Project Photofly is a program and a web service, which lets you convert a series of photos of an object into a 3D mesh.

I gave it a quick test.

I made around 50 photos of a small double headed figure (around 20 cm high) and used the tool to create a 3D mesh from it.

This is the result:

Here is one of the photos:

I'm really surprised how easy it was. After reviewing the photos (and rejecting a couple of them becouse they were too dark) I just imported them into the Autodesk tool. The photos get uploaded into the cloud and after a short while the result can be downloaded. And the result was great! I didn't do any manual editing in Photofly whatsoever, the photo/camera positions where all calculated correctly. After exporting the mesh (it contains textures too, but for 3D printing I'm not interested in them) I loaded it into netfabb Studio. The mesh was pretty much complete, only one bigger hole under the chin where I didn't provide enough info with the photos it seems. Besides that there were only smaller holes, all of which could be automatically fixed by netfabb. I just had to cut off the base and now I have a great watertight 3D model.

Really promising, given that was my very first try.

 

Here's a video showing how you should take the photos:

Printed the fantastic Penrose Triangle Illusion by chylld
The illusion works even better on video:

http://www.thingiverse.com/thing:6513

I have upgraded my RapMan with a heated print-bed and needed a modified z switch holder (the z switch normally is mounted directly on the print bed, which is not a good idea if it is heated). I tried Laszlo's one, it works, but I had problems with it. It is attached to one of the 3 screws the print bed is hold by. These 3 screws are equipped with a spring mechanism, allowing the print bed to back down if the print head by error tries to go down below the print bed surface.
When attaching Laszlo's z switch holder, this spring has no effect any more. Laszlo says he doesn't have the problem and I think the reason is that I have a RapMan version 3.1 while he has a previous version. My RapMan z stage platform has threaded holes for the 3 screws I was talking about which seem to be the reason for problem.

Anyway, I designed a different solution, where the z switch is not attached to the print-bed but to the z stage platform instead. This also makes fine-tuning the print-bed/extruder distance easier. You can do that with the 3 screws now and you get direct feedback about the new distance. Before you had to turn the distance screw at the print head and run a home sequence to get the new adjusted distance.

With this new mechanism the z switch is not pressed directly, but there is a arm which presses it. The arm reaches up where the distance regulation screw comes down during the home sequence.

Here you see my RapMan with the heated print-bed and the new z switch mechanism in the left back corner:

Here a couple of close-up photos. In case you wonder, I added a bit of duct tape because I needed a M3 screw to hold the arm and the only one I had left was a bit too short, so the duct tape holds it in place :-)

The OpenSCAD and STL files for the 2 printed parts can be found on thingiverse.

It is already a couple of weeks since my heated print-bed from László arrived. I was busy so I didn't find time yet to update the blog, but finally here is my experience with building and installing it.

The print-bed is made of aluminium. It's heated from the bottom side using power resistors. The print is done on a Kapton-covered steel sheet which lies on to the of the aluminium bed and which is hold in place by powerful magents.

The bottom side has threads to attach 9 power resistors and pits where the magnets will find it place. First I covered it with Kapton tape, cut out holes for the resistors (I only used 5 in the beginning) and the magnets:

Then I added the magnets.
U/D stands for up/down for the orientation of the magnets.

László recommends to add iron bars on top of the magnets. This makes the magnetic force stronger. Neodym magents don't stand heat that well, but short-cutting them with the iron bars also seems to improve this.
I decided to mount all 9 resistors I ordered at that point, so I added the remaining ones too:

Then I wired the resistors. For a start I was only using 6 of them, this is why the middle 3 are not conencted. Here the 3 mounting screws an the z-switch holder are already added as well.

I tested the bed in this configuration, but it was not getting hot enough. Even with all 9 resistors it hardly reached the temperature where ABS sticks to the steel sheet, which should be at about 100-110°C.

So the next step was to add heat insulation. To prepare that I added the heat-resistant insulation for the connecting wires. I chose not to wire all the resistors together but have two groups with 6 and 3 resistors to have more possibilities later.

Then I covered the bottom side with the rock wool. I also attached a thermistor to the bottom side of the bed, so there are now 5 wires coming out there.
Shouldn't have done this in our living room really, it's quite a mess. I'm lucky I have an understanding wife.

OK, now the bed was ready to be installed. Removed old bed, replaced it with the new one, attached the power transformer, covered the steel sheet with Kapton.
I wasn't happy with the z-switch holder, so I replaced it with a newly designed one (more in an extra post later).

