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Friday, 7 September 2018

Dual Hotends on K8200

Going to see what this looks like on the old K8200 3D Printer a Chimera V6 dual head with remote bowden titans extruders will set it up for 3mm and 1.75mm. I have a feeling I might try some PVA dissolving filament as support material.  

0.2mm,0.3mm, 0.4mm and 0.5mm Nozzles for 1.75mm filament, also have some 1mm and 1.5mm for 3mm filament. Looks like the heaters can be either 12V or 24V and the thermistors are standard 100K NTC glass bead type.

I'll add a pair of silicon J6 clone socks to them as well so can differentiate between them.

The mount will almost certainly be an aluminum plate or 3D printeted backet.

Looks like RAMPS1.4 will happily accommodate the extra extruder and hot end.

The filament run out sensors will also be separate, not sure can have on both but will investigate.

Wednesday, 5 September 2018

Fitted some longer arm microswitches to the Y axis of the PCB CNC

Set a job running, it was all running fine but found the CNC had happily reset it's origin after 1st PCB was milled (8 pcb on the same bit of PCB/FR4), As the shorter armed microswitch had not triggered when it was supposed to. The sacrificial table cover had been milled instead for the next 7. Oops.

So swapped out the Y axis micro switches for some longer arm ones instead.

Think I might look at 3D printer Raspberry Pi and Octoprint / Octolapse type functionality with a small camera so can catch issues. I think there is a Prontoneer Raspberry Pi CNC shield that is basically the same as the Arduino one but you aslo get the Raspberry Pi control.

Tuesday, 28 August 2018

tinkercad to make mi0iou wobbulator enclosure

Not found one (must be one out there somewhere) but going to use tinkercad to design and enclosure for my old raspberry pi A based version.

See for details of the project

The boards approximately:

Will now create an box enclosure and then copy the boards onto it, but as a 'hole' so you get all the openings in the correct place.

Have gauge with me today so will measure those SMA connectors and the pots a bit better.

Saturday, 25 August 2018

shack needs sorted out as had to move stuff to operate as had issue finding space!

Far too much stuff in there so in between qso for GQRP summer sizzler looking at what is in the shack and cleaning up a bit.

Over a years worth of older IT and Radio magazines can go, plus all the older QSL cards, as scanning them now.

Not sure about the piles of buro and clublog card requests where I said electronic only. Might just grab random card, stick on a label and send it back.

Thursday, 23 August 2018


As coming into the winter months again and LF is dominating for a while going to improve the LF options a bit.

I had  used an IRF510 based PA based on with one of G3YXM/G0MRF's  transmitters. I had played with transverters using  10MHz/30m and not the more usual 10m/30MHz. Antenna was an inverted L.

The bench certainly had a Graham VK3XDK 472KHz transverter for KX3  completed but not in an enclosure so I will have to pull it all together again and finish it off.

I note previously I had used 22mm or 25mm, cannot remember which, white PVC conduits as the LPF coil foms. I see there are some nice 3D printed LPF coil forms for 472KHz available so will try to source the STL files and take a look.

Buddipole guy rig

Used my buddipole all over the place and one thing that is a major pain is if it is windy or is tugged over (later happens far too often) it can be a pain. I ofgten just attach the carry bag to the bottom of the tripole and fill it with sand/stones.

Anyway whilst looking for something else I found this: and thought THAT is exactly what I need.

He used BB gun pellets to allow the rotation which are 6mm diameter, pretty sure I have some steel ball bearings with the same diameter and as I cycle I have lots of lithium grease.

And it is of course in the correct colour for qrp.

My own print photos etc will go here:

The 6mm metal ball bearings have cleaned up nicely.
Now to look at that lithium grease.

CNC end stops

Since had a rethink after finding I had some nice (larger) micro switches so will build some locations and wire them in instead.

I see someone did this for their 1610 CNC and the parts are in thingiverse.

This is what I added:

After having fun drilling 2mm holes and using M2.5 hex head screws I did the same for the X stops and mounted the switches.

I set them up so the whole drill assemble when moved on the X axis towards an end stop will trigger it.

The Z switches I need slightly longer arms on the switches, or will have to add something to the bed to switch it. Procrastination time needed. Use slightly longer screws and lock nuts too.

I also added some nice new 8x5 bearing couplers too. The one on the Z axis looks fine for now but might take it apart and replace.