How To: Using SVG files to Cut Foam for Fly Tying

Introduction

In this publication, I would like to explain the pros and cons of using die cutting machines for cutting foam bodies for fly tying when compared to using the standard “cookie cutters” on the market today. Both methods produce consistent results. However, the efficiency of the die cutting machines is unrivaled.

I will also give a tutorial on how to use the SVG files with your cutting machine to quickly and easily produce hundreds of foam bodies in minutes. My experience is with using Cricut machines and software. Therefore, I will use Cricut for my examples and tutorials. SVG files can also be used for Silhouette cutting machines, but I have not used them personally. If your experience is with the Silhouette machine and software, you should be able to easily adapt my instructions to meet your needs.

DISCLAIMER: This article contains paid Amazon Affiliate Links to some products. If you purchase from these links, I will earn a small portion in commission. This helps me keep this document available online and free for everyone.

What is an SVG file?

Don’t worry, I am not going to bore you with in depth technical details, but it is important to learn why SVG files are so useful. SVG stands for Scalable Vector Graphics. Great! Now what does that mean and why do you want to know this? The short answer is that these graphics files can easily be resized without losing any quality and it keeps the original shape pristine. You may have noticed when using JPG, PNG or other graphics files if you try to make them larger or smaller, the resolution quality may become poor and pixelated. That is because those formats are not scalable. The SVG file does not have this limitation. Later in this document you will see why this is such an important feature of SVG files.

SVG Files VS. ‘Cookie Cutters”

Initial Cost

The startup cost of buying a cutting machine may deter some from using this method to cut foam. However, as in the breakdown below, it is not nearly as costly as one may think. I used MSRP for these values. That said, you can frequently find cheaper prices on Amazon or during sales. In fact, the affiliate links in this article link to Amazon with prices well below MSRP. For this example, I am looking at buying everything needed to cut 10 different foam body patterns. However, the main advantage of the cutting machine is that you can cut ANY shape you desire! Also, foam cutters seem to be hard to find in stock these days. SVG files are digital, so they are always available!

SVG Files	Foam Cutters
Cricut Maker (or newly released Maker 3) $350-$400	Cutters average about $15 each (if you can find them in stock!).
Knife Blade Attachment $45	Sets include all sizes (ex. Small, Medium, Large) needed
Strong Grip Mat $15	for a specific pattern and cost about $55 per pattern.
Brayer $15
SVG Files (10 Body Patterns) Free-$50
Total Investment = $425-$525	Total Investment for 10 Patterns = $550

Maintenance

When metal is used to cut materials, it is eventually going to lose its edge. Therefore, there will need to be replacements at some time. Luckily, you can buy replacement blades for die cutting machines. As for foam cutters, you may need to purchase new. NOTE: The manufacturer of the cutter may replace at no cost, but you will likely need to send the cutter in for replacement or possible sharpening.

SVG Files	Foam Cutters
Replacement blades = $20	Replacement cutters = Free-$55 per set

Efficiency

When you see the tutorial for cutting bodies, you will see that I cut hundreds of bodies at a time. I also arrange the bodies in a manner that utilizes as much foam area as possible. It is easy to measure the bodies to be the exact size needed for the hook I am using. Because of this, I can cut a full sheet of bodies in 15-20 minutes with very little foam waste. In fact, I even use the waste foam as sight indicators on my flies! I can also cut bodies in multiple sizes at the same time. Cutters can punch out one body at a time. You can try to arrange the bodies to make efficient use of your foam and if you practice, you can cut the bodies quickly. However, you are not going to compete with the “X-Acto knife on steroids” that is the die cutting machine.   

Versatility

Find a sheet of foam that is the perfect chartreuse color and want to make multiple body types in multiple sizes? The cutting machine can do that as easily as you can copy and paste. Sure, foam cutters can do so also, but you need to 1) have multiple pattern cutters available, and 2) have multiple sizes of those cutters. Also, when using cutters, you are restricted to sizes that are a general rule of thumb. On the other hand, you can adjust SVG files to be any size you want for any hook you have available. That is versatility at its finest!

