This is the first time I've tried to spray shellac. It was bullseye, out of
the can, and I cut it with denatured alcohol. I sprayed it, and it looked
ok at first, but as it dried, it seemed to pucker in spots and give me
orange peel. It's acting like I put it on too thick, but when i tried to
lay it on thinner, it didn't seem to be atomizing correctly, and it went on
a bit spotty. I put it on heavier to make it flow, but then it didn't seem
to dry right. What did I do wrong? Not thin enough?
Mark,
I sprayed the same shelac a few weeks ago. I used my latex tip and did not
thin it and only got a real fine orange peel - overall a nice finish. I am
going to thin it a little next time.
P.S. You can buy extra tip kits on ebay for much less than the other
sources.
Good luck,
AZCRAIG
www.azcraig.us
"mark" <[email protected]> wrote in message
news:[email protected]...
> This is the first time I've tried to spray shellac. It was bullseye, out
> of the can, and I cut it with denatured alcohol. I sprayed it, and it
> looked ok at first, but as it dried, it seemed to pucker in spots and give
> me orange peel. It's acting like I put it on too thick, but when i tried
> to lay it on thinner, it didn't seem to be atomizing correctly, and it
> went on a bit spotty. I put it on heavier to make it flow, but then it
> didn't seem to dry right. What did I do wrong? Not thin enough?
>
What make HVLP are you using? This sounds like gun/turbine problems.
--
Rumpty
Radial Arm Saw Forum: http://forums.delphiforums.com/woodbutcher/start
- - - - - - - - - - - - - - - - - - - - -
"mark" <[email protected]> wrote in message
news:[email protected]...
> This is the first time I've tried to spray shellac. It was bullseye, out
of
> the can, and I cut it with denatured alcohol. I sprayed it, and it looked
> ok at first, but as it dried, it seemed to pucker in spots and give me
> orange peel. It's acting like I put it on too thick, but when i tried to
> lay it on thinner, it didn't seem to be atomizing correctly, and it went
on
> a bit spotty. I put it on heavier to make it flow, but then it didn't
seem
> to dry right. What did I do wrong? Not thin enough?
>
>
Hi Mark,
If you have to put it on thick to make it flow makes me think that you are not
atomizing the material well enough. So try it with more atomization pressure. If
this does not do the trick, thin it more. I find that even with a crappy gun I
can spray a 1.5 lb cut with no problem. Good luck, JG
mark wrote:
> This is the first time I've tried to spray shellac. It was bullseye, out of
> the can, and I cut it with denatured alcohol. I sprayed it, and it looked
> ok at first, but as it dried, it seemed to pucker in spots and give me
> orange peel. It's acting like I put it on too thick, but when i tried to
> lay it on thinner, it didn't seem to be atomizing correctly, and it went on
> a bit spotty. I put it on heavier to make it flow, but then it didn't seem
> to dry right. What did I do wrong? Not thin enough?
"Rumpty" <[email protected]> wrote in message
news:[email protected]...
> What make HVLP are you using? This sounds like gun/turbine problems.
porter cable conversion gun. Seems to work fine on lacquer, but that's all
I've ever sprayed with it.
Don't know a lot about the subject but in my experience with sprayed
finishes, when I've gotten orange peel, too high viscosity was the problem.
bob g.
MikeG wrote:
> In article <[email protected]>,
> [email protected] says...
>
>>This is the first time I've tried to spray shellac. It was bullseye, out of
>>the can, and I cut it with denatured alcohol. I sprayed it, and it looked
>>ok at first, but as it dried, it seemed to pucker in spots and give me
>>orange peel. It's acting like I put it on too thick, but when i tried to
>>lay it on thinner, it didn't seem to be atomizing correctly, and it went on
>>a bit spotty. I put it on heavier to make it flow, but then it didn't seem
>>to dry right. What did I do wrong? Not thin enough?
>>
>>
>>
>
>
> First thing to do is to dump the idea that there is something wrong with
> the unit. It'll save you some time.
>
> Next thing to do is to get the viscosity cup recommended by the maker.
