Wednesday, October 15, 2014

Building my own 3D printer part 3 and the first video


My 3D printer had its first test run last night.  So far I need to replace the X axis stepper motor it has a bad connection inside of it somewhere as can be seen in this video on Youtube.

http://youtu.be/s77h1BQ-EVQ

Here is a picture of the jumpers to convert the Ramps board to a printer 25 pin interface.  I only connected to the pins that I needed for X, Y, and Z for Step, Direction and Enable, they are blue, green and yellow.  The enables are all connected to ground.  Then I also needed to connect to ground and 5 Volts, they are yellow and red, the top two connections..


Here is another video of the DIY 3D printer this time it is running with and Arduino Mega.

http://youtu.be/YemKKhmJT2o

Here is a picture of the Ramps wiring.  The heat bed is not wired up yet.


Tuesday, October 7, 2014

Building my own Mendel 90 3D printer part 2

My 3D printer is coming along quite nicely but slowly.  I have started doing the electrical wiring as can be seen in this picture.  Notice the custom made aluminum motor mounts and the use of standard "off-the-shelf" parts throughout.  My next book will give the details of construction it will be titled "Inexpensive 3D Printer Projects".


I purchased standard ends for the X-Axis ends but I have come up with plans as to how to make my own X Axis ends.  I really think even the X Axis ends can be made with standard parts and a piece of Plexiglas or aluminum to hold it together.  The only tricky part would be the "Nut bracket".  That could be made out of Plexiglas.  Just drill a 1/2 inch hole in it and then melt the 5/16" nut into the hole.

Here is a picture of my homemade X axis carriage.  I had to cut the 1/2 inch pipe supports to fit them in the space available (There is approx 2.05 inches between the rails).  The two holes at the back are for mounting the Extruder. The holes at the front already existed but they are for the belt clamps.  The center hole was just a little over 1.25 inches in diameter but it was not big enough to lower the hot end down through.  I had to disassemble it and reassemble it through the hole.  I need to cut off 1/2 inch at the front as it is not needed.

It is almost done!  Just the 25 pin connector at the bottom right and the heatbed to wire up and it will be done.  Here is what it looks like at this point.





Tuesday, September 23, 2014

Building my own 3D printer based upon Prusa and Mendel90 designs

I have been trying to build my own 3D printer.  I am trying to use "off the shelf" parts as much as possible. I did end up buying X axis ends on eBay.  I designed and made my own stepper motor mounts.

Here is a picture of the frame as I first assembled it.  The blue tape is so I can write on it for my hole markings.

Right now I am stuck on the lead screws for the Z axis.  The holes for the nuts are .55 inches across and they are supposed to be for 8mm nuts.  But 8mm nuts are .51 inches and 5/16 nuts are .5 inches. Both nuts rotate freely in the hole as the hole is for a nut that is .55 inches across.  The nuts that are found on hollow electrical threaded pipe commonly used in table lamps fit perfectly.  One of these is seen on the right side below.  However that would be hard to adapt that to the 5mm stepper motor shafts!


Some of the other problems I have faced so far include:

The stepper motors came with gears on them.  I used a gear puller to remove the gears.  When I connected the motors up to the lead screws I discovered that their shafts were bent so much that the top of the lead screws rotated in about a one inch circle.  I had to get new stepper motors.  When I installed the new stepper motors I discovered that the problem was actually the 5mm to 8mm shaft coupler!  It was drilled so crooked that it causes the lead screw to rotate.

As I said above the holes for the nuts in the X axis ends are .55 inches across and both 8mm and 5/16 nuts spin freely in them.  I might have to make my own "nuts" out of aluminum using a 5/16 tap.   Wow was I really off on that one.  It turns out that the nut holes on the top are .55 inches but the nut holes on the bottom are .51 inches!  So I was just looking at the wrong nut holes.

