20mm Router bit for MFT holes

Hi All,

I’m making an MFT top, using the Dominofix jig. It took me ages to find a 30mm router guide, I ended up buying it from Amazon.co.uk. I brought a 20mm Freud router bit on Amazon but then realized it’s not for boring\plunging.

Does anyone know where I can find a 20mm bit that is suitable? I could use a 1/2" bit and then route out the hole, but I’m going into laminate and I was to make sure the hole is really clean.



Any “hinge boring router bit” should work. They have a point in the center and spurs on the outside edge of the bit, so they are intended to plunge and leave a clean finish. The Festool version has an 8mm shank which is fine if you’re using a Festool router. If not, see if you can find a reducer to adapt it to your 1/2” router. The Festool bit is expensive but reviews I have seen indicate it leaves a nice finish but at $69, it’s pricey.

The other bits I see with 10mm shanks appear to Be for a drill or drill press, so don’t use those in a router even though you can get a reducer to make it fit. Router bits have much less run out so they can be spun up to the higher rpms seen in a router.

If you need to chuck an 8mm shank bit in your USA-market router - their are some choices that I know of:

Bosch Part # 3 607 000 645 for their 1617 router

There are probably others available for other routers.

Amana, Whiteside and others also make reducers to adapt a 1/2 inch collet to hold a 8mm shank:



Thanks all, I found a recommendation for this bit on the Festools forums. I think it has a 3/8 shank, which I can use in my Dewalt:


I spent ages looking for an 8mm collet but it was unclear if they work with a DW618. I am presuming the Porter Cable ones would…

That one doesn’t appear to be recommended for routers, but the 392.200.11 does. Amazon reviews don’t look too good though.

The bit you link to - is meant for the lower speed of a drill press or boring machine - not a router.

Dewalt and Porter Cable routers can be quite a bit different. When B&D acquired German toolmaker Elu in 1994 - it was the Elu designs that were morphed into Dewalt routers. Porter Cable was acquired by B&D ten years later in 2004. Since then some of the 2 companies routers are similar - like the Dewalt DWP611 and Porter Cable 450 - but others seem to be more distinct.

Thanks! I swear I picked the right one, I order that one as well and will return the wrong one!

FWIW the Bosch 8mm appears to fit the DW618. I don’t have any 8mm bits but I can’t see any issues…

Well that all works but with the Dewalt Plunge base I only get about a 1” hole :frowning:

My test template (created on a CNC) is 3/4” thick and I think I can get away with a 1/2” piece but that doesn’t get me through a 3/4” bench top and I was tempted to put 3/4” plywood underneath it! :frowning:

Hmm I think I figured it out. The Bosch collet is too big for the 30mm router guide. It was hitting that, not bottoming our the plunge router base. So I think I need to use the Dewalt 1/2” collet with a reducer. That should give me a bit more than 3/4” travel.

Plus if I can find a suitable piece of material that is 1/3” thick for my template I should be able to do a 1” hole…

You could try a collet extender - with an adapter sleeve mounted in it:


But if your 20mm bit is not long enough to cut the depth of hole you need - then the extension will not help.

Happy Christmas!

That works, I just need to find one with a collet outside diameter of 1” to get through the router guide. Or find an extension that only extends 1”.

This is too complicated :slight_smile: