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Legion
26th October 2014, 03:11 PM
I love welding and fabricating. I hate painting. I spent all day yesterday brush painting SHS. With my new compressor I'm thinking about finally venturing into spray painting. Even if I spend a few hundred dollars it'll be worth the saved effort to me. My question is - all the online articles and videos I watch are geared up to spray panels. Is spray painting still worthwhile for small tube (and even mesh, got a mesh job coming up) given that there will be lots of overspray to prep for and control? I.e. can you just turn down the fan shape and paint delivery (and maybe pressure) and fine up the spray pattern and get good results on e.g. 50mm SHS? 25mm SHS? Mesh?

On mesh I know there'll be heaps of overspray but brushing mesh sucks and so do the results. Even on SHS if I could do it in a fraction of the time for much better results that would be great.

rob streeper
26th October 2014, 03:16 PM
Spraying is the way to go. Hand painting mesh will drive you crazy, I've done several projects lately with mesh/ expanded metal and am really glad I resisted my impulse to stinginess. A good spraygun, even if used occasionally, will save you a great deal of time. Get a good organics mask and a good paint gun such as a SATA or IWATA and you won't miss the money wasted on overspray.

Legion
26th October 2014, 03:26 PM
All my work is done in the backyard/driveway. So with things like mesh, do you lay it down on a big piece of cardboard or layers of butcher's paper and that's it? Pick a still day so I don't coat the whole garden and back of the house? I certainly won't have a spray booth and doubt I'll ever have enough jobs to justify fabricating my own screens, especially since each thing I make tends to be a one-off.

I've been looking at HVLP guns but there's lots of information out there as to how current trends chop and change as to which sort of guns to buy, which are the best. I did find a SATA NR200 secondhand in the classifieds at about 1/4 new price but consensus seems to be to avoid used or they might not be in such good shape and require a rebuild.

rob streeper
26th October 2014, 03:32 PM
All my work is done in the backyard/driveway. So with things like mesh, do you lay it down on a big piece of cardboard or layers of butcher's paper and that's it? Pick a still day so I don't coat the whole garden and back of the house? I certainly won't have a spray booth and doubt I'll ever have enough jobs to justify fabricating my own screens, especially since each thing I make tends to be a one-off.

I've been looking at HVLP guns but there's lots of information out there as to how current trends chop and change as to which sort of guns to buy, which are the best. I did find a SATA NR200 secondhand in the classifieds at about 1/4 new price but consensus seems to be to avoid used or they might not be in such good shape and require a rebuild.

I have exactly that gun and love it. It allows for the adjustment of the spray pattern from narrow to broad with a thumb wheel immediately at the top of the grip - easy to do on the fly. I suggest going to check it over. Damage will be obvious - dinged spray tip/needle, loose or stuck needle, damaged reservoir seat are about it and are all easy to spot. Scratches to the outside of the gun in other places are merely cosmetic.

As to spraying technique, I do what's easy. If the finished construction will lay flat I spread out a cheap plastic sheet or tarp and spray. If the object is taller I put a drop cloth under it to avoid spraying the wife's landscape accents. Longer distance spray drift is minimal.

The important thing to remember about the HVLP's is keep the pressure low and your paint thin - about like milk for a gravity feed gun. I use lacquer thinner or mineral spirit for oil based paints and ~25% v/v Floe-trol for enamels.

P.S. Seal sets for these guns are two or three little Teflon bits - easy to change and relatively cheap.

Master Splinter
26th October 2014, 03:44 PM
You could do a lot worse than to start with this:
http://www.vektools.com.au/workquip-air-tools/workquip-gravity-spray-gun-with-stand-tip-setups-p-3556.html

Gravity fed, three tips (1.4, 1.8 and 2.5mm) for different materials (enamel, acrylic and spray putty).

If you're looking for a car-like high gloss off the gun in a production setting with no need for compounding, sure, one of the big brand name guns; if it's just in the shed with whatever insects or dust is around it would be a bit like buying a lee valley plane to tidy up your pine wall studs before you put plasterboard over them.

