bnz's new standard build thread

[bnz]

Hi all,

well, I guess my build thread is probably not very interesting - at least right now since I am (more or less) building what Daniel has suggested - without the exact measurements. I may add some counterweight later-on if I see the use. After two evenings, I have finished my cradle. So here are the first few pictures.

As you can maybe see, there is already a small problem with the measurements, namely the base of the cradle is not quite long enough horizontaly and there is little space between the moving base plate and the blocks holding the cameras. It is maybe not a big problem and fixable, but nevertheless a little annoying.

One thing I did a little differently (at least I think so) is that I used one single piece for the back board holding the platen. To keep it dismountable, I put some bolts in there first with the nut inside the wood and put the slides on top of it. I did the same for the boards holding the cameras.

One more thing noteworthy is maybe that I had our hardware store cut the MDF boards and the triangles. This is a nice free service most hardware stores have in Germany and I am pretty happy that I at least had these measures ready in advance.

I'll update as the build proceeds...

[bnz]

Third evening. Today, I finished the platen and the backboard mechanism for pulling the platen up / the column. Here are some pics:

Now that I came this far, I see a couple of problems:
- The whole thing isn't very stable. I somehow need to stabilize the back board holding the platen. The trouble is, I wanted to keep this back board dismountable. I don't have any clever idea to have it dismountable and stable at the same time.
- The platen is _very_ heavy. It is impossible to pull it up and down from the handle. This is so much worse than I expected. I am guessing that is why most other builders of the new standard added some sort of counterweight.

Cutting the plastic glass was really a mess. I don't know how you guys did it. We tried a jigsaw first and the plastic kept melting and the blade got stuck. After that, my father came along with his favorite tool which kind of worked. I'm sure that's not how most people do it though

[daniel_reetz]

Cutting the plastic glass was really a mess. I don't know how you guys did it. We tried a jigsaw first and the plastic kept melting and the blade got stuck. After that, my father came along with his favorite tool which kind of worked. I'm sure that's not how most people do it though

if the plastic was melting, your jigsaw was probably running too fast or had a dull blade. Usually to cut plastic a circular saw or table saw (or handsaw) is used... sorry you've been having troubles. Also many people have just had their plastics cut at the plastics shop or hardware store.

[reggilbert]

Cutting the plastic glass was really a mess. . . . the plastic kept melting

One of the posters on this forum. I think clemd973, but I couldn't find it in his main build tread, said it was essential to use soap or something on the blade when cutting acrylic with a power saw

[bnz]

Happy new year everyone! Thanks for the answers. Well, a table saw would probably be ideal. Anyway, we managed to cut it somehow. I'll have to lookup the soap hint though again.

So, it turned out that a big problem with respect to handling the platen was that the base was too unstable. It already started to work once we put two metal brackets into the inner side of the base to stabilize the back side with the column. Stability is still a general problem though. We're thinking to improve it further by screwing another plate to the bottom of the base and maybe to stabilize the back column with another metal bracket or a triangle.

Yesterday, we added additional counterweight though. A very very simple construction and only temporary to test it:

The weight is 2kg and it seems to be enough to handle it properly.

I am still very unhappy with the camera supports on the left and right. As I wrote earlier, in the original construction, they were too close to the moving cradle. I tried a simple construction with bigger metal brackets, but these vibrate a lot. Therefore, I screwed the original wood camera supports to them, but it didn't help much. I keep thinking that the general idea to mount the camera supports to the cradle is a bad idea as the platen is handled all the time and it will always cause some sort of vibration toward the camera. If they are independent from the cradle, I guess they'll likely catch less of that vibration from the platen handling (of course depending on where the cradle stands). So maybe I'll just look for another solution here.

For the light, I currently just mounted a single 120w halogen lights which already seems pretty good. I want to add the second one anyway though. Regarding reflections: so far I haven't had serious problems with that and I am pretty happy with my polystyrol glass. Here is a pic of my current (temporary) result:

As you can see, I don't currently have a second camera. I'll get a second 550D/T2i once I can afford it and once I have a good solution to take the photos using tethered shooting from two cameras at the same time. We scanned a whole book yesterday and I am pretty happy with the results. Here is a sample:

0277-scantailor.tif

(175.88 KiB) Not downloaded yet

[Shaknum]

This looks really nice. You're getting some really nice and crisp pics. Great work.

[bnz]

Thanks. Well, it is a good camera I haven't even started to optimize my camera settings and lens. I expect the result to be more consistent with an additional light and when I take care of the vibration problems.