Learn different ways to make decals for your rc car boat or plane, especially if you want to recreate vintage decals for a restoration.
Part 1 – Artwork and a bit of colour theory
Part 2 – Different ways to make decals
Part 2A – Vinyl Cutting Your Decals
This is a continuation of my series of articles on making your own decals. I was going to put 4 different methods in one article, but have now expanded that to make them an article each. In this article I will detail how you can vinyl cut your own decals. This is one of my preferred methods as the decals are durable and you can get really good results for most designs. To do this though you will need to own or have access to a vinyl cutter.
Vinyl cutters are essentially a plotter with a little knife in the end instead of a pen. Artwork needs to be in vector format, although some dedicated software programs will convert bitmaps to vector for cutting. Prices range from at least a couple of hundred dollars secondhand to around $600 for a new one at cheaper end of the market and then upwards to as high as $2000 or more for a top of the line one. These are Australian prices, I suspect in the US prices are likely to be cheaper, UK and Europe I have no idea.
The supplied software on the cheaper ones I have found a little trying to setup, but they do work.
Below is a picture of my vinyl cutter, its a Roland CX-24 and its around 14 yrs old. It connects to a pc via a parallel port cable, and I cut from a design program called coreldraw X3, which is about 4 yrs old. The pc runs XP and is around 6yrs old, so you don't need the latest and greatest.
To cut you will need the following tools and materials:
- application or positional tape – this transfers the cut vinyl to the where you want to place it, you can get away with a low tack masking tape as well.
- pen knife or scalpel – used to weed out unwanted vinyl
- and a vinyl cutter connected to a pc
Types of vinyl
vinyl is usually pvc based and there are basically 3 types of vinyl:
- and specialty
Calendared vinyl is generally to short term use ( 6 months to 2 years) or mid term vinyl ( around 3 to 5 years) and cast is a long term vinyl, usually 7 years plus. The years are the outdoor expected lifespan, on a vertical surface that gets about 50% of the sunshine during the day in a moderate climate. Vinyl is also rated by how conformable it is. Whether is flat surface only, simple curves or complex curves.
Calendered is the cheapest and is made in either monomeric or polymeric form. Cast is the best, but also the dearest and specialty is vinyl like reflective, chrome metallics etc.
I would avoid monomeric calendared vinyl if possible. It it really only a short term vinyl and tends to shrink quite a lot overtime, as much as 5 to 8%. It seems to me a lot of repo decals are make from this type of vinyl. The glue is usually sub-optimal as its designed for short term use and ease of removal. Cheaper vinyl also tends to be thicker and won't stretch that well, if at all.
Polymeric calendared vinyl is a good standard vinyl though, and will be quite adequate for most jobs. It won't shrink at much as monomeric vinyl and the glues are better. There is a quite a large range of colours and brands available. It will also have some stretch, so you can warm the vinyl and pull it around corners etc, but nothing with too much curves.
Cast vinyl is the best, and it what is used for car wraps. It is highly conformable and when the glue is activated it will adhere for a long time, yet is not too hard to remove. It is also the most expensive to buy though. This vinyl can also quite often come with air channels in the glue, which makes removing bubbles as easy as just rubbing them out.
Cast and polymeric vinyls also tend to be easier to cut and weed. This can make a difference to your stress levels when you are cutting fine text!
Specialty vinyls come in a range of colours like chrome, gold, metallics, lustre colours etc, plus there are a number of patterns like polycarbonate, gold leaf etc. The only real downside to a lot of specialty colours is that they will not stretch at all, so application on curves can be an issue. Removal can also be problematic too, as many of these vinyls simply fragment badly when you try to remove them.
Why I like vinyl
There is a bit of setup and preparation to using vinyl, but there are two things I like about vinyl that makes it my preference. The range of colours and the durability. The colours are glossy and usually very rich in colour and there is a large variety of colours patterns available. Patterns can also be made by overlaying vinyl to build up designs. The only real downside is colour matching to a specific colour would be problematic, as would matt colours. As for coloured vinyl, the whole vinyl is the colour, so this makes scratches less noticeable. Plus vinyl is water resistance and suitable for outdoor use.
You can also buy masking vinyl for spray painting. You can use normal vinyl for masking, but test your paints first, as some of the solvents in paints can dissolve the vinyl.
This is a picture of my Audi I started to restore. Most of the decals being done in vinyl, the rest I digitally printed onto vinyl (that'll be the next article).
There are 3 ways that I can think of that you source some vinyl.
- through ebay, although be aware of what you are buying.
- Go to a sign supplier, they'll sell it by the metre though.
