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Is it Time for an Automatic? - SPSI Inc.

Is it Time for an Automatic?

Buying a new press is a huge investment and for some, it's just adding capacity to an existing print shop, where for others it’s a leap of faith into the unknown, often with finances promised but not guaranteed.

Once the decision has been taken, all that remains is the big question “Which Press?”

There are lots of considerations to take into account here, Brand, Price, Configuration and type.

MHM S-Type Xtreme Automatic MHM

Screen print presses come in all types of shapes and sizes, I have run presses that are all electric, all pneumatic and even all hydraulic, the options are endless.

All machines print t-shirts. They all hold a rubber blade against a stencil and push ink through holes while laying down colors in succession.

If we took one printed t shirt of the same design, from every press that ever existed, ranging from the very basic early ones to the latest all singing and all dancing press that can set itself up, and we lined them up on a catchers table at the end of the dryer, I would challenge any printer in the industry, myself included to tell me which shirt was produced on which machine.

My first experience of printing was on a four color automatic press that was possessed by an evil spirit with a deep hatred of all living things, we used it to print three color Yankees panels on bogey green fleece that halved its mass once the panel was removed from the glue. The press was an oval configuration that required the operator to walk into the moving pallets and load, the trick was to get out of the machine before it whipped round the corner at light speed and inflicted the worst case of squeegee rash upon an innocent loader, in the interests of safety a pressure pad was located just before the point where the last pallet was accelerated into hyperdrive around the corner of the machine. This pressure pad would allegedly stop the machine and save the loader. As I mentioned, this particular press was possessed and was in the throes of repaying a debt for a crime performed in a past life., therefore the pressure pad would perform many functions including starting the machine, making it perform a double index (the manufacturer said this was impossible) activating the squeegees, almost all functions except stop. The machine would start without warning and all the loaders would receive a “love bruise” just at the base of the spine whenever they had the misfortune to turn in late and were assigned to the beast in the corner.

Although this machine had several severe personality disorders it still printed garments! Yes it was difficult to use, yes it inflicted pain and yes it really did need a priest, but it knocked out Yankees panels in plastisol puff at the rate of 3000 per day and no one could tell they were produced on a machine that was two doors down from the gates of Hell.

Screen print automatics have two basic configurations, the oval and the carousel “round” option. Asking which is best, is like asking which flavor of crisps is best. You may think its ready salted but trust me there is someone out there who still craves hedgehog flavor!

Oval presses have many open areas to insert special flash units, flocking units, chilling units or even just a small boy with a sticky piece of tape to remove lint. They are most commonly used to produce large flat panels and can be configured with up to 60 stations.

MHM IQ Oval Compact MHM

They tend to be slower than circular machines and therefore lend themselves to fashion work. The early configurations would have the printing attachments, squeegee arms, flash units etc on one side of the press and leave the opposite side of the oval open to allow more than one loader access to the machine safely. When I first started printing, a team would consist of two loaders, a puller and a catcher, with the “printer” constantly walking round the machine, monitoring the inks, maintaining quality and expertly rolling a rollup while the machine lifted and lowered while pushing out the required 300 pcs per hour.

The drive systems on oval machines can vary, there was an old Precision machine that was hydraulic and used a chain to drive the pallets around, this method can still be found on machines produced today. The main issue with chain driven machines is that very much like a chain on a bike, the chain stretches over time and needs to be re-tensioned. To tighten a bike chain is relatively simple, but when we rely on the chain for the position of the pallets which dictates the registration between colors, we can hit problems it can be much more technically demanding.

Chain driven gave way to solid driven and this eliminated the issues of stretch, but the engineering must be much more robust and dependable to cope with the demands of a large press running day and night.

Independently driven pallets are a new system of tiny little robots embedded in the pallet arms, these are typically found on the largest oval machines and eliminate the need for connected drive systems, therefore eliminating the issues of stretch or brake slide, they are the most accurate method of driving pallets along a large oval area but they rely on a copper communication strip which must be kept clean, a screen print shop is not the easiest environment to keep clean.

Carousel or round shaped machines are now the most popular format found in almost every shop across the globe. They are circular with a central drive system and usually have two open stations shaped like a piece of pie which allow for one loader and one puller. One of the earliest circular machines I worked on, was driven by an air cylinder which was controlled by a shock absorber similar to those found on a motor car. The resulting machine would clank and bang so loudly we had to turn up the radio to hear Radio 1s “Our Tune”. This machine was so animated in its operation that it needed to be bolted to the floor to stop it slowly walking across the factory floor! (unless it was also possessed and wanted to escape the daily dose of Simon Bates that could reliably be found in a 1990’s print shop)

These round shaped machines are fast! They can produce up to 1400 pcs per hour, much more than a regular human can consistently produce. I can load shirts at 1400 per hour! But only for ten minutes at a time and I would not guarantee there would not be a under the armpit print where there should be a left chest print!

The most popular configuration is probably 10/12 this means 10 printing heads and 12 pallets, but my advice is always to look back at past history if you have it and ask the basic questions of how many colours on average did you print last year? What was the average run size? Using this information, we can try to predict what configuration of new press to purchase. Include any special effects like foiling and remember that a flash unit takes up a print station.

New machines or even well maintained used machines can provide a superb revenue stream while they are running, however as we only earn money while the squeegees are moving, we must consider the ease in which we can set up these investments from one job to the next. When looking for a new investment I would always advise to look at the speed of job change as well as the top speed per hour, it is no good having a car that goes 200 mph if it takes you an hour to open the door and start the engine. The use of registration aids and tool free setup can allow an intelligent quicker return of investment than a fast machine that requires an engineering degree to setup and change- over jobs.

The brand of machine you choose is a tricky one, I have my favorite and its difficult to stay impartial when writing about machinery, but I would always recommend to look at the setup times and also the level of service available, if it breaks ( and it will) can you fix it yourself? Does it need a computer genius? Can you get a technician at 8pm at night on a Friday when the job on press just simply has to go out no matter what?

Whether you pick a blue, green, or even a pink one, I only hope that the press you buy is not possessed by dark spirits from the underworld and it brings joy and wealth to your door.

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Article written by Tony Palmer, Palmprint
Tony has more than 30 years experience in garment decoration ranging from manual screen printing on hand carousels to the operation of multi-color automatic presses.  Specifically Tony is an expert on MHM Automatics, Tesoma, Exile Spyder, Douthitt CTS, Zentner, and numerous manufacturers of textile decorating equipment. 

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