Olympos 200 -A B C, irregular grade B and their modification

[DaveG]

Note the large distance between nozzle and nozzle cap in the standard assembly (bottom right photo) and in the assembly with the 771 nozzle and RichPen cap this distance is reduced. Also note the wall thickness of the 771 and Olympos .18/ nozzles.

The gap between nozzle and nozzle cap is the number one reason the NEO for Iwata is so maligned among users and critics of the brush. It has perhaps the smallest gap between the two in the entire industry. What this does is makes paint reduction the most important factor in getting consistent results. The brush is capable of very fine detail, and soft atomization - yet many people pan it (more likely because they perceive it as being made in China). It is not a brush you can turn air pressure up and make up for poorly reduced paints, as you can with many other brushes... only so much air will fit through that space between nozzle and cap.

That gap is a key area of consideration in actually tuning an airbrush. The relationship between the air cap, nozzle and needle are the "whole enchilada" in terms of performance from any given brush. The rest of the brush is just a handle

 

[Fran Rioja]

Photographs taken under a microscope. Visual comparative characterization of the interaction between nozzle cup and nozzle of different configurations on Olympos 200 airbrushes.

Yesterday I mounted a 771 nozzle with a 112b cap after reading Dave's reply and the result is very good, I'm going to leave it at that and I have already ordered 2 more 112b caps for the 200C and the 200A.

 

[RK Ink and Focus]

The gap between nozzle and nozzle cap is the number one reason the NEO for Iwata is so maligned among users and critics of the brush. It has perhaps the smallest gap between the two in the entire industry. What this does is makes paint reduction the most important factor in getting consistent results. The brush is capable of very fine detail, and soft atomization - yet many people pan it (more likely because they perceive it as being made in China). It is not a brush you can turn air pressure up and make up for poorly reduced paints, as you can with many other brushes... only so much air will fit through that space between nozzle and cap.

That gap is a key area of consideration in actually tuning an airbrush. The relationship between the air cap, nozzle and needle are the "whole enchilada" in terms of performance from any given brush. The rest of the brush is just a handle

I could not agree more with this about the neo. I had a neo bcn for a while and with the 0.5mm needle and nozzle set up it was very capable, it could pull fine lines and they were silky smooth which I guess is from the atomisation you mention.

 

[Mitya Ka]

The gap between nozzle and nozzle cap is the number one reason the NEO for Iwata is so maligned among users and critics of the brush. It has perhaps the smallest gap between the two in the entire industry. What this does is makes paint reduction the most important factor in getting consistent results. The brush is capable of very fine detail, and soft atomization - yet many people pan it (more likely because they perceive it as being made in China). It is not a brush you can turn air pressure up and make up for poorly reduced paints, as you can with many other brushes... only so much air will fit through that space between nozzle and cap.

That gap is a key area of consideration in actually tuning an airbrush. The relationship between the air cap, nozzle and needle are the "whole enchilada" in terms of performance from any given brush. The rest of the brush is just a handle

I don't have a Neo, if you have a picture of the nozzle and nozzle cup contact, it would be interesting to see. I totally agree that these parts: needle, nozzle and nozzle cap, their dimensions, tolerances and interactions play a key role in the performance of the brush (you could say it is the heart of the brush ) and in the consistency and atomisation of the paint at a certain pressure. Regarding the nozzle exit orifice of some companies, my rough measurements yielded the following results:
Olympos .18 = .28-.30 mm
RichPen 112A/B .2 = .25 mm
RichPen 113/C .3 = .35 mm
Creos 771 .18 = .35 mm.
I don't have the equipment to measure inside diameters, so the results are approximate. You Dave may have the exact numbers
Everyone's nozzle inner taper is different, and nozzle wall thicknesses are different too. I would be interested to study the inner nozzle taper, probably needing to rub jewellery wax into them in some way to get an impression. The nozzle cap would be easier to do this trick with.

 

[Mitya Ka]

Yesterday I mounted a 771 nozzle with a 112b cap after reading Dave's reply and the result is very good, I'm going to leave it at that and I have already ordered 2 more 112b caps for the 200C and the 200A.

The 200 brush with the 771 nozzle and the 112A/B nozzle сup is my favorite at the moment. From the 200 series brushes.

 

[RK Ink and Focus]

I don't have a Neo, if you have a picture of the nozzle and nozzle cup contact, it would be interesting to see. I totally agree that these parts: needle, nozzle and nozzle cap, their dimensions, tolerances and interactions play a key role in the performance of the brush (you could say it is the heart of the brush ) and in the consistency and atomisation of the paint at a certain pressure. Regarding the nozzle exit orifice of some companies, my rough measurements yielded the following results:
Olympos .18 = .28-.30 mm
RichPen 112A/B .2 = .25 mm
RichPen 113/C .3 = .35 mm
Creos 771 .18 = .35 mm.
I don't have the equipment to measure inside diameters, so the results are approximate. You Dave may have the exact numbers
Everyone's nozzle inner taper is different, and nozzle wall thicknesses are different too. I would be interested to study the inner nozzle taper, probably needing to rub jewellery wax into them in some way to get an impression. The nozzle cap would be easier to do this trick with.

