Right/Left cube placement

[B_Regal Racing]

I think I would build a new car for a few reasons and chalk this up to a learning experience, especially if this is a "dad car" - it might be a harder sell if it was your son's car. BUT- The axles are glued in and you could have an alignment problem. They are scout axles and I suspect you polished the crimp marks off. Scout axles are already small in diameter and by polishing off the crimp marks, they are now even smaller. Bent axles, no matter how small, and small diameter axles easily lead to wiggling, especially with aggressive weighting. Scout axles are not straight to start with and they probably needed to be tuned in the rear.

Build a new car and re-use the wheels. Polish new axles but do not remove the crimp marks; just polish them. And polish lightly - do not remove too much material and make the axles smaller in diameter than they already are. Cut a groove in the axles heads for tuning the rear. Put clear Teflon or PTFE film down both sides of the car (get from McMaster Carr), especially if you are covering the top with vinyl / monokote. You probably cannot use washers as per the rules, but I doubt there is anything that says you can not use film. It's better (and easier) than nail polish. If you are not running fenders, you can do all of this in a few hours.

maybe buy these as an axle alternative:
https://www.derbydad4hire.com/BSA-Elite-Axles-A-BSAE.htm

My 2 cents...

 

[ScoutDadinVA]

I think I would build a new car for a few reasons and chalk this up to a learning experience, especially if this is a "dad car" - it might be a harder sell if it was your son's car. BUT- The axles are glued in and you could have an alignment problem. They are scout axles and I suspect you polished the crimp marks off. Scout axles are already small in diameter and by polishing off the crimp marks, they are now even smaller. Bent axles, no matter how small, and small diameter axles easily lead to wiggling, especially with aggressive weighting. Scout axles are not straight to start with and they probably needed to be tuned in the rear.

Build a new car and re-use the wheels. Polish new axles but do not remove the crimp marks; just polish them. And polish lightly - do not remove too much material and make the axles smaller in diameter than they already are. Cut a groove in the axles heads for tuning the rear. Put clear Teflon or PTFE film down both sides of the car (get from McMaster Carr), especially if you are covering the top with vinyl / monokote. You probably cannot use washers as per the rules, but I doubt there is anything that says you can not use film. It's better (and easier) than nail polish. If you are not running fenders, you can do all of this in a few hours.

maybe buy these as an axle alternative:
https://www.derbydad4hire.com/BSA-Elite-Axles-A-BSAE.htm

My 2 cents...

Yes learning experience indeed. After letting my kids do their own axles I did mine and didn't realize the whole not to file off the crimp marks approach. I usually use the axle press to straighten then cone the underside of the nail head, which also takes care of the head flashing on opposing sides of the head. I did notice the diameter of the heads varied a bit depending where I used my calipers, so I get that these are not straight. I just didn't realize the extent it would impact performance until now, i.e. the tuning with 16 rotations and such. My 4 YO girl seems all-in on being a scout (she did 70% of her axle polishing!) so I may have a few more years to use this lesson in future builds.

What a fun hobby, I like that I am learning something new every day throughout the builds and can teach the kids then go experiment. I just need a timer for my track. If you have any DIY instructions for one please forward, or know of any that secondhand available.

At this point, I don't have the hours avail to build a new car before the race on Saturday. Plus I would be competing maybe against one other person running his car from 2016, so it is more of a personal best endeavor. This car I tested was running ok, a little shaky but quick. My boy convinced me not to use the pledge-graphite burnish and just add graphite, but still running fast seemingly.
Thanks, comments always welcome!

 

[ScoutDadinVA]

Won the Pack!! There was major drama. Ill update with details soon. Hint the repair we made during testing resurfaced...killed time but didnt matter. Thanks for all of the advice, it definitely helped!!

 

[Loud2ns]

Won the Pack!! There was major drama. Ill update with details soon. Hint the repair we made during testing resurfaced...killed time but didnt matter. Thanks for all of the advice, it definitely helped!!

What a tease!!

