19 replies to this topic

[LiqTenExp]

Hey,

 

Can you recommend the right thickness braids for a box stock GP12 Koford wing car? I replaced them with a shortened set that I'd normally use on a GTP the car would bounce it's way out of the slot or just not be able to move w/o jittering/jittering. I tried a thinner set and it was better. Track runs around 0.020" under flush on the braids.

 

I also have issues with it chattering out of turns. I'm running on a modified hill climb that is prepared with glue for our weekly GTP race. I assume I need to run harder tires? My next step up in hardness will be a wonder medium tire, a set of wonder soft I tried had similar results to the factory tires. Any recommendation here would be appreciated.

 

I haven't run a wing car in over 20 years... could use a hand lol.

[Pablo]

Brad, try posting this in the wing car section, you may get more "traction" that way. I haven't raced my wing car in 20 years, either.

 

But I do know the fundamentals of braid and front ride height. Changing flag spacers and/or changing to a thicker or thinner braid are options.

As well as shortening the braid little by little to lower the front.

 

Depends on the track, the clearance rules, the car, the scum on the track, etc.

 

As far as tires, the general rule is use the hardest rubber you can get enough traction with. Lap times are the only truth, everything else is theory.

 

Braids are available in thicknesses anywhere from .022-ish to >.032-ish.

[mreibman]

Ok, it just happens that I race group12 wing cars. I'm not the best or fastest, but placed 6th in OMB at the barn burner recently.

My take is that braids do not cause corner chattering.

For braids, look to a 408 strand brand that you like. A lot of locals use Prime and Red Fox. I use Paw and have good results with it. I tried SCB, but had plenty of issues... It just didn't work for me. If you're using the cheapest braid available, try something better.

Depending on the track conditions, try cutting total length down to between 25 and 30 mm.

BRUSH YOUR BRAIDS. Can't stress this enough.

Spacers for the guide... This is where you adjust your ride height. Start with .005 Teflon above and below the chassis (between the guide and the chassis, and between the chassis and the nut). Adjust with more between guide and chassis for braid depth.

Now, chatter in the corners is generally the result of a number of issues including:
- bent rims
- broken solder joint on motor
- axle bearing issues including worn out and not soldered to chassis (out of the box, I don't think they solder them in on the RTR cars)
- bent axle
- broken chassis - check pillow blocks and solder joints
- bent chassis
- not enough downforce (body/wing issue, car going to slow)

That's a lot of stuff, right? I bet there's more, too.

[Rob Voska]

I believe wing cars don't slam the front on teh track like scale cars.  

[MSwiss]

IMO, thickness of braid isn't your issue.

It's length and temper.

The first tine I spotted shorter braid on a slot car was about 1995, on a Martin Gramann car.

It's become mainstream since then, but can be overdone, especially these days with lighter cars.

On my King, with Group F cars, if the braid is cut too short, the car doesn't take off from a stop as easy, and is trickier to drive out of the Lead-on, on Purple and Black.(probably due to lever arm length related contact)

I don't think you want full length, but I wouldn't shorten it more than a 1/16" to start.

Also, too stiff will probably hurt you.

I like JK Stiffer, which really isn't stiff.

It's just stiffer than their soft braid.

[Bill Seitz]

Chattering in the corners is likely due to the tires being too soft. If the track has a normal amount of glue and rubber buildup, you'll want at least a hard tire and most likely one that's narrowed. Try the Koford H or X.

[gotboostedvr6]

First and foremost post pics of your car. If paying pics is a problem message me your email and Ill post them for you.

Take several good clear close up pic of everything.

[LiqTenExp]

Some pictures with body off. Note there is 1 piece of lead missing in this photo, I'm aware (all of it was put on temporarily as I was testing, it isn't as neat as I would have for a final install). I started adding lead to the front based on the suggestions above and it starts to help but really doesn't fully prevent the issue. The car just keeps lifting the front up and disconnecting the braids. 

 

I did put the chassis on tech block and found it was marginally bent up from motor pod forward, it is now flat.

 

I've tried 408 and 458 style braid and didn't help. I'm on 408 style braid along with a cut down guide to drop the front of the car. Initially the car was slopped up towards the front, I'm sure that wasn't helping. Now it is about even or slightly down. 

 

I've gone from stock fish to wonder soft, wonder medium, and now wonder hard tires. The hard and medium work equally on this prepped track surface and better than wonder soft or stock fish.

 

After the braid, tires, chassis, and weight it is kinda ok. Any other suggestions?

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[MSwiss]

Is this just at take off, or in the course of a lap?

[LiqTenExp]

Is this just at take off, or in the course of a lap?

Mostly at take off, once moving it is usually ok except when pushing it hard through tight turns, sounds like it might be happening there too. At takeoff it may bounce endlessly and never make any speed.

[MSwiss]

What type of controller do you use?

[LiqTenExp]

What type of controller do you use?

 

Carsteen CS-4

[MSwiss]

With my wing racers that have trouble popping at take off, I always tell them the same, semi-obvious, thing.

