Fixing Clearance Issues

[kalbfellp]

I managed to get some time in the workshop today to have a better look at some rally cars and the clearance issues.

 

I selected the Talbot lotus to try and sort out because it had the least clearance and the tyres are close to the gaurds so fitting larger diameter tyres would be hard.

The clearance is less than 1.4mm under the centre of the chassis.

The brass wire is hard to see in my crappy pic!

The chassis was a moulding under the axle that COULD be sanded away.

 

I removed the rear axle and simply filed out the bearing hole 0.5mm lower.

This lowered the axle in the chassis giving plenty of clearance. A little too much!

The brass wire in this pic is 1.6mm

 

Once I was happy with the clearance I simply added a drop of super glue to hold the bearings in place.

 

I had that much clearance that I could sand the tread off the original tyres to make them slick.

I then lubed up the crown gear and ran it for about 10 minutes to bed it in now that it is running as a hypoid and the car is fine.

 

The crown gear on the axle STILL has only 1.2mm clearance but the rest of the chassis clears the rally track very well.

 

I also looked at a Fly Rally Porsche and IMO the best solution with those is to simply sand or file away the bottom of the magnet pocket,as the rest of the chassis has plenty of clearance.

 

Not too sure how these will go with so much weight behind the axle!

[Ember]

Phil let me be the first novice to say THANKYOU!

[miveson]

Great job Phil - I originally thought why would you file down the bearing holders and then it made sense

[kalbfellp]

What seem to be basic to use is new to many! Proxy racing should be about people learning to build cars hopefully better. Now I need help to take better pics!

[356speedster]

Nice

 

Very good method for increasing clearance.

 

I would not worry too much about the ride height just below the axles/gears though, it's the center of the car (between guide and rear axle) that is most likely to bottom out on bumps.

Edited September 1, 2010 by 356speedster

[dangermouse]

Now I need help to take better pics!

 

I will bite

Could be a couple of things - you could be taking the pics too close so your camera's autofocus is struggling or your camera doesn't have autofocus so your eyes are struggling

or lighting isn't right - did you use a flash? try lighting the car and not using a flash then your shutter speed should be faster and the need for a steady hand is not as important....

 

ducks as he leaves the room

 

cheers

DM

 

ps thanks for the tip about adjusting the height

Edited September 1, 2010 by dangermouse

[miveson]

Pics taken with a Canon Powershot A590 IS.

 

You should be able to take a reasonable photo with that camera. Was the camera set to Auto mode (data says it was set to Auto 3 - whatever that means)? How far away was the camera from the subject?

 

You might want to depress the button a little to allow it to auto focus and then fully depress to take the photo. If the flash still isn't going off then you might want to set the Camera into Portrait mode which will allow you to force the flash to fire by pressing the flash button. If your getting up close then the camera has a macro function that may help.

 

My 2 cents worth.....

[Ember]

To add to Mivesons efforts... The macro function is usu ally indicated by a little tulip icon.

 

Low light levels a tripod will help. Detail photos are usually better taken under ambient light rather than flash but it will require a stable camera. If you don't have a tripod, rest the camera on a table or some such.

 

Aren't you glad you cried for help?

[neophytte]

Phil,

 

Finally, something I can help you with!!

 

As Ember suggests, use a tripod, one of these will do the trick: http://www.dealextreme.com/details.dx/sku.2332

 

Next, move the camera away from the subject, and zoom in, rather than moving the camera close.

 

Last, use the 2 second timer so that you are not physically pressing down on the camera as you take the picture, when you are focusing so close, depressing the shutter can sometimes move the camera around, causing it to blur.

 

HTH!!!

 

Richard

[phoeno29]

For those with less skills than Phil, I would add larger diametre tyres to raise the chassis. If they rub on the guard, slip a washer between the chassis and each of the guide posts. Bunnings have a nice selection of silver or brass washers in various thicknesses and hole diametres.

 

They also double up on slopey axles between bushes and rims.

[Ember]

Ok... You mention Bunnings and you're making assumptions!

 

I ask the local hardware stores about small washers, even fibre ones, and tiny screws and I get treated like a freak. Ok... Maybe I am a freak, but that's not the point!