- go to the local sign shop and ask for offcuts, they are bound to have plenty, although you might be limited in choice.
Don't buy vinyl that is older than about 2 yrs though. The vinyl and glue have a shelf life of up to 2 yrs, approaching this time the glues go off, and it won't stick properly, the vinyl can start to harden.
The Vinyl Cutter
All vinyl cutters are basically the same in how they operate, with prices reflecting the quality of the components. But basically all vinyl cutters will:
- have a holder for a small rotating knife, the moves along the cutter.
- have 2 or more pinch rollers for securing the vinyl, and one long roller underneath that is driven by a motor, that will move the vinyl in and out.
- will have a cutting strip which the blade runs on top off. This provides the backing surface for which the blades cut along.
will have a control panel where you can adjust the speed and pressure of the cuts and the offset of the knife.
A picture of the blade holder
here you can see the holder installed in the vinyl cutter, with the blade just sticking out.
Settings – To cut well, spend time on the setup
To cut well, you must have a sharp blade, your cutting strip must be in good condition and the blade must be set properly.
There are 3 types of blades, 30, 45 and 60 blades. These refer to the angle of the blades and are needed for different types of vinyl. The higher angles are sharper, but will dull quicker, with 45 usually a standard. My local supplier sells blades for around $45 AUD each, but as I am a cheap skate, I buy from China, the blades usually end up costing around $1.50 each if I buy in bulk. I run a sign shop and cut regularly and I barely notice the difference in quality.
30 – will last longer, but not recommended for fine work or thicker materials
45 – standard blade used for most cutting
60 – use for the thicker vinyls like chrome and reflective, plus also fine text, anything below about 15 mm high.
Each vinyl is slightly different, so make sure the cut is deep enough to make the vinyl easy to pick or 'weed', but not so deep that there is a cut mark left in the underlying paper backing material. In fact there should barely be a mark or score in the vinyl. This is important because if the cut is not deep enough, you vinyl won't weed easily, and if its too deep, it will wear out the blade quickly, and can making weeding and placing harder too.
Many vinyl cutters have a test cut function, mine is a square inside a circle (a common test). I check that the square is cut properly (corners are proper), I can remove the outside with ease, and that the backing paper hasn't been cut into.
In this test cut, the corners are slightly rounded. This can be caused by the cutting offset being incorrect (I would try a lower value first), or in my case its likely the blade is a little too far out and getting blunt.
Insert pic vinyl_cut_rounded_corners-01.jpg
Adjusting your cutter
There are 4 things that you need to make sure is right, and usually these are adjusted on a cutter. You would need to refer the the specific manual of the cutter to this:
- how fast it cuts.
- the pressure of the knife
- the offset of the blade (this will affect things like sharp corners)
- the amount the blade sticks out from the holder
Usually the speed of cutting, the offset and the amount of blade that is showing is adjusted only once and its the pressure of the blade onto the vinyl that you will change regularly. The basics are, cut as fast as you can, with as little pressure as you can. I rarely change the offset, so go with what its set at, and I have the blade sticking out a little as I can.
When I cut I usually don't cut too much lower than 4 or 5 mm high for text. You can try smaller, but it does get hard to weed, and sometimes it won't cut properly.
I usually weed out delicate items first
Apply application tape (which is just a low tac tape, you can use masking tape if you have to).
This will now hold all the elements together so the sticker can be moved to where you want to place it.
If you have problems peeling up the vinyl with the application tape, it could be that the cutter was cutting too deep and scoring the backing paper.
Place your sticker in position. I usually only push down on one side, then squeege across.
When removing the application tape, don't pull it up, but pull it 180 degrees backward, this makes it less likely for some of it to come off.
All vinyl cutters will have an origin that you have to set after you load up the vinyl sheet. This is the point where the cutter starts cutting from and references 0,0 point. A benefit of this is if your first cut is unsuccessful, and you haven't unloaded the material, you can tell the machine to re-cut it and it will recut the print exactly over a previous cut.
Some people wet decals before they apply, as it helps to position them. You can do this too with vinyl cut lettering, but if you use application tape, you have to be quick as it weakens quickly.
If your cut is very fine and difficult to weed. Apply your application tape first, peel off the backing sheet and weed it from the back. Its slower, but the application tape will hold the fine details in place.
To help weed small items, I place a box around the outside, so it makes it easier to locate and pull out the vinyl. Then you can place the application tape to transfer the decal.
Well, thats about it, please leave any comments or questions. My next article will be on digitally printed stickers,
Written by TB member yogi-bear