Both cutting machines and cutters can also cut other materials (wings, wing pads, thin skin, etc.).

Where do you find SVG files?

SVG files can be found on many websites online, or if you are a bit handy with computers and graphics applications you can make your own. I use Adobe Illustrator, but plenty of other applications can do the same thing and some are even free.

Shameless self-promotion time … I own and operate Fossil Fish Fly Shop and I have all my SVG patterns listed for sale Here and in my Etsy shop. If you are looking for a custom SVG file, please reach out to me at ron@fossilfishflyshop.com to see if I can accommodate you and for a quote.

How do you use SVG files?

Now that we have those details out of the way, we can get down to the business you are truly here for .. learning how to use SVG files to cut your foam bodies. For this tutorial, I am using a foam pattern that I like for small hopper and even cicada flies. I will also cut bodies for multiple sizes of hooks. As I like two tone bodies, I will also demonstrate cutting two colors of foam at the same time.

My configuration and quick tips

Cricut Maker – I use the Maker series as it can use the knife blade attachment. You can also use a deep point blade, but the cut is not as clean as the knife blade.
Knife Blade & Assembly
Strong Grip Material Mat
2mm Craft Foam – I have found that the Cricut works fantastically with 2mm foam. You can also use 3mm Craft Foam with relative ease. However, with 3mm foam, be sure to use the brayer to roll out and flatten the foam as much as possible just before cutting. If you fail to do this, the rollers may not compress the foam enough and cause a material jam. If thicker foam is needed, I typically glue together multiple bodies. The knife blade will try to make two passes to fully cut the foam, however, I have found that this is not needed. You can stop the cutting process after the first pass with no ill effect.
Brayer
Cricut Design Space Software

Step 1.
Measure your hook(s) to help determine what size you want your bodies to be. In this tutorial, I am going to tie on #10, #8 and #6 hooks. As such, I have taken measurements of the length of the hook taking into consideration the amount of foam I want to extend to the rear of the fly. These hooks are from The Fly Shop model #3769. The pattern I am going to tie also calls for the front of the foam to be doubled back over itself. I will include an allowance for this in my measurements too. I have also measured the gape of the hook. A general rule of thumb when tying with foam is to make your body width about the same size as the hook gape. See the images for my measurements and the chart below for the specifications. These measurements do not need to be exact and feel free to adjust as you see fit. Also, excuse my illustration skills. I will clean these photos up some day!

Hook Size	Length	Width
#10	1”	.25”
#8	1.125”	.3125”
#6	1.25”	.375”

Step 2.

Now that we have our measurements, we can import the SVG file into our cutting software and begin resizing for our needs. Here, I am using Cricut Design Space version 6.11.113 which is the newest version at the time of writing. From a new canvas, I selected Upload and then selected my SVG file to upload.

As you can see, the default size of the shape is much larger than what we measured. Luckily, this is where the scalability of the SVG file comes into play. We can use the Double Arrow icon to click and drag to resize the shape. If that does not get your shape close to your needed measurements, click on the Lock Icon to make sure the dimensions are not locked to each other and type in your values at the top of the application.

In the next series of photos, you will see that I have zoomed in on my canvas and I also copied and pasted the shape, so I have 3 shapes available. Each one was then resized to match the sizes from my chart above.

Step 3.

Now, I like to prepare my craft foam. In the photo below, I have placed two pieces of craft foam onto my strong grip mat. I then used a brayer to roll the foam. This allows better adhesion to the mat and helps make cleaner cuts. If you are using 3mm craft foam, you will want to repeat the braying process right before you load your mat into the cutting machine.

Also notice that each sheet of foam is 8.5”x5.5” this is important when trying to see how many bodies you can fit into one foam cut.

Step 4. (optional)

This step is optional but helps first time users when spacing out your project to maximize the number of bodies you can cut.

