2014-03-27

Accidentally deleted FreeCAD development VM :(

I just accidentally deleted my FreeCAD development VM. :/
Now I need to download my empty VM again, checkout my own GitHub repository, add the upstreams of the other developers, the main upstream and then continue developing.

2014-03-25

Blackmagic Pocket Cinema Camera 25fps endurance test

Setup

25fps, 180° shutter, ISO800
2x Sandisk Extreme Pro 64GB
USRobotics dual UHS-1 USB card reader
iMac
manual lens, drawing no power for autofocus or optical stabilisation.
focus peaking ON

Test 1 raw

  20min 3 seconds of raw footage.

Test 2 raw

BMPCC stops at 19min45sec with 48% battery having filled up the 64GB card.
However it starts blinking a "card full" message after about 15min of recording.
29649 frames
Resolve reports just: 19min 45sec
40minutes to transfer footage to iMac
 => you can't run on 2 cards, dumping one while the other is being recorded to.
59.538.769.788 Byte (59,59 GB on disk)
29.649 frames
3min 33sec to erase all files on the SD-card

With the remaining 48% battery
19 minutes 45 seconds (exactly like before down to the second) onto another SD card.
After 15min 11 seconds the "card full" message starts to blink.
2% battery left
transfer to PC: 42min
59.370.355.068 Byte (59,44 GB on disk)
29.594 frames
Resolve reports: 19min 43sec


With remaining 2% battery left, the camera nearly instantly shuts down in an attempts to record some more.

Test 3 ProRes

39min 43 seconds of ProRes before the battery and not the SD-card ran out.
There was enough space for another 4minutes 52 seconds

2014-03-23

CNC6040 upgrade

I finally found the time to finish the upgrade of my large YOOCNC 6040 from the USB control board (that was already a huge improvement and now works in my smaller TravelCNC) to the russian PLCM-E3 and it's huge breakout board PLCM-B1.

The 4 existing axis all work fine now, both E-Stops (on control box and on the machine) work as does the tool-height-probe input and I have the ability to upgrade to 5 (and even 6) axis later.
I actually want to do that when my "SimpleMultiAxisCAM" is finished.

The dozens of inputs and the 6x 250V 6A relays are not used yet.
I'll connect the 2 E-Stop buttons and the Probe input later.
The relays will probably be used to control the water pump for the spindle cooling water and the compressor for my existing mist-cooling for metal working.

6 axis,
15 inputs,
16 outputs,
6x 250V 6A relays,
controlled via Ethernet and with proper optocouplers and galvanic isolation.
I'll not use the PWM feature as my spindle is controlled via RS485.
28 leds for all axis and inputs can e wired to the front of the enclorure.
...what an upgrade.
BTW: That breakout board is HUGE.

I also found the reson for the "stuck axis" and the "connection lost" issues.
The stuck axis seems to be a fault in the chinese MACH3 remote control and the "connection lost" a faulty USB keyboard that detaches and reattaches from USB and messes up the system for half a second each time.






2014-03-18

Makibox Hotend and power improvements - Version 2

This is my second attempt to fix the issues of the Makibox hotend.
This time In added a number of large and small M4 washers and placed my fan deeper.

Also: Powering the fan and Raspberry Pi from the same 12V supply seems to cause random crashes of the Makibox firmware. Particularly when it's supposed to start heating the hotend. I have gone back to powering the Raspberry Pi via a second power supply and am observing the situation to confirm this as the cause.
Result: It still crashes. Something else must be at fault. Searching...



Results:
The washers are perfectly cool.
The PID control has a hard time reaching target-temperature and usually stays 5°C below what the hot-end should be at. I will need to change the PID settings or block air flow from cooling the hot zone instead of just the washers and shaft.
The bed needed to be leveled again because the length of the hot-end changed a bit.

The TEST PRINT FAILED AGAIN with the same filament stalls as all the others.
At the time of failing the washers where perfectly cool.

Second attempt:
I changed the target temperature to 218°C.
This is a temperature that worked well before and has less mechanical resistance because of lower viscosity.

FAILED


Third attempt:
I changed the target temperature to 190°C.

FAILED

2014-03-17

Makibox Hotend and power improvements

After switching to the AirTripper V3 BSP extruder, I wanted to improve the hotend to finally get reliable printing...

But the first thing that happened was, that the BSP connector of my extruder ...fell out.
I did add a small heat sink and a 12V fan to the top of the hotend.
Since I cannot prevent heat from creeping up from the hot zone to the parts of the hotend that are supposed to stay cool. the intention is to cool the upper parts and dissipate as much of that heat as possible.


