[WIP] Pajero Pinin

[piterx]

Hi there guys!

Last year in this period i was developing my first sleeplessness car: the Fulvia

Now, as i have an incoming exposition with the shop wich is sponsoring me, i'd like to build something more complex...here's the plan:

Pajero Pinin!

It's been designed by Pininfarina in 1998 and it's probably one of the last offroaders made by Mitsubishi before the invasion of SUVs...and it's probably the reason why i like so much offroad vehicles as it's my actual car :P

Im gonna scale it to the 42000 wheels as they're so similar in proportions to the real ones and they've never been used for an offroader by the community :)

This is the list of features that i'd like to have:

5+R sequential gearbox

Auto clutch (the same used in the Fulvia)

AWD with lockable differential in the middle (or without differential at all)

Rear lockable differential

Mac Pherson geometry (im gonna use the Nicjasno perfect one, trying adding the next feature)

Disc brakes or a braking system in general

Rear live axle

Lights

Working steering wheel

Openable doors, hood and trunk

Enough stuff to lose sleep as the deadline will be the 18 of march...

I have a month...

will i ever make it? hopefully yes XD

i hope you'll like it :)

[Junpei]

Wow! That's ambitious. Although aren't 42000's tyres like twice as wide as the ones on the real vehicle?

Might want to check this out:

TLH

[Technyk32231]

Those wheels have been used.

http://www.eurobricks.com/forum/index.php?showtopic=87903&view=&hl=&fromsearch=1

[piterx]

Wow! That's ambitious. Although aren't 42000's tyres like twice as wide as the ones on the real vehicle?

Might want to check this out:

TLH

not really they're just a little bit wider than the real ones :)

yeah i might do something like that for the front axle...i need to improve that design with disc brakes...

now it's mainly time to make the gearbox...the most annoying part eheh

Those wheels have been used.

http://www.eurobrick...l=&fromsearch=1

my bad :)

[unimog123]

Wow! That is a tight schedule. I think if you find that you don't have enough time, everyone would still want you to finish this no matter how long it takes. Good Luck!

Edited February 18, 2014 by unimog123

[skriblez]

Ambitious and awesome sounding!

[rm8]

Good choice of tires. They can be changed to 81 mm offroad balloons from 42005 to make Pinin look more angry;)

Waiting for first pics;)

May the force be with you, PiterX!

Edited February 18, 2014 by rm8

[piterx]

ahah thanks egor xD

the dark side led me to this gearbox here

quite simple...i took inspiration from this one wich is great http://www.mocpages.com/moc.php/248140

im trying to simplify it and make it the more strong i can in order for it to be reliable...

basically all the tan gears, even if it doesn't seem, work independently from each other

it's just a 4 gearbox....i'll manage to add the R gear later

at the moment you're watching it upside down as the axle on top will be connected to the differential once i'll place it inside the model

there will be a sliding gear wich will activate the tan gears, so the gearbox is actually a linear one

a single actuator would work great to switch gear but i want something faster than that, i'll probably use a servo motor to switch the gear

but that's a problem that im gonna solve later....

hope you like it ;)

Edited February 19, 2014 by piterx

[unimog123]

Looks good! Although if you have to add another gear plus a reverse gear it will end up being quite large. This could be a problem, but I'm sure you can figure it out. Can't wait for more!

[piterx]

no i will add only the reverse wich is gonna make it just one stud longer...

there will be no 5th gear as the combinations you can have with those gears are only 4 :P

edit:

added the reverse....1 stud longer

now all i have to do is making it in the stronger way i can....everything needs to be braced firmly :)

for those who wanna try building it:

in these pictures the 1st gear and the 2nd are inverted :P

i've managed to fix it already by inverting the gears on the right of the picture

Edited February 19, 2014 by piterx

[Hrafn]

Very nice! I look forward to seeing the completed version.

[unimog123]

Oh, well in that case it should be fine.

[Hrafn]

The reverse gear can be switched to a 5th gear. The one downside is that it's not much of a change from the adjacent gear; for a smooth gear ratio curve you'd want a further 20:16 gearing or something similar.

