gravity fed HVLP guns

[woodturner]

I was already to buy one of these guns when I talked to an old time painter and he said that he tried a gravity fed gun painting a tractor and found that he had a tendency to spill paint from the gun trying to get to the hard spots, and would never use it again. I have not read any problems like this on this site. Has anyone else had simular problems working on a tractor or has he just not had enough expreience with this type of a gun?

 

[Rod (NH)]

Having used a pressure-fed, remote cup arrangement for a long time, I find the full-sized gravity-fed guns a little hard to get used to. I am not used to and do not like the weight in my gun hand - a "top heavy" weight to boot. One of my spot guns is gravity-fed and I do not find that to be a problem simply because of the much smaller cup size. In any event, it's something you have to get used to I guess. One thing I would suggest is to find a gun with a solidly attached cap for the cup - e.g. screwed on or twist lock style if you can find one. Both my gravity-fed guns have friction type plastic caps. The cap for my spot gun is somewhat difficult to fully insert. I once thought it was installed correctly and it wasn't. The whole cap fell off during a painting session and dumped an almost full cup all over me and the ground. That happened on the last coat no less when I was spraying at an odd upward angle. What a pain. I've never had an issue with paint dripping out the small vent hole however. Unlike a remote cup arrangement, the gravity guns are not intended for painting upside down or even near upside down, although that presumably can be accomplished by using plastic baggies inside the cup if those are available from your gun manufacturer or can be cobbled together in some fashion. I've never tried that. Another thing I have noticed with HVLP is the apparent slowness of the gun - at least compared to a pressure feed setup. I can't remember way back when I used a suction feed gun relative to speed of HVLP.

 

[CNKS]

I have very little experience with suction feed, but when I did, I lost paint out the vent hole, likely due to lack of experience. I don't believe I have ever lost any out of a gravity feed. Like Rod, many experienced painters don't care much for HVLP. In my opinion, if you have never painted before HVLP is the way to go. The upside down thing doesn't bother me, because I paint the underside at an angle, and unless the correct police lay on their backs and look up, it is not noticeable. I am sure that if sheet metal was on the underside instead of cast, there certainly would be a difference. Cast is very forgiving due to it's rough texture, and you don't have to see yourself in it. I am NOT disagreeing with Rod, but it is all in what you are used to. When I started I wasn't used to anything, so HVLP works fine for me. Suction feed and HVLP have different techniques and the change from one to the other may be difficult to do, that's all. I have never used a pressure pot, there are times that it would be handy.

 

[glennster]

just about any spray gun can drip paint, it seems to only do it when you absolutely need it not to. what we do here at the shop, (we use hvlp gravity guns only, its the law in our county) apply masking tape to the rim of the cup to be sure the cup does not separate from the lid. also, use wide tape 2 inch and let half of it stick up above the cup to provide a barrier incase the vent does spit. this also works on the siphon feed guns too, as the vent holes on those can also release. even the sharpe drip proof cups have been known to spit some. the two big advantages of the hvlp guns are lower overspray and a lot less material usage.

 

[spiffy1]

The last time I painted a tractor, I'd never heard of HVLP! Anyway, a few years back I did buy a fairly nice Devilbiss gravity set-up. They offer a zip-lock type bag liner (probably works with most guns), and I had no trouble even shooting above myself inside the horse trailer I was doing.

That said, we had some things around here last summer need paint so I tried that gun and recalling easier clean-up used a liner: The bag came loose, confusing the heck out of me on the sputtering, then making a big mess when I opened the cup! Guess nothing is fool proof, if you're a big enough fool?

 

[kballein]

I'm certainly not a professional but have painted a number of cars and a few tractors over the years. I used a siphon feed gun until about 5 or 6 years ago when I got my first HVLP. I know most of the discussion has been more about technique, but when you consider overspray and wasted material HVLP is definitely the way to go. It is a little hard to get used to, seems to put a lot more paint out than a siphon gun. I haven't painted too much overhead, but don't recall any paint dripping problems. I am usually spraying in my garage and less overspray is important. Modern primers and paint materials are expensive and HVLP puts more on what your are painting and less into the air.

Just my experience.

Ken

 

[john_Bud]

If you try and tip the gun down at a sharp angle with a full cup, yeah that could be a problem. Knowing that in advance, you can then wait until the cup is nearly empty to spray in those areas.

The cost of the HLVP gun is also quickly made up by the much lower paint use. Somewhere around 50% less paint is needed as there is so much more on the target and less in the air.

Naturally, some people like to keep using what they are familiar with and will find reasons to not change. That's ok, but you should recognize it and take that factor into account.

jb