> Ford, Zhan then contact the maker to get an idea of what should flow out
> of the cup and recommended needle/nozzle combination.
>
> What you could be doing wrong could be not spraying the right viscosity
> for the needle/nozzle combination, to much air pressure, to little air
> pressure, too much air volume, too little air volume, incorrect fluid
> flow, needle set too far out from the nozzle, needle set too far into
> the nozzle, or any combination of the above.
>
> It's unlikely that even a three pound cut of shellac would need thinning
> but with the viscosity cup you will at least have an idea of where to
> start. If you know you have the right viscosity and needle/nozzle
> combination all you have to do is play with the air volume and fluid
> flow and needle set.
>
> The alternative is playing with all the factors in the rather large
> number of combinations they present.In other words without at least some
> fact based info you are just pissing in the dark.
>
>
>
>
Two possible causes: shellac needs more thinning for your
gun/tip/pressure combo. You are spraying from too far away, allowing
the shellac to dry before it hits the surface. Practice makes perfect.
Try altering your technique. What size tip are you using?
David
mark wrote:
> This is the first time I've tried to spray shellac. It was bullseye, out of
> the can, and I cut it with denatured alcohol. I sprayed it, and it looked
> ok at first, but as it dried, it seemed to pucker in spots and give me
> orange peel. It's acting like I put it on too thick, but when i tried to
> lay it on thinner, it didn't seem to be atomizing correctly, and it went on
> a bit spotty. I put it on heavier to make it flow, but then it didn't seem
> to dry right. What did I do wrong? Not thin enough?
>
>
In article <[email protected]>,
[email protected] says...
> This is the first time I've tried to spray shellac. It was bullseye, out of
> the can, and I cut it with denatured alcohol. I sprayed it, and it looked
> ok at first, but as it dried, it seemed to pucker in spots and give me
> orange peel. It's acting like I put it on too thick, but when i tried to
> lay it on thinner, it didn't seem to be atomizing correctly, and it went on
> a bit spotty. I put it on heavier to make it flow, but then it didn't seem
> to dry right. What did I do wrong? Not thin enough?
>
>
>
First thing to do is to dump the idea that there is something wrong with
the unit. It'll save you some time.
Next thing to do is to get the viscosity cup recommended by the maker.
Ford, Zhan then contact the maker to get an idea of what should flow out
of the cup and recommended needle/nozzle combination.
What you could be doing wrong could be not spraying the right viscosity
for the needle/nozzle combination, to much air pressure, to little air
pressure, too much air volume, too little air volume, incorrect fluid
flow, needle set too far out from the nozzle, needle set too far into
the nozzle, or any combination of the above.
It's unlikely that even a three pound cut of shellac would need thinning
but with the viscosity cup you will at least have an idea of where to
start. If you know you have the right viscosity and needle/nozzle
combination all you have to do is play with the air volume and fluid
flow and needle set.
The alternative is playing with all the factors in the rather large
number of combinations they present.In other words without at least some
fact based info you are just pissing in the dark.
--
MikeG
Heirloom Woods
www.heirloom-woods.net
[email protected]
>First thing to do is to dump the idea that there is something wrong with
the unit. It'll save you some time.
Cheap low quality HVLP conversion systems can be the cause of a lot of
problems with product applications. That is why the question was asked.
--
Rumpty
Radial Arm Saw Forum: http://forums.delphiforums.com/woodbutcher/start
- - - - - - - - - - - - - - - - - - - - -
"MikeG" <[email protected]> wrote in message
news:[email protected]...
> In article <[email protected]>,
> [email protected] says...
> > This is the first time I've tried to spray shellac. It was bullseye,
out of
> > the can, and I cut it with denatured alcohol. I sprayed it, and it
looked
> > ok at first, but as it dried, it seemed to pucker in spots and give me
> > orange peel. It's acting like I put it on too thick, but when i tried
to
> > lay it on thinner, it didn't seem to be atomizing correctly, and it went
on
> > a bit spotty. I put it on heavier to make it flow, but then it didn't
seem
> > to dry right. What did I do wrong? Not thin enough?
