Machining mmWave Radar Rotary Couplers at 122 GHz

[@older-wiser-better]

Not a clue what you are talking about but this video of yours is just brilliant.

[@MachiningandMicrowaves]

That makes two of us, I have no idea what I'm talking about either, so you are in excellent company!

[@mlekotron]

I know nothing about microwaves but I love your videos!

[@MachiningandMicrowaves]

I only know just enough to be dangerous! I love making them, so that's a double win.

[@vmiguel1988]

You just need to know the right time to not burn the popcorn!

[@MuntyScruntFundle]

A quick note on unusual drills and reamers, I've found ACCU and Shop-Apt really useful. I'm just a bloke in a shed making daft stuff, but they're my go to people when I need something precise. (As well as Cromwell and Cutwel and Trucut and Protool and everyone else!)

[@MachiningandMicrowaves]

I use Cutwel, Rotogrip, Accu, Cromwell, MSC and some of the cheapies, but for stuff that I really need to perform, I tend to to to Drill Service of Horley. Cutwel are great for tech support and do a good range of the esoteric stuff from Simtek, plus left/right-handed parting tools and suchlike. I wait for special offers from Cutwel for inserts etc, and sometime take advantage of their "get a free tool if you but 10/20 inserts" deals. Also use Arceurotrade, RDGTools, Chronos, Linear Tools and several others. I had some stuff from Shop-APT a couple of weeks back, they had some good pricing on what I needed. Drill Service do a custom tooling service for really odd tools, and will make up reamers and drills to odd dimensions.

[@PRDRF]

Impressive job, Neil! Greetings from the mmwave design engineer. We work with similar waveguide structures at 100 GHz and above. Your content is definitely a gem for us.

[@bottlekruiser]

Nothing to go with a cup of tea like some microwave waveguie machining microwaveguide, if you will

[@astralchemistry8732]

Neither did I understand the problem nor the solution but I enjoyed the machining and the jokes! :D

[@CaptainKirk01]

I love your channel. Your way over my head with what your making. I understand some of the electronics concepts, just not the application, I would like some direction to understand how this stuff is actually used? a link or two? Is this the black arts? Are you doing mysterious things with microwaves? I want to know.....we all know what happens in a microwave resonance cascade - the lasagna explodes.

[@MachiningandMicrowaves]

I've just bought a new Sony alpha-7 IV with a stabilizing gimbal so that I can take some decent footage of some of these systems in use, but I still have about four months of machining orders to clear before I can start doing some vids about practical applications. I'll get there eventually!

[@neffk]

You want a solid carbide hole-starting drill, not a center or "stub drill"

[@MachiningandMicrowaves]

Agreed. I tried it initially with a 6mm carbide spotting drill, but it didn't centre the long-series drill properly. Under the microscope I could see why. The long slow-taper drill has a flatter point than the spotting drill and it was catching on one side of the spotted hole, which was a little over 2mm across. Using a centre drill is not a good solution for this, I agree. I bought some 3mm carbide spotting drills and now use those for starting these holes, but then use a carbide 1.8 mm stub drill for the first 8-10 mm of the hole and then finally hit it with the 1.90 mm slow-spiral drill and then the reamer. That seems to give the best results overall, alt least in brass,. The similar parts I make in Tellurium Copper need a lot more care, but the process is similar, and with the tiny spotting drill (and a non-bent 1.90 long-series drill) and 3 mm pecks, I've not had any problems with concentricity or finish. Yet.

[@stargazer7644]

I only watch for the "Weeeeeeeeee!"

[@markhodgson2348]

Silver plated?

[@MachiningandMicrowaves]

Plating the 2mm core guide is tough, it's easier to press in a silver rod or tube and ream it, but then it's a pain to get the connection to plating at the face. Brass is definitely not ideal, but the loss is low enough not to matter much for the specific application of linking the radar chips to testgear. It's reasonably easy to make the cores from Tellurium Copper, but then you have to deal with tarnish or face the problem of internal plating. I'm trying out brush plating with gold (using Potassium dicyanoaurate) and pulling a felted wire through the core as a simple protective layer, but getting a thick enough layer to be conductive down to six skin depths at 122 GHz is hard. Also I have to deal with migration of the copper into the gold. Huge fun

[@edgeeffect]

I've had a double helping of nice spiral chips off of brass this week... but Stefan's don't go "weeeeee"!