While connecting the 12V for the fan, I also connected power for the camera-equipped Raspberry Pi that lives inside the Makibox.
Beware that you need a gas powered or very strong electric soldering iron to solder anything to this PCB. It dissipates all the heat you put into it before the solder has any chance to melt.



test:
I'm currently testing the setup.
The hotend is staying at 235°C for an hour and I'm touching the upper part to feel for any warmth every now and then.
I already know that the "L" shaped heat spreader does get warm to the touch during long running print jobs before friction due to expanding filament above the hot zone ruins the print as even the strongest extruder cannot push hard enough to overcome this.
results:
The "L" shape stays cool while the threaded part and the M4 nut at the top of the threaded part of the Makibox hotend is too hot to touch.
The TEST PRINT FAILED AGAIN with the same filament stalls as all the others.
Either this isn't the issue at all or I need a way to cool the threaded filament tube above the hot zone.


>>> Part II

2014-03-16

Weekend update

Just a quick update on what happened recently.

large CNC:
I'm still waiting for my PLCM-B1 Breakout-Board to fix some electrical noise issues due to not having opto-couplers at the moment.

TravelCNC:
I'm bringing some wires and small parts to change the wiring to use new stepper drivers.
The original, chinese ones where rated far above what they could survive. (advertised as 50V, used at 48V, rated at 45V absolute maximum)

Blackmagic Pocket camera:
I got my Pocket Speed  Booster (0.58x, +1,33 stops) and 50mm f1.4 as well as 30mm f1.4 lenses.
I did find a used Sigma 18-35mm F1,8 DC HSM but it was no longer for sale a day after.
I'll soon make a comparison of
50mm f1.4 +SB
30mm f1.4 + SB
25mm f0.95 Voightländer
17.5mm f0.95 Voightländer
25mm f1.4 Leica
12-35 f2.8 Panasonic
CCTV f1.4 C-mount lenses for 2/3" sensors

4 axis CAM for FreeCAD:
I'm stuck. My plugin compiles but there's no .so file being generated.
Aparently I don't understand enough about cmake.

Makibox A6 HT:
I'm bringing some parts to add a passiv cooler and a cooling fan to the cool part of the hotend.
After exchanging the extruder this seems to be the root cause.

2014-03-03

Using an AirTripper extruder on the Makibox A6

     Because of frequent filament stalls on my Makibox A6 HT, I'm currently upgrading to a different hotend that (hopefully) can transfer more force onto the filament. That should allow it to overcome added resistance in the hotend due to heating and thus expanding filament. That in turn would make the printer more reliable.
     
    Problem 1
    The stock drive gear is 9.5mm away from where the filament would be with the Aitripper V3.
Solution: Get an MK7 Drive Gear Pulley (for 1.75mm filament).
It came out the best for this purpose in a nice test.
Don't install the MK7 just yet! Read to the end first!



    Problem 2 
    The BSP Air Tripper has a thinner bowden tube.
Solution: Cut an M4 thread into the end of the tube, place an M4 nut on it.
Now it will be compatible with the Makibox hot-end.

     

    Problem 3

    The shaft is too short to hold the MK7 drive gear in reverse.
    Also the hole in the MK7 is tappered, so you cannot even insert the shaft into the other end and need excessive force to push it on the right way.

Obviously spacers of 4.5mm for the stepper motor are needed.
You need to print this space before installing the MK7 because you can't get it off anymore.
You need an allen key of 1.4mm diameter for the grub screw.
Also the long screws need to be 11mm longer (6mm for the acrylic, 5mm for the spacers).
Thus M3x41mm or M3 threaded rod is needed.

Solution: M3 threaded rod, 4x2 M3 nuts as spacer, 4x M3 nut for mounting


Problem 4
Let's mount everything up!
The Makibox has only 3 mounting holes.
The Airtripper only needs 3 bolts.
...different 3 bolts then the ones we have holes for.
Solution: an M4 nut can mount your extruder on top of the Makibox through one of the air cooling slits.

Problem 5
So let's do a dry-run first!
You can't push the filament through.
The exit-hole and the center of the BSP connector are not aligned and the filament hits the wal of it's hole with no way of manual intervention. Force can't overcome this issue.

The photo shows the abolute maximum how far you can insert the filament.
Solution: none yet. You may get it to push through with excessive force and trying serveral dozen times.


Note 6

The new drive gear is larger.  You need to multiply a factor of 0.57 to the amount of filament to transport in your slicer settings.