Message Thread:
What ratio aaa pump?
12/14/16
Website: http://www.mcconnellfinefurniture.com
Hi, I am looking at purchasing a Graco Merkur ES for spraying solvent based PC and AC lacquer and paint. The thickest material that I spray is PC white primer. My question is which ratio pump should I get 15:1 or 30:1?
I am currently using a Fuji HVLP and while the finish is good, I find it agonisingly slow on the thicker material.
12/14/16 #2: What ratio aaa pump? ...
get the 15 to 1and since you're using catalyzed material make sure to get the stainess steel model.
12/15/16 #3: What ratio aaa pump? ...
I have the 15:1 ratio model and it's fine for the majority of water based products I spray. Heavier primers can be a challenge
12/15/16 #4: What ratio aaa pump? ...
Thanks for the replies!
Denny J do you have to thin the heavy primers a lot?
Nick, I didn't realise I'd need the stainless model for catalyzed material, thought that was for waterbased material?
Thanks again.
12/17/16 #5: What ratio aaa pump? ...
If you are going to use this pump as the "main" pump and spray all kinds of coatings with it, then I would think of it this way. Do you want a V6 or a V8? A V6 will move the car down the road and do everything you want,but the V8 can do it also and just not work as hard.
A 30:1 pump will cycle less, have less shear, it will push any coating you put in it and you could run two guns off of it if needed.
If money is an issue than the 15:1 is the choice, if not go to the 30:1
12/17/16 #6: What ratio aaa pump? ...
You don't have to thin them excessively but you do need to increase the air and fluid pressure and it works the pump harder which might make a bigger pump worthwhile if you spray a lot if that type of product.
The 15:1 pumps are wonderful for clears,stains and pigmented topcoats but thicker latex and some primers not so much. You could also get a dedicated airless for the thicker stuff.
12/17/16 #7: What ratio aaa pump? ...
Both Bob & Denny make good points. Bob has me pegged because I say 15-1 for the cost savings...Why spend it if you don't need to (that said I don't know what the price difference between the 2 is)? But then like Denny said I do have a little Titan 440 that I dust off a couple a times a year when somebody wants something sprayed with house paint.
12/18/16 #8: What ratio aaa pump? ...
Thanks for the further responses!
I had a rethink and decided against the mini merkur ES and have now purchased the merkur 30:1 25cc for the following reasons;
1)The deal I had on the ES was not for the stainless pump.
2)I didnt want to have any difficulty spraying primer which I use quite a bit of.
3)I'd rather spend a bit extra on a pump that will not have to work hard and consequently last longer hopefully.
Thanks again for all your guidance.
12/18/16 #9: What ratio aaa pump? ...
One question I have on the bigger 25-30:1 pumps-
How much additional air do they take to operate vs the 15:1 pumps? Is it as simple as it takes 2x the air per stroke to run them?
I know with my 15:1 Merkur and CAT units I can run them with a portable 30 gallon compressor and while it works hard it can be done. Some years back I had several kitchens to paint and I was running it off of a pancake compressor which is what the sales rep told me could be done. It wasn't ideal but it got the job done.
I would imagine that would not be possible with a 30:1 pump?
12/18/16 #10: What ratio aaa pump? ...
i am sorry i got late to this thread, a 30-1 is an overkill for wood coatings, and just because it is a 30-1 does not mean you are going to get more delivery, it depends on the gpm of the pump, don t ever buy a pump based on pressure, you need to consider delivery and that makes a difference whether you can run two guns or not
always consider the pressure needed to atomized your coatings, even the heavies primers will atomize with a 15 to one
good luck herb j
12/19/16 #11: What ratio aaa pump? ...
Re; air consumption
Graco has some graphs at the end of the technical data booklet that show the air consumption of both the 15:1 & 30:1.
What I understand from it is; It's more about what percent of the capabilities of the pump you're using then a straight across material psi/material volume pump to pump ratio.
What it boils down to is if you're spraying over 1,000 psi get the 30:1, since 1,000psi is only 1/3 the capability of the 30:1 it uses less air at this pressure (but just a bit) then the 15:1 as 1,000psi is 2/3 of the 15:1 capability so it's working harder.Or in other words if your spraying acrylic latex, DTM, alkyd acrylics or similar viscous material.at 1,000psi + through a .013 or a .015 get the 30:1 but if your spraying wood finishes at 600psi or less with a .011 or .013 the 15:1 is the pump to get.
