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screen printing => Equipment => Topic started by: Shanarchy on October 01, 2013, 09:17:42 AM
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What are the big differences, pros and cons, of a pneumatic indexer vs servo indexer, and pneumatic heads vs ac heads. I had an Anatol Horizon, all pneumatic, but I have no experience with the latter. I'm starting my quest for another automatic.
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I've only ever had servo/ac, but I can say that if it came down to it I'd take ac heads and air index over the opposite.
Air heads can be jumpy, which typically doesn't matter, but with AC you can plow through the thickest inks with ease.
An indexer is just that. Servo will be faster and smoother, but pneumatic will get the job done as well.
Pneumatic will require more air and more maintenance, but if anything on a servo goes you're in for some $$$.
So in short, aim for servo/ac. If not, pneumatic/ac, if anyone actually makes that.
Quality work is done on everything from Challenger 3's to Jiffy Clamps and wood frames. I even remember Mr. Hood
exalting a printer in India using handstretched screens and homemade emulsion, yet chastising those of us in the US
that would think of anything other than Newmans.
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I've only used air, unless you count the electric head on the old flat stock presses. Done right, as in the chopper and stroke cyls have sufficient bore and other characteristics beyond my knowledge of pneumatics, I don't think they could be a whole lot worse than an electric head. If under spec'd they will stall out at too fast a stroke speed, chatter and slam into their stops flangin' ink all over the place. Spec'd correctly I bet you could overcome all that. A brand new press with air heads might be just fine.
My question is why bother with the air? You'll save $ on the initial purchase (pneumatics being cheaper than AC motors, etc.) but will need a serious dryer/chiller combo and who knows if that savings really means much after you add up the electricity used to compress the air to operate the press. I would imagine it's even stevens on long term costs between the two. Or maybe in favor of air machines if your shop has copious compressed air already available. If that's true, there's no reason not to get AC heads. It's much easier to control something electric on drive system, no brainer there in terms of ease of use and consistency in real life operating conditions. Going new or given any option I'd take the electric up front.
Man, I totally agree, presses should have pneumatic index and AC heads rather than the other way around. I think you see it the other way around b/c you can streamline mfg of a machine if all the units have the same servo driven base. Pneumatic index can be annoying but it does work fine and, if you take the time to really dial it in for the exact platens you are using can be very fast. Downside of air index is that if you don't keep it dialed you'll prematurely wear the bearings and forks and need a re-registration sooner than you should.
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Funny that both of you mentioned you'd rather have a press with air index and AC heads rather than the other way around that you see most typically because I have felt that way for a long time but haven't heard anyone else mention it. I have brought it up in the past and I think someone in the know responded as to why you see so many servo driven/air print head machines. I can't say much of anything more than EB and Zoo said, those too are my thoughts on the matter. I know air print heads are used by thousands of shops every day with great success, but I'd always pay extra for AC heads if I have the chance. The few presses that I've been around that were air heads, it seems like the likelyhood of double stroking is far higher due to the inconsistent speeds. When the speed changes the edge of the squeegee likely changes very slightly but enough to prevent some ink from shearing from the stencil therefore needing the second print stroke. We all know air gets the job done, but AC gets it done faster. Not necessarily better but definitely faster, and a good bit more quiet.
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AC heads are FAR superior! Many reasons. If you can afford AC heads....do it!
