Grex XD airbrush - quick look

DaveG

Airbush Analyst
I got asked about one of these in another thread, but thought to put the info here in case someone else should be curious, it won't be buried where it does not belong :)

I purchased Grex XD to satisfy my curiosity as to what the build was like in it's comparative price range. I chose the XD which has the smallest color reservoir with the intention of using the brush for fine detail work.

grex-xd-airbrush1.jpg
My impression is that overall, the fit and finish of the brush is pretty good. It feels nice in the hand. The bottom line on this brush is that I found it's action to be a bit ambiguous to use, and paint flow initiation can be a guessing game. This airbrush is capable of producing some nice, fine detail. On par with many other .2 set up's that I have. The issue for me, is that it is a brush that makes me work harder to achieve those results. For me, the trigger feels stiff, and is tiring to use for long periods. Even after quite a bit of fiddling with the springs, and such, I have not been able to achieve a feel with the trigger that I feel comfortable with. I've adjusted the needle chucking spring, and the trigger actions still feels a bit gritty and stiff - when compared to many other brushes I have.

In addition to lack of feel with the trigger, I find it hard to predict when the paint flow will be initiated through the stroke of the trigger. Hitting the sweet spot between air and paint delivery to get the finest of details is a real chore on this brush, and it does not seem to be consistent each time.

Head, nozzle needle - all look pretty standard. I have not had any trouble with these bits as of yet.
grex-head-on1.jpg grex-nozzle1.jpg

One of the reasons that paint flow may be a bit off - if you compare the above picture with the one below, you can see the Grex head allows for more room around the nozzle, as well as the nozzle being off center as compared to the Iwata HP-B+ head pictured below.
iwata-hp-b-head-on1.jpg

A direct comparison between the Grex XD (bottom) and an Iwata Hp-B+ (top) Grex-and-Iwata.jpg shows how close they are. Brush bodies are almost identical, they have the exact same length, and contouring towards the head end of business. Handles vary, so the overall length is just a tad different... While the head pieces look almost identical, the Grex nozzle uses different threads, and is a different length than the Iwata...

As it is, it remains a brush that I do not use very often, as I have others that are easier to use for anything I may decide to reach for this one for. It has also satisfied my curiosity, and I have not felt a need to purchase another.

EDIT: Since initially writing this, I took another look at my brush. Didn't think it would be fair to leave the nozzle that far off center if I was willing to fix some less expensive brushes. Vladimir had asked about the brass colored ring behind the nozzle. So, when I removed the nozzle to investigate an answer to his question, I took the time to concentrate on centering it when I reinstalled the nozzle. I got it much better, and found that it improved the line quality enough to call it a difference. While I was at it, I worked more on the trigger as well. In the end, maybe I am being a bit too harsh on the brush, as it will produce fine details. The one issue that remains is that paint flow initiation is a bit ambiguous. In order to work more consistently it is necessary to work at a higher initial air pressure than many of the other brushes I am used to. Of course, working at higher pressure brings it's own set of problems when trying to do fine details... It is necessary to use a fast, high pressure blast of air to get the paint drawn off the needle to start - but then you can let off on some air, and work normally - so, it helps to initiate paint flow on a scrap of paper held near the work surface, and then carry on to the task at hand. It will maintain a flow relatively easily.
 
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Thank you for sharing!
The guns looking like twins! Do you will do a little test?

Gesendet von meinem SM-G388F mit Tapatalk
 
Thank you for sharing!
The guns looking like twins! Do you will do a little test?

Gesendet von meinem SM-G388F mit Tapatalk

Thank you, Micha - have used the Grex a bit, and can indeed add more information for anyone interested. What I can say (and guess I can add back into the original post) is that, the airbrush is capable of producing some nice, fine detail. On par with any other .2 set up that I have. The issue for me, is that it is a brush that makes me work harder to achieve those results. For me, the trigger feels stiff, and is tiring to use for long periods. Even after quite a bit of fiddling with the springs, and such, I have not been able to achieve a feel with the trigger that I feel comfortable with.

In addition to lack of feel with the trigger, I find it hard to predict when the paint flow will be initiated through the stroke of the trigger. Hitting the sweet spot between air and paint delivery to get the finest of details is a real chore on this brush, and it does not seem to be consistent each time.
 
Thanx for sharing Dave!
Well described. I expected more from the brand. Serious doubts of trying it here...

What is in there between the nozzle and the body, seal?
 
Thanks for the info.

Although those guns are for minimum paint, you still need quite a bit of paint if you hold the gun horizontal. Those cavities, that is also found on most C guns, are too big and you need quite a few drops of paint to cover the needle.. It's not an issue if you hold the gun pointed down.
 
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Thanx for sharing Dave!
Well described. I expected more from the brand. Serious doubts of trying it here...

What is in there between the nozzle and the body, seal?

It looks like a bronze bushing. I have seen them used as seals in high pressure fittings, but never in a situation such as this. I have removed the nozzle from this brush in the past, and do not seem to remember a separate washer falling off anywhere, so am not sure if it is pressed to the body or not - will take another look at it. It is also more visible in the photo than by eye...
 
Thanks for the info.

Although those guns are for minimum paint, you still need quite a bit of paint if you hold the gun vertical. Those cavities, that is also found on most C guns, are too big and you need quite a few drops of paint to cover the needle.. It's not an issue if you hold the gun pointed down.

