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screen printing => Screen Making => Topic started by: ZooCity on August 17, 2011, 01:03:30 PM
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Homer's post got me all hot and bothered about making a pre-reg system again. I figured I'd start a fresh thread so as not to steal his thunder on his post. I know Alan and others are working on this sort of thing too and we're probably all too busy right now to actually build the damn things so let's hear everyone's best ideas and viciously criticize and tear them apart until we find a really solid one or some good elements at least. How's that sound?
Here's my running concept, I think this may have been loosely mentioned before somewhere. It's basically combining the Pin-Lock and Tri-Lock system and eliminating reg-marks all together as well as nixing a bunch of taping:
We have screens from 25"x30" up to really damn big so I'm putting a big 'ol vac frame in at our new space. This means no crap on the glass for any pre-reg. The textile and flatstock screens need to share the expo unit. We do have a smaller unit that I built that could have permanent bump stops or whatever but that's more floor space eaten up.
Use a hole punch from one of our sister trades, maybe like this:
http://www.takachpress.com/servlet/the-291/Punch-Registration-System-6-dsh-Hole/Detail (http://www.takachpress.com/servlet/the-291/Punch-Registration-System-6-dsh-Hole/Detail)
{Or maybe cheaper. Maybe you're a total cheap-ass and use a three hole punch from the office supply store. And buy a second one to dismantle and use holes from.}
I'm not sure which would be superior but you could either use sheets only and punch those sheets ahead of time. Or you could print off a roll feed first and them stack the films together and punch them all at once. This is the critical point here- if the holes don't get punched accurately this whole concept won't work too well. I'm leaning toward sheets only and pre-punch but will r&d it both ways to see. Using roll would save film but I'm concerned it will curl to0 much to get an accurate punch after printing.
I have a template illy file that all art gets placed in before output. There's a set of guides you can turn on or off showing different platen print areas at true size as well as placements for left crest, etc. Well, you can see where this is going- Place the art before it goes to rip where you want it to land on-press for that particular platen, print on those punched sheets and now you have each color aligned as perfectly as an inkjet will allow onto films that are their own carrier sheets with no reg marks, with punch holes ready to go.
From here you could either:
- make a jig that's a reverse/flip of the thee point jig used on press allowing you to load the the screen in print side up for film placement, like the MHM system does. Except no alignment is needed here, simply fit the sheet on the reg pins, tape and carefully pull it off the pins and its off to expose a (presumably) perfectly registered screen with no bump stops, etc. needed on the glass
- Do something like Homer's setup and the tri-loc does and put the film on the pins on the expo glass where you have the bump stops
Downsides:
- Wastes film
- Takes the added step of punching the film.
- Might not actually work.
Upsides:
- No reg marks! If it works this would be huge. You're saving all that blocking out and eliminating the risk of any ink getting through the blockout.
- No lining up a film or screen by eye. Saving even more time and eliminates another step where there's room for error.
- Very little or no tape needed. You still need to tape in scenario 1 above but not at all in scenario 2.
- No carrier sheets, the films are the carriers.
- Allows you to expose screens as fast as the unit will allow.
I'm pretty sold on it, in my head at least. And if it doesn't perfectly reg screens that's fine by me. It's still saving a crap-ton of time. But, I bet it can reg things pretty close.
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I've used the high placed 3-wide-1 way-low reg marks for the last 10 yrs, the idea is to get the regies out of the squeegee drop area, this way, even if you 'forget' to tape or blockout the back of the screen, a reg mark will never print on the shirt. Just as jay has done with the reg marks on the glass, you can't miss the mark as long as it's lined up... that's it. Line it up right, dial in your reg frame and you'll never touch a micro again.
You use a few more inches of film in the process but who cares, the time saved in set up pays for any extra film you may have used. The mind set knowing that a reg mark will never again 'accidentally' print on a shirt and any new guy who runs your press can set it just as easy and quick as the last. This is golden if you do discharge.. you can't blow out a discharge reg mark on 45 shirts.
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I love that idea John placing the reggies off the print area. If your reg system is tight even a tiny tweak can be done looking at the art instead of the reg marks.
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whats wrong with carrier sheets? on my manuel i use vastex vrs system and freaking love it.
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It's and added and unnecessary product. M&R should have been able to design a product that doesn't need carrier sheets. Homer's system once perfected, should be faster and cheaper than the tri-lock.
I would have personally put pre-reg on a light table off the expo unit to save some time, but that's me.
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whats wrong with carrier sheets? on my manuel i use vastex vrs system and freaking love it.
It's an added step and a step that something can go wrong as you have to tape the positive to the carrier sheet.
With the inverted reg marks on the glass, the reg marks on your film line butt-to-butt with the ones on the glass.