> >
> >
> >
>
> First thing to do is to dump the idea that there is something wrong with
> the unit. It'll save you some time.
>
> Next thing to do is to get the viscosity cup recommended by the maker.
> Ford, Zhan then contact the maker to get an idea of what should flow out
> of the cup and recommended needle/nozzle combination.
>
> What you could be doing wrong could be not spraying the right viscosity
> for the needle/nozzle combination, to much air pressure, to little air
> pressure, too much air volume, too little air volume, incorrect fluid
> flow, needle set too far out from the nozzle, needle set too far into
> the nozzle, or any combination of the above.
>
> It's unlikely that even a three pound cut of shellac would need thinning
> but with the viscosity cup you will at least have an idea of where to
> start. If you know you have the right viscosity and needle/nozzle
> combination all you have to do is play with the air volume and fluid
> flow and needle set.
>
> The alternative is playing with all the factors in the rather large
> number of combinations they present.In other words without at least some
> fact based info you are just pissing in the dark.
>
>
>
>
> --
> MikeG
> Heirloom Woods
> www.heirloom-woods.net
> [email protected]
http://www.shellac.net/ShellacPricing.html
Look for shellac retarder on this page. It may help you with your
problem.
On Sun, 31 Oct 2004 01:29:27 GMT, "mark" <[email protected]> wrote:
>This is the first time I've tried to spray shellac. It was bullseye, out of
>the can, and I cut it with denatured alcohol. I sprayed it, and it looked
>ok at first, but as it dried, it seemed to pucker in spots and give me
>orange peel. It's acting like I put it on too thick, but when i tried to
>lay it on thinner, it didn't seem to be atomizing correctly, and it went on
>a bit spotty. I put it on heavier to make it flow, but then it didn't seem
>to dry right. What did I do wrong? Not thin enough?
>
"mark" <[email protected]> wrote in message
news:[email protected]...
>
> > This just about covers everything that *could* possibly be wrong, so it
> > really doesn't narrow things down for the OP. If there's orange peel
then
> > the only reason for that is a first coat that is too dry followed by
> > wetter
> > coats that the sprayer attempts to flow on. That's what creates the
> > orange
> > peel - subsequent coats bridge the spotty coverage of a dry coat and
> > create
> > the humps we call orange peel. You can't fill enough with additional
> > coats
> > and it will always look worse after it dries than it does when it's wet.
>
> Thanks for that mike. I printed it out, and will get to the bottom of it
by
> trying some of the tests you recommended. It seems like you are right --
it
> went on too dry at first, and then didn't flow out correctly. It's a
panel
> door that I'm spraying, so it has a lot of nooks and crannies that are
hard
> to get evenly.
>
>
It's like anything else - practice makes perfect. Well... perfect practice
makes perfect. I should have mentioned in the my post - and in fact David
did mention - watch your distance. Try to stay within 6" of your workpiece.
Spray from too far away and the atomized spray goes on dry. Experiment with
the direction you point your gun. When you're going down the length of the
door you can spray in-to-out a bit so that you get a good coverage on the
edge treatment of the panels and the styles and rails. You'll get it - just
keep working at it.
--
-Mike-
[email protected]
"MikeG" <[email protected]> wrote in message
news:[email protected]...
> In article <[email protected]>,
> [email protected] says...
> > This is the first time I've tried to spray shellac. It was bullseye,
out of
> > the can, and I cut it with denatured alcohol. I sprayed it, and it
looked
> > ok at first, but as it dried, it seemed to pucker in spots and give me
> > orange peel. It's acting like I put it on too thick, but when i tried
to
> > lay it on thinner, it didn't seem to be atomizing correctly, and it went
on
> > a bit spotty. I put it on heavier to make it flow, but then it didn't
seem
> > to dry right. What did I do wrong? Not thin enough?
> >
>
> What you could be doing wrong could be not spraying the right viscosity
> for the needle/nozzle combination, to much air pressure, to little air
> pressure, too much air volume, too little air volume, incorrect fluid
> flow, needle set too far out from the nozzle, needle set too far into
> the nozzle, or any combination of the above.
