Instead of Bending Axle Can I drill DFW at an angle/Cant to Rail Ride?

[1reason]

Anyone know what the best angle(s) or method to drill the DFW axle hole to avoid having to bend an axle?

I thought I read somewhere that if drilled at X amount of angle (or whatever the term) I could avoid the dreaded axle bend.

For the rear wheels, my understanding is I want to have a 3 degree cant, but I thought I read I want to also have them slightly "V" with the top of the V towards the front of the car in relation to the rear wheel direction??

 

[OPARENNEN]

DD4H has a predrilled block that is quite good. However, IMO a serious racer should use the bent wheel on the DFW. You have much more flexibility to fine tune your car during testing both on a track as well as on the Test Board. E.g., what I do is set my car steer initially at 12 inches over 8 feet. Run a couple of tests on a track, then increase/decrease the DFW until you get the best time. I totally ignore the COM.

re. rear wheels. 3 degree cant is good. But no toe-in or toe-out on the rears. Use the Silver Bullet and make them absolutely parallel. For me, I don't want any more than 1/5000 difference between the axle and wheel bore (I hate sloppy wheels). Use a caliper (on the axle) and several pin gauges from 3000 up to 7000 (on the wheel bore). Usually that means I start with .092 axles and during the polling process,carefully take meat of the axle until it reaches 5000th with the wheel bore.

 

[Kinser Racing]

Don't be afraid to bend the axle, it's really quite easy. IMO it's much harder trying to get the right degree drilled into the block of wood then bending the axle and tuning it that way.

 

[1reason]

DD4H has a predrilled block that is quite good. However, IMO a serious racer should use the bent wheel on the DFW. You have much more flexibility to fine tune your car during testing both on a track as well as on the Test Board. E.g., what I do is set my car steer initially at 12 inches over 8 feet. Run a couple of tests on a track, then increase/decrease the DFW until you get the best time. I totally ignore the COM.

re. rear wheels. 3 degree cant is good. But no toe-in or toe-out on the rears. Use the Silver Bullet and make them absolutely parallel. For me, I don't want any more than 1/5000 difference between the axle and wheel bore (I hate sloppy wheels). Use a caliper (on the axle) and several pin gauges from 3000 up to 7000 (on the wheel bore). Usually that means I start with .092 axles and during the polling process,carefully take meat of the axle until it reaches 5000th with the wheel bore.

"take meat of the axle until it reaches 5000th with the wheel bore."

Thank you, I'm not sure what that means though?

 

[1reason]

Don't be afraid to bend the axle, it's really quite easy. IMO it's much harder trying to get the right degree drilled into the block of wood then bending the axle and tuning it that way.

Thanks, that's what I will do then.

 

[GravityX]

Let me try to straighten this out for you 1reason.

I think what Opa was saying is, when using a .092" axle, he would use some pins gauges from .093"- .097" to check the wheel bores. What he is looking for is, if I understood this correctly, a .005" clearance between the axle and wheel bore. Once he know the wheel bore size he then polishes the axles down to achieve the .005" clearance.

i.e. .092" axle. Wheel bore gauged out to .096" leaving a clearance of .004", this is too tight for what he runs. So now he polishes the axle down to .091" to give a .005" clearance.

Opa correct me if I'm wrong here, is this correct in what you were trying to say?

DD4H has a predrilled block that is quite good. However, IMO a serious racer should use the bent wheel on the DFW. You have much more flexibility to fine tune your car during testing both on a track as well as on the Test Board. E.g., what I do is set my car steer initially at 12 inches over 8 feet. Run a couple of tests on a track, then increase/decrease the DFW until you get the best time. I totally ignore the COM.

re. rear wheels. 3 degree cant is good. But no toe-in or toe-out on the rears. Use the Silver Bullet and make them absolutely parallel. For me, I don't want any more than 1/5000 difference between the axle and wheel bore (I hate sloppy wheels). Use a caliper (on the axle) and several pin gauges from 3000 up to 7000 (on the wheel bore). Usually that means I start with .092 axles and during the polling process,carefully take meat of the axle until it reaches 5000th with the wheel bore.

"take meat of the axle until it reaches 5000th with the wheel bore."

Thank you, I'm not sure what that means though?

 

[1reason]

Let me try to straighten this out for you 1reason.

I think what Opa was saying is, when using a .092" axle, he would use some pins gauges from .093"- .097" to check the wheel bores. What he is looking for is, if I understood this correctly, a .005" clearance between the axle and wheel bore. Once he know the wheel bore size he then polishes the axles down to achieve the .005" clearance.

i.e. .092" axle. Wheel bore gauged out to .096" leaving a clearance of .004", this is too tight for what he runs. So now he polishes the axle down to .091" to give a .005" clearance.

Opa correct me if I'm wrong here, is this correct in what you were trying to say?

