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Is it true that ...say... if you are spraying a big flat board of wood on the floor you should not hold the spray can parallel to the board (so the jet is spraying directly onto it) but try to keep the spray can vertical and spray in such a way that the spray angles downward onto the wooden board?

Or is it irrelevant how you hold the can while spraying? I thought that there might still be paint in my can but I ran out of gas because I wasnt spraying properly


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has anyone had experience with spraying more than short bursts at a time for small figurines?

I haven't found can orientation to be particularly important, so long as you don't go so far from vertical that that the feed tube inside the can is no longer reaching paint (why turning a can upside down and spraying lets you clear the tube and nozzle) and your spray is actually hitting the intended surface.

Most can instructions will tell you to do even sweeps across the surface, starting and ending slightly beyond the target. I find that, unless you're doing lots of very light/quick passes, this can easily lead to pools or runs, if your speed and stroke overlap are a bit off. I prefer to move quickly - almost erratically, by all appearances - simply watching the surface to see where I need to increase coverage. Works as fast as any other method, but is harder to muck up, as it's so intuitive - you're focusing on the surface and watching the results build in real time, not trying to follow a prescribed motion and "check in" between passes. Moving the can quickly means you need to hit an area way too many times to get really excessive buildup.

I was trying to get one half of a bisectioned 6' x 4' board (i.e. a 3' x 4' board) covered in dark grey for an urban themed board, so used The Fang spray, but couldnt get more than two thirds of said board covered before I ran out.

If you're trying to cover a large area I recommend buying large pots of paint. I've played the "try to spray a board" game and you go through several cans to get it done. Or else just get cheaper cans of paint if you can find the right colour.

For spraying large flat areas, like a board, You're going to want a can with a fan spray, which counters the usual dot spray that we normally like for spraying models.

The professional solution is an HVLP spray gun.. but .. well.. theyre quite expensive and for a one off job a bit too much investment.
Many automotive paints have a fan spray pattern rather than a dot, I suggest looking for some like that.
In my local area the car panel replacement supplier will fill a spraycan with any colour you like that has a fan nozzle, while halfords only stock dot nozzles.

I actually think there's still some paint left in my can but I just ran out of gas...do you think it's economically feasible to refill the GW spray can or is buying another one the better idea?

Assuming the propellant inside the can is just compressed air, then *yes* the can could be re-pressureised by someone with an aircompressor and the appropriate valve for the airline to attach to the can.

Graffiti artists actually mix cans for new colours, or to move paint into their favourite can with optimal spray characteristics, it might be possible to move just air from a can of airbrush propellant in this manner, basically they put a thin pipe from one nozzle into the next and press both nozzles down- pressure will equalize across them, so moving from the higher pressure can into the lower.

Most spray cans need to be held as close to vertical as possible. Otherwise, you're spraying more propellant than product and you end up with what you have: a can with paint but no way to get it out :( Sprays are great for getting a consistent coat on irregular-shaped or small objects, but they are not cost-effective ways to to cover large flat surfaces. If you have to spray a large board, lean the board against a wall as upright as possible and protect the wall from overspray.

BTW, most brands of spray paint are meant to be disposable, and I strongly suggest that you do not attempt to refill it. The propellant is not compressed air, and by attempting to refill it, you will almost certainly rupture the can and possibly injure yourself.

When I spray models I use quick bursts with a flick of the wrist motion, left to right, at a downward angle (about 35 degrees), twice.

Its useful to stick models to a makeshift handle, empty paint pot, bottle cap or I even use a small length of wood with a dozen or so models stuck on with blu tack. Makes it so much easier.

 Sir Arun wrote:
do you think it's economically feasible to refill the GW spray can or is buying another one the better idea?

If you're dead set on your board being covered in the exact color of The Fang spray, just buy another can and finish it off. If not, I'd just cut my losses at one can and coat the entire board with a more reasonably priced paint.

