1. Please take 30 seconds to register your free account to remove most ads, post topics, make friends, earn reward points at our store, and more!  

Do router bit collets wear out?

Discussion in 'Luthier's Corner' started by tjclem, Mar 23, 2009.

  1. tjclem

    tjclem Supporting Member Commercial User

    Jun 6, 2004
    Central Florida
    Owner and builder Clementbass
    I am running into troubles with my Porter cable router. I have been using it in a bench dog router table to route my truss rod channels. I have had a problem with the bits rising up and making the channel too deep as I am cutting them.

    At first I thought I was not tightening them enough or trying to take out too much at a time but after scoring up the sides of the new Bosh bit where the router holds it and tightening it until the veins pop on the side of my head and only taking out a 1/3 of the depth of a $50 hard maple neck blank it did it again.
    When I raised the chuck above table height I could loosen it by hand. What the heck is going on. I know a lot of you are far more experienced than me I hope you have some clue. This is getting old and expensive!.. Thanks .....Tom
  2. Id also like to know - Ive recently had the same problem with scoring router bits, so as I got some new bits I also got a new collet in case. The new collet needs to be tightened much less, so seems to work, but could I have refurbished the old one?
  3. Collets do indeed wear out. What I've had happen is the ends of the inside diameter of the collet wears, making the bit run out, causing vibration & rough cutting. Everything wears out.

    Edit: Wouldn't know about refurbing, but a new one likely costs not much more than having a refurb done professionally, and doing it oneself is likely difficult if not impossible(semi-educated guess :rolleyes:).
  4. Probably - but get this - my Bosch router cost about £60 new, and it came with three collets, 6mm, 6.53mm and 8mm. And replacement collets are about £21 each. Thats why I was asking! :)
  5. Oh, I am NOT trying to discourage you doing it yourself, & I certainly understand the economics here; just guessing out loud that it would be hard to *fix* a worn-out collet. More accurately perhaps, I'm fairly certain I couldn't do it. :rolleyes:

    Edit: Just did the math; looks like you bought 3 collets & got a router for free. ;)
  6. tjclem

    tjclem Supporting Member Commercial User

    Jun 6, 2004
    Central Florida
    Owner and builder Clementbass
    Woodcrafters in Orlando has one so I am on my way this afternoon thanks .....Tom
  7. praisegig

    praisegig Supporting Member

    Jul 7, 2008
    Stephenville, TX
    When installing the bit into the collet, insert the bit until the shank reaches the bottom of the collet, then pull out it out about 1/8", before tightening the collet. Do not tighten the collet with the radius of the shank inside the collet, as when you tighten the collet the bit will try to raise up and work loose when cutting. This problem is more common on 1/4" shanks profile cutters, like a round over. I usually buy some rubber O rings at the hardware store and install them onto the shank and push them up toward the cutting edge, problem solved. JMHO.

    If you do have scoring on the bit, file them smooth. If let go, they will score the inside of the collet and continue to more damage to other bits and collet.
  8. Good advive here. An old cabinet-maker friend told me this long ago; I've been doing it so long that I forgot why. :p
  9. The Trend router bits we get over here have a nice feature to tell you how to install the bit:


    Im surprised CMT and others dont do this too.
  10. I think they call it frozen bit. It has happened to me at least twice, where the bit becomes locked into the collet even after its removed from the router motor and you have to force it out. A replacement collet is necessary and the manufacturers have always supplied replacement for free to me (Hitachi and Milwaukee).
  11. Hi.

    Yes they do.

    Wrong, if there's scoring on the bit, do Yourself a favour and throw it away. If any scoring happens while routing, throw the collet away too. Otherwise You'll be destroying every bit you have with the scored collet.

    The shanks can be ground and polished to specs if the bit is expensive. Rarely done, even in the industry.

    Collets can not be re-ground, especially on high-speed machinery.

    The table router operation is bad for the collet as people rarely clean out the fine dust from the collet grooves. Over the time the dust builds up, and the gripping capability is greatly reduced. Then the collet/bit is scored or the bit climbs.

    BTW, it's only wood, watching 20mm bit bury itself on steel is something You won't forget anytime soon ;).

  12. Are these new bits or perhaps a different brand than you have used in the past? I would think you probably had success for a while, and that this is a new problem. If you can measure the shanks with a micrometer or dial caliper, comparing "good" bits with the ones that are slipping, you may notice a difference in diameter. It might not take much to cause a problem. It actually may require a micrometer that reads in tenths (.0001) to notice a difference, if you can get your hands on one.

Share This Page

  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.