multiple topics - quality improvement
I have a few questions about printing with my C&P 10x15 NS that I thought I’d ask of the experts here at briarpress.
Instead of posting several topics, I thought I’d post one and hope for the best. Any assistance with any of these would be greatly appreciated. It’s a novel so my apologies in advance.
Registration.
I have the recommended aluminum base from boxcarpress that is too large for most projects. Obviously, I can’t use gauge pins in the area of the base. I’d be very interested in learning what others are using for alternate pins when the base is too large for the piece. I am considering cutting the base down but haven’t done so yet.
Inconsistent Coverage.
With recent projects, everything has been printing as expected then, all of the sudden, I’ll get many prints where it appears that the rollers are not inking the entire face of the plate (KF152 plates). My rollers are about a year old (from NA Graphics) and are very well cared for (cleaned and stored inside and in garage when temps are stable). The light areas continue horizontally across the image and appear to be random. In analyzing the ink on the plate, it appears that the rollers are not in complete contact with the plate. Any thoughts on what may be causing this? Please see next thoughts on rail tape. Also, is there a way to check the roundness/trueness of the rollers? I consistently use a roller height gauge from boxcarpress. I need to revisit their site to relearn what the appropriate ink strip width should be on the gauge. I have a general idea but would like to know for sure.
Rail Tape.
Relating to the topic above, I’m curious what others are using for rail tape? Are others using alternative tapes for the rails? I have rail tape from NA Graphics but I have to build up the rails w/ approximately 6-8 strips of tape so it seems more cost effective to use another tape for this instead of that many layers of expensive rail tape. Currently, I’m using blue masking tape from Home Depot but am concerned that may be variance with this. I have printed for a year or so those with this approach and have had great results until very recently.
Rollers.
Am I okay to leave the rollers on the press for an extended period of time if they are not in contact with the ink disk or plate? I sometimes take them off of the press and store them but other times leave them on the press without the chase/base in the position over the bed where the surface of the rollers is not in contact with anything. With that, what is the advantage of storing the rollers vertically?
Amount of ink versus roller height.
I’m struggling with knowing what is the best way to determine if inability to get a clean crisp print is the result of too much ink or the rollers being too low. As I gain experience, I feel more confident with this and can always observe the inking on the plate and results from the roller height gauge. Just wonder if there are any tips I should follow.
Makeready.
Can someone recommend the best resource for learning the ins and outs of proper makeready? I have used the instructions in “General Printing” (Unit 61, page 82) as I believe it is the most thorough explanation but I’m curious how others have learned (also using the APA makeready guidelines). I have struggled the most with feeling confident in my assessment of the print and building up successfully. It would be great to see a video of these processes. In thinking about this now, I recall seeing a boxcarpress video on the topic. Any other resources for building these skills?
Edge Painting.
I’m still searching for a reliable approach to inking the edges of paper (220# Lettra to start with). I understand that it is very much a trial and error learning process and have done some testing. I’m just looking for recommendations for what the best process is for clamping paper and what methods are used for applying the ink (brush, sponge, roller, etc.). Still researching, just thought I’d mention it.
Diecutting.
I have an upcoming job where I will need to punch a hole in the corner of 500 hangtags (maybe a .125” hole). Should this be done with a typical die cut or is there another approach to take (hole punch, etc)?
Thanks so much for any assistance that you can offer.
Joshua
Make your own register guides using the stock you are printing with, some brass or paper tongues, tape, and glue stick.
RegisterGuide.jpg
When a paper drill is not available you can use an electric drill. I’ve seen this method in old printing text books.
drill-paper.jpg
The uninked areas are from three possibilities:
-low spot on rollers
-high spot on trucks
-high spot on tracks
(low spot on plate we can ignore here)
The variable location suggests it is rollers or trucks. You need to determine that rollers and trucks are concentric. Roll each inked roller over a flat surface, check for light spots in contact. Then roll again checking for variations in truck contact. Or set the journals into v-blocks and turn rollers for a visual inspection of trueness.
How to get track/truck/roller into proper relationship has been argued repeatedly on Briarpress. You can search the archives.
Masking tape in many layers is not a very stable adjustment to the tracks. That’s why NA sells the nylon tape, which is dense, very durable and can be reused.
Morgan rubber trucks could solve many of your problems. Quiet and adjustable. Helps with rail vagaries and skidding. Easy to set exact roller, ink disk contact. You would be surprised how much quieter the press runs.
