Lunchbox Help Please!

[Grumpy pants]

Righto Gang I need some tips please as I’m struggling and I want to move forward on this model now 😊

1.  My front end droops 🤷‍♂️

I have just new CVA’s with standard oil and springs and the 2 hole disc, but this gives me to much toe in. 

I have now fitted the largest coil collar which has helped a little. 

Would changing the disc to the 1 hole set be a solution?

I have a selection of other Tamiya shock oils should I swap the oil.

The only other option is that I think there is a pair of blue DT02 or 3 springs I could use, but the colour won’t match the rear springs. 

2. Kimborough Servo Saver Slips 🙈

I fitted a nice shiny Kimborough servo Saver but whether I use the smallest spring or the largest spring the horn looks like it is slipping and then not returning to neutral with the fitting that is screwed to the servo.

I am guess the point of the spring is to allow this flexibility to stop the servo being broken- but it should still return to neutral?

3. It Will Not Track Straight 🤦‍♀️ 

The steering rods are millimetre perfect to the instructions.

The servo is dead centre and I have tried adjusting the steering rood and trim, but it will not drive in a straight line- meanders off one side.

Now I know Tamiya have lots of play and I know a  LB doesn’t really spend much time on all 4 wheels, but what am I doing wrong?

[HondaHan]

Hello! 

1) Changing the disk piston for the shock won't really change its stance, rather just how much it damps the spring. I have personally used the Tamiya CVAs and built them exactly as per the instructions and mine seems to sit properly (or as properly a Lunch Box will sit with its very rudimentary front suspension). As for the springs, you could always paint them or be like one of those pro race RCs with different color springs front and back 

2) I use the stock servo saver. It seems to work well but they are sometimes hit or miss. Out of my 5 CW-01 (the Lunch Box chassis) cars, 3 of them  has never had any issues with the servo saver and 2 of them break them constantly, and they are all driven relatively the same way (except one of the non broken ones the hardest out of all of them). Maybe try the stock servo saver again if it's not broken. I would just recommend you threadlock the screw (if your servo horn is metal and you're using a machine thread screw) or liquid school glue the threads (if you're using a plastic horn with a self tapping screw) as it seems common in my experience for it to come off while driving. As for the spring, it is to allow flexibility to stop the servo from being broken but a well designed servo saver should always allow it to return to center (neutral). If the spring can be tightened down in any way, maybe try that.

3) Make sure your shocks are all the same length. Because the Lunch Box has very basic front suspension, if your ride height differs between the two front wheels, it could change their alignment. Also, make sure your servo is truly returning to center. If you are having lose servo saver issues, that could be one of the reasons for it meandering. If all of that checks out and it still wanders, maybe try bracing the front shock mounts on the chassis. Mine tracks straight and its steering links have been bent back into shape with pliers after a crash lol.  

I can post pics of my setup if you'd like. 

I hope any of that helped  The Lunch Box is a fun car and I hope you enjoy it!

[wolfdogstinkus]

Have you considered it may just be the curvature of the Earth? Lol 

I think the best upgrade I did to the lunchbox was put foam in the tyres, bought 2x upholstery foam sheets on eBay and cut to fit. 

After that I fitted monster beetle wheels and stretched the lunchbox tyres on, which reduces the sidewall so the tyres don't wobble around so much.

[wolfdogstinkus]

Spin the fronts and check for wheel/tyre wobble. 

A little toe out on the front should help. 

Seems to handle much better with the bigger monster beetle wheels though.

[HondaHan]

3 minutes ago, wolfdogstinkus said:

Have you considered it may just be the curvature of the Earth? Lol 

I think the best upgrade I did to the lunchbox was put foam in the tyres, bought 2x upholstery foam sheets on eBay and cut to fit. 

After that I fitted monster beetle wheels and stretched the lunchbox tyres on, which reduces the sidewall so the tyres don't wobble around so much.

I might also have to try the upholstery foam sheets for the tires :O

Isn't the Monster Beetle wheels narrower than the Lunch Box wheels? I'd love to run Lunch Box tires on my Blackfoot so very interested in this tid bit

[wolfdogstinkus]

I have 1/8th scale shocks mounted on my boys car.

Link to foams, 

https://www.ebay.co.uk/itm/352161409025

[Grumpy pants]

18 hours ago, HondaHan said:

Hello! 

1) Changing the disk piston for the shock won't really change its stance, rather just how much it damps the spring. I have personally used the Tamiya CVAs and built them exactly as per the instructions and mine seems to sit properly (or as properly a Lunch Box will sit with its very rudimentary front suspension). As for the springs, you could always paint them or be like one of those pro race RCs with different color springs front and back 

2) I use the stock servo saver. It seems to work well but they are sometimes hit or miss. Out of my 5 CW-01 (the Lunch Box chassis) cars, 3 of them  has never had any issues with the servo saver and 2 of them break them constantly, and they are all driven relatively the same way (except one of the non broken ones the hardest out of all of them). Maybe try the stock servo saver again if it's not broken. I would just recommend you threadlock the screw (if your servo horn is metal and you're using a machine thread screw) or liquid school glue the threads (if you're using a plastic horn with a self tapping screw) as it seems common in my experience for it to come off while driving. As for the spring, it is to allow flexibility to stop the servo from being broken but a well designed servo saver should always allow it to return to center (neutral). If the spring can be tightened down in any way, maybe try that.