Adjust controller your controller for smooth take offs.

You can always adapt your driving style while the car is moving.

Your car should start moving slowly once you hit the first few bands.

If you aren't getting any movement from the car, until you are a 1/3 or 1/2 down the bands, chances are you are going to get too abrupt of a take-off and pop or stutter and pop.

[LiqTenExp]

What I've noticed (slow-mo video) is each time the motor steps to a new position relative to the magnets it will shutter at that rate, makes it hard to take off slow even.

 

How close should the front of the car be to the track? My "flexi" style cars w/o wheels touch in the turns for example, looking at this chassis I don't believe that is ever expected to be the case.

 

With my wing racers that have trouble popping at take off, I always tell them the same, semi-obvious, thing.

Adjust controller your controller for smooth take offs.

You can always adapt your driving style while the car is moving.

Your car should start moving slowly once you hit the first few bands.

If you aren't getting any movement from the car, until you are a 1/3 or 1/2 down the bands, chances are you are going to get too abrupt of a take-off and pop or stutter and pop.

[MSwiss]

You need to post the video.

A slight chance is you have a problem with your controller.

Have you tried your car with someone else's controller?

[LiqTenExp]

Controller is fine, works with all other cars. My other controllers do the same, it is the car.

 

You need to post the video.

A slight chance is you have a problem with your controller.

Have you tried your car with someone else's controller?

[studentdriver]

Controller is fine, works with all other cars. My other controllers do the same, it is the car.

 

 

I was having the same issues. For me it was tires and running some sort of higher amount of choke. I'm talking like whatever scale of choke your controller has to turning up to at least half way or more. (well, if your choke isn't linear then half might be low or high, just depends on scale of choke).

 

1) I went with medium wonder

2) I have to crank up the traction control on my difalco.. I guess some people have better control and can not power on too hard but not me.. choke seems to force a limit on me.

 

I heard potentially rounding the edges of tires as well but I didn't have to do that. What's interesting is I end up running a bit of glue on the tires then too (even though too much traction was an issue).. the glue seems to even things out for me (also my track doesn't do any weekly prep work at all so that's on me). Why? when I would go complete power on (in straights) it would spin the tires.. with a glue it would seem to help in certain spots. It is a battle of too much in some spots and not enough in others.

 

Mike

[studentdriver]

 

I was having the same issues. For me it was tires and running some sort of higher amount of choke. I'm talking like whatever scale of choke your controller has to turning up to at least half way or more. (well, if your choke isn't linear then half might be low or high, just depends on scale of choke).

 

1) I went with medium wonder

2) I have to crank up the traction control on my difalco.. I guess some people have better control and can not power on too hard but not me.. choke seems to force a limit on me.

 

I heard potentially rounding the edges of tires as well but I didn't have to do that. What's interesting is I end up running a bit of glue on the tires then too (even though too much traction was an issue).. the glue seems to even things out for me (also my track doesn't do any weekly prep work at all so that's on me). Why? when I would go complete power on (in straights) it would spin the tires.. with a glue it would seem to help in certain spots. It is a battle of too much in some spots and not enough in others.

 

Mike

 

Per a recommendation I decided to revisit the tire tweek from from Trinity. Apply to tires, let soak for 20-30 mins and then wipe of the excess.. Man, it was awesome for my wings cars. So consider my suggestion for using glue "old school" and maybe try the trinity tire tweek. I still used a decent amount of choke to make driving a bit easier in my old age Can't describe the grip I had around the entire track and no messy glue to deal with.

 

Mike

[Dave_12]

Which Koford Group 12 wing car chassis is that ?

[Bill Seitz]

Wing cars have gotten so light that lifting the nose on a standing start is common. Adding weight to the front will help this, but added weight will likely make the car uncompetitive to cars that have no added weight. Too much bite and the wrong gear ratio can aggravate the problem. A longer chassis (guide to rear axle) also helps. As Mike Swiss has noted, mushing the controller will usually get the car off the start. This means the "mush" buttom if your controller has one or turning the sensitivity lower - or using Traction Control or Choke which does the same thing - to get the car started, and then turning the sensitivity back up once the car is rolling. Power needs to be applied slowly and gradually, not a sudden starting burst. There are multiple techniques with the controller to accomplish this. Usually there's enough momentum and aero downforce once the car is rolling that lifting the front is no longer a problem on most tracks once the car is moving.

 

The only impact braid will have is if it's not laying flat against the bottom of the guide. Any springiness in the braid will add to lifting the nose. When the guide is set in the slot, the pickup braid should not be lifting the guide. I've used plain old 408 braid full-length and pressed flat for years which seems to work fine.

 

For Dave Rees: Koford and others don't refer to chassis as G12 now, they're "Boxstock". The latest 530-series chassis have no front pans and will be more prone to nose-popping. The 746-series I believe still has the pans (nose weight). Note: Use "Boxstock" not "C12". The "Boxstock" chassis fits C-cans and is a bit heavier and longer. The "C12" chassis is for cobalt motors and very light and short (often aluminum).