Changing needle size on Iwata HP-CS

I’ve been thinking about trying the .5mm needle instead of the standard .35mm in my HP-CS and was wondering if I need to change the nozzle and nozzle cap to use the larger needle? From what I can see on the Iwata website it looks like they make parts for the different sizes, but I wasn’t sure if I needed to change other parts to use the .5mm. Is it recommended or can I use the nozzle from the .35mm with .5mm needle?

Also, it’s been recommended by some people who spray with the Paasche to use a #3 needle when spraying acrylics. What would an Iwata #3 needle be? I was told a medium size, but have no clue what that means in regards to .35mm or .5mm. I was looking at those Paasche needles and they look way different then the long Iwata needles. Thoughts?

Finally, where do people like to shop online for Iwata parts?

Thanks,
Burt

If your HP-CS is in very good condition and you have the original packing materials, you can sell the CS on Ebay and purchase a new Iwata Revolution HP-CR airbrush with the 0.5 mm needle/nozzle. That way, you can end up making a few dollars instead of spending more.

The 0.3 mm needle/nozzle can do everything the 0.5 mm will do. But not the other way around. Why would you want to change it anyway. Just curious.

The Iwata is NOT like the Aztek or other lesser design. You don’t need to change nozzle on them. It can paint from hair line to over an inch wide line using the same nozzle.

I buy Iwata replacement parts at local store, perferrably Hobby Lobby using their 40% off coupon. The shipping usually makes internet order too expensive compared to local purchase.

Burt,

You should be able to paint anything imaginable in modeling with your current airbrush.

Don’t let the hype of needle diameter steer you in a direction that you think may help you paint better as it’s a fantasy. Needle taper is the determining factor for line width, not diameter!

Now, with that in mind let me add that some of the finer tapered needles may or may not work well for modeling paints. People think that the higher-end the airbrush, the finer the line, but that is simply not true. The diameter of needles and the faster taper of them apply to certain mediums only, and that means using paints that we do not use such as watercolors and urethanes.

With a Badger 100LG, Badger Renegade, Iwata HP-CS, or any other high-quality airbrush, with practice, you can paint anything you want to on models regardless of needle diameter…period!

Now if you are having problems painting with the needle and tip size you have because of clogging and so forth, then the needle size could be too small but I am not sure as I don’t use that particular airbrush. I know many times that modelers will have problems with a #1 needle and tip in Badger and Paasche airbrushes and switching to a #3 is better all around.

Is that possibly what you are experiencing?

Hey Guys,

Yeah I was experiencing some clumps when shooting Polly Scale and so someone mentioned spraying with a medium sized needle. Honestly, I don’t want to change anything from what I have now. I love this Iwata model and how easy it is to clean up. The only reason I wanted to go for a bigger needle was because it might help with my issues in spraying Polly acrylics without it gumming up. Anyways, I plan on keeping my HP-CS and will continue to shoot with the .35mm, I just thought I would try the other size too.

Thanks

Hi Burt,

I’m not sure what you mean by “clumps” but if you mean you’re getting irregular splotches or “spitting” or spattering of paint over the regular spray pattern, it suggests that you may not be thinning your paint sufficiently. Frequent clogging of your airbrush also points to this being a possible issue.

However, I’m not familiar with PS paints and I’m basing this on my experience with Tamiya paints, which can be thinned quite extensively.

I don’t use Polly Scale and cannot guess the source of the problem. However, the 0.3 mm needle with a gentler taper should atomize better than the 0.5 mm. This suggestion does not make sense to me.

How did you thin the Polly Scale? Is it possible that it dries too fast? Are the clumps solid or just a splatter of wet paint?

Don’t forget that you have the ”slots” in the sides of the rear of the brush, whose whole purpose is to clear stoppages. Point the brush at your test area, push straight down on the plunger(don’t pull back), and while pressing down, grab the needle nut from both sides, and pull fully back to clear.

This is a zombie post from 9 years ago! OOOOH Scary!!

…and if not for your post, I would have gotten sucked into it. Even though there is not one familiar name in the whole thread, except yours, 66. That’s usually my clue.

I missed one! Lesson to self, it happens.