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lukej

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Everything posted by lukej

  1. Glad I have agreement from someone! Luke
  2. That would be amazing, can you order 2x Tamiya Reinforced Tyres Type C 54256 for me please? Thanks! Luke
  3. Overnight Progress Report Purchases Tamiya Medium-Narrow Hard Inner Foam 53436 - On hand Tamiya Medium-Narrow Dish Wheel 24mm (53475) - On hand Challenges Tamiya Reinforced Tyres Type C (54256) - On hand, thanks @wtcc5 I have found one place that claims to have stock of the tyres, it’s a German company that I’ve heard of (Modellbau-Seidel), but their website looks like it’s from the 1990s and I’m a little uneasy about that. Maybe one of my friends from there can vouch for them, @wtcc5? Onto the search for other things! Luke
  4. I see what you’re saying, thank you. Turns out the force outcomes were correct, but the area in the equation wrong - frontal area was 199.5cm^2, so yes it needs that adjustment. To be honest, I was relying on tired 4am brain and Engineers Toolbox to do the maths I wasn’t quite awake enough for. One day I’ll learn! On a separate point, the cube was used for consistency with previous equations, so yes, we could have just used the frontal area but a vertical plane has a worse coefficient (1.17). With that said, it’s an irrelevance because and car would have a much better profile than a cube anyhow (a road going BRZ has a Cd of 0.27). Luke
  5. Going down the rabbit hole just now on parts, particularly tyres and tyre inserts, and I discover the first potential issue - my wheels aren’t correct. To the naked eye, they’re a white dish wheel as they should be, they’re zero offset just as the pictures show, but they’re 2mm too wide for the inserts. **** it! From the manual, there can be no doubting that I need the closed foam moulded inserts, and these only exist for the 24mm medium-narrow wheels (53475). Guess I’ll be buying some of those too then… Anyway, it’s an easily solvable problem, and it comes with answers to the questions I had on inserts and tyres as you’ll see below. For inserts I have the voice of soft (53435), medium (53582), or firm (53435); and I’ve gone for firm as these would suit carpet should I ever give the car a run. For tyres, with the insert choice above it’s an easy decision and I’ll take 54256 Reinforced Tyres Type C for Carpet. Time to order those parts before bed then! Luke
  6. Thank you guys for the interactions already. Turns out there’s nothing like a kit buying ban to spur me on! Luke
  7. I found one NIP on Mercari via Buyee, let's see how long it takes to ship! Luke
  8. I feel like this is the one sentiment Tamiya preys on with collectors like you, and dare I say it, I... Luke
  9. TW: The following thread contains graphic detail about a man's continued addiction to fast Tamiyas, especially ones with shiny blue parts. With that out of the way, and with it being obvious that I've bought yet another high-end NIB kit, I'd like to share the timeline of how we got here. Early December 2022 - I buy an M-05 from the local hobby shop to build quickly, because: a) I should finish a build for once. b) I'd like to play with FWD cars for a change. c) I'd have a car I'm less precious about to send out into the car park at home. Now I did build the M-05 quickly, and it is mostly complete (I need to order a steering turnbuckle and improve the alignment), but that meant it only got fired around the lounge a few times before my idle mind pushed me to the internet again. Mid December 2022 - I acquire 2 more NIB cars, an M-08R from Tamico, and an M-07R with a surplus of hop-ups from a nice man named Jamie who, having listed the car for sale on eBay was only too happy to relieve me of some of my money. With the M-05 yet to see a body shell, which I told Mrs Lukej was due to the lack of time and suitable conditions in which to paint it , permission for the additional purchases was granted - the M-08 is clearly necessary or how else would I know which M chassis variant is best for the RC club that I don't race at? Anyway, Jamie will become important come late February 2023, so remember that. Late December 2022 - On one of my usual internet