by: Paul H [ ]
This is the fourth in a series of articles where I will try to provide useful data for the prospective airbrush purchaser. I will again cover key features, evaluate performance using modeling paints and materials and describe how that performance was measured. I will continue to use standardized products and methods in order to provide situations that can be duplicated by any individual who chooses to do so. From there they can decide what value to place on the information provided. The inclusion of the materials and methodology I include is not intended to irritate, but to provide a frame of reference for anyone who reads any one of these articles individually without having to read the entire series.
I have used airbrushes in modeling for about 30 years and I have no affiliation whatsoever with any airbrush, paint or model company. Most of the brushes I evaluate will be brushes that I bought and paid for out of my own pocket. None were received for review or were bought at a discounted rate from a manufacturer for consideration. The ones I don’t personally own, were borrowed from a friend who tolerates my curiosity.
I will continue to use two readily available modeling paints using thinners manufactured by the companies who produce and sell the paint. This is not an attempt to call into question the suitability of various thinners others use and there will undoubtedly be people who can achieve better results with their preferred thinner, but these products provide control factors which provide stable and repeatable methods. The paints used will be Tamiya and Vallejo Model Air. They are readily available via the internet even if they are not in your local hobby shop.
Paints will be applied to sheet styrene using the pressures where best performance for the brush in use is achieved for stated thinning ratios. Lines and spray patterns will be measured using digital calipers so very slight differences will show in metric conversions as they will be taken from the caliper and not from direct conversion of a number. In my opinion, .010” gives a more concrete measurement than .01034” so I won’t go past 3 decimal places. The compressor I use will always have an adjustable and regulated air supply with moisture traps in line between the compressor and the airbrush.
Below are the criteria that I intend to use for all airbrushes I evaluate:
Brand, action type, feed type, trigger type, nozzle type, nozzle size, air fitting size, cup volume, length, diameter and price
Special Features & Accessories:
i.e. MAC valve, solvent proof seals, preset handle, lids, wrenches, water traps, etc.
Atomization, ergonomics, fit, finish, pattern size, smoothness of action, ease of cleaning, parts availability
Badger Krome Details and Features
The Badger Krome is one of Badger’s Renegade series of airbrushes. They are usually associated with professional airbrush artists who use them as rugged, high reliability tools in their businesses. These airbrushes have a substantial following in the custom automotive and motorcycle paint crowds, and are aimed at producing fine detail using the acrylics and urethanes common in those areas. Naturally, modelers saw an opportunity and adopted the brushes quickly, but they were never truly optimized for that purpose. The Krome however, was specifically created to provide certain features like a lighter trigger pull, adjustable and repeatable preset handle and the silver finish preferred by some modelers. It is a double action, internal mix, gravity feed design which uses the standard top mounted trigger setup. External surfaces are covered in a bright chrome finish that is very nicely done. The brush uses the standard Badger airline fitting which will not make users of brushes with the 1/8” air fittings like Iwata, Grex, Tamiya or Harder & Steenbeck brushes happy, but a Badger air fitting for 1/8” adapter usually comes with the brush so there is no need to procure a new hose. The Krome also features a 1/3 oz. color cup, an adjustable trigger assembly, a cutaway handle with a resettable dial indicator on the preset function and an adjustable solvent proof needle bearing. The common street price for the brush is from $110-$140 US dollars. Spares are readily available in the United States and in Europe via the internet. Availability in other countries may be somewhat more of a challenge, but I have never heard of anyone saying that parts for Badger brushes were unattainable once the model had been available for a few months.
The Krome airbrush utilizes a small .21 mm self-centering type nozzle made of a tough alloy and held in place by a hold-down ring which features six air passages versus the more standard one or three-hole patterns used by other companies. The needle is also made of a tough alloy and is very finely polished. The Krome is roughly 6.5” (16.5 cm) long with a .428” (10.9 mm) diameter main body. It also includes a .33 needle and nozzle as another option.
I have provided a picture of the standard breakdown of the brush. Pic 2
The mechanical fit of all components used in the Krome is extremely good. Threaded surfaces are in natural brass and fit together very precisely. The finishing of most internal parts is chrome and polished to a high level. The exterior of the brush and the interior or the color cup has a nice chrome finish. The exterior finish is very good, but not at the same level as Iwata or Olympos provide. Pic 3 With that said, the mechanical fit of the parts that make up the brush is every bit as good if not better than those other brushes provide. Obviously, the Krome does not sell for anywhere close to the same price as those airbrushes demand, so you will have to take those factors into account when you decide how to spend your money.
