Am I being too critical?

[Batman]

Working on a car for districts. Bought sugar pine block, bought a block for Jewkes, SB wasnt availible. Set up a fence, drilled the block, first try I was off a couple thousanths, 2.5 or 3, from the rear. Okay, no sweat, just flip it over and use top half. Drilled the cants, and agian off 1.5 to 2 thousanths. Cussing like a sailor, now! Cheat them in alittle and I am close but when I test one wheel migrates alittle faster. To me this means I wasnt perfect square??? Flip over and try again. Very close but again, one wheel migrates faster! Now there are enough holes that I feel like I need to start with a differnt block of wood. Back to regular blocks!

Should I go on with regular pine blocks or try to epoxy these screwed up holes?

Level of racing is district, but some rather stiff competition. Beating the head against the wall!

 

[zigzag]

My 2 cents - go with a regular pine block - just make sure it is good and square , etc.

 

[5KidsRacing]

I have only used Sugar Pine a couple times, all the rest were BSA blocks or pine/aspen blanks I cut from 1by's.... I would use a BSA block, just be a little selective and use one that is light and has a light grain.

 

[Kinser Racing]

Use some bsa blocks to practice on before using the best one.

 

[Batman]

How critical is it that both rear wheels migrate at the same rate? Is it possible that my homade groved axles are biasing my tests? They both migrate on each of the 6 blocks I have drilled. Always the left first and the right one 3-6 inches later. On a couple of the blocks it is 2-3 inches apart. but always the left first! Swapped axles, triple checked for a level plane on test board. Any other thoughts?

 

[Kinser Racing]

Is your table level?

 

[Batman]

According to my 4 ft level it is dead nutz! But I will turn the board around and see if there is a difference.

 

[Choo Choo]

Use a pool cue ball to verify your tuning board.

Choo-Choo

 

[BulldogRacing]

take the dfw out of the equation, or switch sides with the dfw and see if the same thing happens

 

[Batman]

Omg! I feel like a dipstick! Changed dfw and everything went opposite! It's all about wieght distribution! I feel like a dummy! 2 front wheels and all was in unison. Added a touch of weight to dominant side and all went in unison! Ugh!

 

[txchemist]

Don't be so hard on yourself- you just did an experiment and learned more than 99% of all racers.

 

[Batman]

I am wishing I had all of the blocks that I thru away now! I thought I was off on some minute amount!

 

[LightninBoy]

Is your table level?

 

[bracketracer]

Is it possible that my homade groved axles are biasing my tests? They both migrate on each of the 6 blocks I have drilled. Always the left first and the right one 3-6 inches later. On a couple of the blocks it is 2-3 inches apart. but always the left first! Swapped axles, triple checked for a level plane on test board. Any other thoughts?

I see you found your problem, I would also suggest that you use un-grooved axles, or even better- gage pins, to check the wheel migration so you don't risk scuffing the wheel bores.

You can take the DFW out of the equation by using the LightninBoy speed square method in the future. I don't even have to put weight in the car using the square. I did make sure to use a short enough screw to keep the body level for the test. I believe Bulldog made a video of how to do the test if you haven't seen it already.

 

[Batman]

Table was perfect level. According to a 4ft pro grade level.

FDW was right side. Left wheel would always migrate first, then 6" later the DRW. Always! On all the blocks!

Switched FDW to left side and NDRW would migrate first, and 6" later the other would follow. Always! Same action just in reverse

Put 2 wheels on the ground in front. Perfect migration. A ha!

Now I am learning something! A slight weight adjustments and perfect migrations! Go team!

 

[Batman]

Hate it that I pounded my my head for something I actually had right, but I feel like I learned something!

Gonna have to go buy a speed square! Lol

 

[GravityX]

Don't be so hard on yourself- you just did an experiment and learned more than 99% of all racers.

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[ngyoung]

You ever see Lightning boys method of using a speed square with a thumb tack taped to it? You set the nose of the car on the tack and slide the square along your board. Also are you weighing down the rear end with your roll test? If it is just wood and wheels you are not going to get accurate feedback. I usually just set a a couple oz of tungsten on top of the block at the back.