[lenny broke]

Good work Phil

After our little e-mail discussion this week I was going to post something similar tommorrow on my day off, you've saved me the job, cheers

 

Alan

 

another little tip, though not related to clearence is don't use a ninco pro guide as they are a bit long to get the car around some of the tighter hairpin turns. they bind in the slot and deslot the car easier. use the standard sprung guide

Edited September 1, 2010 by lenny broke

[kalbfellp]

Thanks for the photo tips. Lighting on the work bench is crap, trying to hold camera,wire and take a pic!

I try not to use flash, macro was on BUT the lighting is just very poor where I was working and wanted to get this posted ASAP.

Martin: never even thought of adding a spacer, did think of cutting down the mounting post after MY mods to get the body lower!

[Ember]

So a Carrera guide is out then?

[lenny broke]

So a Carrera guide is out then? :minigun:

uhm probably

[gazza]

I realy can't see a problem with the ground "clearance issue" just about all the cars on the list are don't pass

 

As mentioned before even though some cars don't pass the min clearance, they still make it around my track without any problems, most of the problem would seem to be a wheel base issue.

 

Smaller wheel base cars with low clearance are bound to get caught up on anything that isn't completely flat, my stock standard NSR P68 gets around the rally track without any clearance problems

[oldslot]

Ok... You mention Bunnings and you're making assumptions! :minigun:

 

I ask the local hardware stores about small washers, even fibre ones, and tiny screws and I get treated like a freak. Ok... Maybe I am a freak, but that's not the point!

Em if you persist in getting around in that black rubber outfit you are bound to get a few strange looks

[Ember]

It never used to be a problem in Melbourne! :minigun: Ok. I'll ditch the rubber once it stops raining and try again.

[kalbfellp]

Smaller wheel base cars with low clearance are bound to get caught up on anything that isn't completely flat

 

Don't you mean longer wheelbase cars.

 

This is just a guide to help people over come the problem. Last year the same rules applied and eventually all the cars ended up with the correct clearance.

It would be a shame for people to go to all the trouble to go to all the trouble of entering only to find part way thru the event that their car performs porly because it is bottoming out on some ones track.

I know that the cars will ofter GET AROUND the track even if they do bottom out,but it does effect the performance.

[Ben_M]

Thanks for the tip Phil. Had thought that might have been one way to solve the problem, fortunately larger tyres did the trick for me. I do need to lift the front up with some spacers on the guide. Ive been racking my brain to think if I have anything I could use but I don't think I do. Any hints on where to get something I could use?

 

Gazza- I was just wondering, when you say without a problem do you mean they don't bottom out or they do bottom out but I doesn't effect the cars? I know cars on my new track bottom out but it doesn't seem to effect them at all.

[kalbfellp]

Anyone looking for cheap guide spacers Bunnings sell them! They come in the form of irrigation riser tube just need to cut it into thin washers. Some guides do need the hole reamed a little. I has a lenght sitting on the bench always ready.

[gazza]

Smaller wheel base cars with low clearance are bound to get caught up on anything that isn't completely flat

 

Don't you mean longer wheelbase cars.

No .... due to the fact that manufacturers are building cars to "scale" now, cars like the Mini, Cortina and Abarth have the correct diameter wheels for the scale and in doing so the cars sit naturally lower, where as cars like the Mercedes 220 and 300 are a larger car so the wheels are more proportionate to the scale (bigger dia) giving it more ground clearance.

[kalbfellp]

Thanks did not think about the small diameter wheels/tyres. The Alpine and Talbot have very small wheels. But Martins idea of spacers and bigger tyres makes them look like rally cars!

Edited September 3, 2010 by kalbfellp

[teamredracing]

Don't ditch the rubber just yet Em as I think you'll need the snorkle and flippers as well with the rain you guys are copping down there. It could be worse ,we could be rebiulding tracks like our Kiwi cousins. Hope everybody,s ok overthere. I know this may sound silly Phil but if those who are having trouble with clearance problems do all the trueing up of tyres first then do the filing and glueing after .It would be frustrating to do all the mods then go and true your tyres just to find your back at square one again. Sounds funny but to a novice it may happen.

Cheers Craig

[kalbfellp]

trueing up of tyres first

 

Very good point.

 

Please don't glue the bearings in BEFORE checking every thing.