Saturday, 18 February 2017

CNC upgrade progress - Current status

DIY CNC is just another way of saying "work in progress". Work in progress because I make constant improvements when I have a new idea which I believe makes it better in some way. However, my DIY CNC upgrade is now as ready as planned plus some more, and the currently ongoing improvements are smaller and smaller, so it is worth to note the current status.

Materials used

The material used (mainly, but not a complete list) is 45x90 and 30x60 aluminium extruded profiles, 10mm, 12mm and 15mm thick aluminium plates, hundreds of stainless steel screws, T-nuts and bolts mainly in 5, 6 and 8mm diameters. The total weight is approximately 80-90kg, including wiring, motors and all the electronics and power supply.

Increased stability

The actual CNC is desktop size but has its own feet, not just placed on a table. Originally on industrial rubber wheels, these feet are now lowered to some wooden blocks to give maximum possible stability. Earlier it was just standing on four lockable rubber wheels for ease of moving around but the drawback is that this is only good as far as low speed and acceleration is used. At higher speed and acceleration the whole machine was shaking, even when those wheels were locked, and this cause some accuracy and vibration problems, so I decided to lower the machine on four wooden blocks, making it more stable and less prone to shaking. The rubber wheels are still there but to roll around the machine on them is now a bit more complicated because it must be lifted first to remove the blocks and lowered down to the wheels before it can be rolled. This solution is better and actually necessary due to the fact that the acceleration values I have now are much higher than before.

Speed and acceleration

The maximum values I can get now is 10,000mm/min speed and 900mm/s/s acceleration. On my fairly small machine I found this crazy and scary fast, so I backed off a bit and set the X and Y to only 9,000mm/min, the Z to 7,000mm/min speed and all three to700mm/s2 acceleration.

Short technical summary

  • Footprint (total area it is occupying in the room): 750 x 650mm
  • Table height from floor: 890mm
  • Y table size: 450 x 300mm
  • Weight of Y: 17,5kg
  • Working area: 310 x 270mm
  • Weight of X-beam: 13,7kg
  • Size of the X-beam (height x width): 500 x 540mm
  • Size of Z: 350 x 150 mm
  • Weight of Z: 8.5kg (this is increased due to a different, longer and thicker Z plate I use now)
  • Z clearance from table top: 160mm
  • Maximum speed: X and Y = 9,000mm/min, Z = 7,000mm/min
  • Maximum acceleration: 700mm/s2
  • Stepper motor data: NEMA23 2.7V/phase, 3A, 1.6uh, 0.9 Ohm/phase
  • Stepper motor driver: DQ542MA
  • Stepper drivers PSU: 44VDC unregulated supply, based on a toroidal transformer
  • Motion controller: UC300ETH
  • Spindle motor: 24,000 RPM 65mm diameter air cooled 1.5kW spindle
  • Spindle motor power supply: Bosch Rexroth EFC 5610 VFD
  • Spindle RPM control via Modbus communication
  • CNC software:  UCCNC from CNC Drive (a Hungarian company)

A never ending story

It was a long journey to get where I am now, but it was a very interesting and challenging one. Have a look on the right side, scroll down to "My CNC story" section to know more about it. The links in that section are pointing to previous posts about the progress, all the way from just a pile of aluminium to now with a fully functional nice machine, with both failures and successes documented and photographed. You will find not only textual information, but also many images and video films showing the machine in different stages and details.

However, this is not the end, since for me, DIY CNC means continuous changes and improvements so it is a never ending story, which will last as long as I find this hobby interesting.

Future improvement plans and other activities

This is just a short list of what I have in mind or working on for the moment. The progress is good, but I will not give out any details yet. Also, priorities may change as time goes by.


This is my own invention, or innovative solution if you want to call it that. It is a generic flash adapter for Nikon 1 V series cameras, allowing the camera to use standard flashes or radio triggers made for DSLR cameras. The very popular current version is called V2-F1A and of course the next one will be called V3-F1A or something similar. If you are interested in details, have a look on my blog. There are many posts about it. This innovative adapter was actually what started my DIY CNC project activity originally.

Anyway, follow this link for more details about this adapter:

Adding a 3D printer head

This is an idea I have but it is still early to say much about it. In my opinion it should be fairly easy to do it. My machine is now fast enough for the task but I have to look at it deeper. In any case, the Z is designed so that the spindle motor can easily be removed and replaced by a 3D printer head, or if I decide to do so, I could add the printer head by attaching it to the left side or the front of the spindle bracket, where I have a few drilled and tapped for optional accessory.

A high speed probe

Have all the macros written for this but need to develop the hardware and make a working prototype. I know how to do it and the work is started and the progress is good, but it is a parallel process and there are other things which pushed back the priority.

