15mm rod system - Spider mount for H4n field recorder

After already creating a special grip for my 3d printed shoulder rig to hold the remove control of the H4n field recorder
it was time to create a proper mounting for the recorder itself.

While using my universal accessory holder of cause works to attach an H4n to a shoulder rig with a common 15mm rod support,
the H4ns internal microphones do pick up vibrations induced by touching things on other parts of the rod system.
The usual way it to mount the microphone in a rubber band spider-mount.
However, even for a very common recorder such as the H4n, no such mount seems to exist for field recorders.
So I designed my own.

Your Thing Has Been Featured

Just a few MINUTES after I posted this design it got featured on Thingiverse!
I'd say the mods are kind of biased to their own (Makerbot) products but I guess it's hard for them not to be.

"As a citizen of Thingiverse, you are receiving this email to keep you updated with activity on your things in the Thingiverse. Your Thing-O-Matic: Removable ABP mod thing has caught the eye of a Thingiverse Admin and it is now being featured! Revel in the glory and check out the other featured things on Thingiverse.com/featured."


Thing-O-Matic: Removable ABP mod

To fully use my old milling toolhead with the new adapter in the Thing-O-Matic,
I need an alternative build-platform.
One that can grip a PCB or something else to be milled.
To do that, there is one issue....
The default Automated-Build-Platform cannot be easily removed without
disassembling all of the platform, taking out the belt and re-tension
everything later when assembling it again.
So here I designed a modification for it, so the ABP can be taken out easily.
You just have to remove 4 bolts and it slides right of.


unattended print

Last night I had my first unattended print with the Thing-O-Matic.
It worked out fine. Ejected the part after cooling down, shut itself down afterwards,...
However I'll still add some more modifications to make it more reliable while I'm not around.
Additional end-stops, a rotary encoder on the extruder (on the filament, not the motor-axis), an IP-camera able to shut down the printer, ...

(The printed part was one of 2 sides for my spider mount to the H4n field audio recorder for my camera shoulder rig)

Dremel Vice

What is it with me and tools...
I just can't go past some decent tools that may be useful to me without extending my workshop. :(

Video: [HOWTO] Building a DSLR shoulder rig - Part I (the basic rig)

I finaly got around to finishing the first longer video for my channel.
Some missing shots I had to improvise with photos and CAD-screenshots.
Lessons learned: record more video on later projects to have enough material for such a video.

Your Thing Has Been Featured

I just got an email that my lens gear has been featured on Thingiverse!


taking apart a camera remote

...just out if curiosity and to see if I could create a switch for my shoulder rig's handle
I took apart a cheap remote that can switch on/of video recording and force an autofocus on my Panasonic cameras.
I was curious how they managed to get the switch to do different things depending on how deep you push it.
...turns out they didn't even used micro-switches but a very, very cheap solution instead.

Thing-O-Matic: cooling the Z-stepper

On the Thing-O-Matic the z-stepper gets very hot.
As the Z-axis does not use a simple threaded rod,
the stepper needs to be kept powered to hold the Z-stage in place.

A while ago tatsuya designed a simple clip that houses a small 40mm DC fan to cool the z-stepper.

As I am moving my TOM quite often, I feared that such a small fan would break off.
So I took a larger fan.
Mine is 40x50mm and very thick.
So I had to re-design this clip anyway.
While at it, I added a number of improvements.
Such as the clip bending and clamping down on the wood instead of sliding on.
Or the clip arms to be shorter, so as not to interfere with the z endstop.
Or the entry to the clip being tapered by 2mm to make it easy to slide on.
Same for the bolt holes that are tapered by 1mm.
And of cause the fan being held by it's front- and back -side and no longer housed inside the clip.

Toolhead adapter for RepMan tools in Thing-O-Matic

I want to experiment with milling PCBs using the new Thing-O-Matic.
I did this in the past on my RepMan but copper-dust was in danger of entering the open electronics, motors and bearings.
The Thing-O-Matic is much more enclosed and clearly separates electronics and motors from the work-volume.

So I looked for existing toolheads that would serve my needs.
Indeen I found some.
However one required to saw apart the freshly printed ataper and re-attach it using hot glue.
(That "somehow" sounds very, very wrong.)
One simple looked like it did not fit the organic shape of the Dremel.
One uses just one arm to hold the Dremel and is thus prone to vibration and flexing.
Two only hold the Dremel via 4 bolts. Kind of like a Christmas-tree stand.
While one of them even requires the use of Makerbeam.

Not the best of options.

However I still have my Dremel-toolhead for the RepMan around.
So I imported the DXF of the RepMan tool-mount into my CAD program and meassured the bolt size and -diameter of the Thing-O-Matics toolhead-mount and found they could be made compatible.