trawls, I discover a man on eBay/Facebook with a NIP Atsushi Hara Twister 2.2 ESC, and whilst I already have a used one of those for my TRF 415MSXX MRE build, I'm sure we can all agree that such an important car deserves a brand new one can't we? Good. Early January 2023 - Whilst working on the other side of the world, the seller of the NIP Hara ESC and I agree terms outside of eBay (because they wanted a massive cut & I don't like that), so where he's in Singapore & I'm in New Zealand at this point the time zones align nicely for us to talk things through. In doing so, as is often the way, I also discover a reason to spend more money - there's a NIP Tamiya Volac MS C3 available on eBay and a Transpeed Brushless 5T motor too. Clearly I need to buy these, because knowing me as I do, there's undoubtedly a project in my future that each of these can be fitted to (but not the same one, the ESC is for brushed motors, so they're not compatible). Mid January - Mid February 2023 - Without the distractions of being at home with both Mrs Lukej and my many many build projects, and having spent most of the NZ trip wondering what car to put my new acquisitions into, I end up spending a significant amount of time online either buying parts for the cars I already have (thank you Dai Sakaguchi) or in some cases buying parts for cars I'd like to have (thank you eBay). For scale, here's a picture the OH sent me with my stack of boxes 1/3 of the way through my journey to the other side of the world. This Week - I think it's fair to say that at this point I've added a few nice items to my collection, but none of them were suitable for that Volac ESC, and that was a solvable problem - enter my new friend Jamie, who just so happened to have a NIB TB Evo5 MS for sale. The Solution To the build then! The TB Evo5 MS has been described as many things, @wtcc5 called it "the shaft drive legend", @_miga_ "the ultimate weapon for technical courses", RC Scrapyard gave it 4.5 stars, whilst Tamiya themselves went for "the strongest shaft driven 4WD", and Mrs Lukej it's called something else altogether - though this possibly connects to the 2 other cars I bought at the same time, thanks to Jamie and his ability to find bargains on Japanese auction sites. Moving on. With Royal Mail delivering the kit to me this morning, and already having a clear idea for the build, I can start to organise everything ready for assembly. The plan is to build the car up as it was shown to the public for the first time, and that means: Pulling the instructions out of the box to get an idea of what parts needed acquiring. Tamiya Volac MS C3 ESC (42123) - On hand Tamiya Super Stock Type BZ Motor (53930) - On hand Tamiya Medium-Narrow Hard Inner Foam 53436 - On hand Tamiya Medium-Narrow Dish Wheel 24mm (53475) - On hand Tamiya Reinforced Tyres Type C (54256) - On hand, thanks @wtcc5 Tamiya 3700HV Stick Pack Battery (55094) - Ordered through Mercari, stuck in a warehouse somewhere in Japan Tamiya Honda NSX GT 2005 Lightweight Body Parts Set (47353) - Ordered through Mercari, stuck in a warehouse somewhere in Japan Futaba R603FS FASST Receiver - On hand/To buy - The one I have is NIP but has the incorrect label Futaba servo, possibly an S9550 - To buy There's a bit of shopping still to do, but it made sense to organise what I had ready to go. First, the Volac MS C3 can be added to the box. Then the Tamiya 0 offset dish wheels. The Super Stock Type BZ will arrive later this week, just before I head off to the Arctic Circle for an event, and that means no building for a week or so. Quick one, but does anyone of you know why Tamiya installed the Type BZ at release instead of the Type RZ or Type TZ? They say the BZ is for off-road cars, so an RZ would make most sense for the on-road use case or even a TZ despite it being an endurance/low speed circuit motor. Lapland trip stopping play, I guess I'll focus on the shopping list/research and head to Tamiya's online product catalogue for some better photos. The receiver is a Futaba R603FS, and whilst I'd like NIP I doubt that'll show up. Unfortunately, the only example I've found is on eBay as part of a Futaba 4PK bundle from reseller, and it's all for the low low price of £841.51! Off