Jo NZ Posted June 3, 2022 Author Share Posted June 3, 2022 2 hours ago, kpnuts said: Totally gobsmacked, this is amazing stuff Thanks! For me it's a journey into the unknown.... Link to comment Share on other sites More sharing options...
Jo NZ Posted June 5, 2022 Author Share Posted June 5, 2022 A milestone! Only a year on from when I started to create the sprockets, they are all fitted. Three chains! Along the way, of course, I had to make the gearbox, gearbox bracket and axle clamps/spring mounts (and the springs) but that doesn't matter because it all fits, the axle sprocket just misses the rear chassis rail (as it should) and the axle fits snugly behind the back of the seat back. Whoopee! And here is the gearbox support... 8 Link to comment Share on other sites More sharing options...
JeroenS Posted June 5, 2022 Share Posted June 5, 2022 Wow, Jo, that's all looking very intricate. Beautifully done! Link to comment Share on other sites More sharing options...
Jo NZ Posted July 9, 2022 Author Share Posted July 9, 2022 Thanks Jeroen! I started looking at the rest of the rear suspension, and started with the Hartford tension spring/spider. It's the same size damper as the front ones, which I'd estimated at 5" - thinking that Hartford dampers only came in 5 or 6 inch diameters. Further research showed that I was wrong - 2 1/2 ", 3" and 4" were also available. I'd put aside the front suspension because I couldn't get it to fit. Now with a 4" damper I redrew it. Here are the damper supports, damper arm, spider and the Armstrong hydraulic damper in place... Here is the 3d design - note that I made the side plates thicker so they wouldn't warp when printed I used the printed sideplates as templates. I used double sided tape to fix them to brass sheet (the right thickness) and cut them out. I also printed the brake shaft support (I've no Idea where it's from, but it's obviously from another car - just not an Austin 7) which is sandwiched between the outer support plate and the chassis bracket. Here are the components And the first attempt at assembly. Some refining of the damper arm is needed.... 4 Link to comment Share on other sites More sharing options...
klubman01 Posted July 9, 2022 Share Posted July 9, 2022 Great workmanship, great modelling, and great engineering. Also, it has been educational following the build. 3D printing opens up a whole new world of possibilities. Trevor 1 Link to comment Share on other sites More sharing options...
Malc2 Posted July 9, 2022 Share Posted July 9, 2022 ^ what he said! M. 1 Link to comment Share on other sites More sharing options...
Jo NZ Posted July 15, 2022 Author Share Posted July 15, 2022 Thanks for the praise. I'm glad you're learning something, it's been a completely new experience for me! On to the front hubs, this is the LH hub and brake drum The hubs are slightly different because of the steering arm on the LH side. I drew the RH one, and then mirrored it to provide a basis for the LH side. I tried to convert this to a mesh before I saved it.... Yes I know... The mesh included all components of both hubs, even though half of the components were hidden on the drawing. I saved it and went to bed. Next morning it worked! I made the kingpin holes on the axle vertical as I wasn't sure of the camber angle. I've guessed at 2.5° positive, so the hub is angled instead. The air scoops are drawn at 4mm (full size) - printing at 0.5mm thick, as a realistic 0.125mm thick part would be far too flimsy. I haven't added the flanges to them yet - for some reason the ducts aren't symmetrical and the 2.5° angle doesn't help either when trying to mirror. It needs more thought. There is actually a gap between the brake actuator (below the kingpin) and the backplate. It will print separately like this and save yet another drawing. I can always save it as a separate mesh if I need to print more. The kingpin is 1/16" brass (actual size 1/2" for an Austin 7) and the rod for the brake actuator 1/64" brass. In my drills that's 1.6 and 1mm 😉 PS yes I know its dusty, my cleaning tank needs filtering.... 6 Link to comment Share on other sites More sharing options...
