SpeedDemon 1:10 EP 2wd

[moleman]

Hi
This is a thread on my SpeedDemon project, which is a 1:10 2wd Electric buggy meant for competition.

Just as a bunch of people before me, Ive made a midmounted 2wd buggy, difference is that this concept includes a motor mounted along the length of the chassie and not across(Atomic Carbon S2 and Xfactory X6)

Ive had a few Ideas on laydown shocks and other fancy stuff, but as I thought it through, I realized I first and foremost wanted to race the concept to see if there was anything worth working on.. So I put together a car with conventional upright shocks instead.

I bought a used Kyosho ZX-5 Lazer, and used its complete rearend.
And then I had an old Associated B2 laying around, and the frontend of that car is perfect for this kind of build as it just bolts onto the main chassie(5 screws).

It only took about two afternoons to put the car together.
I have raced two indoor races here in Sweden with it so far.
I won the first race and came forth in the second(mostly due to poor driving).
Havent got the setup perfect yet though, but Im getting there..
As of now Im just getting started making 3D CAD drawings of the concept.

//Morgan
aka moleman

[bloody pom]

Hi there,

where in sweden do you race?

Matt

[moleman]

Hi Matt
I live in a town called Åmål(in the midwest of Sweden), but there are no places to race near here..
So far Ive been to races included in the "Mellansvenska-elbilscupen", or in english: The Electrical car cup of middle Sweden :)

Got any connections to Sweden?

official homepage:
http://mellansvenska-elbilscupen.se/

[Tom3012]

more pics!!! get some detailed pics of the back without electrics :thumbsup:

[moleman]

closeup of slipper and batterytray arrangement:

[annie_himself]

I'm really liking that. Great job. :thumbsup:

[jimmy]

I think I've seen a film about where you live moleman :lol:

Nice work on the car so far!

[moleman]

Thanks guys!
:D

I havent tested the car outdoors yet, I think I'll have to have some kind of undertray first, otherwise say hello stripped gears and electrical meltdown.
The outdoor tracks we got here are usually made from gravel/dirt and isnt the bluegroove type you see in the USA. Dirt gets in everywhere!

But Im really looking forward to seeing how it handles on a loose track with low traction. Indoors on carpet with Taperpin rear tyres it drove through corners like a rocket compared to conventional 2wd's!

[moleman]

Some pics of things to come..

[super__dan]

Are the shocks in the same plane of movement as the wishbones?

[moleman]

Dan, Im not sure I understand what you are asking about..
But this is just a mock-up of parts I had laying around, just to see that there was any chance the shocks would fit laying down like this.

The pivot point of the linkage connected to the shocks is going to be tilted, and have similar angle as the rod thats connected to the lower A-arm, this will insure that the shocks wont get in the way of the rod, if that was what you were asking about..?

Im just about to start drawing this up i 3d cad, so be patient..

[bloody pom]

I am down here in Trollhattan.

It can't be any worse than racing in the hot dust bowl's of Australia.

Matt

[moleman]

Last few days Ive been carving a core in balsawood for a selfdesigned body for the car,
in order to seal as good as possible against dirt and stuff when racing on an outdoor track.

Ive used a 2L Fanta bottle as material. (Thats the biggest PET-bottles we got here in Sweden as far as I know)

Still have some issues with shrink at the ends, but if I just can secure
them, its not far from done. And I think the result is pretty good actually.

Ive painted the body just to see the shape of it easier .
(PINK was the only color I had laying around, bought it in the 90's)

http://rsb.se/arena/attachment.php?attachmentid=4688&d=1205995358

[Garry Driffill]

I really like the look of this car. What does it drive like ? are you still making the one with inboard shocks

Also where do you race :)

[moleman]

It drives really well!
Especially through corners it can carry alot more speed than conventional 2wd's.
Both spectators and compeditors have commented on this at races.

As soon as the body gets finished Ill test drive it outdoors "in the dirt",
really interesting to see how it handles on loose surface.

Yeah, Im still working pn the lay down shock configuration,
a very slow progress so far though :( ..but in the not so far future perhaps ;)

Next indoor race is this weekend(29/3), thats the final of the indoor season,
after that we start racing outdoors.. yeah!

I live in Åmål, Sweden
(we have just started an RC-club, and are currently building an offroad racetrack!)

[moleman]

Just finished the second body.
It turned out OK, Ill use it on the upcoming race this saturday.

Ill put some more effort into painting next time around,
when I have some more time on my hands..

http://rsb.se/arena/attachment.php?attachmentid=4773&d=1206574196

http://rsb.se/arena/attachment.php?attachmentid=4775&d=1206574196

[annie_himself]

Looks great!

