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Is it possible to over polish a wheel bore?

Discussion in 'Ask The Pros' started by tomb, Apr 10, 2019.

  1. tomb

    tomb Pack Champion

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    I'm using the DD4H black ice system for the first time and am wondering if there is such a thing as polishing them too much and too aggressively with a tamiya swab and pipe cleaner (with protected tip of course)? I know that John says till they're race ready but I'm not really sure yet what that looks like. Is there a guideline as to how long to polish each wheel and is there a point where you can over do it and compromise the bore size?
     
  2. Mojo Racing

    Mojo Racing National Contender Pro Racer

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    I tell boys I coach to turn the drill slow (As in VERY slow), and count to five pushing the wheel in on the Q-Tip stalk and count to five pulling the wheel out on the Q-Tip stalk... and do that five times.

    It works well for them.

    But to answer your question... yes. You can over polish the bore. If you turn the drill too fast or run it too long, it will open the bores up, and the wheels will feel sloppy on the axle.
     
  3. Jimmy & his 2 Kids

    Jimmy & his 2 Kids League Racer

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    And going too fast you can literally melt them. I’ve melted bores going to fast with both Tamiyas and Qtip stalks.
    Also if I may strongly recommend ... get an eye loupe. Like a jewelers loupe. I got one at Menards for like $6. Opened up a whole new world for me being able to totally see up close just what’s going on in there and also being able to see defects and then results from proper polishing.
    I took last years Awana GP wheels off our cars to check them out and was horrified. Lol
    Hope that helps some!
    Jimmy
     
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  4. tomb

    tomb Pack Champion

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    Thanks so much; very helpful and a little scary.
     
  5. tomb

    tomb Pack Champion

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    So I had already polished a few; I don't really think I overdid it but what would be a good check? Do you just go by feel and see if you have too much slop on the axle?
     
  6. Ballistic Racing

    Ballistic Racing District Champion #1 Ranked in the USA Pro Racer Pro Race Winner

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    Get yourself a good set of pin guages. I have a set from .095-.099
     
  7. Jimmy & his 2 Kids

    Jimmy & his 2 Kids League Racer

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    Hey Ballistic, where’d you get your set?
     
  8. Mojo Racing

    Mojo Racing National Contender Pro Racer

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    I got a whole set from Amazon
     
  9. HurriCrane Racing

    HurriCrane Racing PWD Royalty Pro Racer 25+ Pro Race Wins! National Champion

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    A jewelers loop works well for inspecting bores.
     
  10. Ballistic Racing

    Ballistic Racing District Champion #1 Ranked in the USA Pro Racer Pro Race Winner

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    I got mine from McMaster-Carr
     
  11. tomb

    tomb Pack Champion

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    Thanks HurriCrane; I've got a jewelers loupe coming in the mail. I saw an old video by Cramjet and it sold me. DD4H was out of stock but I found the same one on Amazon.
     
  12. bracketracer

    bracketracer PWD Royalty Pro Racer

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    When you get your pin gage set, be sure to blunt at least one end on each pin and polish just that little rounded over tip highly. Don't polish very far down the length, you don't want to change the size, but as delivered they can be extremely sharp!
     
  13. Reecedad

    Reecedad Council Champion

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    If your bores measure over 98 then you've polished too much
     
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  14. tomb

    tomb Pack Champion

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    So what should a really good typical bore measure? I really apologize for my ignorance and appreciate the patience.
     
  15. Reecedad

    Reecedad Council Champion

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    If your axle measures .0925-.093 a good bore size will be .0975-.098
     
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  16. tomb

    tomb Pack Champion

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    Thanks; this is very helpful...I am using the 93TX axles from DD4H.
     
  17. e/o

    e/o Pinewood Ninja

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    If you're very worried about over polishing I would watch DD4H's bore polishing video because he's not nearly as delicate with polishing as some posts on here imply, and he clearly knows what he's doing. I think it will make you less concerned.
     
  18. Mojo Racing

    Mojo Racing National Contender Pro Racer

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    Yeah... but you gotta remember... he is doing that for a video, and he has been doing that for YEARS.

    If a new person comes in and tries to replicate what he does, that person will almost always open the bores or burn the hubs.

    Cub scout wheels are not indestructible and if you go too fast or are too aggressive with your polishing, you will tear that wheel up. Have no doubts.
     
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  19. e/o

    e/o Pinewood Ninja

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    Fair point, I’m just saying wheel prep got less miserable for me when I realized I didn’t need to treat wheels like newborn children.

    Now if I could figure out how to take less material off scout axles that would help a whole ton.
     
  20. Mojo Racing

    Mojo Racing National Contender Pro Racer

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    don't use sandpaper that is courser than 1,000 grit, and make sure the paper stays wet
     

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