In these photos, you can see that I have created 2 rectangles on my canvas and zoomed out. These rectangles are 8.5”x5.5” just like my sheets of foam. I even colored them brown and green to imitate what my mat looks like. Make sure that you right click on each of these rectangles and choose “Send to back” so that your body shapes are on top. This now gives you a template to use so you know where the boundaries are for your cuts.

Step 5.

Our next step is likely the easiest. You simply copy and paste your body shapes until your templates are full for each color. To make this even easier, you can drag and select multiple body shapes and use the Group feature of the design software to keep multiple shapes together.

When you are finished, your canvas should look something like the photo below.

Notice that you will want to give your shapes a little cushion from all edges and each other. I was not particularly careful when creating this layout. If you are a bit obsessive like I get at times, you can stop using the templates and use the grid lines to line everything up perfectly.

Step 6.

You can now select your template rectangles and delete them as they are no longer needed. Your canvas should now look like the next image.

Step 7.

This step is very important to be sure your project cuts exactly like how you made the layout. Select all images (you may need to zoom out on your canvas to do this) and click on the Attach button in the lower right-hand corner of the application. It is circled in yellow in the image below.

Step 8.

Congratulations! It is time to make your project and cut your foam! Use the Make button in the image above to begin the process.

On the next screen, confirm that your layout looks correct. Be sure that your body patterns are do not extend outside of the measurements for the foam on your mat. Otherwise, you may cut and damage your mat.

Click Continue.

The next screen will prompt you for your material and cutting tool. Be sure you select Craft Foam from the available options. If you do not see Craft Foam, you can search for it on the Browse All Materials link.

You will notice that the Tools section will default to the Deep-point Blade. As I have stated previously that blade will work, but the Knife Blade is much more efficient and accurate. Click on the Edit Tools link to select the Knife Blade if using it. Click Apply and to continue.

Once you have loaded your mat into your cutting machine, you can click on the Go button on the cutting machine itself to start cutting.

You will see that the machine wants to make 2 passes to complete the cut. In my experience, this is not necessary and one single pass works great (even for 3mm foam). In order to stop the machine from starting the second pass, be sure to pause the cut as soon as it finishes the first pass and is repositioning to start the second pass. You can then eject the mat and review your bodies. Your finished project should look like this.

Step 9.

Remove the bodies from the mat and you can begin tying. If you are not ready to tie, I have found that storing the bodies in a plastic bag or compartment box is useful. I typically use a different bag for each size that I cut and label them as such.

Conclusion

The tutorial above may seem a bit daunting at first, but it truly is a simple process once you have completed the steps a time or two. While the initial cost of the die cutting machine and accessories may also seem daunting, I hope that my figures and explanation show that the cost is no more than foam cutters in general. This is especially true if you want to tie many different patterns and in many different sizes. Also, the ability to create your own shape design can be a huge advantage if you are so inclined.

Granted, a good pair of scissors would hardly dent your wallet. However, you can have hundreds of bodies at the ready before you cut a dozen by hand. In this tutorial alone, my project cut nearly 300 bodies of different sizes. How long would it take to cut those by hand or foam cutter? That extra time can be used to tie your flies and even spend more time on the water. Also, you can’t get uniform cuts like these by hand!

In my opinion, the use of SVG files and die cutting machines is the perfect way to save time and money when working with foam. Another advantage I failed to mention earlier (as it doesn’t pertain to fly tying) is that the die cutting machines can be used for many other functions. If you are the crafty type, you can make personalized vinyl car decals, t-shirts, beverage tumblers, coffee mugs, home décor and hundreds of other items.

I hope that you enjoyed this article and that it has helped you in your foam cutting and fly-tying journey. Should you have any comments, questions or concerns, please feel free to reach out to me at any time. As a part of the fly fishing and tying community, I am always willing to help in any way needed. I have also started a Cricut for Fly Tying and Fly Fishing Facebook group to discuss using Cricut and cutting machines in our hobby.

Ron Porreca
ron@fossilfishflyshop.com

DISCLAIMER: All product and company names are trademarks™ or registered® trademarks of their respective holders. Use of them does not imply any affiliation with nor endorsement by them.