Shutter lag tester

This is a project connected to photography, not much to do with my DIY CNC except that like the V2-F1A adapter, my DIY CNC machine will be used for making it. I have a working prototype since several years which I have been using successfully but now it is time to make a commercial product out of it. This product is of interest for people and companies who technically test and validate cameras of different brand, either just out of interest or as a professional work. It measures the shutter lag with very high accuracy.

A new Z axis

In my opinion the Z can never be too good. I am happy with it right now, but I have several ideas about how to improve it even more. Never the less, it is very nice in my opinion and works well as it is.

A new X axis

This goes perhaps hand in hand with the Z axis. Maybe this is more important than the Z improvement. I think that if I can increase the rigidity of my X axis even more than my machine will be even more accurate and better, faster.

Replacing the steppers with servos

This is probably far off in the future, but would be fun to do it. I think that this change needs not only a simple replacement of necessary motors and drivers, but also improvement of the whole machine structure. I would be very disappointed if the huge increase in acceleration and speed could not be used fully because of structural issues, so the mass and the rigidity of the base, as well as the X beam, must go through a major upgrade before I invest in servo motors, but it is on my list of possible future improvements.

That's enough for now

I guess that the above, plus some other small things, will fill all my time for some years ahead. After all, this is just a hobby for me, and along with other hobbies and interests as well as a full time job and a family, it is enough for now.

Tuesday, 7 February 2017

The protective diode inside the V2-F1A

There is a protective diode inside the V2-F1A flash adapter. It's task is to protect the camera in case a user tries to attach a flash with high trigger voltage.

Can this diode cause a problem? Yes, in theory it can, but in reality it is very unlikely. Each individual adapter is made and assembled by myself. They are tested also by myself several times during the process of making and assembling, before they end up in the envelop for shipping.

Reversed diode

If the diode would be installed reversed because of a mistake then the tests would fail and no flash would be triggered on my desk, so the probability that a diode is reversed in a delivered adapter is zero, no question about that.

Broken diode

If the adapter would be exposed to extreme force so that the diode breaks than the adapter is crashed totally and it would be obvious that the adapter is useless in this case.

Bad soldering

If the soldering would for some reason loosen then the diode would get disconnected. In this case, the protection is no longer active as protection, but the adapter would work just fine, as long as the user is not connecting  a flash with high trigger voltage. If a flash with high trigger voltage would be connected to the adapter then the camera could get damaged without the diode, but a normal flash, made for digital cameras, would still work.

Damaged diode due to high voltage flash

If the diode is fully functional and a user would connect a flash with high trigger voltage than the diode would protect the camera from getting damaged but the flash would not fire. There is a slight possibility that the diode would get damaged in this case, even if my experience shows otherwise. When I experimented with the diode and a high voltage flash it never got damaged.

These experiments are documented on my blog in this post:

Note that I do not test each adapter with a high voltage flash because of the obvious risks of causing damage to the adapter or the flash. The above tests were only made as an experiment because another customer have reported problems, which later on turned out to be caused by the fact that he tried to use a flash which was a high trigger voltage flash.

Diode with unknown damage

In theory there is a possibility that a diode gets damaged at one stage, even if this is not likely.

It is easy to test the presence and the condition of the diode. Anyone with some very basic electronic knowledge and a simple multi-meter instrument with a diode measuring option can verify the diode is working or not.

Touch the outer (GND) part of the hot shoe with the positive lead and the centre contact with the negative (common or GND can also be called) lead, like shown in the picture to the left.

Check and verify that the voltage displayed by the instrument is about 0.7V, it can be some more or some less. Switch leads, now touching the hot shoe GND with the negative lead and the centre contact with the positive lead and verify that the display does not show any voltage. It should display infinite, OL or something similar, not 0.0V.

If 0.0V is displayed then there is a short inside the diode and the V2-F1A is no longer working at all. If no voltage is displayed at all during the first measurement then the diode is burned out and the protection is gone. In this case the adapter can still be used and it should work, but the camera is not protected any more against high voltage flash use.

The V2-F1A adapter with YN622N remote flash triggers

For more details about the V2-F1A flash adapter for the Nikon 1 V series cameras, please read:

Some background about my radio trigger

Until last week I used some 10 years old radio triggers to trigger external flashes. These are now replaced with a kit, consisting of a Youngnuo YN622N-TX controller unit and two Youngnuo YN622N transceivers. I am planning to buy more transceivers now that I know these work well.

Note that this post is not intended to be a review of these units, just some information that these units work very well, not only on my D800 in iTTL modes, but also on the Nikon 1 V1, V2 and V3, which can use these together with the V2-F1A flash adapter, but of course, only in manual mode, since TTL is not supported by the adapter.