The balance and weight of this airbrush is very good as is the trigger action. The trigger is one of the highlights of this brush and is extremely smooth and very responsive. It features a proprietary coating that is designed to significantly reduce friction between the trigger and the back lever thereby improving the feel of the airbrush. I will say that in my opinion, it does a wonderful job of doing just that, since the trigger pull on the Krome is every bit as good if not better than my Iwata HP series brushes. Tension can easily be adjusted via moving the spring screw to match whatever resistance you prefer. Another, well executed feature on the Krome is the graduated needle stop located on the rear of the cutaway handle. Pic 4 This item is great when you’ve got a lot of time invested in a model and you don’t want to chance pulling back too far on the trigger and ruining your work. It allows you to accurately preset your spray pattern for maximum width and repeat it continuously for as long as you need to. The needle stop positioning is firm and consistent so if you bump the rear of the brush, you shouldn’t have to reset your needle travel. The color cup is a generous size for a detail oriented airbrush and comes with a tightly fitting metal lid. The shape of the color cup is wide open and provides great access for cleaning. Additionally the cutaway section in the rear handle is geared towards quick cleaning or clearing of blockages during work sessions. This is a problem area for many brushes, as they often allow your hand to come in contact with your hand while moving the trigger. Badger has designed the Krome with a rubber O-ring on the rear handle to allow positioning the cutaway area in whatever orientation you choose. Pic 5 Another item that helps create a great feel for this brush is the finger rest attached to the air valve. This item originally appeared on the Badger Sotar and it makes the Krome very comfortable for long spray sessions. Personally, I believe it should be included on all Badger’s brushes if possible.
The Krome nozzles are small and easily lost but are rugged enough for consistent long term performance. They are also very well machined and smoothly finished. The brush features an air cap that has two needle protection prongs for the .21 tip which allow spraying very close to the surface being painted. The air cap for the .33 tip does not have those prongs, so exercise extreme care if you choose to spray close to any surface as the needle is very easy to damage if you touch the item being painted. Replacements of these items are readily available and relatively inexpensive when compared to some other airbrushes on the market. Should you damage these items the cost for both replacements together will run around $18-20.00. With normal use and care, I have never had to replace a nozzle or needle in this brush.
In Use Results
The Krome is definitely a fine detail airbrush. Its .21mm tip is regularly used by those who are pre or post shading a model, spraying free hand camouflage at low pressures or airbrushing highly thinned paints or inks for area washes, weathering or filters. While it can be used for applying paint to larger areas, it will require more coats of paint to achieve good coverage and it will require substantial patience when compared to the general purpose brushes with larger tips. This is not a design flaw, just a consequence of the design choices needed to produce very fine atomization and small clean lines. As with all detail brushes, a little paint goes a long way. The performance with the .33mm tip was more typical of general modeling brushes, with slightly poorer atomization than the smaller tip and faster paint consumption. It still did not consume paint very quickly.
The first paint used to evaluate the brush’s performance was Vallejo Model Air. Pic 6 This paint is packaged in dropper type bottles and is advertised by the company as being “airbrush ready”. The paint was shaken well, put into the color cup and sprayed unthinned at onto a piece of clean Evergreen sheet styrene. The Vallejo paint sprayed with a grainy pattern when covering larger areas. Pic 7 This indicated poor atomization so I experimented with variations in pressure to ensure best performance. Best atomization of the unthinned paint through the Krome using the .21mm tip was achieved at 15-18 PSI (1-1.25 bar). At this setting, the airbrush consistently sprayed patterns of 1/8” (2.7 mm) with minimal overspray but it still displayed a grainy spray pattern. Overspray increased dramatically when lines above this size were attempted. The smallest lines achieved without thinning were .010” (.26 mm) and were achieved at the same pressure. Tip dry was a huge issue when spraying Vallejo Model Air unthinned. Maintaining consistent performance was a chore as spraying more than 2-3 seconds would cause degradation of spray pattern. Pressure changes did not improve this situation.
The airbrush was cleaned and a new Vallejo Model Air mixture thinned 3 parts paint to 1 part Vallejo 71.161 Airbrush Thinner. Pic 8 With this mixture, the Krome sprayed best at 9-12 psi (.6-.8 bar). The wide spray pattern was 5/32” (3.85 mm), but the amount of overspray and graininess was much less. Pic 9 The fine line work with this mixture was improved, achieving unbroken lines of .006” (.15 mm) with very minor tip dry and no overspray. Clearly and as expected, the .21mm tip performed better with thinner paint. I did try thinning the Vallejo and dropping the pressure more, but the paint lost its consistent spray pattern and controllability.
