ks14 project is not dead

Looking through old posts I see i started my ks14 project in 2012. I wasn't excited about the rf module mounting setup back then and have been working towards being able to machine up some real RF cavities (or at least "RF-cavity-like") parts.

At this point in my DIY Mill project and after implementing Yuriy's TouchDRO on it, I think I'm finally ready to do it right.

Here's a 3D model of the part I need to stack 14 of the USB RF Modules together in a single solid block:

ks14 rf cavity dimensions

Here's the USB RF module that will sit in the cutout:

Stacking those cavities up should make a nice package of Wifi radios. I'll make a couple one sided cavities for the top and bottom covers of the stack and connect them all to the RX splitter already detailed in old posts.

I still need to work out how I'm going to wire up the USB, but I'm pretty sure I'll be gutting the USB hubs I had planned to use and wiring them in.

Hopefully this weekend I'll mill out the first cavity, get things adjusted so the module fits nicely and have the ks14 project back on track.

Troubleshooting Tach stability with new VFD addition

I got my VFD added to the non-milling machine. The first thing I noticed was that it worked :)
The second thing I noticed was that my RPM readout was all over the place (800-2200 @1550RPM actual).

After alot of troubleshooting, it turned out to be my cheap "DVE" 12V power supply running the Arduino was entirely the problem. I discovered this after I tried a battery in place of the Arduino power supply.. and then tried another power supply.

Luckily I found it pretty quick but for people having trouble with their DIY tach sensor circuits and readings, keep my experience here in mind.

VFD Addition to My non-Milling Machine

Since I have installed the tachometer on my TouchDRO setup, I have no choice but to convert my non-milling machine to variable RPM with a VFD (and as I found out, a 3-Phase replacement motor).

With the VFD you can get more than just speed control, reversing, jogging, ramping up/down, increased torque at low speed, blah, blah, blah. There are tons of video's and posts all over the internet of DIY projects using VFD's on various machines which taught me what little I know about them.

VFD

The Teco EV Series (similar to older FM50 series)has many examples of DIY usage on Youtube, so it was sort of the natural choice. I did look around and almost bought one of the new Weg CFW100 Series. Both had V/F and "Sensorless Vector" modes, digital inputs etc. but the configuration software looked a little more impressive on the CFW100 line.

In the end I found a good price on the Teco EV model I needed and decided to go for it. I also got the RS232 plugin and I'm hoping the RPM can be set via RS232 in any future CNC setup I do.

Motor

The VFD is designed to control a three phase motor. That's just how they work. There is such a thing as one that controls single phase motors, but they supposedly don't do much beyond speed-control. So I had to find a replacement for the existing single phase 1HP motor.

I found that I wanted an "inverter duty" motor which seems to primarily mean that it has a high temperature Insulation Class rating like "F". At low RPM the fan does not cool as well, so it's running hotter than it would at the rated RPM. There's also some magic done by the VFD to increase low speed torque(among other things) which makes it run hotter.

With the low duty-cycle manual drilling/milling operations I'll be performing I doubt it would heat up much. Although, if I ever get steppers installed and can run CNC operations it could stay on for longer periods.

Anyway, I picked out this Dayton 1HP 3PH motor. I get a large discount and no shipping cost on it so it's pretty much the cheapest 1HP 3PH I could find (other than well worn used ones).


It's all on order now, hopefully it will come in before this weekend.

TouchDRO setup completed

Well it took way way longer than I planned, but I finally completed the setup of Yuriy's awesome TouchDRO software and hardware on my non-milling machine..

Yes, it's a drill press and I know "you can't use a drill press as a mill". I already covered that here.

Bluetooth module working with Custom Android DRO Shield

I posted long ago about a Custom Arduino shield for use with TouchDRO from www.yuristoys.com. I explained how I had preferred to use RS232 wired output, but I had broken out the connections for hooking up a Bluetooth module.

Yuri was kind enough to add a direct USB connection method to his TouchDRO app, and it worked for me with a USB OTG cable and USB-Serial dongle hanging from my Nexus 7. I was pretty happy but I didn't actually have my scales mounted to my machine so this was just all sitting on my desk looking pretty.

Reading Yuriy's posts comments, I saw the light and became convinced that Bluetooth was the way I needed to go. I ordered the Bluetooth module Yuriy used here on Amazon

Custom Arduino Shield for Android DRO Project

Here's a PCB layout for an Arduino shield customized for the iGaging Arduino interface Yuriy designed for his Android DRO project:

AndoridDRO_Shield_v0.1.pcb



It's (only) readable with software from ExpressPCB

 

diy reverse drawbar

End mill holder with my "reverse drawbar" arrangement

A common question on machining forums across the internet is about making a drill press into a milling machine. The consensus answer is "don't try it, don't even ask".

From what I can see, the most common reason not to do it is that there's no drawbar and the side loads put on the endmill do not allow whatever taper is used on the drill press to hold well enough. Eventually the chuck or whatever holder you have will fly out of the spindle.

The second most common reason I see is that the drill press is not beefy enough to provide a stable platform.

Read on for my version of the infamous "drill press mill".

back in action

Ok, haven't posted in forever. Been busy working or wasting time of course.

I've been stopped on the ks14 project since I decided to scrap the current RF shielding monstrosity and actually mill out a sleek and elegant aluminum block for mounting the PCBs from the USB wifi sticks.

The hope is that the new RF shielding block gives me enough room inside the clipboard box to mount a Sheeva plug computer (Seagate Dockstar), and make this whole thing into a self contained contraption with single gigabit connection to the outside world.

Aluminum stock for RF Shielding blocks

I've got a DIY milling setup I'm almost done with which I plan to use to mill the aluminum material above.

I've pushed a drill press into milling service. But, it's a massive drill press, and I did come up with the equivalent of a drawbar for it. It's only a stainless 8-32 bolt doing the "drawing" into a #3 Morse taper, but it seems good enough for the  light milling I've done so far. I have another post ready which will detail that reverse drawbar thing.

Right now I'm working on mounting some chinese DRO scales(ebay $35) to the X-Y table so I can more easily work with it and compensate for backlash etc.

Cheap $35 single axis DRO scale

I've got a slew of endmills, taps and machining accessories, plus I watched a couple dozen youtube videos, so what can go wrong?!?

I hope to be post another update this weekend with some progress, at least with the DRO scales mounted and the beginnings of some cuts on the RF shielding blocks.