I recommend both the Custom Spray Mods channel as well as the various spray painting videos by Kevin Tetz on YouTube.

rob streeper
26th October 2014, 03:50 PM
I was given a cheap gun. It's a copy of the expensive German one. Piece of junk, dribbles down my hand and spits all over the workpiece. Sometimes cheaper is good, many times not.

Legion
26th October 2014, 03:56 PM
I'll look at a few before deciding. One I noticed was from American ebay:

http://www.ebay.com.au/itm/331353632456

Quality brand, cheapest line from them. They also do a two-gun set without the touch up gun.

The SATA is about a three hour round trip so I'll think about it.

rob streeper
26th October 2014, 04:00 PM
I'll look at a few before deciding. One I noticed was from American ebay:

http://www.ebay.com.au/itm/331353632456

Quality brand, cheapest line from them. They also do a two-gun set without the touch up gun.

The SATA is about a three hour round trip so I'll think about it.

If I was you, I'd be on that SATA like a duck on a Junebug. You might ask the seller to send you some pictures.

rob streeper
26th October 2014, 04:02 PM
I'll look at a few before deciding. One I noticed was from American ebay:

http://www.ebay.com.au/itm/331353632456

Quality brand, cheapest line from them. They also do a two-gun set without the touch up gun.

The SATA is about a three hour round trip so I'll think about it.

I used a DeVilbiss suction gun when I was a kid, about 40 years ago, and it was state-o-the-art for the time. SATA's are great but I've heard from some that Iwata's are better. Buy the best and only cry once.

BobL
26th October 2014, 04:05 PM
A vented booth is well worth the effort to setup as it can be used for a lot more than spray painting.

I do all my welding/cutting/grinding/sanding/painting in/near the both and it really helps keep the level of grey dust down in the shed.

My booth is small but I spray as much as I can hanging on hooks in the booth and if there are too many items I move the once painted items to other parts of the shed or even outside.
http://www.woodworkforums.com/attachment.php?attachmentid=211700&stc=1&d=1339244827
More details here http://www.woodworkforums.com/showthread.php?t=134670&p=1502826#post1502826

Some of the welding/cutting/grinding jobs don't fit in the booth but the fan helps clear the air very quickly and I can easily weld small galv jobs with any problems.

The fan is also useful for venting fumes from brush painting, chemicals or solvents it vents.

The only thing it can't keep up with is my forge but I have plan B just about completed to deal with that.

One thing that I have found really useful is a small (300 mm diameter turntable (runs on a lazy suzan bearing) on a short (400 mm high) pedestal, it works really well.

Legion
26th October 2014, 04:07 PM
In that case I've been doing a lot of crying lately.

But brush painting makes me cry too so spending on a spray gun is a win/win.

rob streeper
26th October 2014, 04:11 PM
In that case I've been doing a lot of crying lately.

But brush painting makes me cry too so spending on a spray gun is a win/win.

You won't regret getting a good spraygun. In some areas cost and quality are positively correlated. Buy a good one and don't loan it out.

Steamwhisperer
26th October 2014, 04:41 PM
When I spray mesh I stand to one side to in effect close up the gaps rather than standing directly in front.
I'm not even sure it makes a difference but it makes me feel better.

Phil
Ps I have only ever used a Star S660 (I think that's the number) and find it excellent.

Pete F
26th October 2014, 05:52 PM
Ok I will try posting AGAIN before I smash the POS ipad into a billion pieces! It's doing my head in :((

I'm normally a fan of buying good tools once and then looking after them. However this is one area where i don't think it's necessary unless you plan to do serious car restorations etc, and even then I've seen great results off reasonably cheap equipment. I did a workshop with this company 1 1/2 times (the second time I didn't know it was on and just happened to be there on the day so sat in again) http://www.vgautopaints.com.au they run weekend workshops on spray painting. My best mates had a crash shop too, so I used to spend a lot of time in there. VG Autopaints are agents for top brands and are more than happy to take people's money if you want to buy them, but for most work they recommend an inexpensive kit just over $100 bucks. I'll link to it later, lest this POS dump the whole post yet again. I have 3 guns similar to these, and they work just fine. It's quite amazing how they can sell them so cheap in fact, as when you look at them they're quite well made and intricate in areas. I'd just stay well clear of hardware style guns, I bought a small touch up gun from Bunnings and it's crap.

