Roman

Members
  • Content count

    4,125
  • Joined

  • Last visited

  • Days Won

    8

Roman last won the day on March 14

Roman had the most liked content!

Community Reputation

9,138 Excellent

About Roman

  • Rank
    RHS Master

Profile Information

  • Gender
    Not Telling

Converted

  • Local Area
    Auckland
  1. +1 Black and Silver. Body coloured engine parts just look out of place.
  2. Arduino stuff/ programing/so cheap

    Hey thanks - That's cool but the Teensy is way gruntier It can have 32 bit variables instead of 8, and it's got a floating point processor so it doesnt take a zillion years to calculate a float. And processor is many times faster. Canbus itself is usually 2 chips (a transciever which converts canbus frames to SPI or similar, and one that acts as a filter for messages) My main dash unit / ignition trim computer thingy will be trying to do a lot of stuff at once, so faster the better.
  3. Arduino stuff/ programing/so cheap

    Okay soooooo Arduino Due. Its canbus can work between two Arduino Dues, but you need a transceiver chip to make it work with a "proper" canbus. So bought some transceivers, which apon arrival I realised they are the wrong ones. D'oh. So rethinking it some more, although I like the fast speed of the Due, and the fact that it's got a native canbus thats easier to write for. Eventually I want to add some other canbus devices in addition to ECU and dash, in which case I dont need or want the bulk of a Mega sized arduino board. So thats the next problem, if I write a bunch of code for a Due, and then want to add a smaller arduino device I'd need to rewrite all the code rather than just chop snips out of it to make it work. So from here. I found out about the Teensy. Teensy V3.6 is 180mhz 32 bit and basically trumps the Due in every conceivable way while being exceptionally tiny! And it's arduino sketch compatible. https://www.sparkfun.com/products/14057 It's also got 2 canbus lines and can use this exceptionally small double transducer. https://www.tindie.com/products/Fusion/dual-can-bus-adapter-for-teensy-35-36/ So since it's small enough and not incredibly cost prohibitive I'll probably make everything on my bus use a teensy + that transceiver for sake of keeping the code easy. Then 3d print some housings to suit. Now that I understand things a bit better I dont need to use any of the shields I had. Should be nice and compact for whatever they end up doing.
  4. DIY Fuel injection thread.

    Agree with that 100% Look up virtual dyno. It's great for quantifying differences from road tuning if you can minimize variables. I had a situation where I gained 20hp and heeeaaps of midrange power and the car felt slower.
  5. DIY Fuel injection thread.

    You definitely don't need a dyno especially for a low power car. As you can just nang it up the open road and get some good results because you aren't accelerating too fast. Also it's really easy to find the timing plateau. Also, it's immensely satisfying and heaps of fun. In my dyno session I gained nothing over my road tune.
  6. DIY Fuel injection thread.

    8% more power is another way to think about it... Which isnt bad when you stop to think that it pays for itself over time with the economy difference.
  7. DIY Fuel injection thread.