 

[ScoutDadinVA]

Won the Pack!! There was major drama. Ill update with details soon. Hint the repair we made during testing resurfaced...killed time but didn't matter. Thanks for all of the advice, it definitely helped!!

Ok so this was a close one this year.. My boy won his Web1 class handily by 3 hundredths of a second. So we were excited we would advance to Districts, however the drama started at heat 2 of the pack finals. Up to the first round of finals we had been running 2.37 to 2.39(29 ft wooden track), then a dreaded 2.49 appeared. I was like uh oh Houston we have a problem. I didn't know if it was a track /race management issue or the car. I was helping as the starter and i mentioned there could be an issue..I was overruled. I couldn't tell if the other cars in that heat were running slower than their other runs so I didn't have a case. I was thinking my sons car was toast at this point.
It gets worse. . Next heat after the cars slam into the padding I hear we have a wreck. The car ran fine despite this and it pulled the average back up some.. but yep the worst just happened, the wheel that was adjacent to the crack that occurred in testing I presumed gave way and we lost the back left wheel. Only the aluminum tape was holding on the chip and the wheel flew a couple feet away. At this point reality set in and I knew my scout was going to be crushed, and was thinking this could be a good life lesson. I didn't give up and said let me try to glue this thing back on.. however no one had any glue! So I remembered I had brought some for checking in the night before and had it in my car so my son and I raced outside to get it. Once inside I carefully glued the chip in place the inserted the axle..I held it for a good 3 mins with significant pressure. Before i had placed it on the track i saw a cube was missing and frantically searched for it, finding it in the retrieval container..then reattached it close to the original spot and inch behind the dfw. They bumped our final heat to the last run and believe it or not, it ran faster, setting the track record for the day. I couldn't believe it!! Despite this I had no hopes for a 1st place give the 2.49 of the second heat. As we watched the results and saw that we won by 4 thousandths of a second, I thanked my lucky stars for this community as I know if I hadn't made some of the adjustment this would have been very different for my scout's car. This is our second pack championship in 3yrs and we hope to do well at Districts in March. The All Comers race went perfectly..my 4YO girl placed first and I second with 2.3733 and 2.3979 with the third place winner well back at 2.4557. Thanks again for everyone's help on this, greatly appreciated!!

 

[Loud2ns]

Congrats, glad it held on for the win!

 

[Jupiter 2.9]

It’s always special when the crew chief wins one in the pits.

 

[ScoutDadinVA]

It’s always special when the crew chief wins one in the pits.

So true Jupiter 2.9..a story that will be retold for decades!

 

[CDubya]

B_Regal Racing posted this checklist years ago in response to a question about wiggles. I think it’s the most complete answer to your question that I’ve come across. I keep this list handy as I tune our scout cars.


Consider:

1) clean wheels of debris, graphite, and wax with mild abrasive pad/micromesh

2) check rear alignment

3) check steer; add more

4) rear wheel gaps too large; tighten gaps; check front as well

5) move weight forward (only adding a few grams to the FDW)

6) check rear wheels; hubs or edges deformed; replace

7) bore diameter not equal when measured at inside and outside hub; replace

8) repolish a new set of rear axles (diameter is too small)

9) repolish a new set of rear axles (rear axles slightly bent)


Could be any one or all of these things. 1 thru 5 are easy to do and usually can correct most problems.

Brand new to all of this but wanting to learn. How to you check the rear alignment and what exactly does that mean. (number 2 on the list) and what is number 7? The bore diameter? Figure the more I know before I start building the better.

 

[T-Bone Racing]

Checking rear alignment is making sure your axles are perfectly straight, having no toe in or toe out. After you drill your axle holes, there could be toe in or toe out if there was an issue with the drill. The way to check this is by putting pins in the rear holes and placing them against 1-2-3 machinist blocks. Put one pin to the block with your finger and tap the other side. If it bounces against the block like crazy, then you have toe in. If the pin is weirdly bent out, then you have toe out (toe in is more common).

Number 7 is bore diameter but that is not of high importance when you first start out. It’s something to consider when polishing so that you don’t over-polish, similar idea with axles. Bore diameter is also measured with pins.