The most economical method for covering large boards is to use latex/emulsion house paint. Custom color mixes (bring in a swatch and most home improvement/paint stores can scan and match it) are quite reasonably priced (for the volume you get, at least), stock colors are rather inexpensive, and mis-tints, if the store sells them off and you find a color you like, are dirt cheap. HVLP rigs are well beyond the realm of casual hobby spending, but you can get electric paint/stain sprayers for DIY use that might be worthwhile to a frequent terrain builder. Otherwise, just grab a cheap, wide brush while you're at the store. Even a large board gets covered pretty quickly using 3-4" brush.

Spray paints from more common brands come in a not too distant second to house paint, in terms of economy. You won't likely get that much more coverage per can from Krylon, Rustoleum, etc. but you'll pay a fraction of the price per can, so it's less of a blow to your wallet than a GW can getting used up. "House brands" from local stores (like Walmart's ColorPlace brand, stateside - Halford's has a similar line in the UK) are also a viable option. I use ColorPlace cans more than any other aerosol and I've used both Krylon and Rustoleum, before. You get less paint per can, but the cost is so low that it still has the edge in terms of cost per volume of paint.

Honestly, most of the information provided is quite solid. For minis, the downward angle of 35 degrees is great for minis. Occasionally I lay em on the backs/stomachs to hit the underside of the chest and armpits/backpacks. For boards I highly, HIGHLY suggest going with the large can of paint method. Spray cans will eat through your wallet, as an average board will take at least 6-8 to get a good base coating.

If you're dead set on spray, I would get cheap Krylon or whatever as close of a color as possible, otherwise this board will become a giant moneysink.

 the_Armyman wrote:
Most spray cans need to be held as close to vertical as possible. Otherwise, you're spraying more propellant than product and you end up with what you have: a can with paint but no way to get it out :( Sprays are great for getting a consistent coat on irregular-shaped or small objects, but they are not cost-effective ways to to cover large flat surfaces. If you have to spray a large board, lean the board against a wall as upright as possible and protect the wall from overspray.

BTW, most brands of spray paint are meant to be disposable, and I strongly suggest that you do not attempt to refill it. The propellant is not compressed air, and by attempting to refill it, you will almost certainly rupture the can and possibly injure yourself.

Provided the pickup is under paint - you will be spraying paint.

The pickup tube is a long flexible tube that gets pushed into the corner of the can. One can you will be able to hold horizontal and spray out most the paint - the next can the pickup will be on the other side and you will run out of propellant almost immediately. Most the time the pickup will be in a side somewhere between all the way up and all the way down though... Because of this, as mentioned above - vertical is the best way to get the most out of the can. If you are not vertical, there is a good chance you will be leaving paint in the can.

Regarding rupturing the can - very unlikely...unless you tried REALLY hard, and most home users wouldn't have the ability to burst a can short of a firepit. At room temperature, a new can of paint is charged to around 100 PSI (dependent on brand and size of can). Regular shipping conditions can expose cans to almost twice room temperature - which would increase the pressure to almost 200 PSI. Engineering standards dictate a safety factor of 25-50% minimum for pressure vessels - which means it shouldn't burst until somewhere around 250 PSI. If you have access to pressurized gases like compressed nitrogen or carbon dioxide - or access to an industrial air compressor...you could probably blow one up. However, if you have access to those...you will probably know better. Regular portable compressors normally have a cut off of under 150 PSI - so try as hard as you want to, it won't pop off.

Granted, you could fowl the valve and cause the paint to shoot out uncontrollably without much difficulty - seen that happen a couple of times.

For this particular task - I do have an HVLP...and it is butter for covering everything evenly. However, my old, worn and tired Badger 350 does this work more often than not. The much derided external mix, single action airbrushes are ideal. You can get a big 3 ounce bottle, put on the heavy tip, crank your pressure up to 50 PSI and spray unthinned house paint. You can get your spray pattern to be 2-3" wide...so covering large areas goes pretty quick.

To the OP, spraying a full board with a rattle can is pretty much a waste of expensive paint. Use the cheap stuff, or better yet, use standard house paint.

