2017 Tasman Cup Race 3 Shelmore Park

[dangermouse]

Thanks for the comments

I would appreciate any suggestions from anyone around the comments. I am always looking to

Improve the car. Aside from the fun of running in the proxy I am thinking of building 4 or 5 of these cars to run as a house class up here.

 

Does the comment " is the not as solid in the slot " reflect a weight issue or centre of gravity? Any suggestions on how I can improve that.

"I found it a touch flighty" also any thoughts on why and how I might improve this

 

Luckily it didn't fall out of the slot a lot 😀

 

Is there a photo of Dave chassis

always looking for ideas for next year's car

[boss_302's_son]

Dangermouse - It felt light and that it may de-slot so didn't instil much confidence until I got my eye in. I would suggest maybe testing with a little bit of weight added and shift it around to see if it helps, may help make it feel more consistent - a good car though and I was only nitpicking so there was a bit more detail for the comments.

 

Dave's chassis uses a 'pod' like set-up. The brass chassis is in two pieces connected by a tube in the centre and soldered together down the outside with piano wire. This in theory makes the rear pivot off the front half of the chassis, via the tube, but the amount of movement is controlled by the piano wire - different diameter wire would give different amounts of flex. I think there are similar ones being run this year.

 

Now I just have to finish my track so I can build and test my own car!

[manimmal]

Thank you for your feedback, and of course thanks to all for organising and participating.

 

I did swap out the motor on #78 prior to sending the car thinking that was my issue, so i was aware of my speed issue. Strange really that i didn't think to change my gear ratio? Oh well, there's always next year...

 

Chris

[dangermouse]

Thanks for the feedback Callan - I think I know the type of chassis - I had a plan for a torsion type chassis for this year's car but time got away from me so I tweaked #30 from last year. May have to do something about that for next year.

 

cheers

David

[Peter Gunn]

Hi Boss 302 ( son ) the brakes issue is it the gearing i am at 9x24 last year ran at 9x25 and was wondering if i should have dropped it to 9x 23 find these motors usually pretty reliable in the braking dept for a ff.

[kalbfellp]

Here is a pic of Dave'schassis.

 

 

Think it is pretty heavy around 65 grams.Tassie tyres.Gearing would be 9 24 OR 9 23.

[kalbfellp]

Most of the action from this Race

 

 

Minimal leading Rolling thunder

 

 

Dangermouse's BRM Back again this year

 

 

Pauls nice Honda

 

 

Shadows Emeryson another nice car!

 

 

Stubbos Brabham seems down on power.

 

 

FPR7 Elfin on the outside of Scozz Lotus,now much better.

 

 

Lennies tired looking Cooper.

 

 

Johns neat Brabham,neat car.

 

 

Nice to see a new entrant and a good start with the car.

 

 

Kids Origami Lola,unchanged from last year.

 

 

Charles Brabham, bad tyre choice seems to be hampering this car.

 

 

Olds Nice Cooper very fast car.

 

 

Keiths Lotus and DM's BRM

 

 

Spoons Ferguson,nice paint.

 

 

Rolling thunder and Diffinity Cooper

 

 

My Lotus 32B,good but not smooth enough.

 

 

Stu Brabham,feels good BUT not just not quiet there,not sure why.

 

 

Terry's Brabham and Stewarts Cooper

 

 

Scozz Lotus 25

 

 

 

Max's Lotus and Stubbo's Brabham.

 

The cars are now in transit to Terry at Nelsons Bay.

 

Thank you all for letting us play with your toys.

Hopefully a couple more guys may be inspired to enter from down here, we run these as a club class so no shortage of cars around.

[Slo]

Great pics of interesting builds!

Tried a more rigid chassis this time as I wanted to try to explore some comparisons between the flexi options that I've built into my builds in the past. I think this one is too rigid and harsh in that it reacts to every bunmp and vibration the motor and track etc throw up and it resonates back through the car readily and makes for a difficult and unsettled car to drive. That might be part of it anyway. Its good to get the feedback, proxy races are a good forum for development and improving provided one can get some clues from what the drivers and observers think. I already have some ideas I can look to that might make the #3 and other builds more driver friendly for next time. Development is what I enjoy most about proxies, give it a go, if it doesn't work try incorporating some other idea always striving to move forward on it.....Feedback helps heaps to do that.

Cheers

[Terry]

Thanks for the great pics Phil,

 

A gentle reminder to us hosts that people do like to see pics, and the excellent feedback from drivers is always appreciated.

 

Can I not get too far off topic and ask something about Daves' chassis?

 

I have tried on a number of occasions to build something resembling what Dave has done with varying degrees of satisfaction, frankly my attempts have left me a little under whelmed!

 

One issue has been as to where do I mount the front axle, and what is a "safe" size wire for the main rails? ( I use 47 thou wire )

 

I suppose trial and error is the obvious answer, but I think do I go and put in something which does not work out and start all over again?

 

Probably my hesitancy has resulted in not going too far, but the front axles positioning still worries me as to where do I position it?

 

Is it attached to the side rails or do I mount it on the front brass plate,I sort of think the positioning could negate the flex design.

 

What are your thoughts?

 

Better minds than mine would know, and maybe in an open forum like this others may get some direction as well

[kalbfellp]

Daves chassis is built along the style we were using many years ago for all our cars, long flex bars.

I am not convinced that any flex is required,the kids car is ridged!

I think tyre choice was a major difference on this track. The PG tyres seem to grip better than mine, but let go suddenly.

This tends to make the drivers drive with more caution. Dave car had old Tassie tyres, and was very forgiving.

