Thumb Thing In The Way She Moves...

[StevePoling]

(sorry, the pun's been going through my head the whole time I've been messing with these.)

You can find pictures of my Mark-One duck-tape-and-cardboard design for platenless operation. To recap. I had the idea of wedging pages open using a triangular dowel. (Not a good idea. http://diybookscanner.org/forum/viewtop ... t=10#p1999) Pages can bend up and mess up the shot and the triangular dowel is not practical for books with narrow gutters.

Dan suggested an Italian device called a "thumb thing" which I mocked up and it worked well enough to digitize one book with it.
http://diybookscanner.org/forum/viewtopic.php?f=1&t=236

I decided to assemble a Mark-Two version from steel and plywood. I had laying about some model aircraft plywood and cut an 8" square thereof. This was then cut on a diagonal to create 2 right-triangles. In the right-angle of each I cut a narrow slot.

I've replaced the square 3/8" dowel with a rod from a filing cabinet. If you're unlucky, your filing cabinet has racks on the side of stamped metal that pendaflex hanging files are suspended from. If you're lucky, you can find a narrow steel rod that's part of an arrangement that sits within the drawer, and then files can ride thereon. It makes for a nice stiff rod that will prevent the triangles from rotating about it. The slot in the plywood triangle is to accommodate this rod.


To secure the rod to the triangle, I used black drawer liner material left over from building the VST (vee-shaped thing) described in Dan's instructible. (I also used moped tire inner-tube, but that did not work as well.)


This material is secured to the triangular thumb thing by pinching it between two metal straps. I cut in half two 4" corner braces for each triangle to serve this purpose. These metal straps are then bolted together using inch-long 1/4" bolts.


A word of advice to anyone who's interested in building a scanner. Whenever you think you can't find that one key thing you need visit your local Hobby store. Ferinstance, they can get you methylated chloride when it comes time to weld plexiglass together (after you've digitized all your wide-gutter books and you decide to build a platen).

[benjamin]

How are you addressing the sliding rod issue discussed in your last thread? I was thinking about something similar and wondered if maybe you could drill out the rivets from two bar clamps and combine them. Mine are all in use, so I can't take an easy picture, but here's a (sloppily) highlighted detail. One locking adjuster on each side, remove the handle on each & replace it with the v- (or wing-) shaped angle... just a thought.

[StevePoling]

How are you addressing the sliding rod issue discussed in your last thread?

I'm not quite sure I understand your question.

Each triangular part is slotted with such that the rod just barely fits. It doesn't want to slide. Moreover, the black rubber wrapped around the outside doesn't encourage sliding either. So I work the rod onto the triangle, as soon as I get enough rod through that I can get onto a clamp, I put the rod in a bench vice and then I use two hands to tug the triangle to the desired point.

I think that had I used a bigger rod, such as one found in the clamp you pictured would intrude into the page for all but the widest gutters. This rod is only about 1/8" by about 3/8" and I hope similar rods can be found in an office supply store.

If this doesn't address what you're talking about, please elaborate your question a bit.

[benjamin]

That makes total sense. Well done!

...also, good call on the hobby store! Headed out tomorrow, Turns out model trains use all kinds of interesting electrical components.

[StevePoling]

...also, good call on the hobby store!

Word of caution: Hobby stores sell all sorts of really neat things. Neat. Distracting. Things. I made the mistake of buying a jigsaw puzzle when I got stuff for my scanner last Saturday.

After I finished the Mark 2 Thumb thing I got sucked into doing the jigsaw puzzle.