Categories
Uncategorized

Ink Pads

Single drum rotary and hand-printing mimeographs use ink pads to either convey the ink from a reservoir or hold applied ink in place (acting as a de facto reservoir), so that it feeds through the stencil onto the paper in a controlled manner. They’re of relatively basic construction – and my guess is that it’s for this reason that patent information about ink pads is relatively scarce. I was able to find two A. B. Dick patents, each referencing “improvements” to already existing patterns.

This second patent is interesting because in advancing its improvement it also explains the typical method for printing multiple colors without changing out the ink pad and cleaning out the reservoir. The method entails using a blocking sheet over the primary ink pad to “restrain” ink of the first color so that a second color, spot-applied to a second ink pad can be used temporarily. I’m not sure what the blocking sheet would have been made of (plastic or rubber or ??), but it’s an interesting technique that might be of use.

While every duplicator brand had its own ink pad specifications, I hope that the information I provide here will help you improvise an ink-pad pattern for your own machine even if its dimensions are different from what I post.

From what I’ve seen so far (on my three Heyer machines), flannel is the fabric of choice. I did see a passing reference in a 1937 issue of Popular Mechanics (I couldn’t figure out which exact issue, the search just pulled up a phrase by itself) that mentioned cambric used as an ink pad. Cambric is a densely woven cloth, initially made of linen. I don’t know if it was made of something else by 1937. But, cotton flannel is certainly easy to come by these days – if you have an old flannel shirt you’re willing to sacrifice, you can cut ink pad pieces from it, so I think it’s safe to just stick with that.

I am lucky enough to have unused pads for each of my machines, so before I gunk them up with ink, I’ll be measuring them and noting any construction techniques that seem relevant.

Since I already had flannel on hand and none of my household’s flannel shirts were in bad a enough a state to require upcycling, I am using the new flannel to make extra ink pads for my Heyer 60. In this post, all my photos and measurements relate to this machine’s ink pad.

Heyer Lettergraph Model 60, disassembled.

To remove the ink pad, unscrew the bolt at the center of the handle. The handle serves to lock the inkpad in place with a small amount of tension generated by a metal bracket seated under the handle. Unscrewing the bolt and removing the handle releases this tension.

The bracket hinges on a pin that is inserted into a narrow “envelope” sewn into the ink pad. Release the wire clasp that serves to snug the stencil (not shown) to the pad and you can then lift the ink pad from the mimeograph. Remove the pin and set it aside.

Feed the ink pad through the slot on the opposite end of the mimeograph. The anchoring bar can then be removed from the ink pad.

Congratulations, you have loosened your ink pad.

A new one can be made following the measurements of the original. It consists of a rectangle of flannel that is a finished size of 5×5 inches (but see caveat below AND see the section on “sizing your ink pad” for other important considerations!). The sides are unhemmed but are finished with a backstitch to prevent fraying. The top and bottom are hemmed so as to provide “envelopes” to accommodate the pin and the bar.

The underside of the ink pad is lined with a 4.25×5″ rectangle of 3mm-thick felt.

The two pieces of fabric are joined together at the “envelope” seams (so, in constructing a new ink pad, you can sew the felt on and hem the “envelopes” at the same time.

To make a new ink pad, cut felt and flannel to correct sizes.

  1. The felt piece will not be hemmed or otherwise folded, so it should be cut to its finished size (4.25×5″). See photo “#1,” below.
Photo #1. Though I ordered 3mm-thick felt (blue, in contrast with the original black), it is actually 5mm thick. We’ll see if it matters.

2. The flannel should be cut larger than the finished size because two ends will be hemmed to create “envelopes” (so, it should be somewhere around 6.5×5 or 7×5 inches before sewing). Here’s the caveat: because my felt is thicker than 3mm, my finished flannel pad will need to be longer than the original (to accommodate the extra thickness of the felt). You may need to keep this in mind for yourself. (And you should still read the “sizing your ink pad section” before you start)

3. Stitch the “long” edges of the flannel piece (do not fold, just do a backstitch as near to the edge as you can) to prevent fraying. See photo “#3”, below. If your fabric is very prone to fraying, you might sew a blanket stitch along the edge, instead or in addition to the backstitch.