Turned out that the temperature now was ideal for printing ABS. I now always switch the print-bed on about 5 minutes before the print and leave it on for the whole print. With all 9 resistors connected (all parallel) the power transformer which comes with the kit is a bit too weak by specification. It gets a bit hot, but it works fine. I'll probably add a fan for it later.
I didn't measure the temperature, but the ABS sticks very well on the Kapton. I didn't have to do anything (like sanding) to improve the adhesion.

Here's a finshed print (lots of strings, but that's not the fault of the print bed). I'm using the scraper which came with my RapMan to remove the steel sheet (it's not that easy, the magnets are really strong). I added small pieces of card-board on both sides of the scraper so that I do not burn my fingers.
When the print is cooled down a bit you can remove it from the sheet.

Right now am really happy with the print bed. Its a bit costly, but it is nicely made and very flat. And it probably cannot be made cheaper really. You would have to go for a different approach like a circuit board, but I haven't seen one which covers the full RapMan print area.

I do not sand the Kapton, so the bottom faces of my prints are really nice, flat and shiny. I did not have any warping issues any more when using it.
I didn't print really big objects yet, this is one of the next things I will test, but I do not expect problems.

 

 

I ordered a heated print bed for my RapMan from László which arrived today.
Here are some unboxing pics. Looks promising!

Time to upgrade my RepMan firmware. Version 3.0.0 should be out soon.

I had a couple of objects where I wanted a really flat, clean bottom side, which is hard to archive when printing on a raft with your RepRap/RepMan. So I wanted to have one of these heated printbeds where you do not need a raft - the objects stick to it directly and due to the heat they do not shrink while printing avoiding the warping problem ABS has which would cause the edges to come off the printing surface otherwise.

But I did not like spending lots of money in a machined metal table. I'll probably will get one now, but for trying it out and playing around I looked for something cheaper.

So here is my (roughly) 10$ heated printbed design. You need:

• flat piece of wood board
• a proto-board with stripes (something like this)
• Kapton tape
• old PC power supply

I soldered bridges onto the protoboard so that the whole board is covered by one long zig-zag ciruit. With my board size of 160x100mm (Euro card size) this resulted in about 2.5 Ohms. Attaching that to 5V resulted in about 60°C which is is not enough, but with 12V it was at about 90°C, which proved to be enough.

I covered the board with Kapton so that the holes are covered and ABS sticks much better to it. I mounted the proto-board on the wooden board using little wooden pieces as spacers which I covered with a few layers of Kaption tape for insulation. I wrapped some Kapton all around the proto-board and the wooden board which proved to be enough to hold it in place. I glued the wooden board onto the print bed mount of the RepMan using double-sided take. Pay attention to what take you use, mine was really hard to get off again.

In case you wonder, my proto-board was broken, so I soldered it together again. Made a bit of trouble, because it was not flat any more.

 

So does this work? Yes, I was able to print a couple of nice objects with it.
However, there are a couple of cons:

• The prints stick really well. This is good, but you have to wait for the printbed to cool down before attempting to get the print off, otherwise the object will get bent. Once I was ripping the proto-board off the wooden board while trying to get the print off. Also the Kapton tape came off easily.
• I had problems to get the printbed flat. Mostly because of the broken proto-board so that probably a problem that could be avoided easily.
• 100x160mm is enough for many objects, but if you have a RepMan you could do much larger prints. When using larger proto-boards the resistance will be different, so you need either a higher voltage or you need a different way to connect the stripes on the board. Either way you probably need a higher rated power supply.
• The proto-board started smelling funny. I think it was a really cheap one (don't know, I used one I had lying around) so this could be avoided by using a better, more heat-resistant one.

It was a fun experiment and useful for smaller prints. But I guess I get something better now.

For the Germany-Spain game tonight I printed this. I just need some
gold paint now...
You can download the STL file at http://www.thingiverse.com/thing:3494

Update: after painting it with gold spray paint and adding the dark green stripes, it looks like this:

Print quality still could be better, I had lots of "strings" to remove. While doing this, one wing broke off (I glued it back on).
The thing was printed in 2 parts. Gluing them together did not work as well as I hoped as the pieces had quite some warping.
Maybe it would print better in PLA instead of ABS.
But hey, the kids like it! :-)

The STL and the OpenSCAD files are now on thingiverse: http://www.thingiverse.com/thing:3177