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So my first auto press was a v-squeegee all air tuff freedom press. Since that press I've had nothing but m&r machines which have ranged from all air to servo index/air heads, to our latest ch3 press which is all a/c. I agree with what has been said for the most part and that's the fact that almost any machine in the right hands can achieve the same print regardless of air vs a/c. I've done some incredible looking prints on all air presses that imo would not have improved on an electric machine. Now if your a shop doing lots of 4cp and sim process I would strongly suggest a/c heads for the pure reason of consistency as well as the digital readouts so you can measure the speed of the stroke. With air head machines this is one downer imo but as far as quality of prints don't let anyone trick you into believing an a/c head/servo machine can bang out much better prints....From my experience with the 5 autos I've personally had this has never been the case. Now would I ever go back to a machine that was air? Heck no, our all a/c machine runs super smooth, not near as noisey and we never have issues with air supply which we did with our air machines. Like Alan said, a/c is faster which in some shops like ours is a big deal. When we get busy we are slammed with little to no down time and when we can print faster it really helps us out. More then anything I think having an index system like a ch3 or the new press m&r is releasing that dirk is getting imo is a better benefit then anything. The fact we can leave screens on the press after a job is completed, setup the next job and not worry about getting ink from the previous job on shirts is a huge time savings for us. The fact we can double stroke jobs @ 65 doz/hr and run single stroke jobs @ 90+ doz/hr has made me a firm believer in the ch3 indexing system. I will say our next auto will be another ch3 or this new sporty for the pure fact of the indexing system. We like the system that much! If you can swing a/c heads and servo index I would strongly suggest it. Will it be a make or break deal, no but it sure is "nice"
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we can double stroke jobs @ 65 doz/hr
This right here is probably the most impressive thing about an M&R press I've ever heard. That would be an insane benefit to waterbased and discharge printers like us. Also one area where air will work but, not as well- the up/down tabling is just plain slow.
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Its so crazy this was posted I was just talking about this. Good question
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The difference is well worth it. I think A LOT of people end up with all air presses because that is the cheapest way to go. Which if it is your first press is fair enough. I remember buying our first auto, all the sales guys were trying to push the ac heads, I just didn't understand how different things were until I got a press with ac heads.
Sometimes for us(up north where it gets cold) in the winter white ink with pneumatic heads would suck to print in the morning. Our shop would get as low as 40 at times over night, and that ink was like concrete. The ac heads just kinda power through it either way. There is more even and exact control with the ac heads. On your anatol you probably just adjusted the dial at the end to a speed you liked right? Problem is sometimes that "value" if you will wouldn't always be the same speed, say you were printing all heads and the press was really sucking air. The ac heads print at what you set them at, period. They are also much faster. If you are doing 1 or two color basic spot color stuff and are not going to try to run your press at top speed all the time, the ac heads are probably not necessary, nice, but not necessary. If you want more exact control(alan's RPM is still my favorite press for complete exact control) the ac heads are the way to go.
I think you guys have a valid point with priority on a press being ac heads over ac index, but I think Zoo probably hit one of the maid reasons on the head-
I think you see it the other way around b/c you can streamline mfg of a machine if all the units have the same servo driven base. Pneumatic index can be annoying but it does work fine and, if you take the time to really dial it in for the exact platens you are using can be very fast. Downside of air index is that if you don't keep it dialed you'll prematurely wear the bearings and forks and need a re-registration sooner than you should.
If you are going to break out the money for reliable and exact ac heads, chances are you are going to want a indexer just as reliable and exact. When those print heads start flying, why would you want the indexing function be the thing that slows you down. Think of it as the weakest link in a chain analogy. I am pretty sure if you order a press new, you can specify a pneumatic indexer. But how much exactly do you save? $1000 maybe(I could be way off)? If you are going to buy a $40K or more press, the $1K or whatever to me seems like small potatoes especially for such a intricate part of the press as a whole.
I'll probably catch heat for it but, if you are looking at a intermediate level press(just assuming you were if you want ac heads) you really owe it to yourself to check out a S.Roque YOU or ECO. Both are all ac machines.
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I am also a fan of the rpm head controls. That seems so nice to be able to adjust on the fly and record what that job printed at. Is there a patent that, that is preventing other manufacturers from adopting that control?
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Thanks for the replies, and keep them coming if you have more to add.
