Spray Gun Question.

[ayjay]

I have a small compressor - 1.25 hp, the output is 5cfm, I'd like to use this for spraying glaze but am struggling to decide on a gun.

 

In an ideal world I'd have a larger compressor but that's not going to happen yet.

 

I've found spray guns with a 1.8mm nozzle which requires 4.3cfm and another with a 1.5mm nozzle which requires 4.2 - 7.0 cfm and several with smaller nozzles at either 1.0mm or 0.8mm, one in particular of those last two only requires 1.6- 4.0 cfm.

 

Of the spray guns I've found, some are HVLP and some are LVLP, is one better than the other for glazing, and why?

 

I'm looking for the larger nozzles (1.5mm & 1.8mm)  because all that I've found on the net with regard to spraying glazes says that that's what's needed. 

 

I'm puzzled however as to why I would need that size nozzle.  If my glaze has been through a 100mesh sieve with a hole size of 0.152mm  why do I need such a large nozzle?

 

Next question, I've used the spray equipment at college and I know that I don't spray anything for more than a few seconds at a time, does this mean that I can use a gun with greater requirements than the compressor is capable of delivering if the gun was used constantly?

 

There is no Harbour Freight in the UK, so please don't send me there - but should I just buy the cheapest that seems closest to my requirements and give it a try?   It may be quicker in the long run, any detailed info on this is so hard to find.

[Marcia Selsor]

I got a Harbor Freight HVLP compressor with a spray gun. Unfortunately My nice adjustable spray gun that I used on my very old compressor will not hook up to the HVLP compressor setup. I had a Power pal from Sears about 20-30 years ago. It worked for my spray gun and air brush. It died finally. It was adjustable to 100 pounds pressure. For glazing I used 25 pounds pressure and air brushing, 15 psi. I prefer gravity fed for both air brushing and glaze spraying. The HVLP sprayer is a syphon sprayer. It works well, but I haven't completely adapted to it yet.

 

Marcia

[ayjay]

Thanks Marcia, my compressor goes up to 8 bar, or about 116 psi, so I don't think that will be a problem, and I can regulate the output to whatever I want up to that figure.

 

I'll try and condense my main concern into a couple of lines here and hopefully someone will know, (although I'm still puzzling over the nozzle size question):-

 

Can I successfully use a spray gun -  which has greater requirements than the compressor is capable of delivering if the gun was in use constantly  -  for a short period of time, say, 10 seconds at a time?

 

 

[Marcia Selsor]

I think that may be too intense and blow right off the pot. The best sprayer I have used for glaze is a simple EZ Sprayer syphon type that uses 25 PSI. The next good sprayer I have used is the one sold by Geil that is a gravity feed. The third is the HVLP syphon style from Harbor Freight. They all use about 25 psi. Actually can't say exactly what the Harbor freight is set for.

but it is High Volume , Low Pressure.

Marcia

[Denice]

I have owned a Webster Critter Sprayer around 15 years,  I don't think it was even call that back then.  It has been an great sprayer, never had to adjust or replace anything on it.  I have been using a really old sears small compressor that is about 50 years old that has no tank so it runs all the time also no pressure adjustment on it but it seems to be the right pressure.  We got a new compressor for X-Mass I'm anxious to try it,  I found the Critter Sprayer on-line for $55 so they are still being sold.  You might could hunt around and find one cheaper.  Happy Holidays        Denice

[ayjay]

I think that may be too intense and blow right off the pot. The best sprayer I have used for glaze is a simple EZ Sprayer syphon type that uses 25 PSI. The next good sprayer I have used is the one sold by Geil that is a gravity feed. The third is the HVLP syphon style from Harbor Freight. They all use about 25 psi. Actually can't say exactly what the Harbor freight is set for.

but it is High Volume , Low Pressure.

Marcia

 

It's not going to blow the glaze off the pot, I can regulate the output from the compressor to whatever psi is required - but as well as the correct pressure the gun will need a certain volume of air at that pressure.

 

What I'm trying to establish is, if the volume output of the compressor is below that required by the gun, how long will the gun operate correctly for? If I can get roughly ten seconds at a time I feel that that will be enough.

 

 

I have owned a Webster Critter Sprayer around 15 years,  I don't think it was even call that back then.  It has been an great sprayer, never had to adjust or replace anything on it.  I have been using a really old sears small compressor that is about 50 years old that has no tank so it runs all the time also no pressure adjustment on it but it seems to be the right pressure.  We got a new compressor for X-Mass I'm anxious to try it,  I found the Critter Sprayer on-line for $55 so they are still being sold.  You might could hunt around and find one cheaper.  Happy Holidays        Denice

 

Thanks Denice, I've seen the Critter sprayer mentioned several times, it may be available in the UK in one guise or other but doesn't seem to be called the same.

