cubdriver2
FRIEND
upstate NY
Don't forget it should be a minimum of 25' from compressor to allow vapor to cool to a liquid
Glenn
Lowrider LSA
- Thread starter Lowrider
- Start date
Don't forget it should be a minimum of 25' from compressor to allow vapor to cool to a liquid
Glenn
Cub,
I'm not exactly sure but I'd guess at least 30 minutes. I had to stir and wait for the primer to run thru the strainer and I really wasn't in a hurry so it took awhile before I began to shoot. My shop is pretty dry and the primer dried quickly, but I suppose there could have been some moisture left behind...good thought.
Glenn,
Water catcher thingy is about 15' from the compressor and below the air outlet then there is another 15' to the gun. I've always tried to keep the hoses short to cut down on pressure loss. I've seen guys put the trap in ice to stop the moisture there and not let it get to the gun. Think that would help?
I have a 60 gal tank and I drain it before each use and I never seem to get water at the gun but that could happen I suppose. If that was causing the peel...wouldn't it be more apparent the further I go into the period of spraying?
I'm not exactly sure but I'd guess at least 30 minutes. I had to stir and wait for the primer to run thru the strainer and I really wasn't in a hurry so it took awhile before I began to shoot. My shop is pretty dry and the primer dried quickly, but I suppose there could have been some moisture left behind...good thought.
Glenn,
Water catcher thingy is about 15' from the compressor and below the air outlet then there is another 15' to the gun. I've always tried to keep the hoses short to cut down on pressure loss. I've seen guys put the trap in ice to stop the moisture there and not let it get to the gun. Think that would help?
I have a 60 gal tank and I drain it before each use and I never seem to get water at the gun but that could happen I suppose. If that was causing the peel...wouldn't it be more apparent the further I go into the period of spraying?
Bearhawk Builder
FRIEND
In the woods
Orange peel is not usually a contamination problem like fisheye, solvent popping or blushing, it's a film thickness / viscosity problem. The fact that you were getting orange peel on the first coat tells me you are loading way too much paint on. Pressure too low, paint too thick, wrong tip size, fan too tight, spray speed too slow, crappy gun. All of these will cause orange peel, in any paint by the way.
Something is wrong because every time I've used ecoprime I'm surprised at how smooth it lays down, one of the things I like about it.
Something is wrong because every time I've used ecoprime I'm surprised at how smooth it lays down, one of the things I like about it.
cubdriver2
FRIEND
upstate NY
Anything you can do to trap water helps on any airline
Glenn
Glenn
Longwinglover
Registered User
Charlotte, NC
Sounds like you need to replace leaky hoses? A longer run technically just increases the volme of higher pressure air - doesn't cause lower pressure.
Now, if you were painting with electricity, there would be line loss over a long run...
John Scott
Bearhawk,
I agree that could be the problem but wouldn't that mean the problem would be wide spread and not localized. Same gun and technique worked fine on most of the first coat and subsequent ones which led me to believe there is some contamination on the filler and not so much with the primer. Also, I shot a very nice 2'x3' pattern on card board to make sure the gun was set up OK.
Longwing,
I think air has friction in the hose the same as electricity has resistance in the conductor just like water in a pipe looses pressure over a long run. Not sure how a longer hose gives an increased volume.
Cub,
That's a good idea and easy to drain too.
I agree that could be the problem but wouldn't that mean the problem would be wide spread and not localized. Same gun and technique worked fine on most of the first coat and subsequent ones which led me to believe there is some contamination on the filler and not so much with the primer. Also, I shot a very nice 2'x3' pattern on card board to make sure the gun was set up OK.
Longwing,
I think air has friction in the hose the same as electricity has resistance in the conductor just like water in a pipe looses pressure over a long run. Not sure how a longer hose gives an increased volume.
Cub,
That's a good idea and easy to drain too.
Longwinglover
Registered User
Charlotte, NC
Not fightn' just discussin'
If you have a compressor with a 100 cubic foot tank filled to 100 PSI.
You disconnect the air line and installed a gauge in the line outlet. The gauge would read 100 PSI, right?