I am searching both the used and new market. If I go new, I'm pretty sure I want to go AC and servo. The ones that stand out to check out are The Horizon XL, Stratus, RPM, S Roque, and of course Diamondback XL and Sporstman. The only presses I have not actual seen on that list is the Stratus and RPM. I didn't include MHM on the list because I'm pretty sure that is going to be out of my price range. I still have a lot of calls and research to do. I'm not looking to buy tomorrow, just trying to get my ducks in a row.
It seems a lot of good deals come up on the used market for the all pneumatic presses.
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I wouldn't exclude MHM, it is probably very close to the RPM and Sroque machines pricewise although that Diamondback XL is an excellent value for what you get.
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Not sure when they are doing it, but MHM was supposed to drop the E-Type. Then their S-Type was supposed to be their entry level press.... That is an expensive entry level press....
Out of the three(MHM, S.Roque, RPM) The RPM and the S.Roque YOU are roughly half(maybe closer to 45ish %) the price of the S-Type. You get the digital controls and readouts(which I absolutely LOVE) with the RPM, but you get more press and capabilities with the S.Roque.
When we got our last press(about a year ago) S.Roque, RPM and MHM were our finalists as well.
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Another benefit of servo not mentioned is you have full control at a touch of how it acts. You can reverse direction if needed, you can half index for easier screen access. and you can control its index speed any way you need.
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Only thing I know about servo is they run smooth and quiet, and I really can dig having AC print heads, an all air machine gets the job done but it sounds like your working in a machine shop LOL.
Darryl
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I got to see the Sroque this weekend and I liked what I saw. I need to do a review of the ISS Ft. Worth show sometime soon before I forget what I saw. If/when we get a new press I don't know that I'll be able to choose a press that doesn't have as much precise control over the print settings as our RPM. Flood & squeegee speed, pressure, print length, off contact, squeegee angle, flash time, bulb intensity, standby intensity, standby time, plus a few others I forgot have exact numbers that represent a very precise measurement that is duplicated exactly from one print head to the next. Now if this press had knobs and toggles for everything it would still do all it can do now but it has been fantastic to be able to set a job up precisely like it was the last time we printed it. It's also nice when you get to know the press well to be able to set up a job quickly because you know roughly what settings will work since you've done it so many times and each print head is the same and can be set exactly like the others and you know there is no difference. The AC print heads with the encoder system allows so much of the digital readouts to be so accurate and repeatable from one head to the next. The air rhinos have decent digital control but it's nothing like the AC machines.
I love the CH3 and the MHM machines, now the Sroque is in that group after spending some time around it. I know that the machines that get me excited aren't exactly the ones that most shops can afford so that's why the entry level press market is so competitive. Stepping up to AC print heads means you have fewer options for entry level machines but at least there are a few options available where 10 years ago there was almost nothing.
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What would you all choose? Two more colors, or servo/ac (6/8 with servo and ac or 8/10 pneumatic)?
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Trick question! :P
Save up if you can for the 8 color servo/ac.
You'll have more money by then and will
be glad you did.
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Agreed with Gary. If you can afford that 8 color pneumatic, do yourself a favor and just get the 8 color servo so you aren't buying the servo 2 years later either kicking yourself or trying to find ways to lower your revenue because you're printing too much and not quickly enough or because you are in too high of a tax bracket... not that anyone does that who frequents here... but I hear it's done from time to time... :P
However, if absolutely unable to, I would go with 2 more heads provided you are getting a good chopper pneumatic press. We've used both the V-squeegee and a chopper carriage on an all-pneumatic and currently have a 12/14 ac-servo. I'd say there is a huge difference between the pneumatic v and pneumatic chopper, at least in our experience (though the pneumatic chopper press was a rhino, which was a really nice pneumatic press -- but I imagine they may all be just as good these days???). The major benefit of the ac heads that I've seen, as I believe has been mentioned already, is that while you can print with comparable quality (on typical prints), you can do it faster on the ac/servo presses, so you have more throughput capability per day when your business grows. So for example, on the Rhino, we were probably printing around 7"-12" per second print speeds plus had a slower index. Now we're doing 10"-25" per second print speeds (provided the ink cooperates, and most do [though not all]) and have a faster index with the servo index. Maybe other variables changed that have created the big speed difference other than the print head speed and indexer, but printing with speeds twice as fast than the pneumatic on a multi-thousand piece order adds up fast. So, I don't think the quality has improved, but we're getting jobs done faster, and thus you will be getting paid more per hour should your prices remain the same, which only means more time to pursue other jobs...and so goes the endless cycle.