[AndyM]

yeh, looks really good.

not too sure on the front wheels though LOL

[moleman]

Whats wrong with the front wheels!?!
..They're vintage "hopups" from back in the day.. (95' or something)
Personally I think they look awesome! :D

These are not my racing tyres btw

[annie_himself]

yeh, looks really good.

not too sure on the front wheels though LOL
I thought those were the standard in Europe. I hardly see dished wheels in the gallery.

[moleman]

Here in Sweden most drive with Dishwheels, only a few with spoked
..for example Jconcept rims, or outdated ones form the 90's :rolleyes:

http://rsb.se/gallery/files/2/20070811_elbuggy_2.jpg

[erkan]

The speeddemon was ace today and took the win in all 3 A-main legs at the finale of Middle Swedish Electric car Cup. :thumbsup:

[Alfonzo]

Well done. You ought to be proud - it's nice to see something different.

[annie_himself]

Great news! Congratulations! Did you race mod?

[erkan]

yeah he did.. its the only class over here :)

[moleman]

Yeah, I somehow managed to win this one!
Never really got the car setup perfectly, had some trouble with tractionroll in some corners when pushing it too hard,
and also Im pretty sure I had the slowest car down the straight(ran a 12*1 Peak Racing David Spashett motor with 5cells).. other from that the car worked great!

The new body and my Ko-propo 2413 servo made the car almost too light (with 5cell battery),
had to put an 10g weight on it! =1480g tot, It was about 50g lighter than a B4.

Erkan had the quickest laptime of the day though, bout 0.3sec faster than my best lap.
If you only had ran a little more consistent yould be the one to take top honors!!

[moleman]

A better picture of the car with its new body:
http://rsb.se/gallery/files/3/2/4/4/080330_speeddemon002.jpg

[annie_himself]

It looks amazing, just the front tower looks so...untrendy.

[moleman]

:D Yeah isnt it cool!?! hehe
(I dont follow no trends, I do what I feel like..)

Ive thought about making a new chassis with an RB5 front end, but I dont know..
It feels good to pay tribute to the B2, as it was the first car I had that I felt
I could be as quick as Anybody at the tracks.. and maybe its part of what makes this car fast as well..?

[Tom3012]

if it ain't broke, don't fix it!

Great work, looks great!!:thumbsup:

[moleman]

Thanks Tom,
Yeah, I think Ill save that money and put it on new motor and batteries.
Ill put some more effort into making progress on the laydown shock concept as well.. going nowhere recently :(

But in my head the design is almost finished!
Its "just" a matter of getting it all into place and finding/manufacturing parts that fit!

[Tom3012]

Its "just" a matter of getting it all into place and finding/manufacturing parts that fit!

i like the "just" :lol:

[moleman]

Exactly! :bored:

Yesterday I did some CAD-drawing in Pro-E.
Its really tricky to get it all to fit, BUT It'll look so damn sweet if it works!!

If I have some more time this afternoon, Ill post a sneakpeak of the progress here soon..

[gaza121]

How the heck did you make such a nice body using a fanta bottle?
Can you tell me the process?:)
top work nice to see radical designs beating everything~!

G

[Lee]

Gaz,

Its just about making a mould from balsa or a special clay, depends how much you want to spend, and getting a heat gun to soften the plastic then mould it over the mould, northy has done it too, but he uses Oasis, i think its slightly more refreshing:thumbsup:

http://www.oople.com/rc/photos/kidderminsternational2007/kid120507/imagepages/NO5E1508.html

[moleman]

Gaza; If you look earlier in the thread, youll see that I have posted
a picture of the balsa"core" inside a 2L Fanta bottle.

The bottle has been cut open in the bottom to make it possible to slide the core inside.
I use a heatgun to warm the material, the PET bottle then tries to get back to its original shape
(which is a really small tube) and thereby gets a snugg fit to the core!

But it makes a "tent" over any concave shapes, as the material gets as "short" as possible..

[moleman]

A photo from the race in Falun.
The cars are lined up for a qualifying heat.

Its pretty slim compared to the Associated, Losi and Kyosho cars..

http://rsb.se/gallery/files/2/5/6/2/dsc00164.jpg

[moleman]

Hi
The progress of the laydown suspension isnt coming along as I would've wanted..
I may have to put it on hold for a while.
Im thinking of making a new chassis including a RB5 front end instead,
not as innovative as lay downs, but would be pretty sweet anyhow.

Tomorrow is the first outdoor race for the season, in Örebro, Sweden.
There has litterally been an explotion of entries for this race, as over 70 people have signed up!!
(compared to last year; about 20-30people/race)

I have done some testing with the car on the local OR-track here i Åmål, and the conclution is: SLIPPERY.
When accelerating you have to be super gentle on the gas, otherwise it gets uncontrollable..
Although, it goes very smooth over bumps(the local track is VERY bumpy) and it jumps very good!

Well, there are about 40people racing 2wd on tomorrows race,
Ill be lucky if I reach the B-finals!