With this adapter, any RepMan toolhead should fit into the TOM.
The allowed tool-diameter is even larger then on the Repman.
However I find the Z-stage of the TOM to be less stable then the construction used in the RepMan.
The long wooden plate is able to flex and deform my multiple millimeters
while the sled used in the Repman is made out of 3 linear bearings compressed between 2 layers of thick acrylics with dozens of bolts in a small and rigid package.
More capable of widthstanding vibration and forces applied to the toolhead.


improving the Thing-O-Matic

Last night I worked myself through the list of Thing-O-Matic improvements.
Some of these changes seem to have already been applied by Makerbot itself.
The first 2 changes I applied myself where

  • a support bracket for the Y idler, as that seems to come loose after a while and some

  • hole plugs, to not get dirt into the electronics. Especially as I later want to build myself another milling-toolhead like I did for my RepMan

First impression of Autodesk 123D beta

The new child of Autodesk.
The Beta can be downloaded for free.

My first impression:

* terms and conditions exist in 4 dozen languages but German is missing
* program is a Beta
* program only exists in US-english
* all the points in "Learn About 123D" do not work on a 64bit Windows (they try to open an swf as a file and the Adobe web-site says that the flash player 10.x is no available in 64 bit.)
* lines in sketches are hidden in "draw"
* sketches can be on flat surfaces but not on non-flat ones
* If the model is in metric units, you cannot specify inches for features (e.g. a 1/4 hole to attach a camera in a metric part)
* the only constraint I have found is "pin down" = lock feature
* I cannot find the operations I did in the model-hierarchy or any kind of construction-timeline
* I also cannot find a way to temporarily supress and operation, only parts
* I can enter basic formulas but not variable-names

It seems to be some kind of "Sketchup meets ProE".
Give extremely visual oriented people very basic parametric tools without allowing much in terms of later modification of the created object.
Useful for simple modifications to solid models in the usual CAD-formats and simple 1-off parts.
Not so much for complex parts that you test-print and then modify earlier steps in the construction history or change any parameters at all.




building a mobile workbench

I travel a lot
and I don't like it, that I have no access to my most often used tools on the road.
So this weekend I build myself a case that can house my new Thing-O-Matic 3d printer, a box with the Dremel Stylus and other small tools, nuts, bolts and other parts, 6 power sockets (you are always short of them), basic camera- and sound- equipment.
The 3d printer is encased in a fabric lined wooden crate that is both stable enough to survive frequent traveling and just lightweight enough so I survive this too. ;)



3d printed geared follow-focus

After my gearless follow focus and with another Thingiverse -user rendering some special gears for me,
I constructed my own lens-gears for use with a (yet to be designed) geared follow focus.

With a geared design I can gear down the hand-wheel for better control (not sure if that is a good thing but I'll experiment)
and I no longer need as much pressure between follow focus and lens as with the simple gearless design.

FF Sync mit DolphinHD5-beta1

The Beta1 of DolphinHD 5.0 is now public.
I found a place where they changed something and my plugin crashed as a method being called no longer existed.
A version that catches this error is currently being signed by Dolphin Labs and will be in the market soon.

Good news: DolphinHD 5.0 supports subfolders for bookmarks.
No code-change on my side was required as the API was designed to support this from the very start.
I hope this also solves the old duplicated bookmark -issue. :/

new HDD trouble

I just got 3 new HDDs for my file-server.
I ordered 3 different drives from 2 manufacturers,
so they would not all fail at the same time.
However my Tranquill BBS only detects the WD 3TB drive and doesn't recognize the existence of the 2 Hitachi 3TB drives at all. :/

I hope to not have to send back the Hitachi drives and replace them with WD but to find a way to use them.

For an unknown reason, later both drives where detected. One already had an EFI-partition. I had to delete that one to use pvcreate.


Thing-O-Matic for traveling

One of the main reasons for me to buy a Thing-O-Matic even thou I already have a RepMan capable of printing much larger objects was,
to have a more portable printer that I could take with me.
Now an important test has been mastered.
YES, it does fit into a bag. Easily even.
Using onle 1/3 of the bag I'm thinking of getting a smaller bag
and to then modify it with foam-cutouts for the printer, Dremel stylus, ABS-spool and some minor tools.
Maybe even cutouts for the most essential camera+sound equipment.

* photo album
* Project Page

Thing-O-Matic - mission accomplished

It is done!
My new Thing-O-Matic is happily printing it's first calibration objects.
Right next to my trusty old RepMan.

I left a LOT of comments about missing details, misleading photos, unlabeled parts and other such shortcomming on the talk -pages of the assembly instructions-wiki.
I also recorded every step of the mechanical setup on video. Currently I'm low on disk space but with some new HDDs I should be able to make an assembly-video explaining what the instructions omit.


Assembling a Thing-O-Matic

Finally my new Thing-O-Matic is here.
It will hopefully be a nice addition to my large RepMan.
Assembly has already started.

