I can print them for you. Post which files you need.
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Nice job on the load switch! What’s the expected current surge? I see you spec a 150W resistor for it, so 3A at 50V? Does it get hot?
@grejen711 parts are ready for you.
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Thanks! The expected surge is quite high but it’s just a quick spike. The resistor will get warm if you hold the precharge on for several seconds but it only needs to be held for a second. Sorry, I don’t remember the actual calculations but I do know it protects the switch really well.
Awesome. Thank you very much. Will PM details.
Mounting the speed controllers
Cable ties and a foam pad under each one. The pad is cut from the motor packaging. Thinking I might cut that large strap of and go with a second small one through the mounting holes at the other end. Would look tidier.
Wireing harness
Bought some ring connectors and lit up the soldering torch. First pair is a bit toasted.
By the time I finished they were looking pretty. Strip, flux, insert, crimp, heat, feed in solder.
Mocked up one side. All the ESC wires were cut to the same length. Battery cables are waiting for actual batteries before I trim to length and solder on the plugs.
The bolt for the negative side is almost ideal. Just a tad short. Found a better one in my bolt bin. Need two though.
Shorted myself a few connectors so have not yet made crossover connectors. Left side waiting for a switch.
Everything will get taken apart and cleaned up with sandpaper before final connection.
Any suggestions for insulating and mounting the DC 2 DC converter/supply for the main board? Does it get hot? Can I just encase it in that foam rubber and strap it to something?
Perfect. I was over thinking it.
Back at it for an evening. Recieved a spark arrestor knob. Thank you very much @maymayday
First step, disassemble the provided switch. Four screws on the back. One more holding the red knob from the inside. Four major parts plus a spring. Do not loose that spring!
Next, spend an hour digging through my junk to find a scrap of solid core wire. Came up empty so just used some well sized stranded. Strip at least three cm.
Yeah that wire has to go out the other way. Drilled out a thin layer of plastic left from the print. Stuffed the wire through. Both wires installed.
Assembled. Added got glue to stabilize the wires and hold them in place. I also used a drill bit in my fingers to clear out the holes for the spring to save some frustration there.
Tested it with a multimeter. Reassembled the switch with my new knob. Hmmmm what’s wrong with this situation. Doh!
Disassembled switch again, reassembled with the mounting plate in place.
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I ordered the second switch from banggood. Cheaped out on shipping. 
. Man I hope that ETA is a conservative estimate.
Btw that spark arrestor switch knob fits amazingly, perfectly, precisely.
Also, got a track on my Bonkas. They should be in Sumas next week for me to pick up. Seems I may be waiting for a $6 switch, the weather, and busy renovating a rental property, or all three. Sigh…
The #2 switch arrived in half the time expected. Mounted it last night. It is manufactured slightly larger than the one shipped with the OpenPPG. Looks like Paul and Zack shave them down to fit.
So, some time with a sharp knife and and sand paper…
The larger, M5?, bolts thread themselves into the switch plastic perfectly. I drilled out two of the holes in the mounting plate for them. The heads are just a hair’s breadth wide but should be ok. Maybe I’ll pocket the surface of the plates for clearance.
I also now have batteries. Should be able to get to assembly of the major parts later this week.
The weather is bad here so I’m not getting in a rush.
Added the resistor to the spark arrestor switch. Wasn’t sure how to Mount it until I came up with this idea.
Thought it was pretty neat. Then I connected all the power wires and bolted the motor arms in place. Had to mess around a while thinking about wire routing, switch orientation, etc.
Set the back plate on …
Set a couple batteries in place to figure out Cable routing. This looks right. If it is the switch-battery cables will be very short.
Almost there.
After a couple months doing a renovation of our house I got a day to get back to the build. Spent an inordinate amount of thought around the battery cable routing then decided to just let it hang out the sides.
This looked great until I mounted the goose neck arms. They swing back and down and definitely can pinch the positive cables against the frame. Very bad idea.
So, I walked the dogs and thought some more. Then I took the back plate off and routed the cables out the cable holes. Duh!
I made extensive use of cable ties and the foam the motors came so elegantly packaged in to hold things in place and keep connections covered. Suddenly it’s all together!
Except for props, battery mounting, and the harness it’s ready.
Oh yeah. This one tube end gave me some fits until I looked at it.
If you have one that won’t slip on easily it could be dented on the end. I opened it back up with a pair of pliers then checked the rest.
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When I had the battery cables soldered and connected I plugged in a pair of batteries and tried that spark arrestor switch. Worked a treat. Gave it a twist and held it. No crackling noises. Everything just powered up. Snapped the switch on. Everything worked!
Strapped!
Finally got the batteries mounted. After much perusing pictures of bonkas strapped to OpenPPG frames and thinking, over thinking, I ran some 3/4" velcro cable strap through the slots.
Again I used that cool foam the motors came packed in to cushion the batteries against the frame. It also allows a degree of squeeze and provides grip between the batteries and frame. They don’t slide around at all.
Lower battery mounted
Strapping and cushions for center two.
It was… fun running the strapping under the plate to get it through the slots. Top battery mounted.
Final cable routing close up.
Here’re the loops with the batteries out and the cushions aside.
Something I’ve just wondered is how stable that foam will be after some exposure. It’s probably not designed for this and may break down in UV, or even just the air, after some time.
I thought about cutting slots in the foam to run the straps through. Tested a piece and it broke out pretty easily. I’ll probably just double face tape the foam to the plate.
Also note the new digs. Been busy renovating and moving. Still doing the former but I got couple nice kiting sessions in.
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Ready to fly!
Scrutinized the pics linked in the guide for mounting the frame to the harness. Hung the batteries. Installed the props.
Took a picture
or two
And tried it on for size
Started with the center swing arm holes. Will try to do a hang test in the garage. The weight feels very comfortable and not too heavy. Compared to the Blackhawk 125 I’ve flown it seems slightly lighter. I stood with it for about 5 minutes while my wife took a couple dozen pics.
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Also I found some 5/15 high pressure fuel tubing in my junk and cut in some tiny pieces where the battery cables come through the back plate.
…and made some feet for the legs so I can set the thing on the nice floor.
…and some bumpers for the swing arms where they contact the frame.
Just because I was having fun with the stuff.
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Gratulation looks great,
Thank you for shearing your building process.
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