Print film, place on glass (use tack cloth from paint dept in home depot/lowes on glass, removes lint and when you add pressure, will help the film stick to glass) burn and you're done.
No film to peel from the carrier later.. the carriers also have a life before the pre-punched holes start to loosen and you need to buy more carriers. I love the tr-loc but the initial high cost and then it uses consumables turns many ppl off. It is however the best option for a full blown factory who can absorb those costs a little easier than you or i.
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I love this subject. I am going to go out and take some pics of what I have currently and what I'm thinking of doing. My artist and I have thought about doing the hole punch idea. Your thinking of lining up the job on an FPU of sorts, then punching them out right? I just really wonder if there will be any sliding or moving of the film when the punch is penetrating all of the film, or if there is a way to do it separate and still not lose registration. I like the hole punch but I'm not ready to go down that road yet and I have some other areas I'd like to explore before getting to it because I think there are better/easier ways.
Right now, I really like the system John52 has in his shop. I am going to go out and take a pic of what my FPU looks like, and then a pic of what I want it to look like in the MHM FPU. But the only downside to the MHM FPU is I'm not using an MHM machine and the pallet jig on press will not be exactly like the FPU.
I really want to get my aluminum piece cut or someone to let me buy their Tri-loc pallet jig. Then I'd have one of the best DIY regi systems around. Ok, I'm going to take some pics.
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I think the hardest part of the whole system is replicating the film positioning part on press.
MHM's do this with pins on the screen that lock into the same place on every head. If I didn't
have an MHM I'd be looking for a way to replicate that. Seems much easier than the pallet jig
setup. Just my $0.02.
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eb, you are totally right. MHM's system makes WAY more sense. Take a look at offset presses, the plates lock into the same position, registration is done OFF the press.
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I have also looked at retrofitting bump stops on each printhead. It's the closest thing we non mhm users could do to replicate that system. I don't necessarily like putting the pallet jig on and off when needed but it's really not an ass whip like you'd think. Especially when considering the time savings you get by using a reg system. Uploading pics to photobucket now and will post them after we run a quick job.
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What about using the frame air locks or something like that and modifying your screens? Are they
stable enough?
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You could put grommets on the screens that line up with the locks. I've tried to think of a way to do this and make it work. I am just not sure if side to side torquing would mess those locks up. Since they can slide on the screens now, there isn't much risk of that.
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I haven't read all the posts yet -but Zoo -the problem you will run into is the printer itself printing the films in registration. I know my 1400 does not put the design in the same exact spot on every piece of film -it's close but not close enough. Maybe your printer will? have you tried it yet?
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I have also thought about drilling a 1/8" hole in two left side corners of my frames, put a metal insert in there and glue it shut . It's not a pin, but an opening for a pin that could be attached to the platen or not necessarily on the platen, but somewhere else on the press that is stationary.
with all the time thinking about this damn system, we all could have bought a tri loc haha
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I don't think there is a printer on the market that can put it in the same spot. They are not designed to. They get close, close enough for trimming and binding and such, but the takeup system is so different than an offset press where you might be running that 1 sheet through 3 more times.
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Alan, I'm suggesting either pre-punch sheets or print from roll and then punch the sheets, either stacked or one at a time, whichever works best. The goal here is no reg marks, no aligning of positives using reg marks. None of that. Just print - punch - align to tabs and go.
These hole punches are designed to let other types of printers perfectly align their substrates on the table. We should be able to put the film in the punch and square it up accurately. Assuming the sheet sizes are consistently cut or, if roll, the printer cut the roll at the same place it should be very close as far as the punching part goes. An easy check would be to always print a little 0.5 pt dash at the top to make sure the roll film is starting at the same place each time and use a cutter to trim the top off if needed.
Homer, this is all speculation, I haven't tried it out yet but will soon.
Now regarding the printer itself, I think roll feed would be fairly accurate seeing as the roll on the 4800 isn't like a toilet paper holder, it actually indexes the film forward at a certain rate. There is variance on longer prints on inkjets but here's my take: you have to deal with that whether aligning the positives by eye or with punch holes. The real challenge is getting the media to feed very accurately.
All that said, even if it's a little off by the time it all gets on press, I'd be a happy camper with all that time saved. Think about it- even if it's not perfect, you run your base print or a key color, check each screen visually before printing, maybe tweak a micro or two, test print, maybe tweak again, maybe not and run. The only movement happening on press would be from the micros and if you think that takes too long, think of all the time saved in pre-press with this method. It's literally film output to on-press with no visual alignment whatsoever up to that point.
Perhaps one of our resident inkjet gurus could chime in on the concept?
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Ok, I got some pics here. I'll start with what we are doing now, then what I want to do in the future.
