Stripped threads in BT3000 motor bracket - looking for a fix

This topic is closed.
  • Filter
  • Time
  • Show
Clear All
new posts

  • Stripped threads in BT3000 motor bracket - looking for a fix

    After cleaning/polishing my BT3000 shims I stripped one of the 10-24 screws and the threads in the motor bracket. In the manual see that the motor bracket doesn't have a separate part number... it's one assembly. I sure hate to buy a complete assembly if there's another way to fix things. I thought about trying to chase the threads in the aluminum bracket but I'll bet they're too chewed up. Another idea would be to go one size up but I think a 12-24 will be too large as would a M6. Any ideas would be appreciated.


  • #2
    Is there enough material for a helicoil?
    Please like and subscribe to my YouTube channel. Please check out and subscribe to my Workshop Blog.


    • #3
      I don’t recall how the motor bracket buggered up nut looks. Is there enough metal left to drill the bad thread and insert, as dbhost stated, install a helicoil? Is there enough metal in the nut to drill it out to the 13/64” for a 10-24 helicoil?

      Can you drill it out and put a nut on the back side?

      I’ve used quite a few helicoils with some success. They are relatively easy to install but the smaller size such as this are easy to mess up. When properly installed the biggest problems come when removing the bolt and having the helicoil coming out, or rather try to come out.

      Instead of helicoils I now use a simular fastner repair known as Rivnut, tirxnut, blind river nut, snug fastener, and numerous other names. They work like a pop rivet and are for sheet metal and plate applications and are intended to be installed in a blind situation, but do work in thick metal in a drilled hole. If you intend on keeping 10-24 screws, my suggestion for this repair using a rivet nut would be drill the stripped hole out with a 7mm drill then tap it with a 8 x 1.25 tap, then drill into the new threads with an19/64 bit ( the recommended drill size for a 10-24 rivet nut. Then finish by seating a Rivnut flush. This should last until someone overtightens it. 10-24 is not rated at much torque, especially in au. HF stocks a rivet nut kit with a tool and a supply of rivet nuts, it’s an ok tool suitable for occasionally use.


      • nicer20
        nicer20 commented
        Editing a comment
        Do you mean Harbor Freight? As a curiosity I looked up Rivnut on HF site but can't locate any product. Thanks in advance.

      • woodturner
        woodturner commented
        Editing a comment
        I get the reasoning, but tapping the Rivnut hole removes material that the Rivnut compresses against when installed, and will make it more likely to pull out. Since they work by expanding against the sides of the hole, a smooth drilled hole is likely to hold much better. It would be interesting to see a comparison test to confirm this.

      • LCHIEN
        LCHIEN commented
        Editing a comment
        Nicer20, RivNut is a trademarked product, an expanding nut insert.

        There are many Riivnut uses. Using rivnuts is easy & can be installed in seconds. The one-piece blind nut insert provides a nut plate. Contact (800)236-3200

    • #4
      Thanks guys... I will look into the Rivnut and helicoil fix. A few Rivnut-fix questions though; why drill-tap-drill... why not just drill 19/64? Next, the motor bracket hole is ~ 3/4" deep and not thru-hole. There's no room for a nut behind and I'm unsure how the Rivnut 'swage' would be affected since it will expand in the hole and not behind the hole as it would with sheetmetal. My last concern would be the Rivnut flange - the shim would only contact the Rivnut flange and not the ~4" motor bracket face (although this is just a thin edge). I'd also need to install Rivnuts on all four holes so that the motor bracket would have four equal height points of contact.. so to speak. I'm surprised that the Ryobi screws (two of them, not just one) were stripped by the aluminum. They must be very soft. Both screws were stripped at the same point along the length and both are the top-most located. I tightened all four screws down a bit at a time to ensure that the motor shaft bearing was being pressed into the motor guide bracket parallel. Not sure how things went bad Those two screws only got hard to turn as they neared the bottom so I am very surprised I cross-threaded them but the force needed to get those last threads in were sorta excessive. Next time I'll use a bit of anti-seize on the screws.

      After some thought, I think a helicoil fix would be a good idea. There would be no flange and with Red Loctite it likely won't back out. I will chase the threads in the motor bracket just to get a feel for the damage though.

      Thanks again for your suggestions!



      • capncarl
        capncarl commented
        Editing a comment
        The reason I put a light tap on a hole for a rivnut is purely for grip. It probably isn’t necessary on a small insert like this but you don’t really want to have to dismantle the saw again for this problem. These Rivnuts are totally inside the hole and have no flange, so no worry about height, and you don’t want to mess up something that isn’t broke. The rivnut is a 2 piece fastener where the threaded piece outside is tapered and is pulled inside the top piece, expanding it inside the hole, just like a concrete expanding anchor. A major benefit of this kind of fastener is that if it slips inside the hole it will pull against the motor flange and will retighten itself and not fail.

        If you change from 10-24 to a 12-24, I think the tap drill size is still smaller than the tap drill for a helicoil or a rivnut. I can dig out my machinist handbook if needed.