[moleman]

Race summary:
Couldnt get any traction on the rear wheels!

I attached a 140g weight behind the rear shocktower,
I found the car almost undrivable without it.

My best laptime was low 24 sec, compared to the fastest drivers that drove high 22's.
I was driving at the edge to uncontrollable just to keep up..
and because of that many mistakes were made.

Qualified at 19th place, 9th in the B-Finals.

Due to bad luck in both B-finals I ended up at 10th place.
20th place overall out of 38 racers.

I guess its not all that bad, but my conclution is that the car doesnt seem
to have enough traction on slippery tracks to be competative.

[sparrow.2]

As sad as it sounds midmotor cars go fantastically when you have lots of grip, carry a lot of speed round corners and jump very nicely and and and...

Once it gets slippy though they turn pretty much undriveable. I have seen this at a couple of races now with homebuilt and X-Factory cars. They go really well on carpet or bluegroove but as soon as it gets dusty they really struggle to get the power down out of corners.

Your car does look really nice though :) Just put it away for the next winter indoors season...

[moleman]

As sad as it sounds midmotor cars go fantastically when you have lots of grip, carry a lot of speed round corners and jump very nicely and and and...

Once it gets slippy though they turn pretty much undriveable. I have seen this at a couple of races now with homebuilt and X-Factory cars. They go really well on carpet or bluegroove but as soon as it gets dusty they really struggle to get the power down out of corners.

Your car does look really nice though :) Just put it away for the next winter indoors season...

Yeah, the result was pretty much expected. But I really hoped it would work.. but now Ive "learnt it the hard way".
Im now looking forward to the Swedish Nationals at the 16th of August instead, as its held at an astro-turf track
and everybody says it has lots of grip. Think/hope my car will be ace there!

[bloody pom]

Where are the nationals held?

[moleman]

The Swedish Nationals are held at the Skarpnäck raceway in Stockholm.
The track also known as "Green Hill".

Link to youtube-video of the track:
http://www.youtube.com/watch?v=aPyE8mRzxmE

[moleman]

Some pictures of the conceptcar with the RB5 front mounted.
Just mounted with one screw, have to make a new chassis to make it fit..

http://rsb.se/arena/attachment.php?attachmentid=6386&d=1214418473

http://rsb.se/arena/attachment.php?attachmentid=6385&d=1214418473

This weekend there is a race in my birthtown, Falun, I will have a go with the RB5 to see if its any good(only tested it in my appartment).

[warped]

Moleman.

What wheelbase are you running?

Because if you lengthen the wheelbase, by moving the front end forward, it should help by putting more weight on the rear wheels.

If the bits ever turn up for my zx5 based 2wd, am probably going to go for a wheelbase of about 280mm.

That's about 10mm longer than most 2wd cars.


The other thing that may really help your car is if you can run lipos. - You can then put lots of lead wherever it's needed, and get round the lack of rear weight problem that way.

[moleman]

I dont know exactly how long the wheelbase is, but its pretty much the same as the RB5 or the B2 for that matter. I can check it if you want.

As far as wheights go, if you read earlier in the tread you'll see that I did wheight the rearend quite a bit(140g) at the race in Örebro but still struggled with lack of rear grip.

I have compared my concept car to both the associated B2 and Kyosho RB5 and the conclution Ive made is that its soo far off it isnt worth the hassle.

On high traction tracks, its a totally different story!!
In the corners, thats where this kind of layout excells..

[cstroh]

wow that body looks great did you make it? if so how?

[moleman]

wow that body looks great did you make it? if so how?

Yes, Ive made it..

"If you look earlier in the thread, youll see that I have posted
a picture of the balsa"core" inside a 2L Fanta bottle.

The bottle has been cut open in the bottom to make it possible to slide the core inside.
I use a heatgun to warm the material, the PET bottle then tries to get back to its original shape
(which is a really small tube) and thereby gets a snugg fit to the core!

But it makes a "tent" over any concave shapes, as the material gets as "short" as possible.."

I bought some tools and stuff yesterday, so hopefully this evening I'll start with the 2nd gen. SD! ..With the RB5 front end.

[charles08]

Hi, this concept is really cool !!!
You should post some videos. I love the way it looks.
Does it handle better with Rb5 front than the B3 front ??
Congrats ! :thumbsup:

[moleman]

Hi, Thanks mate!
I havnt completed the build of the new chassis yet, just finished the main chassis last night.
Must have something that makes the chassis flex less in the lenght of the chassis.
And also someway to secure the batteries.. I've got some ideas, but not sure if they will work.

