Daniel Reetz, the founder of the DIY Book Scanner community, has recently started making videos of prototyping and shop tips. If you are tinkering with a book scanner (or any other project) in your home shop, these tips will come in handy. https://www.youtube.com/channel/UCn0gq8 ... g_8K1nfInQ

Hardware buildup for a Sliding Glass platen scanner.

Built a scanner? Started to build a scanner? Record your progress here. Doesn't need to be a whole scanner - triggers and other parts are fine. Commercial scanners are fine too.

Is this buildup interesting? ( should I keep investing time in it, you can change your vote)

Yes, this is interesting work.
20
95%
No, I have heard enough from you to last a lifetime.
0
No votes
Don't care.
0
No votes
Not interesting but I love to hear you talk...
1
5%
 
Total votes: 21

james415
Posts: 13
Joined: 04 Mar 2014, 00:52

Hardware buildup for a Sliding Glass platen scanner.

Post by james415 » 07 Jun 2009, 19:49

Hello all.

I am going to publish the schematics for the glass platen scanner that I posted on instructables. I will also post photos to try to show how things fit together, but not details on each individual step. This is because I don't want anyone to be married to the tools I use or the exact construction choices. I hope to be able to convey an idea and methodology that can be used and extended by others.

Let me start with a brief explanation of my methodology. There are two constraints on this build up. The first is materials. There are no parts or steps in here that require special tools to work with. There are no materials that require special ordering or license. This is to ensure that nearly anyone who can read a ruler can build this as well. There will be portions that may cause some to exclaim, "Why doesn't he just use a plasma cutter/down draft table/laser CNC?" If you have these, go nuts. If you don't, worry not. You don't need them.

The second constraint was modularity. I am an engineer, so I always try to think ahead in the design phase. You should break down a design into a modular format that allows for entire portions of the design to be replaced/upgraded down the line. Think about an airplane. The engine is easily swapped out for a replacement or entirely different model on most planes. This allows for a simple, modular upgrade. We want the same thing here. That way when someone comes up with a new idea, lets say lighting, all we must do is pop off our light bar and replace it with his.

OK, so what are the modules in this design?

1. Base
2. Platen carrier
3. Platen locomotion mechanism
4. Lighting
5. Camera/monitors
6. Electronics and wiring

These can be further subdivided, but at the least make sure that no part in the design can be placed in two categories.

So, with that introduction I will starting laying out the steps.

First let's look at the finished product to make sure this fits your needs. Try to identify the modules. Hint some are missing from the photos for clarity (lights).

This is the scanner in the down position. Please excuse the bag of puffed kamut in the background.
IMG_0047_small.jpg
The completed scanner (down position)
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This is a photo of the platen raised. There is a ruler being used to hold everything still for the photo, but it is not part of the design or operation.
IMG_0048_small.jpg
Scanner in up position. (A ruler is used to hold the platen up for the photo)
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Let's start by looking at the platen.

Here is a side view of the platen carrier. This is what holds the glass. Think of it as a picture frame. The "ears" on the sides are to hold the sliding mechanism that we will talk about later.
IMG_0046_small.jpg
Platen Carrier
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Here is a picture of the top of the platen. In this photo it is installed with the rest of the hardware for perspective. Essentially, there is a frame of wood with a few strips of moulding to hold the glass in place. I will post a diagram that will show you exactly how to build it.
IMG_0051_small.jpg
platen topview
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Here is a detailed view of the platen carrier frame. This should show clearly how the molding holds the glass. Please note: there is no glue being used here. Remember modular. What looks like glue is a small piece of stickiness from the label that was attached to the glass. It came of easily later.
IMG_0030_small.jpg
detail of glass platen
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[This post will be updated as soon as I get a few minutes. Stay tuned.]


Cheers,
James

Cabe
Posts: 34
Joined: 04 Mar 2014, 00:52

Re: Hardware buildup for a Sliding Glass platen scanner.

Post by Cabe » 08 Jun 2009, 07:27

Looking really good, the sliding rails make for a nice smooth action.

I guess you just let the v cradle sit wherever it wants to, or are you intending to put a "milling table" style threaded rod control in there?

james415
Posts: 13
Joined: 04 Mar 2014, 00:52

Re: Hardware buildup for a Sliding Glass platen scanner.

Post by james415 » 08 Jun 2009, 08:54

Yes, I just let the book holder self adjust as I bring down the platen. It is so smooth, that in actual practice it nudges over just the perfect amount. This serves to completly remove one bit of work from your job.