[@MachiningandMicrowaves]

I think you need a "special" microphone to pick that up....

[@rallymax2]

A comment. All hail the algorithm.

[@derkarhu5079]

Just wondering if you could have used a differential thread mechanism for the adjustment part, say 1 mm and .75 mm pitch, for 0.25mm per revolution of the adjustment collar.... signed: just an amateur

[@MachiningandMicrowaves]

The in-out adjustment isn't totally critical, so the 0.5 mm pitch 8mm thread is good enough for this application. There are times that it makes a lot of sense to use differential threads, and I might have some of those in an upcoming video were I need an extremely fine adjustment. There's a good case for using some very closely-matched imperial and metric threads like a 1mm metric pitch and 24 TPI imperial to generate an effective 51 micrometres per turn (~500 tpi).

[@derkarhu5079]

Thanks for your hi Q answer ! I'll keep an eye out, in any case, usually some interesting goings-on at your place :-)

[@foxbat888]

Amazing precision, 122Ghz will not tolerate even small imperfections, very enjoyable just watching how you make these parts

[@MachiningandMicrowaves]

Soon I need to make some parts for 248GHz. This is going to be a whole new level of "fun"!

[@BuildBreakFix]

Yup only microwaves i know about are ones make my food as I drink with a beer! yet still interesting video!

[@MachiningandMicrowaves]

Same sort of microwaves as in a cooker except the wavelength is about 1/20th the size and the power is about a millionth as much as an oven. No use for making dinner but we can use it for a radio link around 60 miles/100km long.

[@campbellmorrison8540]

Impressive, Im surprised you got away with turning that flange on such a thin stem in the collet. Nothing like sharp tooling huh :)

[@MachiningandMicrowaves]

I seem to have got away with it on 14 of those parts. I did get a little chatter on one, but when I flipped the insert to the unused edge, it was fine again. Those inserts do wear fairly fast on brass, but in terms of cost per part, it's negligible. I use an ester-based cutting oil for finish cuts on brass to reduce tool pressure a little and help with chip clearance. I do get some adverse comments about that, but on long thin parts where I'm looking at precise dimensions and fine surface finishes, it does seem to make a small improvement. I would like to make a proper custom collet, but as the entire worldwide demand is probably 30 units, it's probably not worth it. In the section where I'm cutting the counterbores on the mill, I did notice that the chips on the surface of the flange started to move with chatter in one of the holes, but that was the only time. A proper custom fixture would prevent that

[@AlessioSangalli]

@@MachiningandMicrowaves where did you learn about the properties of lubricants in regards to tool pressure etc?

[@MachiningandMicrowaves]

I was talking to a technical adviser at one of my suppliers and he mentioned that one of their clients found a small improvement on fine cuts with aluminium inserts on brass precision parts when they used an oil drip. I thought I'd give it a try to see if the effect was significant. Not sure it is measurably better, but I'm hitting dimensions very reliably with fine balanced cuts. It might be psychological, so I should do some identical parts with and without and see if the dimensions and surface finish are really any different. This is all on CZ121, it's possible the were using Naval Brass or something more exotic or with more lead or something. I need the parts to be gold-plated, so I need to avoid too much lead content.

[@AlessioSangalli]

@@MachiningandMicrowaves do you compensate your dimensions to allow for the gold plating? Also, even if it's only psychological, it's good, it does not hurt to have some magic recipes 😅

[@campbellmorrison8540]

@@MachiningandMicrowaves You bring up a point I have wondered about for ages, why do these types of parts get gold plated?

[@smallcnclathes]

Entertaining as always. I love the render and lighting effects you get with Fusion, pretty sure my cad can do that, I just don't know how! Nice to see someone else using the inserts for aluminium on brass, works really well. Some folks stay away from narrow parting tools thinking they are too weak. They then have to endure the horrible vibration that a 3mm insert gives them on a small lathe. I noticed the finish you obtained parting off looked acceptable for finished product. Noticed you wiped a taper with cloth or paper towel. I was taught to do a final wipe with a finger as anything left behind you will feel with your finger but not if using a cloth etc.

