February 3, 2018
Sadly the Official run did not go to plan. It was a beautiful chilly day on the lake. Had a load of people show up to watch and spent about 2 hours setting up all the cones and equipment. We were around T-minus 5 minutes and getting ready to start the turbine up after filling the fuel tanks. We were moments from starting the engine and a massive wind front crossed the lake towards us and the freezing wind chill not only killed every battery powered device we had out on the lake, it froze the propane starter fuel and burnt out the glow plug in the engine. While the engine could have been fixed with some time. All of the timing and camera equipment was out of commission, rendering the attempt not possible. While sad that the attempt was ruined by weather, we did atleast get to have a pizza party with everyone and hangout for a few hours. Til next time…
January 29, 2018
Well the project is back in motion. The engine has been repaired by Dreamworks RC in Florida and I got myself a king sized snow racer to build Jet Sled 2.0. The bay finally froze over after 3 years of waiting and the run is 5 days away. Need 2 days to finish putting the sled together.
May 5, 2016
I finally got an email response from Guinness World Records to discuss what I’m doing, hopefully all goes well.
February 26, 2016
Confirmed the starter fried the ecu. It wasn’t the voltage, it was the fact that backEMF is reverse polarity that did most of the damage. Gonna need a high power diode on the starter to prevent the issue from happening again and gonna need to disassemble the starter and repair the clutch and repair/replace the motor with a new one, the engine is over 15 years old ya know lol.
While the sled did perform well, for the sake of run times, I thinking of designing an aerodynamic thrust augmentor to trade some exhaust velocity for extra thrust. I also guess it’s a blessing in disguise as it gives me a year to get into better physical shape and get a little lighter to reduce the ski friction some more. My dataset predicts about 89.18N of static ski friction so that is a great deal of the engine’s 200N of thrust wasted so there is much room for improvement.
February 21, 2016
Took the sled out to the cottage to test on the lake while I wait for parts to come in for the starter bypass. On the first run I forgot to film it, but it went pretty good. Got up to 50 km/h according to the gps before hitting some solid bare ice and spinning out, by the time I got back to shore the tank was out so I went to eat lunch. Definitely gonna need more fuel. After lunch I setup for the second run, all was good, started it up in the heated garage and carried it to the lake, sat down and pinned the throttle toward the other end of the lake as the conditions were better. 3 seconds after the engine reach full speed, everything just shut off. The ecu monitor said pump limit reached which was odd, the fuel was on. Once the engine spooled down a bit, I noticed the starter was on but the turbine rpm was 0 so I hit the ECU battery disconnect. The starter was still running so I diconnected the starter battery.
After getting it back in the garage to look at I found a few things damaged. First, the starter MOSFET inside the ecu was fused closed, none of the solenoids, pump, or glow work. My guess is the starter clutch got stuck during the startup sequence and when the turbine went full throttle, the backEMF from the starter brokedown the MOSFET and shorted all the power circuits inside the ECU. Tomorrow I have to take apart the ECU since the warranty is null and see how bad it is and if it’s possibly fixable and test all the components to see what I have to replace. The starter bearings or the clutch also sounds like its fried because it makes an awful noise when on.
Once I get new electronics and a starter, I’ll be sending it in for service to finally fix the NGV rubbing since I’m spending money on it now and ended my season prematurely as I had planned on doing a speed run next weekend if this test would have passed. Also gonna get the PC datalogging dongle and new 90deg elbows for the connectors inside the engine so I can properly use the front cover. I gonna try and make a dual arm starter mount because the one armed mount on it now flexes and always comes loose from shit threaded screw holes and looks like it is held together with JB Weld lol. Dual arm will also be handy because I will be able to isolate the starter to make the bypass easier. I definitely gonna need diode protection on the bypass to stop the ecu from getting fried again in the future though.
February 13, 2016
Well I soldered up the new MOSFET. Turns out, a P-channel is not what I needed and a so-called electronics guy online was wrong. I had a feeling he was wrong but what can I do. So now I’m trying to source out a N-Channel MOSFET and I have to figure out the wiring as wiring it on the negative side of things is alot more complicated because the starter is a part of the turbine and its a common ground for everything plugged into the ECU. Yay for being a simple fix…not 😛
February 7, 2016
Well the lake didn’t freeze over, now it’s mild, and the snow is gone, there’s always next year. Spent some time soldering up the safety tether to a harness and test fitted that, still deciding the best place to mount it though so I don’t have any dead zones for the tether getting tangled and not pulling if I fall off.
