Until I'd got well into the painting I had not realised just how many SNL I was going to have to paint. The guard rails on the bridge were the acid test and there were no less than 420 SNL required varying in length from 15mm to 35mm.
I started off carefully in freehand but after 140 SNL I realised that they were not good enough and I was going to have to paint them out and start all over. I practised "paint-ruling" as described in WC forums i.e. "take a piece of strip wood and angle it so that the ferrule of the paint brush makes contact with the upper edge of the wood then paint the line." That's OK as fas as it goes, but whilst the steepness of the angle will allow this method to be adjusted to suit different sized brushes, the arrangement is rather unstable in use. Then I came up with the simple idea of making a stable paint-ruler using low cost mount backing grey card which is 2mm in thickness. The prototypes were made specifically to suit the lining brush that I was going to be using in which the hair length was 7mm. For the long ruler I cut three strips of card 45mm in width and one strip 55mm in width. The narrow strips were stuck together using several spots of super glue and the wider width stuck on top with an overhang of nominally 5mm either side. It is not necessary to be precise in aligning the card strips - the only important issue being the provision of a clean cut on the two ruling edges. I made a smaller version by cutting three squares of 45mm side with one square of 55mm side giving me four ruling edges. Some idea of their looks can be seen in the photograph below.


With a 45mm base the rulers are lightweight and completely stable when held against the support. In the initial test I found that the best way to proceed was to hold the brush at an angle so that the ferrule was in firm contact with the ruling edge. The result of the initial test is shown in the second photograph (apologies for the glare) which includes a 40mm sewing needle and British penny to give an idea of scale. The idea seems to work OK so the next thing is to devise a way to make the ruler adjustable to accommodate different brushes and hair lengths (I'm working on it) and then get lots of practice to ensure that brush pressure is even throughout painting the line.


Another method of dealing with straight lines in a painting is the use of masking tape. Also shown on the second photograph is a short piece of standard 19mm wide masking with a piece of 6mm embroiderer's masking tape shown for comparison. The narrower tape has proved very useful in some situations but it tends to be of a higher tack rating than normal masking tape and so should only be left on a painting for the shortest possible time.

10-31-2011, 05:53 PM
bertschikon. A neat solution to a particular problem (I'm not getting any younger either)! Looking at the pictures and noticing the blue paint on what appears to be an 'angled cut edge'. I would guess that you are using your device with the larger square down on the surface to be painted. If I am wrong, sorry! If I have guessed correctly, there is a simple solution to your 'variation of brush size/hair length' problem. Use the device the other way up. That is with the smaller 'pedestal' on the surface. By using additional temporary pieces to increase the height of the pedestal you can account for increasing hair length. It will also give you more clearance to see the exact location and width of any line you draw.paint.

Hope this helps.


Charlie's Mum
10-31-2011, 06:42 PM
Hmmm - now I assumed that Doug was using the support with smaller side down and the overhang as the guide for the brush! :lol: ..... like a ruler with a bevelled edge.

My question - what's the consistency of the paint Doug to keep that even throughout the line?

10-31-2011, 07:57 PM
Could be the camera angle giving the impression of a beveled edge. We need just a bit more clarification on the method of use.

10-31-2011, 08:10 PM
Thanks for the comment Autolisp but Maureen is correct in assuming that the device is used smaller side down to get the benefit of the overhang. There is still some tuning to do in order to determine the optimum height of the overhang for brush hair of a given length in order to ensure that the ferrule makes good contact with the edge of the overhang. Angling the brush to the support helps in this of course. Thickening the narrow part of the rule seems to be the solution to accommodating brushes of significantly different hair lengths and I'm looking into the possibility of making a number of "add-ons" of different thicknesses. The main problem seems to be the method of temporary attachment to the basic rule.

Maureen, the paint consistency used to make the lines in the test piece was that of single cream. I was using Golden's fluid acrylics with a little flow improver added and a sable brush for its "pointability" and spring. The little test piece showed only relatively short lines which could be painted in one pass with a pretty small brush. A larger brush carrying a higher paint load would be needed to create longer lines in one pass and I'll be looking into to this to see where the limits are.

11-01-2011, 03:45 AM
thanks for your post i will be trying to create a similar set up, the reason i being is i have parkinsons so i normally stay away from paintings that require straight lines limits my repatoire, thanks again.

11-01-2011, 05:28 AM
bertschikon "The main problem seems to be the method of temporary attachment to the basic rule." Why not drill a small hole in the base and glue a short pin in it. Drill a corresponding hole in each of the 'various thickness' add-on pieces. That should locate each new thickness base in place for you.


11-01-2011, 05:52 AM
Thanks for your continued inteest Autolisp. I like the idea of a pin, say 3mm, being fixed to the bottom "add-on". Again there would be no need for great precision because the 45mm wide base does give great stability and the 5mm overhang is ample to allow for a certain degree of slack in the fixing.

Positioning the rule is made easier by marking in the positions of where the lines should be. For this task I use a sharp water colour pencil over the existing paint. Chinese white is good against most colours and Van Dyke brown for the lighter colours of paint. Only the lightest touch is needed and when the line paint is dry a wipe over with a damp cloth will remove every remaining trace of the water colour pencil.

11-01-2011, 07:11 AM
Hi Ric, I was sorry to learn about your Parkinsons and hope that you are able to make up one of these simple "paint rules" to help in broadening your painting repertoire. I've only been making use of mine for a couple of days and am delighted at the difference it makes when "lining".

11-01-2011, 09:12 AM
Another approach would be to use a ruler, metal or wood, and raise one edge from the surface. This give an edge to run the brush ferrule on and it can give an excellent line without creating something. Longer lines, longer ruler. Other brush alternatives may be useful as well.

Just a thought.

11-01-2011, 10:55 AM
Thanks for the tip Idylbrush. Something similar was suggested in this or another WC forum recently and I've tried it without much success. Using an angled ruler or stripwood requires that one has to concentrate on maintaining a constant angle for the ruler and a constant pressure on the brush in order to achieve a straight and even line. The great advantage of the flat base is its ease of alignment to where the line should be and absolute positional stability allowing full concentration on brush pressure.

There is rarely anything new under the sun these days so I'm sure someone must have come up with a similar flat base rule in the past without people becoming generally aware of it.