I initially bought a router (this router) for some door hinge mortising. Now I need to route a few 1"x1" channels in some MDF. The 1" x 1 1/4" bit I need has a 1/2" shaft, but the collet on my router is only 1/4". Here are my questions:

  • Can I get a new collet that supports a larger bit?
  • If I can, should I? I guess I am thinking about torque and my router's engine here. enter image description here

3 Answers 3


If I can, should I?

I'm guessing that your idea is to make a single pass with the router set to a depth of 1".

For your project, I would not recommend the single-pass approach in MDF, or any analogous material for that matter, even with a 1/2" shank router bit with spiral flutes designed to clear the shavings out of the dado.

Instead I heartily suggest making several passes at increasing depths, removing perhaps 1/4" of depth or less on each pass. For this, a 1/4" shank 1" diameter carbide bit would be adequate if you dropped the bit into the collet as deeply as functional, perhaps pulling it out a ways, if necessary, for the final pass.

Better yet, hog out the bulk of each of the channels in several passes with a 3/8" or 1/2" diameter router bit, then make a final pass at full depth with your (still super-sharp) 1" diameter router bit to obtain your precise width and depth.

Hope this helps.

FWIW: I'd skip the rectangular tubing and router approach. I'd use flat stock and cut wide kerfs that are 1" deep using a long strait-edge clamped in place and a skill saw with a heavy (thick) blade that will cut wide kerfs (e.g. 1/8" wide kerfs).

FWIW #2: Whether you use lengths of tubing or flat stock, your door will still be prone to warping, even if you embed lengths of metal stock in multiple orientations. To counteract the tendency to warp, you'd need to embed a rectangular metal frame. ... or don't embed anything: use lockset hardware similar to that which is used with French doors. That hardware will secure your door at the top and bottom, keeping it flat.

FWIW #2a: If you don't believe FWIW#2, prove it to yourself by gluing some bamboo skewers in the pattern of your choice to a sheet of heavy paper. Once dry, you'll find that the paper is quite flexible (warp-able) even without bending the bamboo skewers.

  • Ha! It looks like I've been spamming SE too much with my soundproofing questions. I don't want to derail this question by discussing that too much, but I really think adding two or three 1"x1"x6' square tubes will keep it from warping. One of these tubes is rigid enough. Add one or two more and I really doubt the MDF will warp, especially when it's going to be screwed in from both sides. May 4, 2013 at 1:16
  • Also, I did see a 1"x1" carbide bit with a 1/4" shaft at Menard's today. I guess I will just have to go the two-pass approach like you said. I only need to go 1 1/16" in, so I'll do 1/2" deep on the first go then clear out the rest on the second. May 4, 2013 at 1:18
  • 1
    I understand about the square tubes being quite stiff, but their stiffness will not prevent your door from developing a twist. Anyway, happy to drop that subject. If it does twist, all you'll need to do to get a tight seal again is to R&R the door stops on the jambs.
    – mike
    May 4, 2013 at 1:40
  • 2
    I'd be very hesitant about routing out a 1x1 in just two passes with a 1/4" shank bit. I suggest at least 4 passes if using a 1/4" x 1" bit. One of the issues, especially with a light weight single-hand router and with a 1/4" shank, will be chatter, and the chatter will stress the shank possibly to the point of breaking. The chatter will be significant because the bit will be cutting both sides of the slot. Anyway, that's something to keep in mind, fwiw.
    – mike
    May 4, 2013 at 1:47
  • Ah, I see what you mean about the twist and I can actually see it. Good point. Thinking about it more, I don't even think putting cross supports at the top and bottom would prevent that unless they're welded together, something I am definitely not doing. I am making an adjustable door gasket, though, so that will help. I will also research ways to seal the MDF so it is not susceptible to moisture which, combined with the vertical supports, should definitely prevent warping/twisting. May 4, 2013 at 1:50

According to Fiasco Labs that router apparently doesn't have a 1/2" collet available for it, so this is kind of a non-starter.

But as a general answer, "palm routers" and "laminate trimmers" are small and good for hand-held work like edging and thin cuts, but aren't good at removing a large amount of material. It looks like your model doesn't have an adjustable speed, which is a good feature for using large bits. Larger bits means larger diameter, which means higher cutting edge linear speed for a given RPM. You want to run larger bits at a lower speed, to account for that.

As mike says, you don't want to do a 1" x 1" cut all at once. Take it slow. The suggestion to do several rough passes and then a single finish pass is a good one. If you have access to a circular saw, making several slightly shallow passes with that would also be an easy way to remove some of the material.


It depends on the size of the motor shaft, if it's large enough, Bosch will have provided a 1/2" collet as an available accessory.

In looking through the Bosch specs and accessories for the Bosch PR10E, they only show a 1/4" collet as being available which means the motor shaft size is too small to support 1/2"

At the speeds that these bits turn, having a large, well supported drive shaft is quite important.

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