to Mercari to see what I can dredge up... This stick pack is going to be a bit of a pain to source, I'd actually won one on Mercari last night only for the seller to refuse international shipping. If any of you have the correct one that you wouldn't mind me relieving you of I'd be interested in a discussion. From this close up I can say that it needs to be the type with GP NIMH cells, the Sanyo NICD type came later. Our last, and possibly the most challenging search, is to determine what servo was in the car? From the next picture we know it's a Futaba, and I'd take an educated guess that it's an S9550 as this is also what Marc Rheinard was using one year earlier in his TRF 415MSXX at the Reedy Race. It's still a guess though, and these are about as rare as hens teeth. I need 3 of these for various builds and have so far found none, anyone able to help? Additional photos of the car from Tamiya are about the best reference material I'll get. Top. Underside. Note the blue label on the stick pack. All that's left is the minor detail of sourcing an NSX body, but that's the one pictured in the late stages of the manual so it's the one I'm going for and obviously it'll be treated to a Satoshi Maezumi style paint job. So that's kind of it for now team, guess I'm off down the rabbit hole to find these parts, especially as I'm on a buying ban from the OH, no more kits until I finish a build apparently, the cheek of it! Luke
  10. Car 2 of 4 from the past week's spending spree... This one will be built to launch specs, because box art isn't a thing, but essentially as per the images in the instruction booklet. Luke
  11. Hi, Thats exactly as they’re set up. Luke
  12. It doesn’t scale, because drag losses square with speed and as such grow rapidly with both speed and area. To be honest, this is where the algebra goes from high-school to university levels and if we were to calculate drag as it relates to all aspects of a car we end up down a rabbit hole looking at friction losses across drivetrains etc., anyway. To calculate the aerodynamic drag acting on the car, we use the equation: Fd = 0.5 x p x u^2 x A x Cd for reference: Fd = drag force (N) p = liquid density (kg/m^3) u = relative velocity (m/s) A = reference area (cm^2) Cd = drag coefficient To make things simple, we can plug in the numbers based on the previously referenced TT-02 club racer, as ever this will combine some true values with some assumed ones, as below: p = 1.204 (approximately the density of air) u = 27.778 (100kph in m/s) A = 199.5* Cd = 1.05 (the drag coefficient of a cube/cuboid) *To approximate area I measured a standard Tamiya 1:10 Touring body (Subaru BRZ R&D Sport #59607), but made it a cube to ease the calculation for both area (A) and coefficient of drag (Cd). So for a 1/10 cube of a Subaru BRZ RC car, the aerodynamic drag at 100kph is calculated as: 0.5 x 1.204 x 27.778^2 x 199.5 x 1.05, giving us an Fd of 9.73N To show the relationship with speed, if we halve the velocity to 13.889m/s, we get a value of 2.4326N. Equally, if we increase the speed to 55.556m/s, we get a value of 38.92N. Now, if we scale the car up to 1/1, multiply the frontal area by 100, so 199.5 becomes 19,950 and so the equation is: 0.5 x 1.204 x 27.778^2 x 19,950 x 1.05, giving us an Fd of 973N. As I said at the top of the comment, drag squares with speed, so at 13.889m/s, we get a value of 243.26N and at 55.556m/s, we get a value of 3892N. This also touches on what @Nikko85 said about cross sectional area, so when we take a 1/10 car and scale it to 1/1 we now have to deal with a car 1000 times the weight, with components that have 100 times the cross sectional area, and an aerodynamic drag penalty that’s also 100 times as much. With all this to overcome, you can quickly see how speed can be lost. There ends my second TED Talk 😂 Luke
  13. Having just bought my first FF-03 (as you know @wtcc5), I decided to re-read this whole thread and it's sparked another hunting spree in me. I will find all of the parts for the R to be full hop-up, I will try to find an Evo kit, and I also really want to build a KR-MF so that I can have it in the collection with the KRV4 and the KRF interpretation I have planned. Coincidentally, have you seen Kentech's latest blog about TITC where he talks about the updated TRF420X he saw at the track. There were two variants, but one looked like it had a shorter version of the SSBB dampers. We can live in hope! Luke