My "high-tech" Mech corner :thumbsup: ..Main chassis almost finished:
http://rsb.se/gallery/files/3/2/4/4/ssc_0074.jpg

Front and rearend mounted to the new main chassis: http://rsb.se/gallery/files/3/2/4/4/ssc_0075.jpg

[mr. ed]

hehe, been reading through all the post and your project has given me a push and drag at the same time.
I have a jr-x2 chassis i wont to combine with a yz-10 rear end and ultima based front. The multitude of large jumps being the main reason tog midmotor, but on the other end , the SLIPPERY part of the concept is far less attracting for the track nearest to me.

Hope you 'll do well at that major event, good luck

[moleman]

I've also got an old YZ-10 lying around!!

Yeah, the conclution I've made is that it jumps really well, and as said earlier, brilliant cornering on high traction tracks.

Best you could do with a midmounted car is try to get the motor running in the opposite direction of the rear wheels, you'll gain some traction by doing that. But in order to do that you'd need som kind of gear tranny..

EDIT: Just realized thats what you'd get if you use a YZ-10 belt-tranny! (too early in the morning)

Good luck!

[mr. ed]

...

EDIT: Just realized thats what you'd get if you use a YZ-10 belt-tranny! (too early in the morning)

Good luck!

I think you edited that in while I was trying to post my reply ;)

What would be the best option for the front kick-up? 10 degrees like a 4wd or more; like a 2wd?

[moleman]

I believe that kickup more like conventional 2wd's would be best, as you dont have drive on the front wheels.

[moleman]

Here's a shot of the new car, finally completed and ready for this weekends nationals in Stockholm.
Next to it the remains of the old one.

http://rsb.se/gallery/files/3/2/4/4/ssc_0035.jpg

I'll post some more pictures after the weekend..

[moleman]

Some really nice photos from the Swedish Nationals can be found here:
http://www.aobild.se/index.php/v/Motorsport/RC/20080816/?option=com_gallery2&Itemid=26&g2_page=3

http://www.sevenofnine.se/rc/rm2008/

http://s265.photobucket.com/albums/ii236/Foppa323/RM%202008/2WD/
http://s265.photobucket.com/albums/ii236/Foppa323/RM%202008/4WD/

[moleman]

In short: The car performed really well! The driver, not so..
Only managed to make one half-decent qualifying round.
The rest Id rather forget. Finished in 12th place.

[moleman]

Here's a short clip from the start of the second B-finals, in slowmotion..
(Shot by Mr.Pink)

You can see my car in black, after getting run into over the first jump,
I luckily landed on the wheels and after a few bobbles by the leading car
I managed to take the win of this heat, finishing 12th overall.

http://www.youtube.com/watch?v=AJN8qwMm9gc

This track is awesome!

[moleman]

Finally, here are some pics of the finished car:

http://rsb.se/gallery/files/3/2/4/4/ssc_0064.jpg


http://rsb.se/gallery/files/3/2/4/4/ssc_0063.jpg


http://rsb.se/gallery/files/3/2/4/4/ssc_0062.jpg


http://rsb.se/gallery/files/3/2/4/4/ssc_0061.jpg


http://rsb.se/gallery/files/3/2/4/4/ssc_0060.jpg

[mr. ed]

probably sounds lame, but I reallly want to say again: verry verry impressed with your work!

[moleman]

probably sounds lame, but I reallly want to say again: verry verry impressed with your work!

Thanks alot Mr.ed! :)

[charles08]

Hi, i loved the video in slow motion that was kinda funny...
We don't realize how painfull it is for the cars i guess.
I've seen your car on the video and the pictures....What can i say...it looks like it kick ass :woot:!!!!
I was wondering what is that long turnbuckle from the rear part that pass up the batteries and fixed in front behind the esc?? It seems to be adjustable, is it ??Nice car mate.Great work.:thumbsup:

[moleman]

Hi, i loved the video in slow motion that was kinda funny...
We don't realize how painfull it is for the cars i guess.
I've seen your car on the video and the pictures....What can i say...it looks like it kick ass :woot:!!!!
I was wondering what is that long turnbuckle from the rear part that pass up the batteries and fixed in front behind the esc?? It seems to be adjustable, is it ??Nice car mate.Great work.:thumbsup:

Thanks m8!
The turnbuckle is adjustable, but Ive only adjusted it so that the main chassis sit flat.
Its working as a topdeck, but only stiffens the chassis in the length of the car, thus allowing alot of torsionflex.
This is a test to see if an offroad car can gain anything from having anything other than a stiff chassis
(most buggy chassis are very stiff).
I belive it gives the car a little more side grip when cornering(doesnt lift inside rearwheel as much)
and makes the car more forgiving and easier to setup.
Though, in total I think it may be easier to drive but may also be a bit slower..
will do some more testing on this when we start indoor practice.


Here are some more videos from the race, in full pace this time:
http://www.youtube.com/profile_videos?user=johansevenofnine (http://www.youtube.com/profile_videos?user=johansevenofnine)
Im running in the 2wd B-finals, car no.4