Spray paints don't tend to cover wood very well, so that may also be part of your problem.

Also, from what I've seen, to get a good paint mix, some people use plaster of paris, acryclic paint, and sandbox sand to get a gritty texture.

 jreilly89 wrote:
Also, from what I've seen, to get a good paint mix, some people use plaster of paris, acryclic paint, and sandbox sand to get a gritty texture.

I used this, plus pumice texture additive for my home board. Then I basecoated it in brown rustoleum camo paint. Worked well, it's not going to win any awards, but it's a nice table to play casual home games with.

 Sean_OBrien wrote:

Regarding rupturing the can - very unlikely...unless you tried REALLY hard, and most home users wouldn't have the ability to burst a can short of a firepit. At room temperature, a new can of paint is charged to around 100 PSI (dependent on brand and size of can). Regular shipping conditions can expose cans to almost twice room temperature - which would increase the pressure to almost 200 PSI. Engineering standards dictate a safety factor of 25-50% minimum for pressure vessels - which means it shouldn't burst until somewhere around 250 PSI. If you have access to pressurized gases like compressed nitrogen or carbon dioxide - or access to an industrial air compressor...you could probably blow one up. However, if you have access to those...you will probably know better. Regular portable compressors normally have a cut off of under 150 PSI - so try as hard as you want to, it won't pop off.

This is all true, but I wouldn't tell anyone who isn't familiar with pressurized gases to refill what are essentially disposable containers. For work, I used to have to refill cylinders from a mother tank at home. The little cylinders were about as thin as a can of Red Bull, but a little longer. However, these tiny little bottles were filled at nearly 2000 psi. They would get hot to the touch when refilling. If I didn't know better, I could probably jury-rig a connector to fill a can of spray paint if someone on the Internet told me to...

 Sean_OBrien wrote:

Regarding rupturing the can - very unlikely...unless you tried REALLY hard, and most home users wouldn't have the ability to burst a can short of a firepit. At room temperature, a new can of paint is charged to around 100 PSI (dependent on brand and size of can). Regular shipping conditions can expose cans to almost twice room temperature - which would increase the pressure to almost 200 PSI. Engineering standards dictate a safety factor of 25-50% minimum for pressure vessels - which means it shouldn't burst until somewhere around 250 PSI. If you have access to pressurized gases like compressed nitrogen or carbon dioxide - or access to an industrial air compressor...you could probably blow one up. However, if you have access to those...you will probably know better. Regular portable compressors normally have a cut off of under 150 PSI - so try as hard as you want to, it won't pop off.

Granted, you could fowl the valve and cause the paint to shoot out uncontrollably without much difficulty - seen that happen a couple of times.

Agreed, but you also have to consider imperfections in manufacturing. They may be rated up to 250 PSI, but with imperfections that could be closer to 175 or 200. Yeah, you're not likely to pop it, but at $3 - $6 a can, why bother refilling it? Toss it in the recycling bin and buy a new one. Also, in what places are shipping conditions up to two times room temperature? 100 to 110 degrees Fahrenheit, but 130 to 140 seems a bit much.

 jreilly89 wrote:

 Sean_OBrien wrote:

Regarding rupturing the can - very unlikely...unless you tried REALLY hard, and most home users wouldn't have the ability to burst a can short of a firepit. At room temperature, a new can of paint is charged to around 100 PSI (dependent on brand and size of can). Regular shipping conditions can expose cans to almost twice room temperature - which would increase the pressure to almost 200 PSI. Engineering standards dictate a safety factor of 25-50% minimum for pressure vessels - which means it shouldn't burst until somewhere around 250 PSI. If you have access to pressurized gases like compressed nitrogen or carbon dioxide - or access to an industrial air compressor...you could probably blow one up. However, if you have access to those...you will probably know better. Regular portable compressors normally have a cut off of under 150 PSI - so try as hard as you want to, it won't pop off.

Granted, you could fowl the valve and cause the paint to shoot out uncontrollably without much difficulty - seen that happen a couple of times.

Agreed, but you also have to consider imperfections in manufacturing. They may be rated up to 250 PSI, but with imperfections that could be closer to 175 or 200. Yeah, you're not likely to pop it, but at $3 - $6 a can, why bother refilling it? Toss it in the recycling bin and buy a new one. Also, in what places are shipping conditions up to two times room temperature? 100 to 110 degrees Fahrenheit, but 130 to 140 seems a bit much.

Aerosol cans need to be able to withstand either 230PSI or 270PSI depending on what rating they are. That means imperfections and all, it's to ensure cans don't explode during transportation. I imagine the can designers go well in excess of that so they don't get sued if a can explodes in hot truck.

Plastic soft drink bottles can withstand about 100PSI

EDIT: Also, yeah, a truck or container in the sun can reach 130-140 degrees on a hot day. I wouldn't be surprised if it goes higher than that in some areas, and you have to design your cans for the worst possible transport situation unless you intend to sell one type of can in exclusively in cooler climates.

AllSeeingSkink wrote:

 jreilly89 wrote:

 Sean_OBrien wrote:

Regarding rupturing the can - very unlikely...unless you tried REALLY hard, and most home users wouldn't have the ability to burst a can short of a firepit. At room temperature, a new can of paint is charged to around 100 PSI (dependent on brand and size of can). Regular shipping conditions can expose cans to almost twice room temperature - which would increase the pressure to almost 200 PSI. Engineering standards dictate a safety factor of 25-50% minimum for pressure vessels - which means it shouldn't burst until somewhere around 250 PSI. If you have access to pressurized gases like compressed nitrogen or carbon dioxide - or access to an industrial air compressor...you could probably blow one up. However, if you have access to those...you will probably know better. Regular portable compressors normally have a cut off of under 150 PSI - so try as hard as you want to, it won't pop off.

Granted, you could fowl the valve and cause the paint to shoot out uncontrollably without much difficulty - seen that happen a couple of times.

Agreed, but you also have to consider imperfections in manufacturing. They may be rated up to 250 PSI, but with imperfections that could be closer to 175 or 200. Yeah, you're not likely to pop it, but at $3 - $6 a can, why bother refilling it? Toss it in the recycling bin and buy a new one. Also, in what places are shipping conditions up to two times room temperature? 100 to 110 degrees Fahrenheit, but 130 to 140 seems a bit much.

Aerosol cans need to be able to withstand either 230PSI or 270PSI depending on what rating they are. That means imperfections and all, it's to ensure cans don't explode during transportation. I imagine the can designers go well in excess of that so they don't get sued if a can explodes in hot truck.

Plastic soft drink bottles can withstand about 100PSI

EDIT: Also, yeah, a truck or container in the sun can reach 130-140 degrees on a hot day. I wouldn't be surprised if it goes higher than that in some areas, and you have to design your cans for the worst possible transport situation unless you intend to sell one type of can in exclusively in cooler climates.

Right, but I wouldn't trust hooking it up to an air compressor. Maybe a bike/basketball pump, but not an air compressor. And trust me, some people care about safety/lawsuits, but aerosol can manufacturers I wouldn't necessarily be so sure about.

Given my air compressor has a regulator on it which lets me set the pressure between the tank and the outlet and a pressure switch on the tank itself that cuts the compressor at 115PSI (actually I think it's less than that I don't remember off the top of my head)... I would have no problem hooking it up to a spray can.

(I'm not sure if it'd actually make the can usable again, I'm just saying I wouldn't be stressed about it blowing up and killing me )

AllSeeingSkink wrote:
Given my air compressor has a regulator on it which lets me set the pressure between the tank and the outlet and a pressure switch on the tank itself that cuts the compressor at 115PSI (actually I think it's less than that I don't remember off the top of my head)... I would have no problem hooking it up to a spray can.

(I'm not sure if it'd actually make the can usable again, I'm just saying I wouldn't be stressed about it blowing up and killing me )

Please don't try this, you're playing with fire. I've refilled fire extinguishers with paint and compressed air. But rattle cans don't use compressed air they use aerosol.

