Alingnment trouble

Dec 16, 2015
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Getting started on derby cars for this year, I have the Silver Bullet Pro, I am having problems with wheels not moving away from the body on slow roll tests. Upon inspection I can see and feel slop in both rear bushings in the jig when I insert the drill bit by hand. The bit came with the jig. When I try the front bushing that I have never used (the lifted wheel) the fit is snug. I have only used this twice, could the bushings be worn out already?
 
Mine is the same way. The bushings that I use have more play than the new ones that I don't. I don't consider them to be worn out. More like being broke in.

As for the alignment not being perfect, folks can say what they want, but in my humble armature opinion, any bushing that supports the drill bit at only one point will have some wiggle room. I consider it to be like any other tool or instrument in that it is how the craftsman learns to use it, that makes the difference.

DD4H put out a video showing that a slight pressure on the drill motor towards the front of the car could help gain more consistency, but I wasn't able to get that 'race ready' drill that I was looking for.

Personally, I will never drill enough blocks to become an expert, without some additional help. So for the last few weeks, i have been working on a jig to put the Silver Bullet Extreme in that I call my 'jig jig'. It will support the drill bit along the length of the shaft with (what i expect to be) perfect alignment to the single point of contact in the bushing. If I am successful I will be able to drill race ready blocks consistently. If I am not successful I will drill them as close as I can and perhaps become more proficient in altering the holes that need adjustment after drilling.

Just my 2c.
 
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You neee to order a few drill bits not all are the same size and find one that is snug...i dont know how serious you are, but the roll test is not that good.. if you want top speed you need to do 123 block method
 
I ordered some pin gauges and 123 blocks yesterday and will get a few #43 bits as well thanks guys.
 
Get #43 Aircraft drill bits. They are 6" long and help check your alignment without opening your hole. I have been using the same two for more than 5 years (Don't drill with them... just check alignment with them). Works perfect.
 
I solved the loose drill problem by buying the next size bigger bit and sanding it down in a drill press until it just slid in the bushings.
 
I’d recommend a test drill in some wood and see how your axles fit that hole. Cross those T’s and dot those I’s now so there’s no surprises.
 
Is it both sides not moving out? If so could be a front end height issue. Are you testing this with the front wheel on it or are u supporting the front end with something else while doing this test? Just some other things to consider...

Scott
 
Drilled several holes and when I check for toe most of them have toe in on one side and the slow roll test confirms the wheel with toe doesn’t migrate out going backwards and will turn the car towards the side that does. Going forward the wheels migrate out just the side with toe goes slower. In this scenario how would you fix the toe?
 
One other issue with roll tests can be with your wheels and axles. You need to roll test with a bent axle because the front hole is a bit higher than the rears.

Are you drilling on high speed? If you are getting consistent toe drills drill applying slight pressure while you are drilling to correct it.

Try a different drill bit for sure also.

You can also send it back and I can check it and if it is bad I will send you a new one.
 
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