3) Make sure your shocks are all the same length. Because the Lunch Box has very basic front suspension, if your ride height differs between the two front wheels, it could change their alignment. Also, make sure your servo is truly returning to center. If you are having lose servo saver issues, that could be one of the reasons for it meandering. If all of that checks out and it still wanders, maybe try bracing the front shock mounts on the chassis. Mine tracks straight and its steering links have been bent back into shape with pliers after a crash lol.  

I can post pics of my setup if you'd like. 

I hope any of that helped  The Lunch Box is a fun car and I hope you enjoy it!

Thank you for tips, this one is my 6th LB and a NIB turned up today- I think it is one of the best Tamiya models available 😊, so much fun, so  many possibilities with it and a low entry price kit  makes it an easy choice. 
 

I’m going to try different shock oil tomorrow in just the front shocks and see where that takes me, I have some I can experiment with without spending any money 👍

Funny enough I went back to the bog standard servo horn and it it much, much better. I think that either the Kimborough needs to be screwed down more tightly to grip the spring or maybe the spring isn’t up to it? It was frustrating me yesterday so a tomorrow a bit of trial and error should help. 

Once the those 2 points are covered the tracking will probably be easier to adjust I think. 

 

 

 

[Fabia130vRS]

I would like to see some pictures if possible of what you did.

I have tried to make my own tire inserts of a sponge for car washing... works much better then without, on brushless.

but I am thinking of some new expensive tires with inserts.

 

like this

https://www.ebay.com/itm/184055839415

[HondaHan]

If you wanna go really crazy, Ampro Engineering makes a full double wishbone front and rear suspension for it. The rear independent suspension is technically for the Hornet but it should still work the same since they share transmissions. 

[HondaHan]

8 hours ago, Grumpy pants said:

Thank you for tips, this one is my 6th LB and a NIB turned up today- I think it is one of the best Tamiya models available 😊, so much fun, so  many possibilities with it and a low entry price kit  makes it an easy choice. 

I also think the Lunch Box is the best Tamiyas ever! Cheap, durable, reliable, and easy to fix! The van body also makes it a canvas for cool paint jobs too!

[smirk-racing]

I like Ampro Engineering parts a lot. Alberto's front-end for the lunchbox (double wishbone) is a huge improvement.

I have not tried the hornet independent suspension, but I did put a 4-link kit on the rear. That maintains the solid rear axle but makes it very compliant (gets rid of the hopping and various other problems) so you still get the character of a solid-axle truck but with much better performance.

 

[Grumpy pants]

8 hours ago, smirk-racing said:

I like Ampro Engineering parts a lot. Alberto's front-end for the lunchbox (double wishbone) is a huge improvement.

I have not tried the hornet independent suspension, but I did put a 4-link kit on the rear. That maintains the solid rear axle but makes it very compliant (gets rid of the hopping and various other problems) so you still get the character of a solid-axle truck but with much better performance.

 

I love the look and idea of the Ampro kit a lot- 

1 of these LB is my daughters and never gets used I keep it more for sentimentality and because I have spent quite a lot of time and money on it now.

The new kit is either going to mine to progressively go bonkers with or I might just build it for fun box standard and then gift to my 10 year old nephew- it could go either way 👍

[Grumpy pants]

10 hours ago, HondaHan said:

I also think the Lunch Box is the best Tamiyas ever! Cheap, durable, reliable, and easy to fix! The van body also makes it a canvas for cool paint jobs too!

Bonkers fun, it is the model that makes my brain tick more than any other I have or have had.

I was wrong the one that turned  up yesterday was our 8th and my first new LB kit. 

We only have 2 now, my daughters mystery machine and the new kit.

[wolfdogstinkus]

On 4/11/2020 at 8:09 PM, Fabia130vRS said:

I would like to see some pictures if possible of what you did.

I have tried to make my own tire inserts of a sponge for car washing... works much better then without, on brushless.

but I am thinking of some new expensive tires with inserts.

 

like this

https://www.ebay.com/itm/184055839415

They are nice tyres, I wanted some prolonged but couldn't justify £40 a set when I have 2 boys with lunchboxes so £80 all in. 

I will try and get a pic of a cut foam later but it's nothing Fancy, just a strip about 12inches long, 2inch wide and 1 inch thick. Rolled round inside the tyre, pressed into shape and then fit the wheel.

[Grumpy pants]

So I’ve ironed out the issues over the last few days and it is almost there now-

I replaced the  front shock oil and fitted a 2nd collar which has helped- I may go into replace the 2 front springs at some stage. But it all sits much better now.

I didn’t realise the Kimborough servo saver used all the 3 supplied springs, until I opened the Tamiya hop up equivalent which I had in my spares which I went into to use anyway.

I then reset the servo and the steering rods as per the manual. 

Lessons learnt and I’m a bit wiser for it 👍