Bandsaw Steve Posted July 24, 2022 Share Posted July 24, 2022 On 30/04/2022 at 03:03, Malc2 said: This is top work and a great and unusual model subject. My OCD is on form though, you have missed the second E from Adderley. (I spent several months at SU as part of my apprenticeship!) Malc. I often say that ‘inaccuracies’ in models are a great way to find people who know the subject well and maybe to start a conversation with them. This is a great example of that! 👍 Small ‘Inaccuracies’ of this nature add ‘character’ and are not something to be concerned about, especially given the outstanding quality of this work. Congratulations on the whole project BTW it’s highly original and beautifully executed. Just out of interest. Do you have any schematic drawings of the vehicle or are you working solely off photos? 1 Link to comment Share on other sites More sharing options...
Jo NZ Posted July 25, 2022 Author Share Posted July 25, 2022 I have extremely detailed drawings - like this one And the one in the profile The engine castings are available as drawings too, otherwise it's all photos and scaling. Some more bits - the front damper arm modified to clear the steering link Steering link end fitting Brake actuator arm (this fits to the brake cross shaft and has a rod linking it to the brake pedal) And the bit at the end of the cross shaft that pulls the brake on 8 Link to comment Share on other sites More sharing options...
kpnuts Posted July 25, 2022 Share Posted July 25, 2022 Amazing work 1 Link to comment Share on other sites More sharing options...
CrazyCrank Posted July 25, 2022 Share Posted July 25, 2022 Impressive design art, Jo👍 1 Link to comment Share on other sites More sharing options...
Jo NZ Posted August 15, 2022 Author Share Posted August 15, 2022 Having nearly got the front suspension finished, and feeling good about it, I decided to tackle the front wheels. They are Austin 7 wheels, and I foolishly thought that information for them would be easy to find... it isn't! There were 3 sizes over the life of the A7 - 19, 17 and 16 inch. I know that mine are 19" because it says so on the tyre. That narrowed it down a bit. Then I discovered that there are two spoke patterns for 19" wheels. Luckily I have the easy to model one with equally spaced spokes. I eventually got the rim width dimension from the tyre data! The rest was "derived" from photos - oh, I did find out that the spokes are 8SWG - a shade over 4mm, so that helped. Here's the wheel I drew up the rim and hub together, but without spokes as I will use pins and wire. I have shamelessly plagiarised Nick's method of producing the Bentley wheels. My wheel was easier to draw as there is only one row of spokes at the rim, and only 36 spokes, not 88. Here's the rim and hub on the jig. You may recognise the style. 😉 The back row of spokes are headed and go through the holes in the rim of the hub. I found some 0.4mm entomological pins (for butterflies etc.) which with a coat of paint will look about right. All set to go, the components look like this... The pins needed careful bending to fit through the hub rim without breaking it. Controlling them all was a nightmare until I taped them into threes And then without too much drama (once I'd got the pin length right) the back row of spokes... 13 Link to comment Share on other sites More sharing options...
Sabrejet Posted August 15, 2022 Share Posted August 15, 2022 Oh I say! That is rather lovely 1 Link to comment Share on other sites More sharing options...
Bandsaw Steve Posted August 15, 2022 Share Posted August 15, 2022 Great work. Thanks for posting those drawings too - they look great. 1 Link to comment Share on other sites More sharing options...
klubman01 Posted August 15, 2022 Share Posted August 15, 2022 Very cleverly executed. Great work. Trevor Link to comment Share on other sites More sharing options...
Alpha Juliet Posted August 15, 2022 Share Posted August 15, 2022 Following! Link to comment Share on other sites More sharing options...
Jo NZ Posted August 15, 2022 Author Share Posted August 15, 2022 (edited) Thanks all. It may be lovely, it may be cleverly executed, but the spoke angles for the outer rows of spokes are wrong. Something to chew over tomorrow.... Edited August 15, 2022 by Jo NZ Link to comment Share on other sites More sharing options...