Stay tuned for the rest of the buildup. Thanks for the feedback.

Cheers,
James

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daniel_reetz
Posts: 2786
Joined: 03 Jun 2009, 13:56
E-book readers owned: Used to have a PRS-500
Number of books owned: 600
Country: United States
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Re: Hardware buildup for a Sliding Glass platen scanner.

Post by daniel_reetz » 08 Jun 2009, 09:09

This is great, thanks! I asked Rob to do something about the way the pics are displayed. It's awesome to have such huge pictures, so I hope we'll be able to see them all.

spamsickle
Posts: 596
Joined: 06 Jun 2009, 23:57

Re: Hardware buildup for a Sliding Glass platen scanner.

Post by spamsickle » 08 Jun 2009, 17:10

Since Daniel posted the link to the Canon store, with cheap refurbished CHDK-capable cameras, I thought I might go ahead and get started with an upgrade to my book scanner. What I notice in the specs for those cameras is that the "normal" focus needs about 18" to 20". Obviously, macro focus will go closer, but on my cheap camera, macro focus and manual focus are mutually exclusive. If I'm planning to attach the cameras to the platen (and, at this point, I am), I either need to plan on making the sides big enough to keep the camera far enough away to focus in normal mode, or plan on shooting in macro mode. Does anyone know which of these Canon cameras (if any) permit manual focus in macro mode? Or, does CHDK enable manual focus in macro mode even if the original camera doesn't offer it?

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daniel_reetz
Posts: 2786
Joined: 03 Jun 2009, 13:56
E-book readers owned: Used to have a PRS-500
Number of books owned: 600
Country: United States
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Re: Hardware buildup for a Sliding Glass platen scanner.

Post by daniel_reetz » 08 Jun 2009, 17:48

I'll have a look at my A590's tonight, I have an A530 I'm planning to send to Suryandaru, too, but I don't know if I'll have the time to install all the software and hack around with it.

Not terribly helpful on my part, but I suggest you simply mount them far enough away to use the normal focus.

you1
Posts: 92
Joined: 04 Mar 2014, 00:53

Re: Hardware buildup for a Sliding Glass platen scanner.

Post by you1 » 08 Jun 2009, 19:11

Hi James,

Great job on the glass platen design.
We can now attach cameras to the "ears" with focus locked; no more focus issue on partial pages.

Q: How heavy is the moving system? It looks a little heavy after few hundred pages :)
A counter weight might be beneficial.

Best,
Edvin

james415
Posts: 13
Joined: 04 Mar 2014, 00:52

Re: Hardware buildup for a Sliding Glass platen scanner.

Post by james415 » 08 Jun 2009, 19:18

It is actually really light, about 3 pounds. That being said, I do have a counter weight that I have been playing with that makes it much easier. I am trying to figure out if it is better to be neutrally buoyant, or have a slight drag down/up. I am leaning toward a slight drag up, as my arm likes to pull it down rather than lift it up.

If you want to try it, make sure you use something like high test fishing line. This way the weight of the cable will not result in variable resistance.

Cheers,
James

you1
Posts: 92
Joined: 04 Mar 2014, 00:53

Re: Hardware buildup for a Sliding Glass platen scanner.

Post by you1 » 08 Jun 2009, 19:47

Keeping in line with modularity,
we could use some kind of weight disks (say large washers from a hardware store);
which will allow for discovery of personal preference.

It's going to be some time before i can make the above system. I'm currently working on a software/script for the cameras to give us some more options with regards to the "remote" button.

-Edvin

you1
Posts: 92
Joined: 04 Mar 2014, 00:53

Re: Hardware buildup for a Sliding Glass platen scanner.

Post by you1 » 13 Jun 2009, 01:21

Hi James,

I will be attempting a variation of the glass platen in a couple of weeks; needless to say, I will be utilizing many of your contributions. :)

Q: Have you mounted your camera's yet :?:

I intend to extend the vertical part of the ears that are connected to the rollers; and mount the cameras on them. I intend to only allow for vertical adjustments of cameras, and securing cameras at 45 degree angle. I will credit this to Jardi, where in one of his comments he had posted an image (see attached).

Daniel mentioned that there is a reflection issue to worry about; however, as he mentioned in a different posting the camera setting and the light intensity drowns out the reflection; so I think it should be okay.

This design, allows for focus to be locked, and every image capture to be in focus (regardless of partial content).

-Edvin
Attachments
fixedCamera.JPG
fixedCamera.JPG (35.58 KiB) Viewed 17307 times

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