(http://i485.photobucket.com/albums/rr211/alan802/SRI%20Pics/1000001381.jpg)
(http://i485.photobucket.com/albums/rr211/alan802/SRI%20Pics/1000001376.jpg)
(http://i485.photobucket.com/albums/rr211/alan802/SRI%20Pics/1000001377.jpg)
(http://i485.photobucket.com/albums/rr211/alan802/SRI%20Pics/1000001383.jpg)
(http://i485.photobucket.com/albums/rr211/alan802/SRI%20Pics/1000001382.jpg)
(http://i485.photobucket.com/albums/rr211/alan802/SRI%20Pics/1000001391.jpg)
(http://i485.photobucket.com/albums/rr211/alan802/SRI%20Pics/1000001392.jpg)
(http://i485.photobucket.com/albums/rr211/alan802/SRI%20Pics/1000001394.jpg)
One of the main things I want to change with the next version is where the "bump stops/post" come into contact with the frames. I don't like my posts and I don't like that they bump up against the rollers and want to move them to the newman and shurloc frame corners. I think I'll get better results by doing that. I also will move to square bump stops as seen on the next set of pics.
This is one option I have for an FPU. Notice I have the square tube aluminum bump stops located in a place where the frame corners will touch them.
(http://i485.photobucket.com/albums/rr211/alan802/SRI%20Pics/1000001371.jpg)
(http://i485.photobucket.com/albums/rr211/alan802/SRI%20Pics/1000001372.jpg)
(http://i485.photobucket.com/albums/rr211/alan802/SRI%20Pics/1000001374.jpg)
Now I have the MHM style option that I am seriously considering. Disregard the almost nonexistent grid I have on the next set of pics. I just drew them for the sake of taking these pics but I'll make something much more professional looking with a nice grid on a white mdf board or something similar. I'm going to build it up so when I lay the screen down it will come into contact with FPU while the corners will bump up against the square stops.
(http://i485.photobucket.com/albums/rr211/alan802/SRI%20Pics/1000001384.jpg)
(http://i485.photobucket.com/albums/rr211/alan802/SRI%20Pics/1000001385.jpg)
(http://i485.photobucket.com/albums/rr211/alan802/SRI%20Pics/1000001386.jpg)
(http://i485.photobucket.com/albums/rr211/alan802/SRI%20Pics/1000001388.jpg)
Those are just a few pics with some random ideas. I think I might run into a problem when using the MHM style FPU and trying to fabricate a pallet jig since the frame will be one side up on the FPU and then flipped upside down when putting the screen on the press. I will make the bump stops tall enough but I'm still uncertain whether they will touch the frame corners in the exact same place because these frames aren't perfect. I can see there being some angle on the corners and there being a difference in location where the corners touch the stops from pallet jig to FPU. I could be wrong and there is only one way to really find out, trial and error.
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Nice pics Alan. The MHM style thing you have is what I'm leaning toward. I feel like anyone good with fabrication skill could whip this up for not too much cash. If you were to use punched sheets all you would do is line 'em up at the top to a set of pins, smooth down the film, tape the film on and gently remove the screen/film to go to exposure. You could take second to inspect both the screen and the film at once. You could also stack all the films up, going one at a time for visual inspection to check for art or reg errors before putting each one on their separate screens at a station like this. If one film is a little out you manually align, forgoing the pins or mark that screen so you'll know it will need tweaked on press.
You said:
I will make the bump stops tall enough but I'm still uncertain whether they will touch the frame corners in the exact same place because these frames aren't perfect
And I came to the conclusion after looking hard at the newman pin-loc system that both screens and presses have more variance than the film alignment system does. Just embrace the variance and don't worry about having absolutely perfect pre-reg is my take on this. Why fight to have supremely accurate film alignment when the screens will throw it off and so will the press variables? Just keep it quick and clean and then adjusting micros now and then won't be such a huge deal.
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It's literally film output to on-press with no visual alignment whatsoever up to that point.
Perhaps one of our resident inkjet gurus could chime in on the concept?
This was and still is the best part about imagesetters, they came with a cutter and punch option.
It'll be a glorious day when this technology is realized by Epson or some other Joe who makes and "add-on" so when the film feeds out of the printer, it feeds through the punch and does the magic.. all from your 17" ink jet.. there's a pre-reg system waiting to be exploited.
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It's very much awesome to see people really discussing such beneficial and educational subjects. The pictures are an addded bonus. Thanks for the extra effort you guys. I think I'm gonna cry. Sniff. Sniff. :'(
Good stuff.
Ok, carry on.
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Well epson has the cutter already. ::)
Thing is, the cutter should be as accurate as the part that indexes the film forward. At least that's what my theory is banking on.
So, if you're accurate enough in squaring up the top of the film to the punch it should be kool and the gang. The bastards do tend to just feed film for no god damn reason on a regular basis so you'd have to watch out for that. Having that little indicator line print out on your films would notify you when that happens.
