SNC Basics - A step by step guide to Test Cuts

Draft post - quick and dirty for an fb group where a poor user has cut a ginormous hole in their mat (hopefully now taped up from the back and useable again).

Oh dear! you've cut a big hole in your mat, or your cuts aren't clean and messing up the surface of your material. arghhhh you are so frustrated, the machine looked so easy on the TV! and you can't get it to work and want to throw it out of the window for all the wasted time and money.
Is it your fault? why won't it work?

Well, have you done proper test cuts, do you understand the relationship between speed, blade depth and pressure? Because yes, some materials are just horrible and won't cut well, but usually cutting problems can be solved by using the right settings. The settings are NOT arbitrary, it's NOT an arcane mystery. The settings are logical and can be created to be pretty much exactly right if you know how and why they behave how they do.

I did a post on test cuts ages ago. This is complimentary to that and is a step by step 'how to do test cuts' the long way round.
Let's learn to do test cuts!

This is the way I do it with every NEW material, say a different weight of card or vinyl or fabric. I do maybe 10-15 test cuts and write the final settings down for future reference.

Key knowledge - low speed gives you chance to press pause and also the machine time to get around intricate shapes nicely. Blade depth is about how thick the material is. Pressure is about the density and how hard the blade needs to press down. Imagine you are cutting a carrot, you need to press quite hard, but then imagine you are cutting a strawberry, you need way less pressure. however both of them at their thickest part are the same diameter around. So that's the three elements:

Here's how to do successful test cuts every time.

1. speed on 1. this means you only have to worry about depth and pressure settings. always cut on 1 at first and always for setting test cuts on new materials.

2. pressure at -9' yes minus 9. this is the very lowest setting.

3. blade. make sure no debris in the holder and that the blade is seated right. do NOT use the back of the spatula to remove a blade, this is only for a broken blade. Use tweezers and pull, the magnet that holds it in will give way. Don't drop your blade. Never leave your blade in the machine when switching on or off as it can break the tip (unusual but happens).

also with blade - the blade holder has a sticker, which ought to be placed in exactly the same place for every holder but it isn't. I'll explain below why this matters for following suggested settings just bear this in mind.

Turn the blade holder down to zero, then up to as far as it will go past 12. some only go a tiny bit past 12, some go way past almost as far as the edge of the sticker. Just be aware how far yours goes for now. Then turn blade back to half way between zero and 1. and with the machine already switched on, put it carefully into the machine vertically so you don't knock the tip of the blade (I'm in a wheelchair and forever putting it in sideways and buggering my blades!)

4. Put your chosen material, say cardstock you'd use to make an actual card with, the one you fold in half and decorate. Let's say it's about 300gsm. Put it at the bottom of the mat, NOT the top where the blade is if it's smaller than 12x12".

5. click the pattern button. at the top you see test cut icon. click it, and pick the square one. click ok.

6. do a background scan (read the manual for how) and move the test cut down to the bottom of the mat (this is so that you can see what's happening more easily as it's away from the blade area).

7. with settings of speed on 1, pressure -9, blade 0.5 do a test cut. this will barely scratch the surface.

8. move the test cut to a new place on the material, change the blade to 1.0 and do another test cut.

9. repeat the moving and adjusting by 0.5 or 1.0 setting until the cut begins to look good - a good cut is a nice clean slice, that just scratches the surface of the mat, nothing more, leaving a faint outline, and the test cut just pops out.

If you find it hard to move the test cut, look in the Manual for screen callibration. If you find the test cut is leaving a little tail where the cut begins and ends, look in the Manual for doing a scanning/cutting adjustment.

10. eventually you'll get to the stage where the cut is pretty good but maybe isn't quite right on one corner. Let's say this is at 5. if you put it up to 5.5 or 6.0, it still misses a bit, but makes a deeper scoring in the mat. that's how you know to stop at 5.

11. You then go to settings when blade is at 5, and do another test cut but pressure at -2. see if that cuts perfectly or not. Repeat test cuts changing ONLY the pressure til you get to where it cuts perfectly (probably at around 0 or 1 pressure). DO NOT skip the steps of doing one test cut per setting at this stage. You are LEARNING to do test cuts and learning how blade depth and pressure interact. When you've done it lots, you can maybe estimate, oh i think this will be blade 5 and pressure 0, so you can start the test cut at 4 with pressure at -2 and just do a few. for this learning curve, do the full thing then you'll understand and be able to see more quickly in future what the likely settings are.

