356 Engine Dynometer

[Jbrooks]

Rimcanyon

Thanks, I have a VW shaft but just not long enough. I will keep the CNC in mind, and you are close to PG school. I have manual stuff but the table was too small to get the shaft in and the indexer on. Plus I hate splines, Brian did about 200 cranks cutting these, I would have lost count and screwed them up.

[Rimcanyon]

John, just read this thread. I have a CNC horizontal/vertical mill and would be happy to help with the project. I'm surprised you didn't use a VW stub mainshaft (either weld it on or machine the dyno shaft to fit the VW stub shaft).

[Jbrooks]

Well guys soon I will be able to get back to the dynometer build. Just got an e-mail from a machinist friend, Brian Block back in Ky. He has one of the shafts complete, should have the other shortly. This has been a real journey, turns out the transmission spline was way more complicated than I thought. Finding a machine shop with a horizontal milling machine large enough to hold the fixture and indexing head on the table was difficult. Then the DIN single point spline cutter had to be ground and sharpened. Brian has some huge machines and the capabilities. He builds pulling tractors and turbochargers so he is the guy for this stuff. Brian has a YouTube channel if you like machine work. Check him out. https://www.youtube.com/watch?v=uK-OJ3k6Ne8&t=1s



But the shafts are done at last. I hope to get the shafts in the next week so I can get back to work. The stock is long enough I can cut it in half and get another main shaft as a spare

Note: Capt. Evan Reese, USN ( Pee Wee) passed away comfortably at home as planned and now its just closing his estate stuff. We lost a great Naval Aviator.

[Jbrooks]

Well guys soon I will be able to get back to the dynometer build. Just got an e-mail from a machinist friend, Brian Block back in Ky. He has one of the shafts complete, should have the other shortly. This has been a real journey, turns out the transmission spline was way more complicated than I thought. Finding a machine shop with a horizontal milling machine large enough to hold the fixture and indexing head on the table was difficult. Then the DIN spline cutter had to be ground and sharpened. Brian has some huge machines and the capabilities. He builds pulling tractors and turbochargers so he is the guy for this stuff. Brian has a YouTube channel if you like machine work. Check him out.



But the shafts are done at last. I hope to get the shafts in the next week so I can get back to work. The stock is long enough I can cut it in half and get another main shaft as a spare

Note: Capt. Evan Reese, USN ( Pee Wee) passed away comfortably at home as planned and now its just closing his estate stuff. We lost a great Naval Aviator.

[roy mawbey]

John, you must have been very busy indeed with your friend. I know the situation my mum had a stroke a really bad one lost her voice and movement to get around. She lasted two years but without our help and a really good care home and carers it would have been even more awful for her. Do hope he starts to improve and it makes it easier for everyone involved. You are correct make provisions for future problems especially if living by yourself and having no family near by.

Roy

[Phil Planck]

Time very well spent John. Will keep your friend in my prayers.
I too have been delayed partially by helping family.

[JTR70]

Very sorry to hear of this John. Very unfortunate set of circumstances but at the same he's most fortunate to have old squadron brothers like yourself who have stepped in to help. I wish him well and a big thank you to you both for your service to our great country! Justin

[Jbrooks]

It's been a month since my last up date.. Sorry I have lost time. Only had two days in the shop.

A good friend and old squadron mate had a stroke the first of May. He has no wife or kids, no directives out side a of a will. His closest relative is a niece, he has only seen a couple times, she did not want the responsibility. So I got a bunch of his old squadron mates got together, saw a Judge and rescued him from the State Elder Services, and a miserable old folks warehouse.

So I am now his Guardian, we got him home with 24 hour nurses. Been installing stair lifts, cranes, wheel chair accessories in his home, figuring out bills etc. Most of the heavy lifting is done, now for the therapy and recovery.

But I did get all the coils wound and fitted. They have the same resistance and weight so the dyno progresses but just slower than planned . It's coming together

Thing are going well, but some advice "put a close friend on a bank account with $10.00 in it so they can act on your behalf, get your directives writen down and don't have a stroke.

[roy mawbey]

Well done John, its looking really good. Its not an easy job for sure!!
Roy

[Jbrooks]

Roy

welding with jigs and fixtures keeps the tolerance. Actually that part was pretty stright forward. Winding the coils has been a task. Trying to get 500 turns and having the end be at the same place is fun. It takes about an hour per coil, but they all coming up with the same weight and resistance.


but it still all fits and clearence are working out.



Thanks for following. Send old engines if you have an extra ones.....

[roy mawbey]

John just getting that Hexagon welded to a 0.004 " tolerance is really surprising ! I use the same math for standing on a pole at a certain distance to torque up my rear axle nuts to 400 ft-lbs! The job you are doing still needs a better brain than mine to understand it all. The guy who first made one must have been very bright indeed. I guess if your work training involved similar aspects then you have a head start. For example: you mention ' the more magnetic flux the more drag on the motor and the rotor will try to make the coil pack try to rotate with it. This attempted rotation of the coils is translated directly into weight'. I think I get it, then I think I don't!!

Really interesting to see your effort though.

Roy

[Jbrooks]

Thanks Phil,

It's not not too hard to understand. The hexagon and coils will have a fixed pivot on Far side and have a Load cell on this side. The coil pack will float between these points. The rotors are connected to the clutch by the shaft and spin with the engine rotation. The coils will produce and magnetic field in the rotors and this field will fight against the rotation like putting two magnets together. This will cause the hexagon to be pulled into the load cell by the rotation. I measure this in weight or pounds of force on the load cell. I will position the load cell a foot from the center of rotation. and presto I can read the torque the engine is making. once you know this torque value the rest is easy SAE HP = Torque x RPM ÷ 5252

The coils are wired in pairs 180 degrees apart. 12:00 and 6:00 together 9:00 3:00 etc. the North and South poles are also reversed in the pair. So when one is pulling the other pushes and equals out the side loading. You turn on the coils in pairs and or vary the DC voltage to change the amount magnetic flux seen by the rotors. The coils are also alternated North /South to the coil next to it. thee will also act against each other in the rotation. The more magnetic flux the more drag won the rotor and the rotor willy try to make the coil pack try to rotate with it.. This attempted rotation of the coils is translated directly into weight.


easy to calibrate also. you make a 2 foot long bar that will attach to the Hexagon above the load cell . The hang a weight on the bar and see what the load cell says. 2 foot bar 100 pound weight = 200 ft pounds. 50 pound weight = 100 ft-lbs. Its really pretty simple if you do the math.

[Phil Planck]

Good progress John. Been following and trying to understand.

[Jbrooks]

Ran out of wire.. Awaiting parts. Story of my life. Got the rotors cleaned and coated, I now have "RRR" Ruby Red Rotors. Alignment and clearances look good so we progress. I need to do some more sheet metal fab and trimming. The coil cap mounts overlap about 2-3mm in the inner corners. And I have 72 holes to bore and tap in the octagon. But it still fits so I am a happy camper.

thanks for looking

[JTR70]

Mind blowing Electrical fabrication going into this field coil unit. I'd bet you have the skill to convert a generator to an alternator. Keep up the amazing work...