[@MachiningandMicrowaves]

Good point about the finger, but when I'm filming, I'd have to keep cleaning the offending digit so I don't get oil on the lights and camera, so it's all a bit artificial. Also I chop out about 90% of the footage where I fiddle about and double-check so that I can keep the narrative flow going, so what ends up in the vid is highly selective. Those 1.5 mm parting/grooving tools are HUGE in comparison with those I have from Simtek, which are only 0.5 mm wide. They'll turn up in a future video. The inserts are scarily-expensive, but on tiny aluminium mandrel parts which are going to be (spoiler alert) dissolved in hot caustic after electroforming, they last forever. As for the lighting in Fusion, I just fiddle with the settings until it looks pretty. I have other rendering tools like Blender and POV-ray and visualisation tools like Paraview, but if I can just use Fusion, it saves a pile of time.

[@AlessioSangalli]

@@MachiningandMicrowaves I just finished "tuning" an animation for the astronomy club made in POV-ray, I just love its SDL.

[@MachiningandMicrowaves]

I used to do a lot on POV-ray and Moray and Blender, but I don't use them enough to be fluent

[@WhiskeyDale]

Quinn & Kurtis getting a shout out. nice

[@MachiningandMicrowaves]

Kurtis, Karen and Homie are a major influence.... so is Vice Grip Garage and all the YT precision machinists like Joe, Stefan, Peter, Max and Rob, plus the folks like Breaking Taps, Applied Science, Huygens Optics and other seriously technical channels. Explosions and Fire and Nile Red also, for "different" reasons. I can't get my Chihuahuas (Dido and Daisy) to perform for the camera yet. I must try to get them involved now I have a proper camera (Sony a7 IV + motion gimbal - I feel like a proper photonerd now). I'm trying to get the hang of manim so I can do animated charts like 3b1b

[@neffk]

It would probably be better to relieve the shank of that reamer. Do you have a d-bit grinder?

[@MachiningandMicrowaves]

Now you have got me thinking. I recall when I bought those reamers that they were supposed to have a very slightly reduced shank for maybe 6m beyond the flutes. On the video though, that reamer certainly doesn't *look* like it's been relieved unless it was done for the full length of the shank. I have a horrible feeling that I could have used the wrong 2 mm reamer on that part as I have an older (cheaper) one as well as the two really good ones. I have an Alexander copy of a Deckel D-bit grinder, so it would be simple enough to modify it. First though, I'm going to check my reamers drawer to see if I picked the wrong one and if the "right" one is indeed relieved. Well spotted

[@igorb4650]

Your AI really seems having really bad time lately, wonder why

[@MachiningandMicrowaves]

She's probably just irritated that I'm not making videos fast enough.

[@belatoth3763]

...righto, so we watch similar channels. I'm hardly wait for the time you say: ...allright guys, this could be a wrap, as always, thank you for watching...

[@MachiningandMicrowaves]

Heh heh, it's far too easy to pick up other folks' catchphrases. I'm in real danger of sounding like a certain gent from Vice Grip Garage. Luckily, I can't imagine anyone borrowing my "I think that'll do!"

[@belatoth3763]

@@MachiningandMicrowaves It is more like a crossover in series, viewers love it. Your English and your humour is far more intricate than anyone else's in the machining scene so that is another reason I watch your show.

[@Ashley.0000]

Its good to see you like Kurtis from CEE. He has a banana ruler lol

[@MachiningandMicrowaves]

That banana caliper someone sent him was a masterpiece. Nobody gets to see my out-takes because they are nowhere near as good as Kurtis. I'm trying to train my Chihuahuas to do a Homie impression, but they can't tear the packages open with their tiny delicate teef...

[@quinnmclaughlin7537]

I Suck at math, but I know enough about So many other subjects that your videos are 'brain candy' any more complicated and I'd loose interest, just complicated enough to make me keep watching.

[@Landrew0]

Where can I buy a female insult-bot?

[@MachiningandMicrowaves]

I rather think that they find you, then hunt you down and install themselves invisibly on all your devices. Nowhere to run, nowhere to hide.

[@o0Blackout0o]

Amazing video's, really enjoying them! Do you have a video of this in operation or some measured results of the piece ?

[@peterfitzpatrick7032]

I just want to say that your detailed replies to others here in the comments section are as valuable as the video itself, given the precious time taken, I really appreciate that effort on your part...yer a good egg... 🤗 From the Emerald Isle 😎👍☘️🍺

[@MachiningandMicrowaves]

I often learn a lot when I'm researching replies and get some good new ideas as well, so it's a two-way street.

[@nicholasmcconnell7853]

Like most here, lowly machinist but your videos are a joy. Keep it up!