Ok, I've stated nothing not already said.... but like Gary said you should just go servo 8 colors if you have the space to do an 8 color pneumatic press and consider it an expense to do business. I haven't looked in a couple of years, but what can the difference in a monthly note really be between an 8 color pneumatic and an 8 color servo? Not sure....
My $.02.
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I am going to "third" the opinion to hold out for ac heads on the 8/10. If you are going to be running bigger more complex jobs with more colors you will want the ac heads....
You could always order a 8/10 with 6 ac heads and 2 pneumatic, say maybe on head 2 and 6 or something.... But I would still say go with the ac heads.
I know I am not exactly in your backyard, but you are welcome to stop out here and check out the difference in the two types.
You WILL NOT regret holding out for ac heads.
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I am going to be a loner here and vote for more heads on the air machine. I have a 10 color gauntlet Deuce and I friggen love it....we also have a 6 color early generation gauntlet and there is a major difference between the two. So I would drop a vote for a current (atleast year 2000 on up) all air machine and hell, you can do just the same with that as ac... not as fast, quite, nice but it'll do what you want it to...ac is the bees knees but man, it is NOT necessary to have a great press....but this is my humble opinion ;D
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I haven't looked in a couple of years, but what can the difference in a monthly note really be between an 8 color pneumatic and an 8 color servo? Not sure....
On a new press, I'm pretty sure I'd be going servo/ac. The increase in price seems like it would be worth it (although I have no actual experience with it).
Pneumatic vs servo/ac is more going to come down to used vs new. There seems to be some real good deals out there. So I was actually comparing and contrasting the idea of buying a used 8/10 pneumatic for a fraction of the cost of a new 6/8 servo/ac. If I did go that route it would definitely be a chopper, not a v, and be a somewhat newer press (less than 10 years old).
But I'm still in the early stages and have a lot more info to gather.
TCT, what state are you in?
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I agree with Homer you don't have to drive a Bentley just to go to the store when a Kia will work LOL, but being able to have the nicer stuff is good..
Darryl
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I am going to be a loner here and vote for more heads on the air machine. I have a 10 color gauntlet Deuce and I friggen love it....we also have a 6 color early generation gauntlet and there is a major difference between the two. So I would drop a vote for a current (atleast year 2000 on up) all air machine and hell, you can do just the same with that as ac... not as fast, quite, nice but it'll do what you want it to...ac is the bees knees but man, it is NOT necessary to have a great press....but this is my humble opinion ;D
Nope, you're not a loner -- I agree with you if the choice has to be between two more air heads or 2 less ac heads. At the end of the day, it all comes down to speed being the plus of the ac/servo, in my estimation. If you the pneumatic will pump out what you need currently and you can find a steal of a deal on a pneumatic then go for it and upgrade in a few years when you have to have more throughput since you won't be so heavily invested in the pneumatic.
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I think if you go air, do yourself a favor and trade all your mesh in for S thread or equivalent. S thread almost negates the advantages of AC heads if you were using standard thread mesh counts on the AC driven press, in my opinion of course. I just know the advantages and differences in speed we see going from standard mesh to S thread is huge on an AC head so I'm assuming you'll see similar gains on an air driven carriage, but I've been wrong before.
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I'm up in MN, aren't you out east?