When I assembled the Y axis carriage and slid it towards the back it returns back to the front on its own!  That is because the rod spacing varies by 1/8 of an inch causing the bearings to bind.  I enlarged the holes on the back side and adjusted it so the platform moves smoothly now.

The 8mm bearings are terrible.  They do not move smoothly and they loose some of their balls every time I remove them from the rods.  I might have to replace them with better ones from another vendor?

Some of the 8mm rods are from printers and scanners.  The one on the right side is a tiny bit bigger than 8mm.  I used emery cloth to take it down a little bit so that the bearings move smoothly.

I used 10mm rods (from scanners) and bearing for the Y axis.  They work so much better than the 8 mm bearings.  However their outside diameter does not fit either 1/2 or 3/4 pipe holders.

The spacing of the z axis guide rods varies by 1/8 of an inch from the top to bottom.  That is a tricky measurement since there are rod holders at the top and a home made motor mount at the bottom.  I will have to move the rod holders in about 1/16 of an inch on each side to fix the problem.

While testing the Y axis I realized that the gantry is at the wrong position.  When I move the Y carriage back the print head will not reach the front edge.  I had to unbolt the gantry and move it forward one inch to resolve the problem.  It was six inches from the back edge but it is now 7 inches from the back edge.

The Y axis bearing holders hits the stepper motor that is mounted under it.  That is because I mounted the stepper motor all the way to the right.  It needs to be moved at least an inch to the left. It also needs to be moved so that the wires to the Y platform can be run in the center, the drive belt is there currently.

I cannot put nuts on the Y axis hot plate screws.  The bearing holders are too close to the front and back edge of the Y platform so there is not enough room to put the nuts on the hot plate screws.  I will have to move the Y axis bearing holders 1/4 inch further from the front and back edges.

I tried to mount the Arduino Mega, but like all Arduino's the mounting holes are an afterthought.  I wanted to have screws come through the plastic, then a nut, an insulator then through the Arduino then a last nut.  However the nuts cannot be on that side.  I am trying to rework it to use the standoff's that are used for ports on a PC.

Tuesday, July 29, 2014

I upgraded my CNC with a router for my book "Inexpensive CNC Projects".

I have added a router to my homemade CNC machine.  It used to smoke at a feed rate over 20% with the Dremel.  Now with the router it can cut at 100% and the cuts are much smoother.

It can also cut right through the board.  I changed the feed rate while the Z axis was moving and caused it to crash, almost cutting through the board.  That is visible in the bottom left side of the "N".
Here is the video, it was taken after the crash.
http://youtu.be/k2YVhZnzZ2k



I am also upgrading it to an aluminum frame, this makes the machine more solid than Plexiglas.

This CNC machine can be built with my plans found in my latest book "inexpensive CNC Projects".

Monday, July 21, 2014

My latest book "Inexpensive CNC Projects" and a trip to Florida

I just returned from a quick trip to Florida.  I drove for over 3,000 miles in only eight days!  I went to visit my dad and to give him a copy of my latest book "Inexpensive CNC Projects".  It is dedicated to him because he was a CNC programmer at Ingersol Rand for many years.

Here is a picture of me giving him the book at the nursing home.

We also stopped at the creation museum on the way home.  I was studying the skeletons of the dinosaurs and how they were animated to get ideas for making my next project - a life sized robo raptor!

Here I am next to an animated raptor.

Here is a picture of a raptor skeleton.

Monday, June 23, 2014

One Crazy Virus claimed to be from the "Metropolitan British Police"

Someone showed me a computer this weekend with a virus that I could not even beat in safe mode.  All I could do was to re-install Windows.  The best I could do was to get the task bar to pop up for a split second.  In safe mode the computer just restarts into regular mode and went back to this screen.
 I had to use a camera to take a picture of it.

Another problem is that Malwayre-Bytes anti Malware (MBAM) no longer offers a thorough search and even once I re-installed windows it did not detect the virus as it was in "Old Windows".  Then there is Microsoft security essentials that will not do a scan unless you are connected to the Internet to do an update.....