  14. Glad I'm not the only one with this problem. I bought a second set of pliers because I couldn't get the tips, but I also have a 3D printer now so... Luke
  15. Can you send me some more pictures of the blue tool set & KTC set please. Thanks
  16. That’s awesome, a great idea and your execution is on point as always! Luke
  17. The HPI Pro4 Hara Edition from 2004 😬 Luke
  18. A very understanding wife. With only 4 cars currently on the wish list, and 1 of those I suspect being unobtainable, the collection stands at 20 cars! Luke
  19. Bought my 3rd NIB kit in 2 days and my 4th in a week. Mrs lukej is very understanding and I am now the owner of these beauties: - TRF 417X - TRF 415MS - TB Evo5 MS - FF-03R It’s been a good week! Luke
  20. Yeah I just halved the number above not the full size! That’ll teach me not to check my working out! Luke
  21. I am now a member of the club, having proudly won a NIB FF-03R on eBay, and maybe, if I’m lucky @wtcc5 will help me build a second as a KR-MF 😉 Luke
  22. Nope, aerodynamic drag doesn’t rise in a linear fashion, friction losses grow as does inertia. Oh, and traction (assuming tyres were equal) would stay the same. Luke
  23. Whilst good for marketing, scale as it relates to speed has never been an accurate statistic, because amongst other things it ignores that aerodynamic drag and mass do not increase in a linear fashion. To get a better idea of what a 1/1 version of an RC car would be, let’s first understand some basic maths and use the example of a snooker table’s surface area (2 axes) at three common sizes: - A full size snooker table is 12ft x 6ft, and has a surface area of 72sqft. - A 3/4 size snooker table is 9ft x 4.5ft and has a surface area of 41.5sqft or ~57.6% that of a full size table. - A 1/2 size snooker table is 6ft x 3 ft and has a surface area of 18sqft or ~25% that of a full size table. With the above in mind, let’s give an rc car some values that we can appropriately scale: - A typical TT-02 club racer has a mass of 1.35kgs. - Let’s make the TT-02 a cube for ease and give it an assumed volume of 1 (1w x 1h x 1d). To calculate density we rearrange the formula mass = density x volume as density = mass / volume so density = 1.35 / 1 meaning density is 1.35. To the 1/1 scale vehicle then, we have to multiply the volume by a factor of 10 in each axis so 10w x 10h x 10d gives us a volume of 1000. Which allows us to calculate mass as being 1350kg (1.35 x 1000). To work out the top speed of a 1/1 version then, we’d need to understand how each other factor of the car changes with scale but it wouldn’t simply be 1/10 speed multiplied by 10. If you wanted to calculate the mass of any RC car at 1/1 scale, and simplifying the above to do so, put your car on a scale and weigh it then follow the formula below relative to whatever size your RC car is: 1/12 scale mass x 1728 1/10 scale mass x 1000 1/8 scale mass x 512 1/5 scale mass x 125 If you’ve a vehicle at any other scale and want to calculate its mass at 1/1, cube the value on the right side of the scale and you’ll get your multiplier. Anyway, that was very long winded, resolves nothing and took me an age to type. Thank you for coming to my TED Talk! Luke
  24. Like so many of you I think it’ll be new battery tech. The more energy dense a battery, the smaller & lighter it can be made for the same performance and that has benefits for racing, vintage builds and hobbyists. For racers, it would allow better weight placement within a chassis - think lower CoG & roll centre, but also more broadly the placement of a mass in the chassis can affect the front/rear and left/right balances. For vintage builds, a more energy dense LiPo cell could be packages as a hard case in saddle and stick formations to fit into older chassis. For hobbyists, new tech supersedes old and drives the cost down. Thinking of other developments, there’s none that spring to mind which benefit the whole hobby so broadly. Luke
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