DD4H has a predrilled block that is quite good. However, IMO a serious racer should use the bent wheel on the DFW. You have much more flexibility to fine tune your car during testing both on a track as well as on the Test Board. E.g., what I do is set my car steer initially at 12 inches over 8 feet. Run a couple of tests on a track, then increase/decrease the DFW until you get the best time. I totally ignore the COM.

re. rear wheels. 3 degree cant is good. But no toe-in or toe-out on the rears. Use the Silver Bullet and make them absolutely parallel. For me, I don't want any more than 1/5000 difference between the axle and wheel bore (I hate sloppy wheels). Use a caliper (on the axle) and several pin gauges from 3000 up to 7000 (on the wheel bore). Usually that means I start with .092 axles and during the polling process,carefully take meat of the axle until it reaches 5000th with the wheel bore.

"take meat of the axle until it reaches 5000th with the wheel bore."

Thank you, I'm not sure what that means though?

Oh wow, ok, I think I have that. I understand, but not sure my skill level will get me there (going to try though and it's a great thing to talk about to my son)

Once again demonstrates the best part about pinewood derby is what you learn, even if my son thinks it's the trophies (for now)

 

[IAE Racing]

Don't worry, a lot of the rest of us have not gained that skill either. If you are using out of box axles, just try to remove as little as possible, while achieving the finish you desire.

 

[The Iceman]

I think what he needs to know is, if you stick with a straight DFW Axle hole and a bent axle, then you can turn it to adjust your toe. Then you can change how many inches your car steers for every 4'. Every car is different so you would never want it not to be adjustable!

As for the rears, you need a Negative Camber, a perfect 3 degrees. So when the car rolls the tires always navigate to the end of the nail away from the body. To do this perfectly I snagged the Silver Bullet.

 

[plhiatt]

When I started I did do that, I found out a way to do it accurately as well.
I spent a long time trying to get it to work right.
But after i finished the cars some came out and needed a touch more steer
and some came out needing a little less. I know what your thinking but
bending a front axle is the way to go. Its so much easier.
If you do drill the fdw figure in a touch too much steer in the angles.

 

[1reason]

Don't worry, a lot of the rest of us have not gained that skill either. If you are using out of box axles, just try to remove as little as possible, while achieving the finish you desire.

I really could have used your advice about three years ago.... lol I took so much material off, axles out of the box were better.

I really feel bad for my oldest son watching his younger brother winning while he "almost made it" three years in a row.

Tough being the "guinea/practice kid". As the oldest I know how he fills.

 

[IAE Racing]

I really could have used your advice about three years ago.... lol I took so much material off, axles out of the box were better.

Been there, my friend.

 

[Guest]

I think what he needs to know is, if you stick with a straight DFW Axle hole and a bent axle, then you can turn it to adjust your toe. Then you can change how many inches your car steers for every 4'. Every car is different so you would never want it not to be adjustable!

As for the rears, you need a Negative Camber, a perfect 3 degrees. So when the car rolls the tires always navigate to the end of the nail away from the body. To do this perfectly I snagged the Silver Bullet.

Well said Iceman,

1 other thing.

The way to keep as much of the material on the scout axles as possible, ( thereby eliminating slop) is to hold them in your fingers and only file /sand away at the crimp marks.

 

[OLD BLUE RACER]

Is there a picture of a axle for the dfw what it should look like as far as the bend this is my daughter's last pinewood derby and I want it to be at least a top 3 finish going for the piano look this year with last song or cord on it

 

[cycrunner]

Wow, 0.005" diametrical clearance seems too much from my experience. For an axel diameter of .093", for example, I ream the bores of the wheels I make to .095". Doc Jobe has a mathematical analysis (and test results) showing that more speed is obtained by reducing the clearance between the bore and axel. He shows, and testing demonstrates, that for a fixed axel size, as a small bore diameter is increased for more clearance the car slows. Of course you need room for lubricant. The oil viscosity will impact just how close the diameters can be - but less clearance in general should be faster. I use Krytox 100 oil or some modification of it.

 

[Obsessedderbydad]

Is there a picture of a axle for the dfw what it should look like as far as the bend this is my daughter's last pinewood derby and I want it to be at least a top 3 finish going for the piano look this year with last song or cord on it

I'll try and post a picture tomorrow for you. I'll show you DD4H bought bent axle and the one I did. It's really quite easy. The best thing to do is what you're asking, get something to compare it to. That's why I bought one that was bent. As far as grooving one and bending it yourself, it's pretty simple.

 

[The Iceman]

[

Well said Iceman,

1 other thing.

The way to keep as much of the material on the scout axles as possible, ( thereby eliminating slop) is to hold them in your fingers and only file /sand away at the crimp marks.

Laserman, Dang that is excellant advice!!!

Thanks

 

[speedwriter]

Question: if using standard BSA wheels (bore = .0965) and BSA axles (Dia. = .087 or less after polishing) would you still cant the rear axles? and to what degree?

 

[ngyoung]

Yes . around 3*

 

[chromegsx]

I'm not a big fan of .005" either. I did that this year because of the poor quality wheels we got and didn't like it. Too much play for me... But I'm no pro...who knows. If I have the wheels to do it for my awana cars,.. I like the steady ness that .093 axles and .096 (started with .0955) wheel bores gave me, finger spin wasn't that great but man did my car out pace others that I had...maybe just a better built car. Don't know. Maybe scout wheels like more clearance.