How to Scale Up a Drawing in 4 Easy Ways and Save Time

scale up your drawing in 4 easy ways image header. A photo and a drawing of a lion

Time is precious and sometimes you need a quick and easy way to scale up a drawing. This post will guide you through the 4 practical ways to enlarge (or reduce) your image.

Grid your reference and enlarge or decrease the ratio to draw a grid on your paper. Copy each box in proportion. Measure two points with scale dividers, the reverse end will mark those same points on a different scale. Enlarge a photocopy to size, shade the reverse side, flip it over and trace the outline. Project the image onto a wall or canvas and trace the outline.

No fluff, let’s jump right in.

How Scale Up Your Drawing Using a Grid

The idea is very simple. You grid your reference and draw another on your drawing paper and copy each box. There’s a little more to it, naturally.

Accuracy is everything with this method. Your grid must be spot on or things will go wrong. Drawing an accurate grid is more difficult than it looks.

Make a few photocopies of your reference photo. Now try to measure out the grid using a ruler. For argument’s sake, let’s say you are marking out a 1-inch grid (25mm). A pencil dot every inch, what could be more basic? True, but it’s seldom accurate.

Most folks miss their mark and that has a knock-on effect. Plus when you draw the gridline between two dots that has to be accurate too. You have to be precise twice. A double whammy.

You can use the width of the ruler and draw lines along both edges. It’s more accurate than measuring each dot. If the boxes are too large draw diagonals within the boxes, don’t measure the halfway point or you’ll be inaccurate again.

how to scale up a drawing with an accurate grid. A close-up detail of a lion photo with grid lines and a ruler.
Draw the grid the width of a ruler and use diagonals to sub-divide

If you have a technical drawing board it will be easier to get things right. If you use one, use low-tack framers tape to secure your paper. You don’t want to tear the edges of your paper.

Use the slider to place your horizontal lines and a CLEAN set-square to line up the verticals.

What a PHAFF.

Try this instead, grid a digital file. You’ll need a photo editor. If you know your way around simple photo-editing then download the grids below and layer them onto your image. If not, then use a free tool called Pixlr.com and follow these instructions.

screenshot of pixlr demo of how to add a grid layer to scale up a drawing

This is your landing page. there is no need to sign up and login. Click the ‘open image’ button.

screenshot of pixlr site, demo of how to add a grid layer

Your chosen file image will appear in photo editor. Now click the plus icon at the bottom right (+).

screenshot of pixlr.com demo of how to add a grid layer

This dialog box will pop up. Click the image box. Find your grid file and open it into the editor.

screenshot of pixlr.com demo of how to add a grid layer easily to draw to scale

The grid will be a new layer and appear on top of your original image. The arrows point to both layers in the sidebar. You can adjust the top layer if you wish.

screenshot of pixlr.com demo of how to adjust a grid layer easily

If you click the cross icon in the top left corner you will be able to move the grid up and down. Move the pointer over the grid and left click the mouse (and hold it down) to reposition the grid. You can enlarge or reduce the grid by dragging the blue corners diagonally.

screenshot of pixlr.com demo of how to add a grid layer and flatten the image easily

When you are happy as it is, flatten the image. This locks the layers together into one image.

screenshot of pixlr.com demo of how to add a grid layer and download it easily

Download your file with a perfect grid. You will never draw a more accurate grid and it will only take you a few minutes.

You can draw a larger grid on your paper and work from the gridded file from your computer screen. I hate doing this.

If you have a printer, enlarge several copies to various sizes and print them off. Choose the copy size you’d be comfortable drawing and use that scale to draw it out, 1:1. Far easier.

If you don’t have a printer (and I don’t) get an instant photo printed and photocopy it, again in several sizes. I nip into my local library and do it there.

N.B. if you are going to print a photo make sure you have a large file so it doesn’t pixelate.

If you lay your gridded photocopy onto your drawing surface you can mark the lines accurately by using the copy as your ruler.

Draw the grid very lightly over your drawing paper. You want to avoid heavy lines that won’t fully erase and you certainly do not want to leave score lines. Sounds obvious but it’s so easy to overlook.

I’ve drawn backgrounds just because I was too heavy-handed and needed to disguise the grid lines somehow or face starting again. Be warned.

Download Your Grids for Free. No Catch

How to Scale Up Your Drawing Using Dividers

If gridlines are not for you and you want to retain more of the sketchy style and feel. scale dividers will help.

Put simply, dividers are two pointed bars joined together by a pivoted slider or peg holes. The artist measures two fixed points on their reference with one end of the dividers and, using the other end, marks out the corresponding points on their paper. The new scale will be true and accurate with every subsequent measurement.

Further Reading: How to Plan and Compose your Art (A guide for beginners with examples)

The great advantage of using proportional dividers, in my opinion, is how they allow you to retain the feel of freehand movement in your sketch. Using a grid is so precise it’s easy to lose any sense of spontaneity.