Two major reasons why I bought this kit

One is that my old triggers are far too old and deserves to be replaced. There is not much to write about this reason, other than of course, my new triggers are miles ahead in functionality and build quality, compared with the old $15 triggers I used before. No surprise there, I would be very disappointed otherwise. I will not compare them or discuss all the new functions, just a short summary that with the D800 the triggers in iTTL mode support not only normal TTL, but also high speed (Super FP) mode. Both the YN622N-TX controller and the YN622N transceiver has also built in AF assist LED and this works very well also, as opposed to the AF assist LED in the Nikon original SB-900 I also have. Of course, none of these functions are available if the triggers are used on a Nikon 1 camera because iTTL mode is not supported by the V2-F1A.

The other, even stronger reason why I bought this kit for is that I received a report from one of my customers complaining about the V2-F1A and saying that it is not working on his V3. Fortunately I know now that these work very well with the V2-F1A adapter. Though I still at this moment have no idea why he has some problems, since it seems that the problem is not very high on his priority list, so he is not very active in self help. Never the less, I decided to buy a kit just to make sure I can test it and see the problem for myself if there is one.

The video below shows how to use the V2-F1A and YN622N remote flash triggers on a Nikon 1 V1, V2 or V3 camera.

I am convinced that the problem this user sadly experiences depends on something else, not caused by these triggers or the V2-F1A, but without his assistance I can't solve the problem. The V2-F1A adapter works on the Nikon 1 V3, just as well as on the other two models, this is confirmed by several other Nikon 1 V3 users. The YN622N as said before, works on my camera and since all the other camera models trigger the flash the same way, I have no reason to believe that they would present a problem for the YN622N.

Error description

When I put a flash trigger on the V2-F1A (when on the V3) and make a picture, I see that the remote trigger gets some kind of signal. But it doesn't fire the flash. When I push the test button on the trigger on the V2-F1A, the flash does flash.

There is one condition when the YN622N kit behaves this way. This situation is shown at the 1 minute 20 second mark in the above video. At this time mark I turn off the group and Group A does not have a mode allocated to it after that. When the shutter release button on the camera is pressed the transmitter is triggered, the receivers sense the signal and the LEDs will flash normally but the flash on the triggers are not fired. When any of the Test buttons are pushed the flashes will fire normally.

This is not an error

It is a normal condition. If the user does not select  a mode for a group than that group will not be triggered. The LEDs in the transceivers and the transmitter indicate that something is going on, a trigger signal is sent/received but they also look at the "address" the signals been sent to, and they interpret that the trigger was not meant to be sent to their flash, so they don't fire the flash.

The solution

Normally it is enough to select the right mode for that group again and the flash will fire. If the units end up in an unknown state it is best to reset to factory default condition. All groups are set to TTL and everything ends up in channel 1 as default. In this condition the controller will send the signal to all transceivers and they will trigger the flashes and everything should be fine after that.

Please read the manual

This can not be emphasized enough. Unfortunately it seems that we live in a world with more and more complicated equipment but less and less interest for reading manuals and understanding the equipment we spend money on buying.

It is very important to know the equipment we use, which is why I try to convince everybody to read the manual, and which is why I include a short manual with every adapter. This is the case, not just for the adapter, but also for everything connected to it. Though it is not always easy to understand every manual, it is important to understand every equipment. It is in the best interest of each user of any equipment, otherwise the equipment can be damaged, or in some cases even personal injury can occur. Some manuals are longer than others, some are harder to understand than others, but never the less, that is where most information is gathered and that is where we can learn the basics about the equipment we use. Some parts of a manual are more important than others, but there is a reason for why the writer spent time in writing.

Important points in the manual of V2-F1A

  • Always read the manual of the equipment before use.
  • Always attach the flash or the trigger to the adapter first, before pushing the adapter in the camera hot shoe.
  • Always attach a heavy flash via a PC cord.
  • Never put anything heavy in the V2-F1A hot shoe.
  • Never exceed the maximum weight of 120 g (4.2 oz) in the hot shoe, including batteries
  • Never use a high voltage flash.
  • Always attach the PC cord before pushing the adapter in the camera hot shoe if a PC cord is used.
  • Always handle the adapter with care, especially the contact which is used for triggering is very delicate. Nothing I can help, since the original Nikon design does not allow stronger, more robust contact. 
Not following the above may result in damage of the adapter, the flash, the trigger, the camera or any other equipment connected to it.


The Youngnuo YN622N-TX controller unit and the Youngnuo YN622N transceivers are very nice pair. Easy to set up, very reliable in use and the only thing to watch out for is that the right group must be set up on both the transmitter (the controller) and the receivers (also called transceivers), and that there are fresh batteries in all the units.

A few words about batteries

I no longer use rechargeable batteries because they all, regardless of brand, cause trouble sooner or later. Also, they have lower voltage, and actually not suitable for equipment which consumes low current, like these remote triggers. They can also discharge without warning and the self discharging is always a problem. This is not the case with ordinary high quality alkaline batteries, and my advice is always to use alkaline batteries, especially in remote controllers or other low current consumer products. Personally I prefer always to use alkaline, even in the flash guns.