At the end of the day, don't overlook the humble rattle can. The paint in them is rubbish, is very thin so it atomises properly through the nozzle, so runs can be a real problem sometimes, but used with care there's no shame in them for this type if work. If I have a larger fabricated piece I'll set up with a gun, but for smaller pieces a can of spray paint is often sufficient.

ok here's the link to the gun http://www.vgautopaints.com.au/component/virtuemart/229/4/spray-guns/professional-gravity-spray-gun-1-4mm-and-2mm-tips-detail?Itemid=0

Bob38S
26th October 2014, 06:15 PM
Ok I will try posting AGAIN before I smash the POS ipad into a billion pieces! It's doing my head in :((

……..

ok here's the link to the gun http://www.vgautopaints.com.au/component/virtuemart/229/4/spray-guns/professional-gravity-spray-gun-1-4mm-and-2mm-tips-detail?Itemid=0

I don't have any problems or issues using my iPad for posting on the forum. It is my understanding that issues can arise if/when using the tappatalk type of application. The only issue I have had is when I neglect some of the "suggested words" and it doesn't write what I want. On my iPad I see the forum exactly as I see it on my iMac and it functions identically.

Just a suggestion.

KBs PensNmore
26th October 2014, 06:36 PM
I use an elcheapo Scorpion brand touch up gun for all my small work and find that it is excellent, the fan and volume easily adjustable. The important thing with them is to keep them clean, spray a cleaner through it, wash the outside, a bit of vaseline on the needle where it goes through the trigger (stops the seal from drying out) and the jobs done. For really small jobs, I prefer spray cans as it takes longer to clean the gun than to paint it. Like someone else said don't lend them out.
Kryn

Pete F
26th October 2014, 06:40 PM
No I don't use tappatalk. What I do however do is spend 6-9 months if* my life tapping in to this POS, and trust me, the novelty of it wears off real soon! My favourite is PM as it re-formats the screen twice after rendering. The delay is invariably just perfect timing so it will shift the link just as you press it, the result is it opens the wrong page. :doh: The only real solution is to open the page and sit there waiting for 10-20 seconds while it shuffles things around the screen. Not an issue once, but I read that forum a lot and that gets real tedious real fast, especially as I'm often doing so while trying to do something else concurrently.

I'm normally a big fan of Apple products, but I'm not the only one who uses it for work who are looking forward to the new models! I'm at the point where I'll probably start hauling a MacBook again soon, the ipad is just stretched too far.

Anyway, OT albeit a frustrating one.

* case in point, it often misses the o and will select the i, I proof read before posting, but often I won't notice this one and I need to edit the post.

morrisman
26th October 2014, 07:03 PM
The gravity guns are the way to go . These type of guns bring the amateur painter into the world of a decent spray job without the years of frustration and pain associated with suction guns . The use of suction guns effectively , requires a fair amount of skill and practice and patience . The gravity guns take a lot of the awkward paint viscosity and set up experience out of the equation - they are heaps easier to use .

All I have are the super crap auto low pressure gravity guns, they had a sale on at one time and I bought two of the basic guns , they work quite well .

I struggled for years with antique old worn out Arnold suction guns , these guns were very fussy to use , being prone to blockages Mike

Master Splinter
26th October 2014, 09:47 PM
I've been quite happy with my Workquip cheapie, and, yes, easier than the CIG/Arnold brand suction gun I had before.

For small work I have a $30 ($24 when on special) Supercheap single action air brush and it lets me do stone chip touchups on the car almost with pleasure.

Even the Supercheap budget enamel spray cans (currently on special at 5 for $10) work out ok for me - but I warm them in a bath of hot water if I'm using them on a cold day, and I drop the nozzles from empty cans into a jar of thinners to clean them so I always have a collection of clean nozzles on hand, if required.