Megill’s Flexible Feed Gauges
These work very well, and don’t get crushed.
flexible.jpg
Morgan trucks may not be such a good idea with photopolymer plates; half the problems I had when first using photopolymer were due to Morgan trucks. They can be expanded eccentrically and develop low spots. Photopolymer needs much more exact roller settings than do metal forms, light but even. New nylon trucks would be a better idea.
Kort Adjustable Gauge Pins are a wonder to work with. These would get crushed by a base, though.
What size base are you using? Even with a 9x12 you should still have room to set these up on your draw sheet outside the base area. This might result in a bit more trim area on your sheet but to me that’s worth it for a quick and precise register.
Paul
The diagram showing a regular drill to be used on a stack of compressed paper is totally new to me. I would assume that the stack of paper would have to be extremely compressed so as to render it an almost solid mass. Regular paper drills have hollow bits that take up the material very cleanly. I am not at all sure how well a solid bit is going to leave a nice clean-edged hole through all of the sheets.
Has anyone actually done this before with satisfactory results? My guess is that a very sharp (new or like-new) bit would also be needed in this equation.
If this works, this is a brilliant solution for those who don’t have access to a paper drill.
Rick
Thanks for much for your helpful replies. Much appreciated.
Sharecropper, thanks for the direction and illustrations. The register guide idea is great and similar to what i have been doing. I have struggled with the paper strip as it seems to be less durable and strong for longer press runs. since my last post, I have switched to thin aluminum strips and that seems to really help.
I’ll definitely look into the Megill Flexible Feed Gauges. megahertz, thanks for the lead.
parallel_imp, thanks for the summary of uneven inking problems and solutions. I have since put put on nylon rail tape from NA Graphics that I already had but didn’t think I had enough to build up the rails. Currently, I have one strip of .01 on each rail, then two .005s. I needed additional clearance from there but another .005 was too much so I had to resort to the temporary solution of the blue masking tape which is thin enough. Is there a thinner nylon tape than .005” available for fine tuning?
I took the rollers off of the press to check that they and the trucks are concentric. I rolled each roller on paper to check for light spots but didn’t see any obvious issues. I also tried to check the truck roundness but am still having difficult determining if/where they (and the rollers) are out of round.
To troubleshoot, I alternated the position of the rollers on the press (3 rollers) and switched 2 from end to end. That made a significant difference and the press is inking consistently now. From that, I know that there is some kind of issue with the rollers, I’m just not clear which one yet. I’ll explore the archives for the best way to troubleshoot. I’m a bit surprised as the rollers aren’t that old and have been well cared for.
To revisit Foolproof546’s question, will a normal drill with a normal solid (not hollow) drill bit properly remove the paper from the stack? I’m also curious how you assure that the position of the drill is accurate through all sheets if you use a hand held drill. I will be drilling a hole in about 1/4” from the corner edge of a stack of gift tags and need to ensure that the position of the hole is the same on the top and bottom sheet.
What a pleasure it is knowing that there is such a helpful community of letterpress printers. Because of all of you, I am printing beautiful work that I am very proud of. Thanks so much.
Joshua
I just printed again with the flexible pins last night with a photo polymer plate. Works like a charm.
You should be able to find a local printshop or copy-shop that will be willing to drill a hole using a paper drill.
I just tried the hand-held drill, and I used a lot of clamp pressure. Using a wood-type bit left a fairly ragged hole. A sharp solid bit left a smooth hole, but the paper (1-inch stack of 20 lb bond) tended to stick together at the hole. Other types of paper will probably react differently. The only way to determine if the method will work to your satisfaction is to try it.
I have seen the technique in a number of books, including “How to Keep Your Volkswagen Alive” under the heading “How to Keep Your VW Book Alive Forever”.
NA Graphics sells a special “collet” which accepts standard paper drills and can be used in a standard drill press.
Thanks for the additional info. megahurt, I’m trying to find where I can buy the Megill Flexible Feed Gauges online. It looks like Excelsior Press may have some. Do you know who else sells them?
Sharecropper Press, thanks for the hole drilling info. I agree that my own testing is the best way to find the best solution. With that, I appreciate your sharing your results. I’ll keep you posted on my progress with it. I may need to outsource this upcoming job for now.
Thanks again.
Joshua