The next paint I used to evaluate the Krome’s performance was Tamiya’s standard acrylic line. Pic 10 Tamiya’s paint is not “airbrush ready”, so I thinned the initial batch 1 part paint to 1 part thinner. This 50/50 ratio is a common mix recommended by Tamiya when using their X-20A thinner, so I used it as a starting point with the Tamiya’s yellow top lacquer thinner as well. PIC 11 I use both of these thinners when spraying Tamiya paints since there are times when I want more “bite” than the X-20A will produce, such as when spraying base coats or on bare plastic. I use X-20A when I need to lay acrylics over enamels without damaging the base coat. I use the same thinning ratios regardless of which Tamiya thinner is used. The 50/50 mix sprayed well with good atomization at 15-18 PSI (1-1.2 bar) but displayed a good bit of tip dry. PIC 12 The airbrush produced a consistent 1/8” (3.2mm) spray pattern which was easy to maintain and had a minor overspray and tip dry. Fine line work yielded a .011” (.28mm) line that was repeatable, with good color saturation but when pressure was pushed higher or lower, the results became inconsistent.
Increasing the ratio of thinner to paint to 3 parts thinner to 1 part paint yielded much better performance. This mixture is thinned to the consistency of skim milk which most airbrush users are familiar with. I was able to produce a repeatable 5/32” (3.3mm) wide spray pattern, but the atomization was substantially better than with the 50/50 mix and I would classify it as very good. Pic 13 Fading and shading were seamless and fine lines of .006” (.16mm) could be maintained and repeated at pressures between 9-11 PSI (.6-.8 bar) without tip dry. Additional thinning of the paint is possible on primed surfaces but thinning the paint more resulted in uncontrollable lines since I was painting on bare plastic.
Pic 14 When the .33 tip was installed Vallejo Model Air was placed in the airbrush unthinned. The Vallejo paint sprayed with unimpressive atomization, achieving best performance at 18-21 PSI (1.25-1.4 bar) with the larger tip. Pic 15 At this setting, the airbrush consistently sprayed patterns of 7/32” (5 mm) with minimal overspray. The smallest lines achieved without thinning were .025” (.64 mm) and were achieved at the same pressure. Tip dry was an issue when spraying Vallejo Model Air unthinned. Maintaining consistent performance was a chore as spraying more than 5-10 seconds would cause degradation of spray pattern. Pressure changes did not improve this situation.
The airbrush was cleaned and a new Vallejo Model Air mixture thinned 3 parts paint to 1 part Vallejo 71.161 Airbrush Thinner. With this mixture, the Krome sprayed best at 9-12 psi (.6-.8 bar). The wide spray pattern was 7/32” (5 mm), but the amount of overspray and graininess was much less. Pic 16 The fine line work with this mixture was improved, achieving unbroken lines of .015” (.38 mm) with very minor tip dry and no overspray. Clearly and as expected, the .33mm tip had better performance with the thicker paint than the .21mm tip had, but still required thinning to perform its best. I did try thinning the Vallejo and dropping the pressure more, but the paint lost all controllability.
Next, I used Tamiya’s standard acrylic line to evaluate the Krome’s performance with the .33 tip. The 50/50 ratio recommended by Tamiya was the starting point with the Tamiya’s yellow top lacquer thinner. The 50/50 mix sprayed well with good atomization at 18-21 PSI (1.2-1.4 bar) but displayed a good bit of tip dry. PIC 17 The airbrush produced a consistent 7/32” (5mm) spray pattern which was easy to maintain and had a minor overspray and tip dry. Fine line work yielded a .026” (.67mm) line that was repeatable, with good color saturation but when pressure was pushed higher or lower, the results became broken and splotchy.
Increasing the ratio of thinner to paint to 3 parts thinner to 1 part paint yielded much better performance. I was able to produce a repeatable 7/32” (5mm) wide spray pattern, but the atomization was substantially better than with the 50/50 mix and I would classify it as very good though not quite at the level achieved with the .21 tip. Pic 18 Fading and shading were good and fine lines of .014” (.36mm) could be maintained and repeated at pressures between 9-12 PSI (.6-.8 bar) without tip dry.
For the cleaning step, I emptied the reservoir, filled the cup with appropriate thinner and used an old paint brush to swab the cup and get into the recessed area behind the nozzle inside the color cup. I sprayed until the output of the brush was clear and then followed up with a lint free wipe to finish the color cup. The needle was then removed and a solvent soaked interdental brush was run into the needle bearing to remove any debris that might be pulled back into it when the needle was removed. I will mention here that the wide mouth, chrome finish of the color cup makes this an easy to clean brush.
The Badger Renegade Krome is a very fine airbrush. It offers very good atomization with properly thinned media, world class detail potential with model paints, great ergonomics and modeler centric features. Additionally, the interchangeable tips and needles bring additional value not provided by most of the brush’s competitors. If you are in the market for a fine detail or general purpose airbrush, I would highly recommend you include this airbrush in your consideration. The next review on deck after I move to a new location is a brush of a different sort; the Grex Tritium TG3.