12. so let's say you have now done incremental test cuts with the pressure and it has indeed come out at blade 5 and pressure 0. Keep the test cut shape on the mat. By this stage you'll have done maybe 10-15 test cuts. they're only tiny and remember you can do background scan each time to reduce wastage of material.

13. Write those settings down along with a note of the exact material you were cutting. In a little book. Then when you cut that material again you can just set the blade to 5 and 0 and do a single test cut to check they still work (blades age and so do mats) and then go ahead on your actual project.

14. Now go back to pattern and pick a standard square and a standard circle at whatever standard size they come out at. do a background scan so you can avoid all the holes you've already made. Cut both those shapes. This extra step is a good idea with a new material because often the test cut looks perfect, but when you cut a bigger shape, nope it's not. that's why you keep the test cut on the mat, so you can adjust the settings after cutting the standard shapes.

when you have any shapes + the test cut on the mat, the machien will cut the test cut then stop. it will wait for you to decide if the test cut is good or not. If it isn'tyou click cancel, and mvoe the test cut and redo. if it's fine you just press the go button (cool huh!). Remember if it all starts going wrong you have a pause button!

15. assuming the standard shapes cut out perfectly, you are now good to go to be absolutely confident that what you are wanting to cut out, no matter how intricate, assumign the cut file is not messed up, will cut perfectly with NO cut through mat and NOT messed up cuts.

16. Once you fiddle around getting your project on the mat screen and your material on the mat for the actual project ALWAYS just check the blade depth speed and pressure against what you wrote int eh book!!!! we all forget and cut through our mats sometimes!

here's a blog post on troubleshooting and how to know what a good cut looks like.http://goblinfblog.blogspot.com/2016/11/scanncut-basics-4c-test-cuts-are-your_25.html

Seriously, if you dont' spend the time on test cuts and understanding how they work you will never ever master the machine and will have a lot of wasted time and energy and materials.

Finally. There are suggested settings, brother have online in the brother support centre, and a blog by gentleman's crafter has some you download as a pdf. These are NOT where you start and set your settings for test cuts. These are just guides to show you where the average blade ends up. So if the suggested settings say blade 5 and pressure 0, I personally would start at blade 3.5 or 4.0 and pressure -2. Why so far away? Well because I do that whole thing above EVERY TIME I haven't used the machine for a while. and because I've done it, I know that one of my blade holders goes way past 12 on the sticker. And the other blade holder goes only just past 12. By comparing test cuts on identical material to the suggested settings, I know that the difference between those two is about ONE blade setting in depth. So, if I choose to follow recommended settings I start at least ONE AND A HALF or TWO settings below suggested. This means I do maybe 4 test cuts, but it also means I'm less likely to cut through my mat!

There are videos online about how if your sticker is way off an official suggested setting, you can carefully peel off the sticker and restick it so that it matches the suggested settings. However, if you do that, fine, but do NOT do it wihtout matching it to your actual blade. where your blade is test cut and set at 5 to cut perfectly for a suggested setting of 5 and use that to line it up. then everything else should follow. however, there's manufacturing differences in blades and if you move the sticker too far, you risk having to do it again when you have a new blade. cos it could be a combination of blade manufacturing tolerances and holder sticker misplacement.

therefore, rather than move my sticker, I've chosen to do more test cuts by starting lower than suggested, because I've found this helps when dealing with tricky materials or tricky cut files.

Finally, there's some leeway. a blade depth of 4 and pressure of 2 might make exactly the same cut as a blade depth of 5 and a pressure of -1. that's because a higher pressure pushes the blade down more so it effectively reaches down towards the mat further. However, if you have coated card stock or maybe vinyl which is stretchy, the more pressure you have the more likely it is the top of the material will be scuffed or pulled if the pressure is compensating for the blade depth not quite being enough. So this is why sometimes people who cut everything on one setting, find some things cut well and others badly when there seems to be no reason. there is a reason! trickier materials need a more accurate setting!

Yes all that seems very complicated adn longwinded. But if you do it regularly at first, in full, then just go a bit below suggested settings thereafter, you'll have done the learning curve quite painlessly and will have cutting success for ever!