I guess another question would be, are you thinking pneumatic index? I don't know off the top of my head, but a all air 8/10 would probably draw quite a bit of air..... I know our 6/8 all air draws more than our 10/12 ac.
Guess a good question that hasn't been asked is do you have steady work to keep a larger press running? Chances are if you have the business to support it now, in a year you will be busier and wish you went all out.
When we got our first auto it was small and cheep. We couldn't fit a large press it even a 8 color in our first place. We literally had to take the front store front windows out to get the press and dryer in. Anyway we went small and cheep, no bells and minimal whistle. After printing on that over the years, I said to myself next press is going to have EVERYTHING, I want top notch! That is what we did and my only regret is that I didn't do it sooner.
If it comes down to a used machine, and you 2 station it ac heads, if you have the room I would say 2 more stations.
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Whe we first went to A/C, one reason was we would have had to buy another compressor if it would have been an air machine. The price of A/C versus another compressor was so close it was an easy decision. No regrets
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AC/servo all the way.
Better control, more consistency, easier to dial in, and FASTER when it counts.
If you need to upgrade later, better re-sale value if you want more heads.
I've used all air machines, air/servo machines and I currently run a AC/servo Sportsman. It rules.
IMHO, only pneumatic thing you should ever worry about is does the press have air clamps for the squeegees.
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I think if you go air, do yourself a favor and trade all your mesh in for S thread or equivalent. S thread almost negates the advantages of AC heads if you were using standard thread mesh counts on the AC driven press, in my opinion of course. I just know the advantages and differences in speed we see going from standard mesh to S thread is huge on an AC head so I'm assuming you'll see similar gains on an air driven carriage, but I've been wrong before.
Alan, correct me if I`m mistaken but didn`t you used to use as well Newman Roller Mesh. Just asking as most of our frames are stretched with Newman Mesh but we have changed now a few to Murakami and NBC S-mesh. For us with our Diamondback it`s much easier to print using the S-mesh so I might start changing more screens to s-mesh.
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I think if you go air, do yourself a favor and trade all your mesh in for S thread or equivalent. S thread almost negates the advantages of AC heads if you were using standard thread mesh counts on the AC driven press, in my opinion of course. I just know the advantages and differences in speed we see going from standard mesh to S thread is huge on an AC head so I'm assuming you'll see similar gains on an air driven carriage, but I've been wrong before.
Alan, correct me if I`m mistaken but didn`t you used to use as well Newman Roller Mesh. Just asking as most of our frames are stretched with Newman Mesh but we have changed now a few to Murakami and NBC S-mesh. For us with our Diamondback it`s much easier to print using the S-mesh so I might start changing more screens to s-mesh.
I had 20 rollers with 205N in them but now I'm down to about 12, and then I had 5 102N's and they all exploded when I tried to retention them for the first time. They wouldn't even get within 5 newtons of their maximum after 2 runs through production and they all popped within 30 minutes of retentioning. I bought the panels and they were white mesh, which at the time white roller mesh in that count "didn't exist" from what I was told so I'm still not sure what I got. It looked like roller mesh, but didn't hold up like roller mesh.
I stretched them up in april 2011 and don't get me wrong, it's good mesh, but it's not great. From what I know of the higher counts, the 272 in particular is it's great, Danny G runs the heck out of it at his shop so that tells me it's good, and there are several award winning prints that have gone through 272 so I trust it, but I haven't had the best of luck with the lower mesh counts. The spec sheet for the roller mesh doesn't exactly match up with what you see under the loupe so I just don't like the fact that you don't REALLY know what you've got until put ink through it and do some measurements. The specs on most all of the other mesh manufacturers I've used are way more accurate to what the mesh actually is so I can look at the spec sheets and get a good idea of what's going to happen when I use that mesh, not so with the roller mesh. The thread thickness and open area that the mesh is supposed to have doesn't jive with what the spec sheet says but that's not a deal breaker for most shops and I understand that. I'm just too picky I guess.