Rather than a dedicated reverse gear - which could be slow to switch to if you're on the fastest gear - it might make sense to use a variant of Sariel's direction sensitive gearbox. Instead of having the output rotate in the same direction no matter the motor input, you can use the ratchet to select between reverse (which goes through a dedicated gear train to gear down the motor) or forward (which then goes through whatever gearbox you're using, in this case a 5-speed). That way you get 5+R but the ability to switch into reverse quickly. If you put a spring on the ratchet that tends to return it to a neutral (disengaged) position when the motor is off, you've also got a clutch built in. As soon as you stop driving the motor, the clutch disengages and you can (theoretically) more smoothly shift gears. EDIT: you'll need brakes if you implement this, but you already did so in the Fulvia.

Of course, actually putting all this together is the tricky bit. In particular I think it'll be an interesting challenge to create a gear selection mechanism that is fast, accurate, and strong.

Edited February 19, 2014 by Hrafn

[piterx]

yeah i know what you mean, the main thing that led me to 4+R is that these are the combinations possible with those 4 gears...

and, about the reverse, i don't think i will ever use it immediately after the 4th :P

the only thing i need now is making a mechanism that converts a 90° rotation of the servo into a 1 stud movement...

i'll figure it out tomorrow maybe :)

[Technyk32231]

Try something like this: lol , where the two "l"s are on top of a beam, and the "o" is a bush on a crank mounted to the servo. Sorry I can't put an image, I'll see if I can find one someone else did.

[Doc_Brown]

yeah i know what you mean, the main thing that led me to 4+R is that these are the combinations possible with those 4 gears...

and, about the reverse, i don't think i will ever use it immediately after the 4th :P

the only thing i need now is making a mechanism that converts a 90° rotation of the servo into a 1 stud movement...

i'll figure it out tomorrow maybe :)

Think I had an idea for that, let me see, BRB. I can take pics now! hahahahha

This is looking like a very interesting project for you man, as its a larger scale than your other mocs.

Very interested to see how it come out.

[Technyk32231]

I found out that the steering in set 8066 uses the exact same concept I was trying to suggest.

[piterx]

proof of concept :)

it works way better than i actually expected....i thought the main shaft could skip gears but it's very strong!

i just need to reinforce the external gears because they can skip easily in the way they're made now...

now i just need the activation mechanism :)

i hope you'll like it!

[timslegos]

Great Gearbox! Do you think the gears will bind when trying to change gears since they are not bevel gears?

tim

[piterx]

thank you :)

no i don't think they will be forced as long the shift will be fast ...and anyway, there will be a clutch inbetween the gearbox and the motor

at the moment im reinforcing the reverse gear as it's the only one that doesn't make the motor stall...

[unimog123]

Nice job! I can't wait to see your activation mechanism.

[piterx]

Before going crazy thinking a way to build the activation mechanism, i thought it was time to test the gearbox.

You can see it has the same configuration that the fulvia had except for the fact that i geared the L motors down to have a better torque...

I might use one or two XL motors at the end...i'm not sure yet

The nice thing is that the gearbox has such a small friction, that if you push it, it doesn't make any resistance....seems like there's no gearbox at all wich is good :D

I've used the perfect Nicjasno's mac pherson structure, hope he won't mind :P It's just impossible doing it better than that!

For proportions fidelity i can't add disc brakes to the front wheels...so i have to decide if it's better having a braking system directly on the main shaft or on the rear axle...

To be sincere the wheels are 1 stud too wide...but that's not going to affect the final look that much

[rm8]

What about these wheels?

They are about 80 mm and narrower than your wheels

[piterx]

yeah i know those wheels but i don't have them and mainly they don't look as the real ones :P

in the meanwhile i had to change the gearbox because the reverse was skipping...so it became a 4+N+R....and now the grinding problem is finally solved lol

[unimog123]

Nice job! Are you going to use an M motor for the brakes, like you did in the Fulvia, or are you going to use a Servo motor instead?