I assume you mean when the brush is held horizontal ;). I have had "A" cup brushes from several makers, including Badger, and Iwata over the years. In general I work with only one or two drops of paint in the brush, and no more than maybe 4. Although, I work on a tilted table rather than vertical easel.

This particular brush is stubborn about initiating paint flow - but I suspect it is more due to the large spacing between air cap and nozzle tip rather than depth or shape of cup. In my experience the needle does not need to be covered for the brush to work as designed. As long as there is enough paint to create a meniscus along the needle, and the mouth of the channel the needle runs through - you are good to go. When I put paint in the brush, I usually put the drop right at the front of the cup. Surface tension, and capillary action will work to pull the paint into the brush, and the venturi at the nozzle will draw it forward to be atomized. I am sure if you held the brush either perfectly horizontal, or perhaps tilled upward a little, one would have a hard time maintaining paint flow once the paint in the channel between color cup and head was used up...
 
It looks like a bronze bushing.

Another surprise from the brand:) I wonder why they install it there.

And it looks like Iwata has better polished body before the plating, at least that's what I see from the photo.
 
Another surprise from the brand:) I wonder why they install it there.

And it looks like Iwata has better polished body before the plating, at least that's what I see from the photo.

I would not make much effort to compare the quality of the Grex to that of the Iwata. While I do not find the Grex to be horrible; most surfaces feel smooth, there are not many visible machine marks, and parts do not feel loose or sloppy - they are in no way in the same league as compared to Iwata. I will also mention that most often, the camera lens will pick up things that may not be so obvious to the naked eye and magnify the imperfections.
 
After reading you comment, I was curious (never stopped to think about it before) so I went and loaded the Grex XD up with one drop of paint (actually, closer to a drop and half - there were a few bubbles that came out first). Initiated paint flow in a normal position (like your second picture), and then held the brush vertical - head pointing straight up. I paused a few seconds to allow what little paint was left in the cup to flow towards the back of the reservoir, and then initiated air flow and needle draw - the brush continued to paint without issue, and would have till the paint trapped in the needle channel was depleted...

cup with 1.5 drops of Golden Shading Gray (sorry, should have chosen a color more visible) This is typically about how much paint I work with in this style brush. A note here, the paint has covered the needle where it enters the brush body not simply by liquid level, but by meniscus action, and surface tension. As long as there remains enough liquid to feed this area, paint will continue to be drawn towards the nozzle.
color-cup1.jpg

Bottom line painted with brush in a normal position if working on a slightly inclined drawing board. Top line painted holding the brush completely vertical after initiating paint flow in a normal position, stopping, and then starting again when brush was pointed straight up. Awkward position, so don't judge line quality -

position-test1.jpg
 
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Another surprise from the brand:) I wonder why they install it there.

I took another look at the nozzle set up on the Grex - It looks to me like they pressed a threaded brass sleeve into the body of the brush once it was already plated to accept the nozzle. I am just guessing that it is pressed in vs. threaded, but I am not going to attempt to remove it ;). (sorry I missed on the focus!)

head-insert1.jpg
 
Why did you choose the XD? Was is simply because the small paint reservoir?
The XGI which I believe is a newer design has a removable paint cup which let's you put a drop or two into the small valley.
What made you pick the XD over the XGI,XSI?
 
Why did you choose the XD? Was is simply because the small paint reservoir?
The XGI which I believe is a newer design has a removable paint cup which let's you put a drop or two into the small valley.
What made you pick the XD over the XGI,XSI?

There are several reasons that I chose the XD -

One of my very first airbrushes was a Badger 100G, almost 30 years ago. I quickly added both the 100LG and 100SG to my arsenal at that time. The Grex brushes look to me to be a more modern take on those same brushes - so there was some sentimental consideration. My original thought was to try one, then add the two other cup sizes. I chose the "A" cup size to start with, as I have quite a few "B" and "C" cup brushes already.

Second thing was price - the XD was about $75 cheaper than others mentioned...

Third thing is that the XG-X and XS-X brushes look to have a trigger that is a copy of the H&S Infinity. The H&S brushes cover the exchangeable cup size niche - so that factor is not necessarily an attraction. I have a couple of H&S brushes, and had no desire to purchase a copy at a fairly premium price.
 
hi guys im new, but i want to say i have the xg2, side feed genesis model and that airbruah is superb. it can pull a fine line and work at low pressures and higher pressures for great coverage, i also have an xn but i agree with you with getting the paint to flow, but grex"s new models are deffitinely an improvemeny by far, and i only got my for $128, the side feed brush, 3 cups, and grip and, and i dont think they really copied harder and steenback, the trigger is similar. but the grex is smooth and the grex does shoot paint faster, i find myself using the bruah more and more each day, and my history i owned iwatas and i sold them as fast as i got them, they werent for me, but out of 15 airbrushes, my line is mr supreme procon boy .18mm, grex xgi2, and holbein toricon, and they all do the same thing from the finest of lines to broad spraying but the grex shoots out paint faster like i said, a teue definition of a spray gun, but my favorite the holbein can handle the lowest of psi and produce same results as my .18
 
Yes there is very big difference In the original XG and older models and the new XGI (Genesis and tritium).
 
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