Jo NZ Posted August 16, 2022 Author Share Posted August 16, 2022 Panic over. In a momentary lapse of reason I had incorrectly marked the spoke angles on the jig. The spokes are fine, although I still need to figure out why the tyre valve isn't quite in the right place.. And fitted to the hub... 9 Link to comment Share on other sites More sharing options...
roginoz Posted August 16, 2022 Share Posted August 16, 2022 Brilliant ! Gonna have to try this on my next motorbike model. So much more accurate looking. Link to comment Share on other sites More sharing options...
klubman01 Posted August 16, 2022 Share Posted August 16, 2022 5 hours ago, Jo NZ said: Panic over. In a momentary lapse of reason I had incorrectly marked the spoke angles on the jig. The spokes are fine, although I still need to figure out why the tyre valve isn't quite in the right place.. And fitted to the hub... That looks really good. Panic over! Trevor Link to comment Share on other sites More sharing options...
Jo NZ Posted August 22, 2022 Author Share Posted August 22, 2022 The front tyre is an Avon Speedmaster Mk II. All the main dimensions are available so it was a case of drawing a box to the profile size of the tyre and then copying the profile as best as I could. The tread pattern is very simple and was a good introduction to creating one. I used the "circular pattern" feature, but it gets a bit iffy with over 100 repeats. Saving, closing and re-starting Fusion 360 fixed it. I printed the tyre in grey resin (I have some flexible black resin on order) and slipped it over the rim before it was post-cured. There is about a 2mm interference (to allow the rim profile to show), so I was pretty pleased that it fitted! I still have to find a way of adding the various scripts to the tyre. As the surface is a bi-directional curve Fusion can't do it yet... Next is the rear wheel, which is a different size, different spoke pattern, different tyre and has a hub spinner.... 9 Link to comment Share on other sites More sharing options...
Jo NZ Posted September 13, 2022 Author Share Posted September 13, 2022 The rear wheels are 19" Rudge Whitworth. With a 4'' tyre width, the recommended rim width is 2.5", and with no other information, that's what I've used. This wheel has two rows of spokes on the rim, in the centre and on the outside web, 36 spokes at the back and 24 at the front. Here are the basic parts The jig is similar to the front wheel. I used 3 spokes on this one so it's easy to tell the difference from the front one. No spoke guidelines, I only get confused! This was my reference I had to make a shortened spoke nipple for the outer row as there isn't so much rim to go through I spent a while getting the square adjuster right on the end of the nipple, even though it's difficult to see in 1/8 scale.... First row of spokes And a completed wheel This time I've got the tyre valve in the right place - where you can get a hand to it... I've got some F69 resin to print the tyres - more on that later. Another curiosity on BM is the rear brake. The drum is attached to the rear drive sprocket and the brake actuator (from the outside handbrake) must come from another vehicle, but I've never seen one... This photo looks back to the rear axle. The drum is on the right, and on the left of the contraption is the operating arm. You can see the shoe return springs inside the drum. The front of the arm is bolted to a piece of shaped steel and rests (!) on top of the gearbox (this is a top view) Here's the basic arm, I'm going to use brass for the bit that rests on the gearbox (ooh metal again at last!) Jo 9 Link to comment Share on other sites More sharing options...
Jo NZ Posted September 16, 2022 Author Share Posted September 16, 2022 The tyres need work, I've discovered that they are much more flexible if hollowed out (currently with 1.8mm wall and 30% support) and I tried printing them at a slight angle, but the last bit to print distorts. The printer also needs to run at 25° C as the resin is so viscous. I'm trying not to make mistakes as it's twice the price of ordinary resin... The pattern on the front tyres is OK, but I'm struggling with the rears - I'm drawing a section of the tread pattern and then using "circular pattern" to cut right around the tyre. Sometimes it works, sometimes not... I will approach it with a bigger stick later on. The central patterns worked OK though. So here are the tyres.... At last I feel I'm getting somewhere! 😀 12 Link to comment Share on other sites More sharing options...
JeroenS Posted September 16, 2022 Share Posted September 16, 2022 Wow. Both to the car and your view! 1 Link to comment Share on other sites More sharing options...
Malc2 Posted September 16, 2022 Share Posted September 16, 2022 Fantastic! M. 1 Link to comment Share on other sites More sharing options...
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