    Off topic to the above, but. My cars exhaust noise is really sensitive to ignition timing. Like if I dont have enough timing its way louder and tinny sounding. And also the oxy sensor readings dont seem right when the engine is cold. Like it will say 16:1 when it is chokingly rich at the exhaust pipe. So for ages its always been much louder when its cold, but I put it down to either an exhaust leak that closes up once hot, or... something. But so thought I'd experiment by adding some ignition timing when cold. Annnnddd car is now way quieter when cold! And the air fuel ratios showed closer to what seems accurate, now shows at about 13:1 So I reduced my cold fuel enrichments until I was at my goal AFR again, and now my fuel usage when cold has decreased: I'm gonna call that a win! I think its because when the engine is cold the fuel and air just hasnt mixed very well at all... Lots of the fuel will still be droplets that dont start evaporating until ignition has started. So it takes way longer to burn properly (relatively speaking) Which explains both why it was louder and why oxy sensor readings werent right. As there is still uncombusted air and fuel exiting the exhaust port if you dont have enough timing. I've always had on my mind that you need extra fuel for cold conditions but never thought about ignition at all.
  8. Success! Edges need trimming but you get the idea. Pva glue over plaster was the good combo. Then a little wax for good measure. Carbon sleeve is the best! The inside is super smooth and tgecoutside feels like crocodile skin or something. The biaxial weave is really cool. Gonna order a bunch of different sizes I think. This one is probably a tad flimsy with only one layer of sleeve but two will be sweet with a 6k weave I think. Or maybe just go 12k single. But it's probably lighter than the bolts that would hold it in place. Only about 25 more prototypes and I'll have a usable part haha
  9. I think pva glue might be the answer for sealing the mold. Its water soluble, fairly thick so doesnt massively soak in, doesn't strengthen the plaster too much, super smooth finish, non toxic and cheaaap. And can wax / pva release agent over the top too. Will give it a go.
  10. Also my latest CF related abomination I thought it would be an interesting idea to try make some molds for a destructable inner core that I could easily make a bunch of. So firstly drew up a trumpet shape that I wanted to make (omitted the return curves for simplicity for starters) Then made a 2 piece mold following the inner surface shape and added some locating tabs 3d printed it like so and filled it up with plaster It took a few goes to figure out how to avoid bubbles in the finish and blah blah, but got a nice result eventually. So the great thing about the plaster is that just a quick whisk of sand paper and you've gotten rid of any layer lines from the 3d printing. Get a super smooth finish which is awesome. But the big problem is that its massively porous. So I thought giving it a coat of epoxy would give it a nice glossy finish that the final part would seperate nicely from. So did that, left it for a day and it ended up with a really nice glossy finish. So PVA'd over this (No wax which was a mistake. mistakes were made. I'm stupid. etc) Then bunged some CF sleeve over the top and some normal matting at the bottom to cover over where it's thin. Then vacuum bagged this, with wet layup. Had some problems with the bag not being able to tighten fully up to the part, as I didnt allow enough bag size essentially. So I had to fiddle with a it a bit which ruined the outer finish and creased part of it. Bums. Annnnddd then my second problem. Coating the plaster with epoxy to seal it creates this rediculously hard outer layer that is almost impossible to smash haha. Damnit. Underneath the parts I've managed to break/pick off, it's got a super nice finish where it was up against the glossy epoxy finish on the plaster. The PVA seems to be doing its job to some extent as when you pick some of it off there's a clean seperation. But it just seems mechnically locked in place since theres still a curve all of the way around sticking to the part, and both the part and the plaster are stupidly rigid. But I'm really happy with what the internal finish looks like where it was up against the mold. I dont have the patience to get this entire part unstuck, and there's no point because the outer of it looks yuck anyway. So I'll try find a better way of making that center core part and try again. I've ordered some PVA filament which is dissolvable, so I could 3d print a core that just washes out after. But it takes ages to print, need to sand the layer lines every time, and is expensive. So if I can make plaster or something similar work (any ideas for another something similar to use?) I'll stick with that. But if the plaster needs epoxy or similar every time, PVA might just be more cost effective as well as a lot less messy. (It's stupidly good fun pouring plaster and then seeing something cool come out of a mold though) I think my next iteration of this piece will be good. My resin infusion is working awesomely now so I'll do that again for the next iteration. It's much easier to sort out any of the bagging issues when the bag doesnt stick to the part because it's already wet with epoxy. TL;DR: Lots of time and materials, have produced nothing useful since previous posts, still have hope for non shit parts in future
  11. Haha this cracked me up http://www.motoiq.com/MagazineArticles/ID/1704/PageID/2400/Project-Miatabusa-Part-43--The-Intake-Manifold.aspx
  12. AMR300 and AMR500 talk

    Shit these things are cool.
  13. Arduino stuff/ programing/so cheap

    Hahahaha awesome. I'm at the stage of "Why the fuck did I put all those houses there and what do I do from here" then look at my code for 10 mins and go do something else hahaha. Need to start again with the canbus code for the arduino Due which is waaayyy simpler. Too many 1/10th finished projects at the moment haha.
  14. Yeah it seems counter intuitive but with epoxy it starts going off in the pot way quicker than when its on a part. Because it builds up heat which causes the epoxy around it to build up more heat and it gets in an exponential cycle. Can start smoking and melt your pot if its plastic! but when laid out in a thin layer the part its on helps cool it and it stops this process. Like your pot might last 15 mins or less but your pieces of cloth could sit there with epoxy brushed on for hours before even starting to cure. So if you get the epoxy onto the cuts of cloth asap and then there isnt really any time pressure anymore. And it gives the epoxy a bit of time to let off some of the gas that can cause bubbles in your surface finish.
  15. Which ever side is up against the mold is what comes out nice. So if you lay up against the light directly you'll get a nice looking inside finish that no one will ever see haha. +1 to just waxing / PVA the shit out of your headlight lense and then make a mold, then layup CF into this. There are a few videos posted earlier in this thread on Youtube, by Easy Composites I think its called. Watch all their stuff its awesome! I've found the best way to avoid bubbles when wet layup is I bought some big shallow plastic bins, and I'll wet layup the sheets (already cut to shape) and then let them sit for 5-10 mins. Then drape them onto the part. And get CF with a fine weave or it frays like crazy and it's bloody hard to do anything with.