So imagesetters had all this jazz included? Do they still? Kind of makes that massive up-front costs look more justifiable and sounds like a good time to me.
I was watching that newman pin-lock video again and there is so many steps on these systems. I know the goal is to absolutely minimize change-over and downtime on autos. It just seems like a lot of alignment and taping to me. There's room for error in initial placement on the carrier as well. With the system I'm describing, whomever placed the file onto the output template makes that decision and sets it in stone.
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Zoo - I agree 100%. I watched every damn video over and over again too, it seems like way too much tape and room for error. I'm not saying my system is great, perfect or anything spectacular -but the one you are going at sounds pretty damn sweet. not much room for human error -that I like. And I would pay a decent amount of coin for a system like that. Plus, the newman system requires me to use nothing but rollers and I have to alter my screens. There needs to be something that works on any type and size of screen, out of the box, no alterations needed, print films and go. . .and a reasonable price.
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Alan, thanks for the pics, that gave me an idea. Will get back to you guys with the pics when it is done. It should be the simplest one to use (at least for manuals with the rear clamps).
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Just picked up a pin-lock system as chance would have it. I'm going to run the system the "traditional" way once we get it setup and then, once I know the parameters of the pin system, I'll use it as a control to test out the punched films theory. I know the pin lock is likely as accurate as it gets, next to mhm's pin system so it should be a good starting point and eliminate any chance that a jerry-rigged 3 point reg is the issue.
Spoke w. George from Stretch about this and had a great talk. I also invited him over to the boards. Newman did sell their punch for awhile but not too many shops wanted it or were willing to pay for such a system. It looks like the film reg pins are fairly standard, oblong shape and/or I may be able to swap out for my choice of reg pins. There's still plenty of industries and arts using this method so the gear is out there. Theirs used a vac table (like a graphics or transfer press) to hold down each film sheet so it was not only square to the punch but perfectly flat- this should eliminate all but the printer itself and the squareness of the film as major variables.
I'm going to homebrew a vac table/punch setup sometime before the year is out hopefully and give this a whirl. I have high hopes for this but if it doesn't work we can still use the system the regular way and it'll still work out just fine for single color prints either way!
This thread has been a good kick in the pants. Thank Homer for sparking up this topic with your glass-reg masterpiece.
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Plus, the newman system requires me to use nothing but rollers and I have to alter my screens. There needs to be something that works on any type and size of screen, out of the box, no alterations needed, print films and go. . .and a reasonable price.
Oh, and I agree, this is a weakness. Then again, 3 point has it's weaknesses too seeing as all the frames are bit different. The pin lock is easy going in that all you have to do is remove two end bolts on the short roller and put 'em on. But, if there was a way to get universal pins on all screens it would be optimal. I know you can do this easily if everything in your shop was mhm but I somehow don't see three new mhm presses in my future. It can be done though- your own type of pins and a jig and there you go. Bet you could even bolt the newman pins onto statics somehow. I think Roger Jennings had something going like this at one point.
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Here is what I plan on doing with my aluminum slab then I'm going to affix the pallet extrusion that is on the current pallet jig. I plan on putting the stop blocks on the pallet jig to duplicate the FPU. But I think I'm going to make a change to the stop blocks and keep the one that is on the long side of the frame the same and turn the 2 blocks that are close to one another into one 90 degree L shape block. I don't really have a reason for doing so other than I think it will be easier to do that rather than get the 2 blocks perfectly placed to form a 90 degree angle. I think getting those 2 units to be exactly the same is the key and if one is just slightly different than 90 degrees, I will get bad results.
(http://i485.photobucket.com/albums/rr211/alan802/PalletJigplan.jpg)
(http://i485.photobucket.com/albums/rr211/alan802/pallet-jig-plan20.jpg)
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Al -you can't cut that aluminum yourself? might take a while but the right blade and a jig saw will do it.
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Aluminum is easy to cut w. a carbide blade. Just remember to reverse it on a table saw. I almost impaled myself with a 2"x16" shard of aluminum trimming down a platen once.
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Al -you can't cut that aluminum yourself? might take a while but the right blade and a jig saw will do it.
Drop it at the local waterjet shop, give him some freebie shirts with his logo (if you have a DTG) for the business call then go back, print and make money. Pick it up a few days later and all the cuts are perfect, edges are smoothed and all the tap holes to mount the stop blocks are ready for tapping.
F that jigsaw and table saw.. I've cut enough 6061 to know it's gonna take me 2 hours to measure and make all those cuts, then sand the edges and drill and tap holes.. yeah no thanks. send it out.
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Hey Alan, good stuff dude, have you thought about backlighting the art board?
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Hey Alan, good stuff dude, have you thought about backlighting the art board?
Yeah, I've got an old light table that needs a new top that will be a perfect fit with the FPU.