Shift in method(s)

[John Thawley]

Last year we built a very fast car... took second at the Council races after losing a tie-breaker. Car ran 3.0xxx's on a 42 BestTrack.

The car was built long wheelbase, 1.5 degree rear cant via bent axles.. 3 wheel rail rider. Graphite. Tuned on glass table. It's a great car and I plan on using it as my baseline once I get a test track.

This year we've got the Block, Proxxon tools and all the capabilities to do it "right"... and run oil.

The rears are drilled with cant. Front with bent axle. Axles treated and oiled per Derby Dad's video.

Here's what I'm experiencing on the first build (no test track - yet).

Rears push out perfectly. Car turns in about 1.5" over 6 ft. (I'm ok with that.)

Where I'm questioning things is, with the bent axle the front wheel tends to roll out of round... yet it spins perfectly round. Just has a little bit of lope... subtle... but there.

With oil, the wheels spin beautifully.... smoother... much quieter... round... real nice. Except, they don't seem to free spin as long as my graphite wheels from last year. Is this normal with oil? My axles are higher polished than last year and I've followed DD's dvd to the letter on the oiling process. Am I putting too much concern into the free spin?

Thanks...

JT

 

[Quicktimederby]

Yep, they will not free spin as long as graphite wheels. It means nothing. The oil process will take getting use to. Don't be discouraged if the first try doesn't get you the results you want.

 

[ZZ Racing]

JT oil prep will not spin the times graphite does doing a spin test so don't worry yourself with that. One thing I check for is sound of the wheel spinning you want no noise coming from the spinning wheel. If you do here something it is usually something in the bore you don't want there. The 1.5 over 6' worries me, I don't think this is enough steer to prevent wobbles unless your running razor wheels. Just my opinion.

 

[Kinser Racing]

Definitely not enough steer, try about 8 inches at six feet . Did you bend the axle per the video? Could be your axle isn't bent properly.

 

[John Thawley]

Definitely not enough steer, try about 8 inches at six feet . Did you bendthe axle per the video? The wheel may still wobble at the angle you're holding it. Try holding it as horizontal as possible and spin it. Then see if you get the wobble. Could be you axle isn't bent properly.

Bent it exactly like the video. It spins fine not installed... in my hand. But on the car, it seems like it has a ever-so-slight limp. The limp is worse if I run positive camber. With negative camber (same as the back wheels) it's not as obvious.

I have it turning in more.... wow... that seems like a lot of leaning on the rail. I didn't run nearly that much last year.

JT

 

[DerbyDad4Hire]

John, sometimes you have to play with the angle of the bend if the wheel is acting up when slow rolling the car.

 

[John Thawley]

John, sometimes you have to play with the angle of the bend if the wheel is acting up when slow rolling the car.

Thanks, DD. I think I may have bent it too far.

 

[Guest]

I tend to run between 3-6 inches in 6ft. You gotta find out what your car likes...but have to have a test track to see other than a tune board.. A turn board is awesome for seeing where your car turns...and after you run it you car retune and take note where your car was the fastest at,.. That way you know.. But from my teat I have never had a car run good with 1-1 1/2 steer.. they always like more...Benji

 

[Guest]

maybe swap out the FDW axle or re-bend it in the opposite direction

 

[Guest]

Corvid, I'd be hesitant to re-bend an axle in the opposite direction that it may potentially weaken it.

 

[Kinser Racing]

Corvid, I'd be hesitant to re-bend an axle in the opposite direction that it may potentially weaken it.

You're right. Not only will it weaken it, but it will most likely break.

P.S Why are we resurrecting zombie threads???

It's most probable that the OP has already solved this. /images/boards/smilies/smile.gif

 

[Guest]

Oops, my bad. Just trying to contribute for all the help I've received. In hindsight it was rather pointless on my part./images/boards/smilies/biggrin.gif

 

[sondo007]

Oops, I guess I was unaware that resurrecting zombie threads was improper netiquette. I assumed the OP was never going to see my reply but figured somebody else may in the future. I for one went through a ton of older threads and gained a lot of knowledge and wanted to repay the favor in some way for all the help I received. I apologize and am thankful I am now aware of the do's and dont's. Hope this doesn't come off as b!tchy- not my intentions. Not sure if my original advice was correct info or not but it made sense to me-peace.

Its All good Corvid, I read through old threads all the time, to find things. Usually if its longer than 3 months someone gets a answer. Most of the time I like clarification of what the answer is. The really good threads are the locked ones that can't be deleted. That means the information was good enough to keep for later. Kinser's got a few of those and 5kids, as well as others too. Widen your search to beyond PRO answers, somethings show up in the most expect categories. Good Luck

 

[Rocket car]

Just don't be afraid of asking corvid. I myself read thousands of posts and then had some idea how to build a car after reading them. I believe my first 150 posts were mostly questions, but all of them were answered. We do have a bunch of great people on this site!!!!!!

 

[Guest]

Thanks for the support- you're all a great bunch of guys.

 

[sondo007]

Just don't be afraid of asking corvid. I myself read thousands of posts and then had some idea how to build a car after reading them. I believe my first 150 posts were mostly questions, but all of them were answered. We do have a bunch of great people on this site!!!!!!

+1 On what Rocket car said. There are a lot of guys who will help out and answer questions.

 

[DEW36]

Just don't be afraid of asking corvid. I myself read thousands of posts and then had some idea how to build a car after reading them. I believe my first 150 posts were mostly questions, but all of them were answered. We do have a bunch of great people on this site!!!!!!

+1 On what Rocket car said. There are a lot of guys who will help out and answer questions.

+1

 

[Kinser Racing]

Sorry Corvid, I wasn't trying to get after you. It's just old threads have most likely been solved. If you have a question ask away. New threads with specific subject lines will always get a better answer. IMHO /images/boards/smilies/smile.gif

 

[pony express]

Hey Thaley, it's possible that what you're seeing in that wobble is too much gap and the wheel hub/ bore has slipped off the main surface of the axle. It might be sitting into the groove. That happens if you switch from graphite to oil and still use a wide gap. The wide gap allows the wheel to come into the body and slips into the groove. That really slows you down. Once you get the friction out of your car you can even run the graphite cars with a tight gap. You can feel it slip off the main shaft by pushing the wheel back and forth against the head of the nail. If there's too much gap you'll feel it slip off. It's a kind of catch. Tighten up the gap and see if the lopping goes away.

 

[Guest]

Sorry Corvid, I wasn't trying to get after you. It's just old threads have most likely been solved. If you have a question ask away. New threads with specific subject lines will always get a better answer. IMHO /images/boards/smilies/smile.gif
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