ladder car issues

[dan s]

Hi All, we tried our hand at making a ladder car. I was able to get the car to .8 ounces which was frame, wheels and axels. We went and ran the car against my canopy car with the same COM, change the tires back and forth between the 2 cars and ran in all three lanes multiple times. The Canopy car consistently won by .05 to .1 of a second. what did I do wrong?
COM on both cars was 5/8, the canopy car had 3.6 ounces of tungsten the ladder car had 4.2 ounces. The Canopy car ran looser and bounced around a bit but was still faster. The ladder car had 12 tungsten cubes behind axels and 12 tungsten cubes just in front of axels. the canopy car is 1/8 thick in nose and 5/16 thick in back, ladder car is thinner in nose and same thickness in back. I was unable to measure weight displacement on rear tires but the ladder car also ran solid with minimal shifting from side to side. Any suggestions? thank you all so much for any help.
Dan

 

[Castoro Racing]

Hi All, we tried our hand at making a ladder car. I was able to get the car to .8 ounces which was frame, wheels and axels. We went and ran the car against my canopy car with the same COM, change the tires back and forth between the 2 cars and ran in all three lanes multiple times. The Canopy car consistently won by .05 to .1 of a second. what did I do wrong?
COM on both cars was 5/8, the canopy car had 3.6 ounces of tungsten the ladder car had 4.2 ounces. The Canopy car ran looser and bounced around a bit but was still faster. The ladder car had 12 tungsten cubes behind axels and 12 tungsten cubes just in front of axels. the canopy car is 1/8 thick in nose and 5/16 thick in back, ladder car is thinner in nose and same thickness in back. I was unable to measure weight displacement on rear tires but the ladder car also ran solid with minimal shifting from side to side. Any suggestions? thank you all so much for any help.
Dan

Did you cover the top and bottom with tape or another covering for testing? Pictures would help. There are ton of variables that may have nothing to with the way the body was constructed including how good the rear drill is the steer on the cars how the car tracks/rear wheels centered.

 

[ironband]

Dollars to Donuts the alignment is worse on your ladder car. What did you use to drill it?

 

[DerbyDad4Hire]

Has to be alignment or check to see if a rear wheel might be too close to the rail on a slow roll. I assume you made a rail runner.

 

[dan s]

Did you cover the top and bottom with tape or another covering for testing? Pictures would help. There are ton of variables that may have nothing to with the way the body was constructed including how good the rear drill is the steer on the cars how the car tracks/rear wheels centered.

I did not tape the bottom closed. I used rail riding, dominate wheel on rail, 3 to 4 inches over 4ft. I thought you used the dominate front wheel to steer. I did not tune the steering using back wheels, on either car. Weights were taped in place on ladder car so I could adjust placement.

 

[dan s]

Dollars to Donuts the alignment is worse on your ladder car. What did you use to drill it?

i did adjust hole place, found both cars fasted was 1.5 degrees front and 3.5 rear. I used an adjustable Wilton vice and drill press to drill axel pilot holes.

 

[dan s]

Has to be alignment or check to see if a rear wheel might be too close to the rail on a slow roll. I assume you made a rail runner.

first off thanks derby dad, I have been trying to learn as much as I can from your posts(as well other posts in this forum). I did not indent front dominate wheel 1/16. I will make that adjustment to ensure back wheels keep off center rail.

 

[dan s]

I did not tape the bottom closed. I used rail riding, dominate wheel on rail, 3 to 4 inches over 4ft. I thought you used the dominate front wheel to steer. I did not tune the steering using back wheels, on either car. Weights were taped in place on ladder car so I could adjust placement.

I did use the blue derby pro wheel gap tool on both cars.

 

[dan s]

Did you cover the top and bottom with tape or another covering for testing? Pictures would help. There are ton of variables that may have nothing to with the way the body was constructed including how good the rear drill is the steer on the cars how the car tracks/rear wheels centered.

 

[dan s]

 

[dan s]

sorry wheels are dirtier then when raced, also i routed ladder leaving a thin layer of wood instead of taping both sides

 

[dan s]

 

[Castoro Racing]

Could be the angle of the picture but the rears seem to have very different angles, I think it's safe to say the rear alignment is the main problem. I have had more luck filling in the slots and then drilling with a drill jig. You can always drill holes to show the axle points if needed for inspection.

 

[Castoro Racing]

Also not sure what the blue pro derby gap tool is but I would bet it's much larger than you want.

 

[dan s]

Also not sure what the blue pro derby gap tool is but I would bet it's much larger than you want.

it is about same width as a credit card (picture below). would you recommend something else?

 

[dan s]

Castoro, we are competing in race at end of month. what is your feeling about cutting in dominate front wheel 1/16 of an inch?

 

[DerbyDad4Hire]

Dan your alignment is BAD. The rear end is a mess looking at the pics. I am sure one of your rear wheels is on the rail too or at least hitting it.

 

[DerbyDad4Hire]

The wheel spacer is too big too.

 

[Jimmy & his 2 Kids]

it is about same width as a credit card (picture below). would you recommend something else?

I’m no pro, but my cars do well at the Awana level and not too bad in league all things considered and only because I do as I am told and have had lots of help.
I only eyeball my gaps but I do know I barely go half a credit card width. I know guys typically have thickness gauges for measuring if nec. On a properly drilled, well aligned car the gaps are very small to ensure best results.
Hope that helps but listen to John and the others.
Jimmy
Ps... definitely do 1/16” offset DFW for rail riding. Your asking for trouble if you don’t.

 

[dan s]

I’m no pro, but my cars do well at the Awana level and not too bad in league all things considered and only because I do as I am told and have had lots of help.
I only eyeball my gaps but I do know I barely go half a credit card width. I know guys typically have thickness gauges for measuring if nec. On a properly drilled, well aligned car the gaps are very small to ensure best results.
Hope that helps but listen to John and the others.
Jimmy
Ps... definitely do 1/16” offset DFW for rail riding. Your asking for trouble if you don’t.

Thanks, Jimmy. I appreciate the help, I believe in a earlier post someone said to use an index card with three kids in the house I have plenty of those. I am going to listen to all of the suggestions and rebuild the ladder car. I also want to re-drill the axel holes in the other 2 cars. I am thinking of making paste from sawdust and wood glue to fill in the axel slots and then re-drill . thoughts?