Which spray cap?

Spray Paint Caps Tested: From Skinny Lines to Ultra-Fat Coverage

If you’ve ever stood in front of a wall wondering which spray paint cap will actually give you the line you want, you’ll know there’s a surprising amount of difference between them. Some produce razor-thin lines, some are better for stencils, some give you huge amounts of paint, and a few are simply not worth buying.

In my latest video, I tested a selection of spray paint caps from some of the skinniest through to the biggest, using MTN 94 for most of the testing so the comparison stayed as consistent as possible. The aim was simple: find out which caps are genuinely useful—and which ones you can save your money on.

Starting Skinny: Skinny Pro

The Skinny Pro remains one of my favourites. It originally came on MTN Alien cans, and when it appeared it felt like a genuine game changer. Using one can feel almost like drawing with a pencil.

It produces an extremely skinny, relatively clean line and works particularly well with lower-pressure cans such as MTN 94 and Flame. If fine detail is your priority, this is one of the first caps I’d try.

The Kak cap is another strong option for skinny lines and feels quite similar. If a Skinny Pro doesn't suit the particular paint you're using, it’s worth experimenting with one of these alternatives.

Montana Levels: Mixed Results

I also worked through the Montana level caps, and the results were mixed.

Some of the smaller levels offer decent control and could work well as skinny caps for pieces, although the thinnest can be too skinny for that job. As the levels get larger, you naturally get thicker lines, but I found some of the spray patterns inconsistent.

That highlights something important about spray caps: the cap and the paint have to work together. A cap that performs badly on MTN 94 might behave completely differently on Montana Gold, Flame, Loop, Cobra or another paint.

The Best Caps for Stencils

For stencil work, I actually like a slightly fuzzy spray pattern rather than an ultra-sharp line.

One standout is the grey-body cap with the blue dot. It produces something almost like a small wide spray, making it particularly useful for stencil work.

Some of the older medium-skinny caps are also excellent all-rounders. They're useful for stencils, small fades and controlled lines without being so skinny that they become awkward for general painting.

Calligraphy Caps Are Surprisingly Versatile

The calligraphy caps are some of the more interesting options in the test.

Instead of producing a conventional round spray, they create a straight or elongated pattern. That means you can use the same cap for filling areas and then rotate it to produce finer detail.

If you struggle to get the results you want from conventional skinny caps, these are absolutely worth trying. I particularly like the red calligraphy cap, as its wider side gives you a larger fat line while still allowing good detail.

Needle Caps for Effects

Needle caps aren't something I'd necessarily reach for to paint an entire piece, but they are extremely useful for effects.

They're particularly good for rust effects, props and straight lines on shutters. Of the different versions, I favour the red needle because its larger pipe seems to make it less prone to clogging.

My Favourite: Hardcore

My favourite overall is the Hardcore cap.

Unfortunately, it appears to be discontinued for the moment, but hopefully it returns. On a low-pressure can, it is extremely easy to control and can produce both thin and thick lines.

Of all the caps I've used, I find it one of the biggest and most versatile. It works particularly well with MTN 94, where I can achieve skinny lines that I struggle to reproduce with higher-pressure paints.

The Astro is a good alternative, although in my test it seemed to require slightly more pressure from my finger. The orange Hardcore felt as though it provided more volume with less pressure, which is exactly the combination I like when painting.

Why I Prefer Ultra-Fat Caps

One of the interesting conclusions from this test is that I often prefer an ultra-fat cap to a conventional fat cap.

Why?

Because ultra-fat caps can provide high output at lower pressure. That can actually give you more control, not less. With the right paint and technique, you can still pull surprisingly skinny lines from a very wide cap.

Then, of course, there are things like Big Daddy and the Flame Booster. These aren't exactly subtle—but they're a lot of fun. Just be warned: the really big caps can empty a can incredibly quickly, and all that gas passing through the nozzle can make your finger seriously cold.

So, Which Spray Paint Caps Do I Recommend?

After testing everything, my shortlist is fairly simple. For the skinniest lines, I'd go with the Skinny Pro, with Kak, Universal or Banana-style caps as alternatives depending on your preferred paint. For more unusual controlled lines, the red calligraphy cap is one of my favourites, with the white calligraphy version offering a smaller option.

For general versatility, Hardcore is still my favourite, with Astro as a strong alternative. And for effects, I'd keep a red needle cap around.

The biggest lesson, though, is that there isn't really one perfect cap.

Choose the paint you like first, then find the cap that works best with it. The same cap can behave very differently depending on the pressure and characteristics of the can underneath it.

If you've got a favourite cap—or one you think I've completely underrated—let me know.

Watch the video: