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Post by pinedust on Mar 21, 2011 11:05:30 GMT -7
I have made at least 6 cars using the block and never had a problem until now. I'm off somewhere in my setup, but everything I have checked looks OK. drill table is square to chuck. 3 wheel r-r, pure stock setup with canted rears. car rolls forward rear wheels stay in. back wards rear wheels come out. seen something in a thread before but can't find it. any input would be great. Thank you in advance
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Post by W Racing on Mar 21, 2011 19:56:42 GMT -7
Pos or Neg cant on the DFW?
Wheels coming in while rolloing forward would be toe in.
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Post by *5 J's* on Mar 22, 2011 4:57:02 GMT -7
sounds like a bit of toe-in. I would put a couple inch drill blank into the axle hole and using a quality square verify that the axle holes are perpendicular to the body. Or - throw that body into the kindling pile and drill another one.
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Post by Wood Butcher Racing on Mar 22, 2011 7:30:05 GMT -7
I think if you were to lower the front it will fix the drift in the rear wheels. The whole purpose of drilling holes for the (rear) axles is to align them perfectly. That is to say, at a perfect right angle to the car's body and in line with each other. When this alignment is correct the wheels will not fight each other. Now when you add canting (to move the rear wheels away from the body) you have also added another axis to manage. This axis is front to back or vertical. Your (rear) axles should have a 90 degree angle to the body (horizontal) and also up and down (vertical to the track surface). If you were to raise or lower the front of the car it will affect this 2nd axis. I have read in a thread that this is one of the things to consider when drilling your holes. The height of a wheel is different when the axle is angled than when flat. Think about it. Just my
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dko
STOCK
God Bless America! [Mo0:19]
Posts: 48
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Post by dko on Mar 22, 2011 14:02:47 GMT -7
Thanks Wood Butcher Racing your post was very informative. Definitely food for thought. Pinedust, I would probably just start with a new block for racing but it would be cool if you could experiment with this one and see if Wood Butcher's suggestion fixes it.
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Post by *5 J's* on Mar 22, 2011 19:23:39 GMT -7
I think if you were to lower the front it will fix the drift in the rear wheels. Good point Wood Butcher, but wouldn't you need to raise the front end to correct toe-in if you have negative camber in the rears?
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Post by Wood Butcher Racing on Mar 23, 2011 7:43:43 GMT -7
My dyslexia may be showing I think you may be right. And there may be more than one way to correct the problem, but that axis is where the problem lies. (or so I think)
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Post by *5 J's* on Mar 23, 2011 7:48:56 GMT -7
It's an excellent suggestion depending on how far along in the build.
Hopefully everybody is following John's recommendation and checking this right after drilling. Easier to discard a block at this point before investing too much labor.
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Post by pinedust on Mar 23, 2011 9:02:07 GMT -7
Thanks a million everybody. I found my problem. I have a low end drill press and I had increased the speed to about 3000 rpm, my thinking was such a small hole and wanting it to be nice and straight that speed would be best. I'm using carbide bit from ___. I got some scrap wood and went back at it. well that little bench top drill press can't handle that kind of rpm without vibrating so bad that it caused the block to walk just enough to screw things up. I slowed the rpm down to about 1000 rpm and things turned out better not great but better. The drill press had been used a lot since the last car was drilled. it served its purpose and its time to move on to something better maybe proxxon $$. meanwhile I will be buying ___ blocks for now. dko & butcher your 2 cents gave me a reason to play with the front end height I'm curious to see if it can be fixed. 5kids Wheels are purestockers, axles are 93's. wr pos dfw. 5j's you are spot on, toe in (more on one side than the other). thanks for the fast response time everybody, maybe with all your help I can keep from entering the same car in the purestock and turtle race in the same night Thanks again for the help!
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Post by Wood Butcher Racing on Mar 23, 2011 10:06:23 GMT -7
Well I can't take credit for it. I did find the thread if anyone is interested. I just don't know how to clip in the link. Go to the Jewkes product section and open the BLOCK sub board. Read the thread "The Block". It's all in there.
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Post by Exorcist3D on Mar 23, 2011 14:40:50 GMT -7
I had the same walking problem a couple weeks ago. I've got about 8 hours in figuring out what was happening. In my case it was only the rear wheels that would end up crooked. I found that with the canting pin in place the friction to the table was reduced and the vibration of the drill would cause the block to walk around, even though I was holding it in place. (as compared to no pin when drilling the fronts). I would suggest that you do really do want to use the highest rpm available on your drill, so I suggest making an end stop (clamp) and then your problems will go away. (I assume you already have a fence mounted to the table as the video shows) The fence + end stop controls 2 directions and then using your free hand you can push the block "into the corner" and drill with the best precision your drill is capable of.
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Post by pinedust on Mar 25, 2011 8:26:02 GMT -7
Thanks 3d I will try that next on a piece of scrap and see what happens maybe I will be able to hold off on another drill press for awhile. I orded a drilled block from John at ___, It's here already. Lucky for me his service is as fast as his cars. Thank you for the help.
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