Edit; when i say aerosol I mean a propellant

I'm *holds fingers* this close to figuring out where Citadel gets there rattlers made. The propellant in it, is extremely familiar to a graffiti grade paint I used to use I just can't put my finger on it.... Anyways if I can figure it out it means getting citadel grade paint at half the cost.

shauni55 wrote:
Please don't try this, you're playing with fire. I've refilled fire extinguishers with paint and compressed air. But rattle cans don't use compressed air they use aerosol.

I will admit I've never seen someone do it with spray paint so if there's something specific that makes it bad to do with spray paints let me know... but I've seen people do this with spray cans of WD40 and degreaser and other random spray cans you use in your garage. I'm also not an aerosol expert so if any of my assumptions are wrong leading to wrong science feel free to correct me, lol.

The aerosol is just a gas that turns to liquid at the pressure you have inside the can, but at atmospheric pressure it's a gas. This means if you want to maintain 100PSI you can do it for considerably longer with an aerosol vs atmospheric air that stays a gas throughout the whole process, as you can fit a lot more liquid aerosol in to a can at 100PSI than you can fit gaseous air at 100PSI.

Aerosol is actually much more dangerous than air to have at pressure. If you just have air and it stays a gas, when you heat the can up, the pressure rises, but since the number of gas molecules remains the same and the volume remains the same, you can estimate the pressure rise by the ideal gas law. Going from 75F to 150F, the pressure only increases about 14%.

An aerosol, though, as you heat it up the boiling pressure also rises, so as you heat the can, you're actually increasing the number of gas molecules in the can as some of the liquid aerosol boils to maintain equilibrium. A spray can of aerosol going from 75F to 150F can increase in pressure by 125% (more than double the pressure).

That's why they tell you not to leave aerosol cans in areas that get very hot. But if they didn't use aerosol, you'd only be able to spray for a few seconds before the pressure dropped too low to spray.

So if you refill a can with air, you'll be able to spray with it again***, but you won't be able to spray as long as if you'd refilled it with aerosol.


***As I said, I have never attempted this with an actual spray PAINT, though I've seen people do it with spray cans of other types... hence why I said I'm not sure if it'd actually make the can usable again. But it's not uncommon in workshops just to squeeze a bit of compressed air in to a can to get out the last bit of WD40 after the propellent has run out.


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shauni55 wrote:
I'm *holds fingers* this close to figuring out where Citadel gets there rattlers made. The propellant in it, is extremely familiar to a graffiti grade paint I used to use I just can't put my finger on it.... Anyways if I can figure it out it means getting citadel grade paint at half the cost.

I just had a look at a couple of my Citadel cans. They say LPG on the side of them... maybe they're filled with liquid petroleum gas then?

@Allseeing

Thanks for the LPG tip Ill look into it. I've narrowed down to:

MTN (my first guess)
Montana Gold
Alien
Maybe a couple others

shauni55 wrote:
@Allseeing

Thanks for the LPG tip Ill look into it. I've narrowed down to:

MTN (my first guess)
Montana Gold
Alien
Maybe a couple others

We're drifting OT here, but I'd be interested to know the manufacturer, as well. Although the colors are probably proprietary mixes that aren't sold to anyone except GW.

Has anyone tried Montana Gold on their mini's?
Theres a huge range of colours for that. Liquitex also offering their own range of sprays which looks interesting.

Not specifically on miniatures, but on models.

Very smooth paint, but it is a lacquer. If you spray it on plastic without a primer coat...it can be problematic. If you are concerned about VOCs - move along, they have them all (Propane, Xylene, Acetone, Butane, Ethyl Acetate, Naptha, Benzene...).

Provided that that doesn't scare you off though - a primer coat of your choosing and then you can apply the Montana Gold. They cover pretty well, but most are a bit on the glossy side.