I also failed to solder a MOSFET to the starter harness to bypass the low voltage electronics to get a faster startup sequence. I get 3.5A@8.4V using the ecu battery directly, but with a 12V battery, the starter pulls 18A on the ammeter and it sounds like it spools a hell of a lot faster. Not sure why the drastic amp difference over 3.6V but I’ll take it. So I’ll have a small 12.6V volt battery running the ECU through a 5V volt regulator, a 8.4V battery running the fuel pump, and another large 12.6V battery running the starter, which could be mounted but because the engine needs a cool down after running, there is no real reason to mount it. I’ll just plug it back in before triggering the shutdown sequence, saves like 2 pounds..
I had 3 MOSFET’s to solder with and broke them all. The first one broke while getting ready to encase it after soldering, second one melted while soldering, and the third one broke while the epoxy was hardening, so now I’m waiting for a much bigger MOSFET. This time though, I just gonna double heat shrink the whole thing and plug the ends with hot glue. I’m also in definite need of another soldering tip, this one is finished me thinks lol.
I’d mount some wheels and do some summer testing but I’d have no brakes, the pedal is useless against pavement. Can’t wait to do a full cycle test with the starter running at full rated power this time. Maybe I’ll get lucky and find a frozen lake up north before the spring hits. They been getting pounded with snow for days.
February 1, 2016
Still no answer from city hall. Guess the lack of good ice on the lake means it doesn’t matter to reply back at all lol.
January 9, 2016
Readjusted the EGT thermocouple and fixed the overheat issue which was throttling the engine back because it was about 3mm too far in the exhaust. No one home so I just took it for a rip down the street, works good, snow needs to be a tad more fluffy for steering to work properly though, its hard packed like ice right now. Waiting for a tether kill switch and have to make a setup to mount the 2 batteries to and figure out where to mount another fuel tank, pretty sure I gonna need it.
December 20, 2015
Got a paper thin layer of snow on the ground last night, Guess where I’m going. Guess what I forgot…lol…pump for the fuel tank. Macgyver to the rescue. Just reversed the fuel lines, put the engine line in the fuel can and ran the pump prime function for what felt like an eternity. Back to business. Well after finding an abandoned paved trail, I setup and handed my step dad the phone.
I’d say that went pretty good for the first ground test. Constantly driving over gravel under the paper thin snow didn’t help. Still scared the living shit out of me though. Hopefully the steering is better in real snow cause I had none haha. Also still got a few thousand RPM to ring out of the turbine and to plan my fuel very carefully, probably gonna need a bigger tank…
December 16, 2015
Got a reply from city hall. Got to wait until the city meeting on January 15, 2016 for winterfest to get an official answer.
December 15, 2015
Just went public. Sent a long email to City Hall because the day I decided on was the same day as the winter festival and the plans were already in motion. Wish me luck. Hopefully their response isn’t “LOL”. Also got the throttle mounted and calibrated. Bring the snow…..please.
November 26, 2015
New clamps are finished, 1 full power run later and all is a go. Was funny watching dad hold on to it for dear life for sure. Still waiting on the throttle control in the mail though. Now I have to permanently mount everything and clean it up.
November 25, 2015
Got the proper fuel lines in the mail today and mounted them on. Had some daylight left and no one to film, but screw it. Full power we go, it was deafening. Found a weak point though, I need to make some steel shims for the mount, apparently 2 6 bolt clamps wasn’t enough to prevent the engine from pushing itself out of the clamp at full power.
November 21, 2015
Quick update here. I fixed the parameters on the ECU to get a more efficient startup while I wait for the fuel lines, no full power today.
November 15, 2015
This is the beginning of my project. I had recently bought a AMT 450 turbine from the states and spent a over a month deciding what I was going to do with it. I thought strapping it to a vehicle and going for a spin would be cool but it had to be small. At some point I thought of a snow racer. It’s small, light, compact, and easy to move and work on. Perfect.
With that idea, a facebook news article of Guy Martin setting the gravity snow sled record popped up with wicked timing. After watching it and doing some research, I found that there was no powered record at all and that just set everything in stone.
After making an engine mount and welding it onto the snow racer for most of the weekend and bolting the engine to it, it just looked completely raw and pure badass. So I MacGyvered some fuel plumbing out of some leftover r/c fuel line and booted up the camera. Here we go…
My total rush was ruined by the fuel line bursting but that sound it made was irresistible and it called for more. Time to order the proper stuff.