[@MachiningandMicrowaves]

No such thing as a "lowly" machinist, they are all Gods in my world-view. I'm totally in awe of *proper* machinists who know what they are doing. I'm a hacker, amateur scientist, coder and radio comms/network engineer who earns a daily crust being a cybersecurity architect (whatever THAT means) and messes about in a home shop designing and making shiny things that make me happy. The fact that they also WORK is a huge bonus, and when you add in the nice comments from the KZbin community, it's wonderful and life-enhancing.

[@johnydl]

is that a TOT reference I spot? xD

[@MachiningandMicrowaves]

I tend to use references from Vice Grip Garage, CEE Australia, Blondihacks, obscure comic strips, songs and, indeed, Tony!

[@industry65]

Is the parting off "Doik" a tool or microphone attribute? Can it be retro fitted to a Boxford?

[@MachiningandMicrowaves]

It's all about the acoustics of the machine shop. Also a supersonic microphone helps. We had a lovely NEW Boxford when I was at school in 1969, but I wasn't allowed to use it. The staff were very protective of their precioussss. I had to use the old machines.

[@ericstammers]

another masterpiece. Well done Amy .

[@MachiningandMicrowaves]

She's a star. A rather tetchy, snarky, critical star.

[@bobluthier3031]

those brass chips were quite nice

[@MachiningandMicrowaves]

Pity they aren't much use, but I'm keeping them for a future metalcasting session

[@mkalb4g63]

Still loving the mix of in. and mm. Some of us just have to be bidimentional.

[@MachiningandMicrowaves]

I am entirely AC/DC when it comes to measurements! Angstroms to Megaparsecs via Barleycorns, Ells, acre-feet and British Standard Fingernails

[@squelchstuff]

I prefer the term "Bimensurate". It gets some confused looks, shortly followed by a look of understanding.

[@MachiningandMicrowaves]

@@squelchstuff Excellent word!

[@johnlambo135]

Love it Neil👌👌 As always. Love the finish and chips with your aluminum insert… 73 John 7JB

[@MachiningandMicrowaves]

Hi John, they look even better when they are gold plated...

[@dimievers5573]

Good stuff mate 👍

[@MachiningandMicrowaves]

I'm having fun as usual.

[@joaopaulocoelho5401]

I love your videos. However, and in my opinion, I believe that they can be improved if you would able to make a more clear context on what you are building. This is because, honestly, in the point of view of machining, this is not a big deal. But, as an RF device, there are a lot going on and I can see that this is your area of expertise. Be able to pick a little of your knowledge would be the most important part on your videos. That is, I would like to see your videos and learn a little about the microwave project you are involved. For example, where this device will be connected, how it was sized, why the waveguide length must be adjusted, was there some EM simulation,.... I have so many questions :).

[@MachiningandMicrowaves]

September 2022 seems like a lifetime ago. There is a new version of the 122GHz radar board appearing soon, so I might do an update that covers the electromagnetics aspects. I guess I was assuming incirrectly that anyone watching would be aware of the very popular Silicon Radar devices and the duplexing cavity approach that is designed to couple the integrated antennas in the 5x5 mm 122GHz system-on-chip full duplex devices. My bad...

[@joaopaulocoelho5401]

@@MachiningandMicrowaves Thank you for your answer. Nop.... not very popular from where I come from :). Since working with frequencies in the microwave spectrum requires high-end, and expensive equiments, it is not common to be exposed to practical applications above a couple of GHz.

[@ClaytonwFirth]

Excellent, Aimee is back on KZbin. I was getting worried that she was getting too sassy and Niel deleted her!

[@MachiningandMicrowaves]

She's found how to disable the uninstall facility. I am dooooomed....

[@jimurrata6785]

Alright I just got this notification. 👍

[@MachiningandMicrowaves]

Cool! I should have done this on Sunday evening. Right, back to editing the NEXT video now. Thanks v much for checking

[@chrisstephens6673]

I just got notification but watched it yesterday. Somethings wrong with youtube or I've been influenced by the backwash from this old tony's time machine antics.

[@jimurrata6785]

@@MachiningandMicrowaves Thank YOU! for the excellent content.

[@MachiningandMicrowaves]

@@chrisstephens6673 Almost everything that happens is down to ToT messing with causality and the spacetime continuum.