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 jreilly89 wrote:
Right, but I wouldn't trust hooking it up to an air compressor. Maybe a bike/basketball pump, but not an air compressor. And trust me, some people care about safety/lawsuits, but aerosol can manufacturers I wouldn't necessarily be so sure about.

Any company is concerned of lawsuits - they are also concerned about fines and government goons coming in and shutting them down. In order to ship the cans outside of their factory - they have to comply with certain regulations. In order to insure their assets - they have to maintain other aspects of their business. It is actually pretty easy to design and build a pressure vessel able to withstand a few hundred pounds of pressure...dirt cheap too. No reason to cut those corners for the little gain they might get out of it.


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 jreilly89 wrote:
Agreed, but you also have to consider imperfections in manufacturing. They may be rated up to 250 PSI, but with imperfections that could be closer to 175 or 200. Yeah, you're not likely to pop it, but at $3 - $6 a can, why bother refilling it? Toss it in the recycling bin and buy a new one. Also, in what places are shipping conditions up to two times room temperature? 100 to 110 degrees Fahrenheit, but 130 to 140 seems a bit much.

My car routinely hits 150 F during the summer. NHTSA tests have shown temperatures of 192 inside cars from normal weather conditions (normal for places like South Florida and the desert Southwest of the US). For the cargo truck full of rattle cans that is hauling down I-10 across the desert...they get pretty hot. Never put a thermometer to it, but when I lived in Texas...occasionally I would get a truck delivery via LTL. When they would pop that back door open, it felt a lot like when I would open the oven to take out the Thanksgiving turkey. This study (a truck driving from Dallas to Phoenix) showed temperatures over 120:

http://www.ista.org/forms/ISTA_Temperature_Report-2002.pdf

Regarding the defects...that is taken into account with the safety factor. The can itself is designed to handle the 250+ PSI (will depend on the engineer who signed off, and other factors...but 250 PSI would be the minimum). You assume there will be defects in manufacturing - so while a 1/32" side wall might be strong enough...you specify 3/64". That extra thickness allows an inclusion or other defect to happen and not result in a catastrophic failure.


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 the_Armyman wrote:
This is all true, but I wouldn't tell anyone who isn't familiar with pressurized gases to refill what are essentially disposable containers. For work, I used to have to refill cylinders from a mother tank at home. The little cylinders were about as thin as a can of Red Bull, but a little longer. However, these tiny little bottles were filled at nearly 2000 psi. They would get hot to the touch when refilling. If I didn't know better, I could probably jury-rig a connector to fill a can of spray paint if someone on the Internet told me to...

Like I said - if you have access to the means to rupture a can...you generally know better than to rupture the can. Generally speaking, if you have something capable of producing 200+ PSI you have many other ways of nearly killing yourself as well...your residential equipment just isn't going to cut it...

I guess some yutz could hook it up to the high side off from a CO2 tank for their kegerator...but, we need something to write up for the Darwin awards each year.

HairySticks wrote:
Has anyone tried Montana Gold on their mini's?
Theres a huge range of colours for that. Liquitex also offering their own range of sprays which looks interesting.

I prefer MTN Hardcore, and yes MTN is not Montana there's a long boring story behind it. Even though both make "gold" lines. MTN hardcore dried with a somewhat matte finish and has a thin-medium consistency. Where are Montana gold it pretty thick stuff. Most graffiti grade paints youll find will have a large selection of colors. Just be prepared to order extra fat caps along with them, they tend to clog up. Pink or orange dots should do the trick.

hmm
I have some montana gold at home... for other uses.... never tried it on a model, but i would be a little worried that it could be quite thick, i mean it covers walls very well, but with a quick spray you could get away with it

Solar Shock wrote:
hmm
I have some montana gold at home... for other uses.... never tried it on a model, but i would be a little worried that it could be quite thick, i mean it covers walls very well, but with a quick spray you could get away with it

I was never a fan of montana, it's a great quality paint but I didn't like gloss and I wanted drips so I always went with thinner matte paints. It did have some great colors in it's line though! The green (green apple or something) was always one of my favorites. It always had issues with clogging up though