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

Red shift...

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.
cfmorrill
Posts: 56
Joined: 17 Apr 2011, 21:20
Number of books owned: 0
Location: Charlottesville, Virginia

Re: Red shift...

Post by cfmorrill » 19 Dec 2011, 20:01

Hey ateeq,
Sorry I don't remember. I'd go measure it but I'm home now and the build is happening at work. Will try to get that for you tomorrow.

I did run across a possibly cool solution for holding the panes apart in the case of spiral bindings. Lowes has some nylon 1/4 X 20 bolts. I'm going to run a tap straight into the plywood at the front of the machine in a couple places just opposite the platen panes. Next, I'll screw two nylon bolts to contact the edge of each pane. Ought to hold them right where I want them, either together or just apart to make way for any weird bindings. Might do the same on the back side of the machine as well. Probably ought to tap the holes fairly high up where the panel is close to being supported by the crossmembers.

ateeq85
Posts: 67
Joined: 08 Oct 2011, 17:39
E-book readers owned: IPad 2
Number of books owned: 60

Re: Red shift...

Post by ateeq85 » 21 Dec 2011, 09:49

In GaryK's build under the files he released he released there was a page named fixtures, none of these pieces seem to from the original build Dan did and I can't figure out what they are for, do you know? All of these pieces seem to take bearings too. they have to be for something it's a few of them

User avatar
daniel_reetz
Posts: 2779
Joined: 03 Jun 2009, 13:56
E-book readers owned: Used to have a PRS-500
Number of books owned: 600
Country: United States
Contact:

Re: Red shift...

Post by daniel_reetz » 21 Dec 2011, 11:18

Fixtures are holes that you cut in the main board. You put another piece in them that you cut from somewhere else- say, a lifter arm - and you use the fixture to hold it in a known location so you can pocket it or do some other operation on it.

ateeq85
Posts: 67
Joined: 08 Oct 2011, 17:39
E-book readers owned: IPad 2
Number of books owned: 60

Re: Red shift...

Post by ateeq85 » 21 Dec 2011, 20:37

Have you seen the files that you recently reported from GaryK's design perhaps you can figure out what those pieces may have been under the pictures zip. The title of the page they are on says fixtures however it is four pieces that were not in your build with the skate board bearing pockets in them so I am guessing maybe they were for a piece that had some movement involved.

User avatar
daniel_reetz
Posts: 2779
Joined: 03 Jun 2009, 13:56
E-book readers owned: Used to have a PRS-500
Number of books owned: 600
Country: United States
Contact:

Re: Red shift...

Post by daniel_reetz » 21 Dec 2011, 21:17

Yeah, I will have a look at the files tomorrow or this weekend. Tonight I have to help a friend move. If you feel like uploading your copy here so others can examine them, please do.

ateeq85
Posts: 67
Joined: 08 Oct 2011, 17:39
E-book readers owned: IPad 2
Number of books owned: 60

Re: Red shift...

Post by ateeq85 » 21 Dec 2011, 21:36

here is what i was taking about right here
00 Fixturing.jpg

dpc
Posts: 304
Joined: 01 Apr 2011, 18:05
Number of books owned: 0
Location: Issaquah, WA

Re: Red shift...

Post by dpc » 21 Dec 2011, 22:59

I believe that area is used to index the parts cut from the other sheet so that you can flip them over, drop them in the cut-out in the fixture area of the second sheet and then the router will cut the bearing counterbores on the backside of these few parts in the correct position.

So you'd cut all the parts out of the first sheet, put the second sheet on the CNC bed, make the cut-outs in the fixture area. Pause the CNC, drop the parts from the first sheet into the cut-outs (flipped), and then start the CNC again and cut the c'bores along with everything else on the second sheet.

That's my guess, anyway. Dan, or any of you other CNC jocks, please correct me if I'm wrong.

ateeq85
Posts: 67
Joined: 08 Oct 2011, 17:39
E-book readers owned: IPad 2
Number of books owned: 60

Re: Red shift...

Post by ateeq85 » 22 Dec 2011, 05:02

So your saying they a sort of tracing piece to guide on the cnc for some of the pieces . So these pieces don't have any use once the pieces are done being cut and pocketed.

dpc
Posts: 304
Joined: 01 Apr 2011, 18:05
Number of books owned: 0
Location: Issaquah, WA

Re: Red shift...

Post by dpc » 22 Dec 2011, 12:59

Correct. The pieces that are cut out of the fixture area would be discarded as you only care about the cut-out (the hole) left in the sheet.

Also, even though the counterbores are marked on the pieces that are being cut out from fixture area and then discarded, you won't be machining counterbores on those pieces. Those markings represent the portion of the CNC instructions that will be executed once the actual arms/levers/etc. are placed into the respective cut-outs in the sheet in order to make the counterbores on the flip side of the parts.

cfmorrill
Posts: 56
Joined: 17 Apr 2011, 21:20
Number of books owned: 0
Location: Charlottesville, Virginia

Re: Red shift...

Post by cfmorrill » 22 Dec 2011, 18:56

Ateeq,
I measured the glass size, sorry to have missed a day. The two main upper panels are about 13 inches apart or thereabouts. Sketchup plan shows 13.060 hmmm. Don't know why. The grooves are about a quarter inch deep. The grooves to hold the glass are about 11.25 inches long. I am planning to make my platens 1/4 X 13 3/8 ths X 10 1/2 so I've got room to slide them back for weird bindings. I thought I would start off with plastic so if things don't exactly work, I can cut the platens down a bit. Plus, the local glass place has a lot of plastic scraps and I can get sometimes get them real cheap.

When ordering actual glass for windows I usually order it 1/8th smaller than the opening. Glass usually comes in a snit larger than ordered.

Hope this helps.

Charles

Post Reply