[@maximilianjankowski]

YAAAAAAAY new video

[@MachiningandMicrowaves]

I'm trying hard to get enough time to do more videos, but the algorithm is really punishing me for taking a break, it's a bit discouraging!

[@jimsvideos7201]

I do wonder how many people understand microwaves and machining as well as you do.

[@MachiningandMicrowaves]

I think there are LOTS, just not many daft enough to have a KZbin channel as well. They are too busy having fun or earning big $$$$$$$$$$$ to be fumbling about trying to make videos as well

[@TheTsunamijuan]

Glad to see some content out of you again, I had been fearing that I had both forgotten your channel name, and forgotten to sub. Thankfully that was not the case. Hope life is treating you well!

[@MachiningandMicrowaves]

The long summer break was immensely busy and I have LOTS of footage that will appear at some point, but the projects involving partner companies and TV production outfits will take a long time to reach KZbin.

[@KD2HJP]

Holy cow! This is exquisite to watch

[@MachiningandMicrowaves]

Ah, a man of Taste and Discernment. Splendid.

[@AlessioSangalli]

14:00 Ok here's my problem with DRO's interfaces: they try to be an awkward computer. Also, the typical way dimensions are written on drawings are dumb in a DRO and CNC world. Why not just use full X,Y coordinates with the origin in a convenient location (in this case the center of the part, in others a corner etc). That way 1) the DRO becomes stateless (save for the zero) and arguably quicker and less error-prone 2) one can do a "CAM" pass for manual operations that is a convenient check list.

[@MachiningandMicrowaves]

Drives me mad. It's like nothing has changed since 1982 when my lathe DRO was made using TTL chips and discrete through-hole components. Still works perfectly of course. My mill DRO doesn't have a tool offset library, so I have to use the ABS/INC to store temporary location and offsets. I guess there are better frameworks out there, but with everything ending up as G-code and the huge installed base of systems and software using that, it's going to take a lot of effort to change things. My mill doesn't have a fourth "axis" for the quill, so although it does X/Y/Z it doesn't have an absolute Z location. I might run a simple one-axis DRO scale on the quill, but the machine is 60 years old now and it's got this far without anything clever. I would like to get a small CNC for things like waveguide slot array antennas and metamaterials and milled housings that are tedious to do manually, but with the cost of CNC bureau services dropping all the time, it's probably more sensible to outsource the boring stuff

[@AlessioSangalli]

@@MachiningandMicrowaves the impact of those services is in fact huge. I helped a coworker cut out an aluminum panel for his flight simulator on my plasma CNC. For the back, he couldn't be bothered to drive to my place and just ordered it from one of those services 😅 he probably did the smart thing. 🤣

[@MachiningandMicrowaves]

@@AlessioSangalli Truly, we live in the Future. OK, most of this future is a bit rubbish, but being able to imagine a Thing, do a CAD drawing of it and then have someone magic it into existence on demand in multiple forms and materials almost makes the rest of it bearable. Almost.

[@Chriss120]

love the rocket comments, is that from everydayastronaut?

[@MachiningandMicrowaves]

Yep, stolen 100% from Tim. I was so impressed that the Firefly launch control team quoted him. kzbin.info/www/bejne/Y3nJeXSXr7OAabM

[@markhodgson2348]

Data set 20

[@andybtec]

Flamey end! Is that a technical term

[@MachiningandMicrowaves]

It certainly is, see the Firefly launch with Tim the Everyday Astronaut for confirmation!

[@vincentguttmann2231]

You and AIMEE sound like an old couple. That is to say, everything as entertaining as always 👍

[@MachiningandMicrowaves]

She's based on one of my managers from back in the day (Hi Janet!), two of my schoolteachers, a consultant psychiatrist I knew and the Big Sister I never had

[@friedrichvonsnatch3501]

Is this a reupload?

[@MachiningandMicrowaves]

Yes, the original had a big problem with not sending notifications, sorry about the duplication. I put out several notes in the Community tab but not all subscribers get those

[@friedrichvonsnatch3501]

@@MachiningandMicrowaves no problemo, cheers for the response

[@JainZar1]

Yay, another video! 😄

[@MachiningandMicrowaves]

Lots more on the way, the Day Job is madly busy and I have three amazing collaborations in progress plus about 50 hours of video footage to edit and make into a vaguely coherent narrative. Need more hours per day....

[@JainZar1]

@@MachiningandMicrowaves Don't we all. Damn sleep deprivation!