Stu your car was great Jon real vices,it did not have the initial grip of the other PG tyres.

John Batich seems to be able to prepare Eurethane tyres better than most.

Adelaide will be interesting as the FPR track has proved very high grip in previous years, my cars usually want to roll over there.

Edited May 22, 2017 by kalbfellp

[dangermouse]

Main mods I made this year were a swap from my own urethane tyres to PG tyres and then I filed the scaleauto down a little (feedback last year was it was too deep for Tassie tracks) my main worry now after such a good showing in the first 3 rounds compared to last year is that my car won't be as good on the next tracks as it was last year... oh well that is part of the fun of proxy racing you send your little machine off and hope for the best....

 

maybe the weight of Dave's car has something to do with it as well - is it heavier than other cars? Looks like we need a tip sheet from John on setting up urethane tyres

Edited May 23, 2017 by dangermouse

[Slo]

Tyres aint tires, seems a bit of lottery when it comes to tyres.

DM, OR you might just kick ass. Do you think the changes have helped? I hate that when the likelihood of moving down might be more likely than moving up. Its a healthy and natural response, I think. Good luck!

 

Im as intrigued as others, I think its appropriate relevant for the round specific , someone want to start a general discussion thread?......Dont mean to hijak the thread though but you Tasmanians know stuff..

I know lots of runners have incorporated flex in their chassis builds and Lennys car almost seems to have axle steer, but just focusing on podium spots on Shelmore . From memory and being lucky enough spy the builds at Stubbo's Cape round; Pretty sure Phils has some measure of flex though dont recall the hinge flex . The Grandkids is rigid yet I found it had some kind of softness and smoothness somehow built into it and not harsh at all. Johns car looks very interesting and looks like it has some double chassis arrangement, and some flex without the pivot thing. Then Daves build has the hinge flex chassis with a typical pivot, though old school and looks well forward of the motor more than usual.

How does one determine flex, does it need a pivot point? How does it impact handling? How much flex? How much rigidity? Stubbo has had some success with 1.2mm rails in VRAA, is that 47 thou? But it 's not what Phil calls "long rail" , so is that equivalent to 1.4mm or 1.6mm when the rails are shortened up? Does flex effect tyre wear?

Terry, Im not a club racer so dont really feel an authority to advise as such and by no means a better mind at all, so just saying. I attach my front axle to the guide plate but the rails are also soldered at (adjacent) this point too ( though this years car is soldered full length of guide plate which finishes just in front of motor). Aim for 1.6-1.7mm ground clearance at front, always maximize guide lead length which is 12-12.7mm on the Stubbos Brabhams. Rails are usually soldered full length of motor mount, mostly use 1.6mm rails. Im thinking some flex softens the car a bit so I think I'll tend back to that, but I'm stumped with how the grandkids car is so drivable. Just saying hoping to get others input.

cheers

[Pauls Slots]

Hi all,

Thanks for taking the time to give us all feed back on our little champions.

Building these things is like every thing else in life. Just a little more practice and evolution needed.

 

Great bunch of nicely finished cars.

All the best guys

Paul

[difinity]

While it still has some way to go, and the suspension detail proved very difficult to get right (and still needs work), #6 uses 1.4 rail full length - fitted and glued into the pod.

I tried to use 1mm to get front flex but that was too thin, too much.

Will continue to work through chassis design for this little car more and more like the Int'l 1/32 sprung chassis I used to race - side float and flex and reasonably stiff front to rear to manage bounce. I'll be happy if I get that right by the time Phil's grandkids are old enough to teach me something...

[Terry]

Phil has made the point repeatedly in various posts over recent times that the flex factor is not the answer, the grandkids chassis is a good example, just imagine a field full of cars that could perform like that one!

 

I search for that silver bullit, but there is no silver bullit, it will always come down to the build, there are designs that will be too heavy, too light, and others which are just plain wrong, but after time the realisation dawns upon oneself that its always about the build.

 

For me, I often get into a "rush", cannot wait to get the thing done, I'm running against the clock with a proxy start time looming, or I just get plainly frustrated by something, and instead of walking away and coming back the next morning, I push on and in the end I may end up with a "thats good enough" attitude. Not good.

 

Sometime back I built 2 cars to see what makes these things so different when comparing one against the other, funny thing was that I had 1 car so much better and it came down to doing the little things more methodically, making sure the rails were parallel, uprights were plumb and square and alignment was right, its not coincidence that 1 car will go better than the other.

 

Anyway the search still goes on, I'm just after the same chassis that I managed in 2014, it must be here somewhere!

Edited May 23, 2017 by terry

[shadow_rusty]

I'll be happy if I get that right by the time Phil's grandkids are old enough to teach me something...

Given how well a few of their cars run in the proxies, I think they are already old enough to teach us all something...

 

lol

[kalbfellp]

I think most of the answers come down to patience,Codes spent ages bending the chassis and then tooth pasting the rear bearings to get the rear axle spinning free.The Lola was built over about 6 months.Unlike my chassis that was built one afternoon!

Dave Bantoft is similar,seems to take him for ever to build a car.

IMO anyone intending to race a new car next year should start now, as we all do! LOL.

Edited May 24, 2017 by kalbfellp

[bantoft]

Don't worry guys, my car is illegal as, although I am a modeller I can't be bothered building one with suspension.

Ciao

Dave B

[dangermouse]

We aren't worried we are wanting to borrow ideas....

[bantoft]

We aren't worried we are wanting to borrow ideas....

Go for it, she's pretty old hat!! Just lucky it is relatively easy to drive.

 

 

Dave