I would be interested to see the results of the nozzle and cap taper investigation if you ever do it. It would also be interesting to see the different flow from the different nozzles, caps, needles and body air exit apertures, like you see in the wind tunnels when they are running aero on a car.

Ismael is the camera guy, I wonder if we can talk him into getting sone ultra slow motion tech

 

[DaveG]

It can be interesting to watch (sorry, no video).

 

[Mitya Ka]

It can be interesting to watch (sorry, no video).
View attachment 88158

Dave thanks for sharing. Judging from the photo this distance is really short.

 

[Mitya Ka]

For a long time I had the idea of creating a nozzle cup for the Olympos 200. I've been playing around with the lathe a bit.

 

[Mitya Ka]

Nozzle cup from 200A was bored to fit M4x0.5 thread. A guide with the same thread was machined, the depth of which is adjusted with a nut.

 

[Mitya Ka]

When turning these parts, I didn’t particularly hope to get good results since my lathe is homemade and does not currently have high accuracy. I needed my first experience turning these parts. This type of nozzle cup was made so that the depth of the nozzle could be adjusted relative to the nozzle cup. The results were mediocre, but the experience was wonderful.

 

[Mitya Ka]

When turning these parts, I didn’t particularly hope to get good results since my lathe is homemade and does not currently have high accuracy. I needed my first experience turning these parts. This type of nozzle cup was made so that the depth of the nozzle could be adjusted relative to the nozzle cup. The results were mediocre, but the experience was wonderful.

Perhaps the results will be better when I get an accurate ER11 collet chuck

 

[DaveG]

When I have multiple threaded parts that have to remain concentric, I will usually make holding fixtures I can mount in a 4 jaw independent chuck so that I can accurately position them for machining. Collet chucks are very nice for doing multiple parts with easy set up.

 

[Mitya Ka]

When I have multiple threaded parts that have to remain concentric, I will usually make holding fixtures I can mount in a 4 jaw independent chuck so that

Do you make a cylindrical sleeve with a horizontal slit that crimps the work piece evenly?

 

[DaveG]

Do you make a cylindrical sleeve with a horizontal slit that crimps the work piece evenly?

I generally make threaded parts to accept the part I want to work on leaving a section of turned rod that I can gauge off of. I will take some pictures tomorrow with a few of the setups I might use for working on something like you are doing.

 

[Mitya Ka]

I generally make threaded parts to accept the part I want to work on leaving a section of turned rod that I can gauge off of. I will take some pictures tomorrow with a few of the setups I might use for working on something like you are doing.

Oh, cool, thanks Dave

 

[DaveG]

Here are a few examples - I use a collet chuck to hold the raw material to start each piece. For my holding fixtures I try to do all the hole drilling and threading at one time, without removing the work piece from the chuck. If you are single point threading on the lathe, then it is no issue also cutting reference flat on the piece for locating later with an indicator. If you are using a die stock or tap, it is a bit harder - as you will need to make an opposing threaded piece that can be threaded on or in to use for locating later. If at all possible, it is easier to do single point threading when trying to keep things concentric.

Here for a nozzle (or air) cap - First steps on this are to do the inside. I drill to depth and contour the inside of the nozzle surround, thread the ID to fit the brush body threads, and drill the exit bore. Doing all of these steps without moving the piece greatly increases the chances of keeping concentricity. The OD of this piece during this stage would have been full diameter of the raw material. I generally take a skimming cut of the OD while the piece is still help to make it concentric with the ID, too.




The holding fixture is inserted into the four jaw independent lathe chuck. An indicator is set up with the tip on a pre-cut reference surface on the fixture. This area needs to be cut at the same time the fixturing piece is held for the threading operation - so that it is 100% concentric with the threads. The jaws are loosened and tightened until I get as little movement as possible on the indicator needle when rotating the piece.


The needle cap threads can now be cut in a manner that will keep them concentric with the center bore of the nozzle cap. This method is more accurate than a collet chuck, as there will always be some runout associated with the collets. By using an indicator to center the work in the 4 jaw, you cut the runout at least in half if you take your time setting up.

 

[Fran Rioja]

Now that I see the photos, I have to ask you: have you ever thought about making a nozzle cap so that Holbein Y series airbrushes can use a shorter and easier to find nozzle?

 

[DaveG]

Now that I see the photos, I have to ask you: have you ever thought about making a nozzle cap so that Holbein Y series airbrushes can use a shorter and easier to find nozzle?

hehehe, you are not the first to ask the question - I am pretty sure there would be a need to also make a head base to accept a nozzle with a more common thread size.

 

[RK Ink and Focus]

I am enjoying reading this thread, I like the enthusiasm to make and modify parts. Being in engineering (quite small stuff) it makes me want to have a go!