12/19/16 #12: What ratio aaa pump? ...
Good points but wears a pump out is how many strokes it takes to keep up with delivery at a certain pressure. Ie the pump delivery
Also if you look at the size of the ball checks on lower pressure pumps they are typically larger than those of a higher pressure pump if the delivery gm is the same. Good discussion
Good luck herb j
12/19/16 #13: What ratio aaa pump? ...
You're right Herb These are small pumps meant for one gun and small tips. The only difference between the two is the ability of the 30:1 to spray at higher psi it does not offer a greater max material flow. Of course the thicker material that needs higher psi to atomize also needs larger tips to pass through which means more material, more pumping, more air & more wear.
Not to say the 30:1 will wear out in a blink of a eye...it's a Graco so no doubt a top-notch pump with easy to get parts. As a matter of fact I was all set to buy a 15:1 until I was offered a new Binks 412 at 1/2 the price of the Graco.
12/19/16 #14: What ratio aaa pump? ...
Lots to think about there...
I guess the 30:1 may be overkill for me but there is also the fluid flow to consider.
The mini Merkur ES has a volume of 6cc per cycle (30:1 and 15:1) so at a rate of 240 CPM it will deliver 1.5 litres per minute.
The larger Merkur I have ordered has a volume per cycle of 25cc so 1.5 litres per minute will require only 60 CPM.
I got this info from Graco's pump brochure.
Obviously the larger pump will require more air per cycle but the wear rate on the pump should be much lower as it only has to do 1/4 the cycles to deliver the same volume.
What this means in terms of overall air consumption I don't know and I hope my 16 cfm compressor can keep up!
I expect to have the new pump in the next couple of days so can let you know how I get on.
Thanks to all,
Ruairi
12/19/16 #15: What ratio aaa pump? ...
Everybody has good input. I suggest you do this, call the sales rep and have them bring a 15:1 demo pump to use for a week. Then swap it out for a 30:1 and then make up your mind. Run the hell out of the pump!! Just remember they can swap out fluid sections and air motors and build what you want also.
Trust me you will notice a difference.
12/20/16 #16: What ratio aaa pump? ...
in doing a little more research, the graco es looks to be a price point pump, to compete with other price ppoint pumps from other mfg
once you get above that level, their is a lot more parity in flow rate
12/20/16 #17: What ratio aaa pump? ...
That would be the ideal scenario Bob. Unfortunately not feasible for me, I live in Ireland and am getting the pump shipped to me from the UK.
12/21/16 #18: What ratio aaa pump? ...
As far as quality goes I have owned 3 different AAA units over the years. The first was an Asturo that was the first one to come off the ship from Italy in the late 90's or early 2000's that burned up in my first shop.
The second,which I still have is a cat and the latest which I have had for probably 5 or so years is a Merkur ES..
The Asturo was a fine unit for sure. The CAT seems to always need some part replaced including last week when I had to spend nearly $200 to buy the upgraded magnet assembly that was apparently a problem and had to be reengineered.
The Merkur is the quietest,has the best gun and I can't say anything about how it's put together because it's the only one I never have had to tear apart to fix.
The Cat is used nearly 100% for clears while the Merkur sprays pigmented water based products, primers, latex etc. I will not hesitate to buy another one.
12/22/16 #19: What ratio aaa pump? ...
it would be a good idea to have a rep. to demo the kremlin system. they set the standard for finishing in wood industry.
12/30/16 #20: What ratio aaa pump? ...
Ruairi,
I would say that from what you said your needs were that you made the right choice. With a 30:1 pump you can spray just about everything with no problems. The smaller pumps are not great for thicker materials, I have a Kremlin 30:1 pump and it is the best pump I have ever used by far. I always recommend to people though that the most important part about any tool or piece of equipment is service, if it breaks down or is not doing a good job, you need to have someone close by to resolve the problem. For me the best dealer and finishing rep is a Kremlin dealer, so that is what I use.
1/2/17 #21: What ratio aaa pump? ...
denny, i would contact ca tech directly, they do a no charge uprgrade in house colorado to the bobcat pump
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