If you removed the gauge, reconnected the air line then installed the gauge at the far end of the line it would also read 100 PSI, right?
The tank has a 100CF volume. The air line has "X" volume (admittedly small). Your new volume is 100 + "X", right?
John Scott
I'll play...
You're right on the pressure.
Your 100 CF in the tank will be minus the volume of the hose unless the pump comes on to replace the air moved from the tank to the hose. Pressure at the end of the hose will be slightly less if the volume is reduced.
As you let air out of the tank without replacing it, the pressure will be reduced, albeit very slightly. IF you let out a lot of air and none is replaced then the pressure in the tank will be reduced by some percentage per cubic foot of air removed...but then I was dating a well endowed girl at the time and may have slept thru some portions of Fluid Dynamics class.
You're right on the pressure.
Your 100 CF in the tank will be minus the volume of the hose unless the pump comes on to replace the air moved from the tank to the hose. Pressure at the end of the hose will be slightly less if the volume is reduced.
As you let air out of the tank without replacing it, the pressure will be reduced, albeit very slightly. IF you let out a lot of air and none is replaced then the pressure in the tank will be reduced by some percentage per cubic foot of air removed...but then I was dating a well endowed girl at the time and may have slept thru some portions of Fluid Dynamics class.
Marty57
PATRON
Nipomo, Ca
What size hose and fittings are you running? We were told at the seminar to use 3/8" vs the standard 1/4" line. Another trick we learned was to cool the air to help take out the water vapor. A nice coil of copper tubing set inside a cooler with the water trap at the end of the coil seems to make a good and inexpensive cooler/dryer. Just passing on some of the tid-bits we learned in the seminar.
Marty57
Marty57
Hey Marty!
I'm using a 1/4" hose now but I'll buy a new 3/8" for finish painting. Sounds like the "learnin" you got at the seminar was worthwhile. It would be nice to suck some of that experience out of Dan's head for sure.
I have seen real painters use the ice bath thing in humid conditions and it certainly works. I like the way Glenn did the drain...maybe I could include a way to cool the tube into his design. When I was coating guns and sporting goods I used a 3/4" steel pipe system that was on a 10 degree slope up toward where I was picking up the air for the gun with a filter and trap before the hose and it worked really well. All the moisture drained back to the compressor and a drain point...might need to do something like that in this shop before I do any top coat finish painting.
I'm using a 1/4" hose now but I'll buy a new 3/8" for finish painting. Sounds like the "learnin" you got at the seminar was worthwhile. It would be nice to suck some of that experience out of Dan's head for sure.
I have seen real painters use the ice bath thing in humid conditions and it certainly works. I like the way Glenn did the drain...maybe I could include a way to cool the tube into his design. When I was coating guns and sporting goods I used a 3/4" steel pipe system that was on a 10 degree slope up toward where I was picking up the air for the gun with a filter and trap before the hose and it worked really well. All the moisture drained back to the compressor and a drain point...might need to do something like that in this shop before I do any top coat finish painting.
cubdriver2
FRIEND
upstate NY
5 gal bucket filled with water and a 25' coil of hose makes a cheap cooler. And any horizontal airline with a T with a 6" down drop with a dump valve gives moisture a place to settle before your airline
Glenn
Glenn
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Longwinglover
Registered User
Charlotte, NC
Hmmmm...
Never got much painting done with the compressor off.
Since the line is open to the tank, pressure in the line = pressure in the tank. If the compressor runs without you painting and fills the tank to 100PSI, the pressure in the line is 100PSI too. If you then turn the compressor off and start painting, pressure in the line will decrease in direct corrolation to pressure in the tank.
Of coures we haven't talked about the regulator in the line... Questions were about pressure and volume. LOL !!
John Scott
Never got much painting done with the compressor off.
Since the line is open to the tank, pressure in the line = pressure in the tank. If the compressor runs without you painting and fills the tank to 100PSI, the pressure in the line is 100PSI too. If you then turn the compressor off and start painting, pressure in the line will decrease in direct corrolation to pressure in the tank.
Of coures we haven't talked about the regulator in the line... Questions were about pressure and volume. LOL !!