Photo #3 – showing the backstitching parallel to and near the edge.

If your piece of fabric incorporates the selvage, the woven end of the fabric, there’s no need to backstitch that edge as a selvage will not fray. See photo “#3.1,” below.

Photo #3.1: It’s hard to tell, but this is the selvage edge of my flannel.

4. Fold the short ends over so that the main section measures 5 inches. Pin or baste to hold. Basting is to be preferred because pins introduce folds – when you get to the point where you’re stitching the second side, you’ll want the ink pad partly loaded on the mimeograph to assure correct fit, and basting stitches will allow this more easily than pins. Baste or pin the felt to the side of the ink pad that hosts the folded-over flannel sides. See photos #4 and #4.1.

Photo #4: Set the felt on top of the folded-over edges. Here it’s not yet been lined up so you can see the folded flannel edges.
Photo #4.1 Lined up and attached with a basting stitch.

5. Stitch one side of the felt to the two layers of folded flannel using a backstitch (not a running stitch as in basting). Keep the basting stitches in place on the other side. Install the half-done ink pad to see if it will fit or if the flannel needs to be adjusted.

At this point, I found that the thick felt made reinstalling the ink pad inconvenient. I had to force my small flannel “envelope” into the space and almost couldn’t get the metal anchoring bar into what little fabric peeked through. There are adjustments that I can make to subsequent inkpads to assist reinstallation, but I did get this to work as is.

It became obvious, though, that in spite of keeping my measurements correct, the new ink pad will be ever so slightly too short (this is because the felt is thicker than the original), so I will increase my flannel’s finished length to compensate.

6. Make any adjustments you deem necessary, stitch the last edge, then reassemble your mimeograph.

The new ink pad installed on the Lettergraph.

Sizing your ink pad

This tutorial was based on an original, unused Heyer Lettergraph 60 ink pad. In preparing to use my first stencil, however, I found that the original design’s measurements would not allow ink to fill a standard postcard-sized piece of paper to its edges (in the US, commercially available postcards are 4.25×5.5 inches in size – conveniently, this is one quarter of a standard letter sized piece of paper [8.5×11 inches]). The mimeograph body can accommodate that size, but for some reason the original ink pad is narrower than the mimeograph body.

My first stencil is going to be a template for Lettergraph 60 stencil headers – the card header that allows the stencil to be mounted on the duplicator:

Stencil header.

You’ll notice that it’s wider than the 5.5 inches I have available to print on. By making the templates a quarter inch narrower, I’ll be able to print them on postcard stock. Unfortunately, because my ink pad is only 5 inches across, there’s half an inch of my stencil that won’t receive ink:

The template, which, as you can see, extends past the ink pad. This is a problem.

In order to achieve ink placement across the entirety of a postcard, I’m going to have to make a larger ink pad. I’ll keep the ones I’ve already made to use with color inks when they’ll only appear in the interior of postcard images. My new ink pad will be designed to fit 5.5 inches of the width of the mimeograph (out of a total width of 6 inches). Since I’ll be applying ink manually to the ink pad, it won’t matter that the perforated ink-flow-through section is significantly smaller than the ink pad.

Here are photos to show the Heyer’s original ink pad in relation to its metal mimeograph frame. These will help you get a sense of the relationship between the perforated ink flow-through section and the felt layer so that you can experiment and come up with your own ink pad pattern. The felt layer extends from edge to edge (top to bottom) along the face of the mimeograph but is narrower than the metal frame (left to right). The felt and flannel extend about a quarter inch beyond the ink flow-through section in the other direction but do not extend the full 6 inches all the way across.

As I’ve not yet tested this mimeograph, I can only offer my theory that a felt layer will be useful in cases when you don’t want to fill the ink reservoir, because it allows the ink pad to hold more ink than it would if it were just a single layer of flannel. Since I’ll be making my first prints with unthinned Riso ink, I’ll be applying ink directly to my ink pad.


Addendum

  • A double layer of flannel can be used if no felt is available or desired.
  • If your flannel has an obvious “nap” (with one side fulled [fluffed] more than the other), the fluffier side should be up for paste ink. The smooth side should be up for liquid ink.