This just about covers everything that *could* possibly be wrong, so it
really doesn't narrow things down for the OP. If there's orange peel then
the only reason for that is a first coat that is too dry followed by wetter
coats that the sprayer attempts to flow on. That's what creates the orange
peel - subsequent coats bridge the spotty coverage of a dry coat and create
the humps we call orange peel. You can't fill enough with additional coats
and it will always look worse after it dries than it does when it's wet.
Thinning the fluid should be per the manufacturer's spec. It's usually ok
to thin a bit more if the gun does not seem to spray it freely, but
generally starting with manufacturer's spec is a very safe starting point.
Air flow, pressure, etc. are easily adjusted by shooting at a scrap and
adjusting to get a good fan and a good coverage. You should easily be able
to flow enough to cause a run if you just hold the gun in one place. Spray
with a slow, steady pattern, just overlapping each pass. You should imagine
that you're stretching a thin film of that clear stuff that wives keep in
the kitchen cupboard and that *only* wives can properly stretch over a bowl
of leftovers, over your workpiece. One pass on an area. One pass. Not
two. Not a little touch up. One pass. End to end. Watch your flow as
you're laying it down. You'll see if it's going on too heavy. You want to
see it flow on. Let it tack up per the manufacturer's spec between coats.
No shortcuts here. Smoke a cigarette, load the woodstove, instruct the wife
in the art of changing car tires - whatever is necessary to distract you
while you give that coat the required flash time. Then you can put on
another coat.
Flash times and dry times are going to be affected by temperature and
humidity, as well as how thick the coats are. A good wet coat is thicker
than a dry coat, but not so thick that you should see protracted dry times.
It's not that you're trying to put it on thick, you're trying to put it on
wet. Keep that though in your mind. Remember the plastic wrap idea.
Most folks make the mistake of spraying too fast as they fear runs. Spray
too fast and you get dry coats which result in orange peel. It sands out,
so it's not the end of the world, but it is extra work.
>
> It's unlikely that even a three pound cut of shellac would need thinning
> but with the viscosity cup you will at least have an idea of where to
> start. If you know you have the right viscosity and needle/nozzle
> combination all you have to do is play with the air volume and fluid
> flow and needle set.
Agreed the viscosity cup can be helpful, but the same can be achieved by
spraying at a scrap target and observing the fan. It's all a matter of what
makes you comfortable. I wouldn't want the extra step of the viscocity cup,
but others may well prefer to go that route.
>
> The alternative is playing with all the factors in the rather large
> number of combinations they present.In other words without at least some
> fact based info you are just pissing in the dark.
Not really. Again, you have the starting point defined by the manufacturer.
Thin to that point and start spraying on a scrap. Adjust the gun and tackle
the workpiece. There is no shooting in the dark, pissing in the dark - (by
the way... if you're going to piss in the dark always make sure you know
where the electrical outlets are), it's just a simple matter of setting up
the gun. That's something you have to do anyway.
--
-Mike-
[email protected]
> This just about covers everything that *could* possibly be wrong, so it
> really doesn't narrow things down for the OP. If there's orange peel then
> the only reason for that is a first coat that is too dry followed by
> wetter
> coats that the sprayer attempts to flow on. That's what creates the
> orange
> peel - subsequent coats bridge the spotty coverage of a dry coat and
> create
> the humps we call orange peel. You can't fill enough with additional
> coats
> and it will always look worse after it dries than it does when it's wet.
Thanks for that mike. I printed it out, and will get to the bottom of it by
trying some of the tests you recommended. It seems like you are right -- it
went on too dry at first, and then didn't flow out correctly. It's a panel
door that I'm spraying, so it has a lot of nooks and crannies that are hard
to get evenly.
Excellent advice for the OP, Mike. Much more focused response than some
of the others who prefer the "shotgun approach".
David
Mike Marlow wrote:
> "MikeG" <[email protected]> wrote in message
> news:[email protected]...
>
>>In article <[email protected]>,
>>[email protected] says...