I found the assembly-instructions from Makerbot to be quite...lacking in details, so I'm recording every step to make a video-howto of the assembly for my YouTube channel.
Of cause I also added all the feedback on what needs to be improved on the talk-pages of the assembly-instruction in the Makerbot wiki.

I also found a few design-flaws with the automated build platform and with the Y-assembly that I want to improve.
(Make the ABP spring-loaded like on the Repman as a safety precaution, allow for a tightening of the belt for easier assembly and countering any wear-out of the belt,...)


repairing a suitcase

Due to my work I'm traveling a lot.
Once I got a huge suitcase but it did not survive the first trip.
They had used a thin tin-tube as an axle.
So I replaced it with a massive M8 one and secured everything with bolts, locking bolts and large washers.
I did not replace the already worn down wheels yet but will do so in the future (and add wheels with ball bearings in the process.).


H4n noise issue solved

I had a lot of noise in every recording made with my Zoom H4n.
Being an audio novice, I was not sure if that was normal for this price range.
After all, I could only notice the noise using good headphones but not with the usual laptop-speakers.

With lots of testing I finally found something by accident.
I notices that the compressor/limiter was set to "Compressor (General)".
A setting I probably did in the very first days.
When I tried to understand all it's features.

I switched the compressor to "off".
Instantly all noise was gone!
Internal microphone, external directional camera microphone and an extremely cheap external lavalier all where crystal clear.

I played around some more and now that the noise was gone I noticed that there was a clearly noticeable 50Hz humming when using the AC-adapter instead of running the H4n on batteries.
Up to now I always had camera and H4n on AC when recording at home because there was no reason to use batteries in my own home.
Update: It seems that the H4n power-supply is not grounded and this causes a 50z humming. A generic power-supply that is grounded is reported to solve this issue.

I hope this finding may help some of the other Zoom H4n users out there with similar noisy recordings.


Freibyte II

Wow....doing some audio takes a LOT more effort then I though it would.
I recorded that Freibyte -part I was asked to do yesterday.
Couldn't use the very good Zoom H4n internal microphones because my hotel room has a lot of echo to it.
The clamp of the Lavalier was missing, so that one rubbed against my clothes and was unusable.
Leaving only the Sennheiser MKE-400. A directional mono-microphone intended as a good replacement for camera-internal microphones in video.

Turned out it was very good at not picking up the echo.
The slightly higher noise-floor compared to the more expensive H4n was easy to reduce using audacity.
But it DID pick up lots of other, unwanted sounds that came from my direction.
Me inhaling between sentences and some noise from my clothes and water in my mouth.
Luckily I spoke loud enough so they are only noticable in the pause between sentences.
It's a lot of work though to manually go through each and every sentence to remove these by hand. :(


Spider mount for H4n field recorder (inner part)

With the H4n attached to my shoulder rig or camera I noticed that it does pick up some impact noise from my hands on the other side of the rig.
(Most of the time it's not noticeable.)

For a microphone you usually counter this with a spider mount.
However such mounts seem to exist only for conventional microphones.
Not for field recorders.
Using the microphone-stand adapter of the H4n was no option as the high center of gravity only allows for stationary mounting of the recorder.

This is only the inner part.
Feel free to design outer parts according to where you mount the recorder to.
I'll do one for my shoulder rig one of these days.
Other options are e.g a mount for the tip of a sound-pole
or directly to a camera to get a small package.

I left access to the headphone-port open. The cable hitting things is not an issue. You need not worry about that.
Same for the access to the speaker on the lower side. So you can play your recording to the speaker/actor without dismounting the H4n.
I did design easy to access holes to reach the recording-level and playback-level. However these features are not included in the STL export.
This is because it makes the thing stronger and I strongly suggest to use
the RC04-remote for the H4n. Touching buttons on the device while recording would, after all, defy the purpose of this mounting.

* see this design on thingiverse
* the photo album of this project
* my notes in my personal wiki


The project that didn't happen

There was a very cheap workbench in the hardware store.
It had been reduced in price twice already.
I thought about getting it and modifying it to fit into my car.
Removable with foldable legs.

a) it didn't quite fit and
b) I decided that to be used just once every two years on the Chaos Computer Club - Camps this wouldn't warrant the effort.
No matter how much fun it would have been to build this.

Tools while traveling

With my ThingOMatic on its way,
I just got myself one of these battery powered Dremel for cheap.
So I can have the 3d printer in a large bag
and a Dremel to clean the printer parts...



I was just asked to do the next Freibyte show.
(A regular show from 2 guys of the CCC Freiburg.)

Checking out the past shows to see,
what I would get myself into,
I found that one of them had posted the preview-version of the introductory-video I did for my YouTube channel to the Freibyte-Site.
Not sure what to do about it.
Would have been nice to be asked about it first.