[Mark C.]

I suggest a gravity feed gun with reservoir on top these can be had cheaply mail order-there have been a few threads on them-search them out for the links.They do not need  a lot of pressure to work.

 

Found this link to those guns

http://www.tcpglobal.com/TCPG7000.html#.Ve54Sel41ww

Mark

[ayjay]

I suggest a gravity feed gun with reservoir on top these can be had cheaply mail order-there have been a few threads on them-search them out for the links.They do not need  a lot of pressure to work.

 

Found this link to those guns

http://www.tcpglobal.com/itemdetail.aspx?itemno=TCP%20G7000

Mark

Thanks Mark;  looking at the link, I see that those guns have nozzles/tips ranging from 1.0mm - 1.8 mm, and a requirement of between 3.0 and 7.1 cfm; do you think those nozzle sizes would all work for spraying glaze?

 

I'm particularly keen to keep the nozzle size as small as possible (0.8 or 1.0 would be good) as it seems the larger the nozzle the greater volume of air that's required.

 

The output of my compressor is only 5cfm, but I'm guessing that the stated requirement would be for continuous spraying which I see as an unlikely scenario.

 

Am I thinking about it too much? 

[Mark C.]

That link was for some guns that others really liked on this forum . I think your little compressor will work fine with a small canister spray gun

those 3 guns vary it says from 307 cfm so at least a few  of them will work.

This one on the Bailey site uses 4.2 CFM

http://www.baileypottery.com/sprayequip/bailyspraygun.htm

I think  you should look for a 1/4 inch inlet supply and small canister and you will be fine.

 

I use a tiny 3.5 amp (unknown cfms) compressor with a few small guns and they all work fine.

I only spray slips mostly with my salt pots I dip/brush work my production reduction wares.Spraying takes to long

Mark

[ChenowethArts]

I seem to collect spray guns but gravitate back to a very simple siphon tube sprayer available from Chick Tool Company: EZE TB-02P I think it runs about $30 (USD) but the plastic bottles are inexpensive, come with screw-on lids,  and are quite convenient to store pre-screened glaze (I screen mine to 100 mesh and have never had an issue).

 

Peace,

-Paul

[oldlady]

i like this sprayer for its simplicity and ease of use.  cleaning is just a matter of running water through the sprayer after each color change.  my only objection is to the bottles.  i have 24 or so of them and another 10 that are badly made and the tops do not fit.  if i put liquid in them, close the top, and shake, liquid goes all over the room.

[ayjay]

I seem to collect spray guns but gravitate back to a very simple siphon tube sprayer available from Chick Tool Company: EZE TB-02P I think it runs about $30 (USD) but the plastic bottles are inexpensive, come with screw-on lids,  and are quite convenient to store pre-screened glaze (I screen mine to 100 mesh and have never had an issue).

 

Peace,

-Paul

 

I've tried quite hard (previously) to find something similar in the UK without any success. I must resolve to start looking again.

 

My favourite air-brush works on exactly the same principle and very rarely clogs up, unlike the needle models which seem to clog up just for fun.

[MichaelP]

On 8/6/2016 at 1:15 PM, ChenowethArts said:

I seem to collect spray guns but gravitate back to a very simple siphon tube sprayer available from Chick Tool Company: EZE TB-02P I think it runs about $30 (USD) but the plastic bottles are inexpensive, come with screw-on lids,  and are quite convenient to store pre-screened glaze (I screen mine to 100 mesh and have never had an issue).

 

Peace,

-Paul

I followed your advice, Paul, and bought the gun (mine is TB-10P, but I don't know if it's different from TB-02P: still waiting for the reply from the manufacturer). What a pleasure to use it after all those HVLP guns!

What air pressure do you prefer for glaze spraying with this gun? I used 25-35psi, and it worked perfectly.  

Thank you.

Mike

P.S.  For the technically inclined. The gun comes with a quick air connector (male). For certain situations it is convenient, but in my case, I wanted to connect a pressure regulator directly to the gun and then use a quick disconnect between the regulator and air hose.  Unfortunately, it's not as simple as I expected.  After removal of the male connector, I noticed that the corresponding female thread in the gun is M10x1.0 (so an adapter is needed to connect M10x1.0 to the standard 1/4" NPT thread of the regulator).  Since it's not a tapered NPT thread, they had to use a rubber o-ring to prevent leaks.

On top of this, they use the same male connector to push/hold a compression spring for the trigger.  So the adapter will need to have an internal lip at a certain distance to press against the spring.  I don't yet know if such metric to NPT adapter has the lip, because the adapter itself, although in existence,  is not widely available. I can machine my own or modify a commercial one, of course, but it would be easier if they simply used the regular 1/4" NPT thread on the gun.  I suspect the Asian factory that produces the guns simply didn't bother and used a metric thread.