John Scott
cubdriver2
FRIEND
upstate NY
I think the old plumbers rule was double the pipe size is quadruple the volume? More volume in hose = less pressure drop at end of hose. Take an air impact gun and run on 1/4 hose and then on 3/8 hose and see how much more power it has.
Glenn
Glenn
knucles
Registered User
nevada
I can see that MARTY57 paid attention in the class. But I also saw it in his working sample....
we spend a lot of time and money on our projects . I think the small amount of time and cost to learn the system you are using and the excellent tips that the books do not show , are well worth it and it shows in your work.
we spend a lot of time and money on our projects . I think the small amount of time and cost to learn the system you are using and the excellent tips that the books do not show , are well worth it and it shows in your work.
Cub,
The bucket trick is a good and easy idea...thanks! You're right about larger hose too. You guys are full of ideas!!
John,
You're right too. Guess the "regulator" is an in-line valve to keep pressure consistent at the gun. I use high pressure out of the tank and reduced air at the gun so the compressor can cycle on and off and still maintain desired pressure at the gun.
The bucket trick is a good and easy idea...thanks! You're right about larger hose too. You guys are full of ideas!!
John,
You're right too. Guess the "regulator" is an in-line valve to keep pressure consistent at the gun. I use high pressure out of the tank and reduced air at the gun so the compressor can cycle on and off and still maintain desired pressure at the gun.
Knucles,
Guess you attended too. The little things the knowledgeable folk take for granted are hard learned by the rest of us so it's certainly worthwhile to learn it the easier way. Someone at Stewart's said the hardest people to teach are the one's who think they know how it's done and have extensive experience with a spray gun...I think they're right.
Guess you attended too. The little things the knowledgeable folk take for granted are hard learned by the rest of us so it's certainly worthwhile to learn it the easier way. Someone at Stewart's said the hardest people to teach are the one's who think they know how it's done and have extensive experience with a spray gun...I think they're right.
knucles
Registered User
nevada
I have purchased the rotec throttle body as well . I am confident that it will work fine. I checked with a couple of others that were already using it. They were happy.
I wanted this for a few reasons , to get away from a carb , I did not want to have a donkey dick hanging under my cowl , my air intake will not be under the cowl , I can mount in any position or location , cost to purchase is respectable and I love using stuff that certified aircraft can not use.
I wanted this for a few reasons , to get away from a carb , I did not want to have a donkey dick hanging under my cowl , my air intake will not be under the cowl , I can mount in any position or location , cost to purchase is respectable and I love using stuff that certified aircraft can not use.
WWeldon
Registered User
Chugiak, Alaska
Unless you are not using a regulator to control your line pressure the tank pressure should be much higher, my tank runs at 150 lbs and line pressure I set at 95# line pressure at the regulator, the tank pressure switch comes on way before the tank approaches line pressure. If you have a proper sized and regulated system then you should never have a fluctuation in line pressure. I have 35 year experience shooting Nitro Cellulose lacquer and every catalyzed finish marketed since 1976 and I have never run a gun or any other air tool for that matter without a regulator. The exception being HVLP which is a different animal all together . I currently run both in an explosion proof spray booth.Hmmmm...
Never got much painting done with the compressor off.
Since the line is open to the tank, pressure in the line = pressure in the tank. If the compressor runs without you painting and fills the tank to 100PSI, the pressure in the line is 100PSI too. If you then turn the compressor off and start painting, pressure in the line will decrease in direct corrolation to pressure in the tank.
Of coures we haven't talked about the regulator in the line... Questions were about pressure and volume. LOL !!
John Scott
I'm doing the nose bowl that way too and #2 son has a plan for a carbon fiber lower cowl but I'm not wild about his ideas yet. I am playing with the idea of lower cowl that will blend smoothly with the belly and direct exhaust along the sides mixed with most airflow. I was going to try and fair the cabane and main legs into the design but it's not working for me. More thought I suppose.
My carb is sold if anyone else is interested.
