How to Precisely Check Alignment

Best place to find pin gages is McMaster Carr, although not the cheapest place. You may also want to search eBay, Zoro, Fastenal, etc...
 
Even in the half sizes too! Tough to beat that deal if you have a Prime account, free shipping! I seem to forget about looking at Amazon for some of these items.
 
Those pins on Amazon are class ZZ go pins, the ones on Mcmaster are class Z no-go pins. The ZZ's have a greater allowable tolerance so they will be cheaper. Probably absolutely fine for what we use them for, just be aware of the differences.
 
So, if you check alignment, and see a sliver of light, the remedy is to toss the block in the trash and start over, correct?
 
So, if you check alignment, and see a sliver of light, the remedy is to toss the block in the trash and start over, correct?

This alignment test is really really really .... really sensitive. Is exposes even the smallest errors. There is certainly a point where its close enough to perfect that getting more perfect would be of no benefit. I have no idea where that point is. So when going up against the best of the best - yeah I toss the block if I see light. Or I flip it over and try again on the other side.
 
I am using silver bullet pro and haven't gotten two axles to pass in about 12-15 tries. I have gotten one axle to pass a few times. I tried a car that was close, and the wheels were traveling in. The next car I tried that was pretty close worked great.
 
So, if you check alignment, and see a sliver of light, the remedy is to toss the block in the trash and start over, correct?
Fill the bad hole with toothpick and super glue then cut it off and sand it smooth and re-drill until u get it perfect. I do it all the time.
 
I am using silver bullet pro and haven't gotten two axles to pass in about 12-15 tries. I have gotten one axle to pass a few times. I tried a car that was close, and the wheels were traveling in. The next car I tried that was pretty close worked great.

Maybe check the alignment of your tool? Insert two .089" pin gages through the bushings, and check to see that they are meeting in the middle, and that they are parallel.
 
Maybe check the alignment of your tool? Insert two .089" pin gages through the bushings, and check to see that they are meeting in the middle, and that they are parallel.

I just checked, the tool is dead on. For some reason all the blocks I ordered have just a touch of play in the tool instead of over tight like ones I have had in the past. I am trying to press one side tight and clamp and I have had better luck doing that and drilling real slow. I have several bodies now that are perfect on one side and very very close on the other and they are passing the roll test, so I am thinking good enough for a scout race.
 
If you press it to one side, it will make a lazy drill with your car. One side will be a different angle than the other because one side is higher. Do both sides evenly
 
Damn, I wish I had thicker bodies. How do I get it square and even on both sides with a touch of play between the block of wood and the jig?
 
I have lots of blocks that were set aside as perfect for the snug fit. Then just before drilling, tested again and they were all too loose. Wait for a rainy day and they will be too tight. Moisture will come and go. Impossible to not have wood change somewhat. When I cut blocks, I cut inside the house @ 50% R.H. ( hooked up to a vacuum cleaner - I have not been caught by my wife yet) Then they should not need sanding, but often will need the tape to get snug. I have both thin and thicker shipping tape for shimming.
 
This alignment test is really really really .... really sensitive. Is exposes even the smallest errors. There is certainly a point where its close enough to perfect that getting more perfect would be of no benefit. I have no idea where that point is. So when going up against the best of the best - yeah I toss the block if I see light. Or I flip it over and try again on the other side.

So would you drill the wood block first and then start cutting it for weight pockets and so forth, or would you cut the pockets first and then drill? I normally do the last since I always thought that cutting a signification amount of wood away could change the alignment.