Thumbtacks on the Platten

I use a Craftsmen Superior 6.5 x 10 platten press.

When making ready to print, I generally print an impression on the tympan paper and then remove it to set my gauge pins up using the impression. While this will generally get me close, how precise it is depends in part on my getting the tympan paper back on the platten in the same place it was when the impression was made. This has been easier said then done at times.

As there are no registration points on the tympan or the platten, the only way to place it seems to be using the folds at the top and bottom of the tympan paper where it gets fastened down. It seems to me that there is potential for error here.

Now, I thought that if there were a couple of “registration pins” sticking up out of the platten near the edge that would pierce the tympan paper, it would make for more precise placement. I was reluctant to get the Hole Shooter out and drill holes for registration pins, so I thought maybe a couple of thumbtacks glued to the platten might work.

Has anyone else tried this?

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Easier to print a make-ready sheet. Take a print on a thin stock and when the platen is open mark the four corners through the packing with a needle or something similar. Lift up the top bale to open up the packing and paste your sheet in using the four holes for registration. All make-ready is now made on the make-ready sheet, use tissue and thin paste to build up the light areas.

If you find that the top sheet is slipping in the lower bale when you open it at the top, don’t be shy about using a little masking tape to secure it in place. This happens sometimes on the smaller presses.

DGM

The thing that worries me about pins or tacks is that you have a thing on the platen sticking out that will impede paper feeding, impede position of form (even if they’re at the corners it’s nervous to have an extra thing sticking out), etc etc.; and it sounds accurate, but really you’re dealing with a top sheet that is scored and folded etc etc, And you have the stretching from the tympan bales….

My favorite way to do it is to mark a sheet of normal tympan/packing with carbon copy paper, do the spot makeready on this, then bury the makeready sheet beneath some of the packing while keeping it in register with the form.

How? Stab location. Similar in ‘idea’ to your pins, but does not leave behind a physical item.

Fool proof? No, but with a little practice you’ll get good enough to nail a hairline position of your makeready sheet, way closer than you actually need.

I’ll lay the process out as I follow it below and I hope it helps you.

Once you gauge your paper and you determine the optimal packing, you can make a spot sheet and be able to locate it accurately with this method.

You need:
~A topsheet, secured in the lower tympan-bale so as not to come loose. A little tape can help with this, or just take care not to undo the lower bale or shift the top sheet.

~A sheet of your paper for the job, enough packing to create the desired impression.

~A sheet of carbon copy paper.

~A sharp exacto knife.

~At least one sheet of red pressboard should be under all your packing/part of the packing for the stab part of this.

You need to put all your packing- including the makeready sheet- under the top sheet. It’s best if the piece of red-pressboard is on the bottom, and if you can tape it along one side so it does not shift- by the way, this precludes the necessity of the top sheet being in the same place all the time. So if you’re worried it will move, just remember- the red pressboard you will use to locate your makeready sheet is taped in place to the platen.
So the red pressboard being on the bottom will also allow you ‘stab’ through the top sheet in three places lightly, into the red pressboard but not into your platen; which will be under your other packing sheets and the makeready carrier sheet.

The three stab spots should be placed so as to triangulate and accurately replace the makeready sheet later.
Again, as far as depth- this doesn’t need to go through to the platen; it’s pretty easy to carefully cut at three corners leading out from the center, small slits only a couple MM long will do the trick and they can go through the top-sheet, any extra tissues or packing sheets, and your makeready sheet.

Once you do this, undo the top tympan bale and then remove the makeready sheet, re-secure the tympan again, and then place the makeready sheet on the top sheet with the three slits aligned. Try your best to keep it aligned, tape it in place; add a sheet of carbon-copy paper or drawing transfer paper; add a sheet of your printing stock.
Tape everything in place with a little bit of masking tape and then pull an impression; you do not even need ink, the carbon paper will show you what is working and not.

The carbon paper will actually transfer to the makeready sheet, and show you the low spots; weak points; high spots; etc.
You can then take a little nori paste and some tissue paper and go to town on your packing underlay/makeready sheet, and the carbon paper residue won’t interfere with it sticking. Once you’re done with all your careful paste-up, you just undo your tympan bale and place your makeready sheet on the red pressboard aligning with the stab marks.

Re-secure your top sheet, add your positioning device of choice (pins, henry gauges, etc), and pull a trial impression.
If you need to change the packing or add more spot underlay, you’re able to do so even after the trial impression and re-locate it to the same spot.

A while back I had a web buddy who I would ask about things related to Linux. I always had to Google after getting an email from Mae Ling.

Google is still my friend.

Thanks for all the advice folks! Guess its going to be a Google and printing books weekend for me…

Already have a fairly dog-eared copy of my own. Making it more dog-eared. In 1972, it was one of my school text books… but that was 1972. It was, however, a good suggestion.

Your pins idea has ancient history, the old printers needing to to do really accurate register work on the old Albion and Columbian presses used the idea. I have on my own Albion. Look up Victorian Baxter Prints and prepare to be amazed! Indeed, letterpress folk all, do look up Baxter Prints, but don’t be tempted to give it all up to enter a monastery or nunnery!

Hi daleraby, Your post has me confused. I don’t understand why you need to remove the tympan just to set your gauge pins. Normally wouldn’t you make an impression, then measure your stock and draw lines on the tympan estimating position and then put the pins in approximate position and print a sheet of your stock. Looking at and measuring your printed sheet you determine which pins to move where and make your pin adjustments and print another sheet and continue until you have position and then lock down your pins. Packing is a different question but still shouldn’t require removing the tympan from the platen does it? Am I missing something?
What is the necessity of removing the tympan from the platen just to set the gauge pins?
If I am missing the big picture then I appologize. I was just reading your post and I thought the method didn’t make sense to me. I realize there are many ways to do some things so maybe I’ll learn something from this post.
Bruce

Honestly, it is more likely that I am doing something wrong than you. I havent’t done any real presswork since 1971 or so… how many years is that? I’ve forgotten most of what I knew and I never knew all that much. To make it even worse, we didn’t have photopolymer plates in 1971. That represents a whole new class of thngs to learn.

So far it has been just about as much fun as learning how to forge iron in a charcoal forge. I managed that OK, so I’ll probably acquire the knowledge and old skills for this eventually.

Thanks for the response… and for not lauging too loud at my more stupid commentary.