Took a drive to Kootenay Bay in beautiful British Columbia today and I can highly recommend a visit there since it is in fact a beautiful spot. The mountains were hidden some by fog and clouds but that just made it all the better. The lake was glass smooth in most places and made for beautiful reflections. Temps were in the mid 50's with some light rain so Spring is coming to the area. I did find out that I can't make my planned canoe trip down the Kootenai River from the US into Canada since there is no crossing allow there any more. I promised not to smuggle anything into Canada and that I wasn't a terrorist and Canadian custom would have nothing of it...seems you can fly or drive into Canada but not by boat...very disappointing for sure!!
Took a drive to Kootenay Bay in beautiful British Columbia today and I can highly recommend a visit there since it is in fact a beautiful spot. The mountains were hidden some by fog and clouds but that just made it all the better. The lake was glass smooth in most places and made for beautiful reflections. Temps were in the mid 50's with some light rain so Spring is coming to the area. I did find out that I can't make my planned canoe trip down the Kootenai River from the US into Canada since there is no crossing allow there any more. I promised not to smuggle anything into Canada and that I wasn't a terrorist and Canadian custom would have nothing of it...seems you can fly or drive into Canada but not by boat...very disappointing for sure!!
Well, after the challenges I had on priming the fabric on the tail feathers, I rolled the fuselage outside today for a nice 65F day and I primed the fuselage tubing. Same gun, hose, compressor and so on and this time the Ecoprime went on as smooth as silk and was dried almost as quick as I shot it. A light breeze and 30% humidity helped with the drying. It went on so nice that I'm thinking of a second coat...just kidding!
Spring bear starts in a couple weeks so I checked out one of my little bear guns...Remington Model 7 in .260 on my 100 yd range...5 shots that could be covered with a silver dollar if I could find one. If I miss, it's not the gun's fault. My little bit bigger bear gun, Tikka in .338 Federal did better than the Remington and put three rounds just where I wanted them...could just about cover the 3 shots with a beer bottle cap...not that I drink beer.
Fishing, hunting and dirt bike riding is coming up soon and will provide distractions from airplane building, but I will try to put in at least one hour per day on the plane. I'm scheduled to take the Lowrider out for a few runs into Canada, eh, and maybe Montana/Wyoming for a bit as well so if I'm not here, I'm somewhere else. All 3 sons will be here this Summer so I guess I need to make time for them too...not to mention travelers from the East and South...might even do some flying.
Highly recommend the Ecoprime NOW. My bet is still there was contamination on the Ecofill...but I'm learning!!
Spring bear starts in a couple weeks so I checked out one of my little bear guns...Remington Model 7 in .260 on my 100 yd range...5 shots that could be covered with a silver dollar if I could find one. If I miss, it's not the gun's fault. My little bit bigger bear gun, Tikka in .338 Federal did better than the Remington and put three rounds just where I wanted them...could just about cover the 3 shots with a beer bottle cap...not that I drink beer.
Fishing, hunting and dirt bike riding is coming up soon and will provide distractions from airplane building, but I will try to put in at least one hour per day on the plane. I'm scheduled to take the Lowrider out for a few runs into Canada, eh, and maybe Montana/Wyoming for a bit as well so if I'm not here, I'm somewhere else. All 3 sons will be here this Summer so I guess I need to make time for them too...not to mention travelers from the East and South...might even do some flying.
Highly recommend the Ecoprime NOW. My bet is still there was contamination on the Ecofill...but I'm learning!!
I looked on the web site but can't find the life of EcoPoly Premium once opened but not mixed. I'd like to top coat most of my fuselage and the tail feathers and I'm not sure of a quart is going to do it and if I buy a gallon I don't want it to go bad before I'm ready to finish the remainder of the plane....maybe 8=12 months away.
Any thoughts from you Stewart's experts?
Any thoughts from you Stewart's experts?
Bearhawk Builder
FRIEND
In the woods
No expert but it's not air activated so you can just close it back up. Keep it cool, in the fridge next to the beer and it will last longer.
Bearhawk Builder
FRIEND
In the woods
I've used it up to a year old but fresh is better so I would order by the quart. Get enough for the job but not too much at a time.