Dividers allow you to pinpoint the key features of your subject, such as the distances between the eyes, tip of the nose, and lips, etc, and mark them down with certainty.

So how do you set the correct scale? It’s simple really. With a very light touch, you sketch out the basic shape you want the drawing to be. For example, if you are drawing a portrait, draw an oval that feels comfortable for you. That’s the scale we are going to use.

proportional dividers used for scaling a sketch
A cheap pair of proportional dividers

Now measure the dimensions of the head on your reference with your dividers. Place the other end over your sketched oval. Where do the points touch?

Move your peg (or slider) up, or down, a notch until the proportions line up. One narrow end will measure the reference head and the other will be roughly the width/height of your oval. Voila

Now mark a spot somewhere in the center of your reference. This will be your measuring point. Everything will be measured out from this dot. You can measure the radials from this center point.

The distances will be accurate but if you’re not confident you’ll still miscalculate some of the angles. Let’s say you’re drawing the eyes. You may think they are on a horizontal line, in fact, the head might be slightly tilted and one pupil is lower than the other.

In that case, you will benefit from drawing one vertical and horizontal line centered on your spot. Now you can measure from both the center spot and the nearest line. Your true angles will be easier to see.

Good dividers are hard to find for a reasonable price. I bought a cheap wooden pair (above) and they are not accurate enough. I ordered a pair of cheap plastic Prospek dividers which looked much better online but they weren’t.

Lastly I ordered some cheap brass dividers online and they are much better.

How Scale Up Your Drawing Using a Photocopy

What if you are in an insane hurry? You have a deadline to meet and need to get the work done quickly, what then?

You can always trace a photocopy. I saw portrait artists in Thailand draw this way.

Enlarge a photocopy to the desired size and, using a soft grade of pencil, shade the back of the paper with a layer of graphite.

Flip it over and tape the top edge to your drawing paper using low tack tape. Now, using a medium grade (HB), trace the key lines without pressing too hard.

You can lift the paper now and again to make sure the tracing is transferring properly and you have all the most important features marked out.

Further Reading: Is it Cheating to Trace your Art? Is it Really OK?

Some graphite will transfer with the weight of your hand pressing onto the copy so you may have to tidy the tracing with an eraser.

You now have the all the proportions you need to crack on with the job.

Why not use a lightbox?

A lightbox, if you don’t already know, is an opaque screen backlit with a strong light. The artist tapes and preliminary sketch or photocopy onto the screen and tapes the drawing paper over the top of that. The artist then traces the outline.

I did own a lightbox many years ago but it only worked well in a darkened room and was only good for tracing onto thin paper. It was expedient for drawing commercial work, where time mattered, but it always depressed me slightly. I hated drawing in a darkened room, even if it was only for 20 mins.

How Scale Up Your Drawing Using a Projector

I also experimented with projectors many years ago. In those days there were three choices, slide, overhead, and opaque projectors. Now you have digital projectors that are far better.

I owned an opaque projector back in the 80’s and amazingly they are still manufactured to this day and called Artographs.

They work by projecting a photograph, printout, or sketch, onto a vertical surface. You place the photo under the projector. A bright lightbulb shines the image onto a mirror, or prism, and bounces the light back through a lens and projects it onto a wall or canvas.

There are major drawbacks.

  • To get an image in proportion the projection must be at a fixed 90-degree angle or it will distort the image.
  • The cheap models can get so hot the bulb can buckle paper or even melt a photo.
  • They can only project from small images.
  • They need a darkened room.
  • They are expensive for what you get.

I can’t think of a good reason to use one. The same can be said for slide and overhead projectors. They are relics.

If you wish to project an image, buy a cheap LED digital projector. You can pick them up for $80-$100 easily enough. They are small, don’t overheat, and portable.

The LED bulbs are super bright and even the cheaper models exceed 2000 lumens; that’s blinding. They are so bright you can use them in daylight. No more darkened rooms. The more expensive models are perfect for muralists.

All you need is a digital file, a tripod, and a spirit level to align your image properly, and off you go. You can project the picture to your desired size and the tracing will only take minutes.

Conclusion

Four easy ways to scale up a drawing. If you are drawing solely for pleasure with no commercial pressure I would recommend you use the proportional dividers. They will teach your brain to see in the right way. Eventually, you will use them less and less and see the proportions without a drawing aid.

If you are stuck for time, tracing is the quickest way to get something usable on paper.

If tracing is a step too far, use a grid. It’s laborious but you’ll get results.

I draw my work in public and use the grid method because I fear going wrong in front of an audience. It’s foolproof and perfect for photo-realism.

Happy Scaling


If you found this article useful, you will like these related articles:


Keep in Touch

* indicates required

PIN IT AND SAVE IT

4 ways to scale a drawing image for pinterest. Lion photo, dividers, lion drawing.