>>
>>>This is the first time I've tried to spray shellac. It was bullseye,
>
> out of
>
>>>the can, and I cut it with denatured alcohol. I sprayed it, and it
>
> looked
>
>>>ok at first, but as it dried, it seemed to pucker in spots and give me
>>>orange peel. It's acting like I put it on too thick, but when i tried
>
> to
>
>>>lay it on thinner, it didn't seem to be atomizing correctly, and it went
>
> on
>
>>>a bit spotty. I put it on heavier to make it flow, but then it didn't
>
> seem
>
>>>to dry right. What did I do wrong? Not thin enough?
>>>
>
>
>>What you could be doing wrong could be not spraying the right viscosity
>>for the needle/nozzle combination, to much air pressure, to little air
>>pressure, too much air volume, too little air volume, incorrect fluid
>>flow, needle set too far out from the nozzle, needle set too far into
>>the nozzle, or any combination of the above.
>
>
> This just about covers everything that *could* possibly be wrong, so it
> really doesn't narrow things down for the OP. If there's orange peel then
> the only reason for that is a first coat that is too dry followed by wetter
> coats that the sprayer attempts to flow on. That's what creates the orange
> peel - subsequent coats bridge the spotty coverage of a dry coat and create
> the humps we call orange peel. You can't fill enough with additional coats
> and it will always look worse after it dries than it does when it's wet.
>
> Thinning the fluid should be per the manufacturer's spec. It's usually ok
> to thin a bit more if the gun does not seem to spray it freely, but
> generally starting with manufacturer's spec is a very safe starting point.
> Air flow, pressure, etc. are easily adjusted by shooting at a scrap and
> adjusting to get a good fan and a good coverage. You should easily be able
> to flow enough to cause a run if you just hold the gun in one place. Spray
> with a slow, steady pattern, just overlapping each pass. You should imagine
> that you're stretching a thin film of that clear stuff that wives keep in
> the kitchen cupboard and that *only* wives can properly stretch over a bowl
> of leftovers, over your workpiece. One pass on an area. One pass. Not
> two. Not a little touch up. One pass. End to end. Watch your flow as
> you're laying it down. You'll see if it's going on too heavy. You want to
> see it flow on. Let it tack up per the manufacturer's spec between coats.
> No shortcuts here. Smoke a cigarette, load the woodstove, instruct the wife
> in the art of changing car tires - whatever is necessary to distract you
> while you give that coat the required flash time. Then you can put on
> another coat.
>
> Flash times and dry times are going to be affected by temperature and
> humidity, as well as how thick the coats are. A good wet coat is thicker
> than a dry coat, but not so thick that you should see protracted dry times.
> It's not that you're trying to put it on thick, you're trying to put it on
> wet. Keep that though in your mind. Remember the plastic wrap idea.
>
> Most folks make the mistake of spraying too fast as they fear runs. Spray
> too fast and you get dry coats which result in orange peel. It sands out,
> so it's not the end of the world, but it is extra work.
>
>
>>It's unlikely that even a three pound cut of shellac would need thinning
>>but with the viscosity cup you will at least have an idea of where to
>>start. If you know you have the right viscosity and needle/nozzle
>>combination all you have to do is play with the air volume and fluid
>>flow and needle set.
>
>
> Agreed the viscosity cup can be helpful, but the same can be achieved by
> spraying at a scrap target and observing the fan. It's all a matter of what
> makes you comfortable. I wouldn't want the extra step of the viscocity cup,
> but others may well prefer to go that route.
>
>
>>The alternative is playing with all the factors in the rather large
>>number of combinations they present.In other words without at least some
>>fact based info you are just pissing in the dark.
>
>
> Not really. Again, you have the starting point defined by the manufacturer.
> Thin to that point and start spraying on a scrap. Adjust the gun and tackle
> the workpiece. There is no shooting in the dark, pissing in the dark - (by
> the way... if you're going to piss in the dark always make sure you know
> where the electrical outlets are), it's just a simple matter of setting up
> the gun. That's something you have to do anyway.
>
>