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Recess counter sunk screw holes in carbon fiber chassis

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Recess counter sunk screw holes in carbon fiber chassis

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Old 08-08-2019, 02:48 PM
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Default Recess counter sunk screw holes in carbon fiber chassis

i picked up a couple of Associated 12R 5.2 knockoff main chassis and rear pod carbon fiber pieces a few years ago from someone on here. I just pulled them out and found out that the recessed countersunk holes aren’t deep enough. The result are the screws aren’t flush with the surface of the chassis when fully seated. Shat are my options? Is there a bit I can purchase to deepen the recess (1/16”!or less) I know I have to have a mask on and keep the dust to a minimum.
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Old 08-08-2019, 03:12 PM
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You will need to know the head angle of the intended hardware. And, use a drill press.

https://www.mcmaster.com/countersinks

Last edited by AngryRog; 08-08-2019 at 03:13 PM. Reason: Add
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Old 08-08-2019, 03:18 PM
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Atlas tools, double ended 2 flute 90° 1/4 countersink carbide bit. About 20 dollars
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Old 08-08-2019, 07:19 PM
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Perfect, thanks AngryRog and Racermac73, great info. Just what I was looking for.
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Old 08-10-2019, 09:13 AM
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Or you could grind down the head of the screws. This works as long as you have a deep enough hex hole.
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Old 08-10-2019, 10:35 AM
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Use a drill press with a depth limit on the head travel down. also use a vacuum with hepa filter next to press bead in the direction of rotation or chips travel.the more flutes the better counter sunk hole .less chance of tears.https://drillsandcutters.com/1-4-90-...afcde55def9557
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Old 08-10-2019, 06:44 PM
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Originally Posted by glennhl View Post
Or you could grind down the head of the screws. This works as long as you have a deep enough hex hole.
doing this will remove any hardening, and make the screw weaker not to mention losing the depth in which the Hex Driver can engage is not a good thing.

Just get a correct countersink, Dragonplate may be able to advise you as to which bit. I use Ti/Ni coated CS bits.
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Old 08-10-2019, 07:34 PM
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Different screws might be easier, titanium tends to have a thinner head than steel. Steel screws vary from company to company also so a different steel might be ok
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Old 08-10-2019, 11:30 PM
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Originally Posted by 1/8 IC Fan View Post
doing this will remove any hardening, and make the screw weaker not to mention losing the depth in which the Hex Driver can engage is not a good thing.

Just get a correct countersink, Dragonplate may be able to advise you as to which bit. I use Ti/Ni coated CS bits.
Use steel screws, not titanium, and just go slow on the grind so you don't overheat the head. Drill and tap a 3mm hole/thread into a piece of aluminum. You can then hold onto the aluminum while you grind and the aluminum will help carry away the heat you generate by grinding the head. And as I stated before, make sure you have a deep enough hex hole. I would grind some steel screws down before buying countersink tooling to deepen the countersink holes and risk breathing in some really nasty stuff.
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Old 08-12-2019, 04:20 AM
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Drill presses, grinding heads on screws.... SMDH
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Old 08-13-2019, 03:50 PM
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Originally Posted by Slo_E4 View Post
Drill presses, grinding heads on screws.... SMDH
Machining holes in carbon graphite, a carcinogen ...SMDH
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Old 08-13-2019, 04:01 PM
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Originally Posted by glennhl View Post
Machining holes in carbon graphite, a carcinogen ...SMDH
Known to the state of Cancer to cause California.
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Old 08-13-2019, 04:13 PM
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Actually thinking about it, I wouldn't machine on the graphite and I wouldn't grind down screw heads. I just throw away the plates and buy new ones. But that's because I'm lazy and extra cautious.
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