20mm Router bit for MFT holes


#1

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.

Thanks

Ben


#2

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.


#3

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:

https://www.toolstoday.com/v-5551-rb-118.html?glCountry=US&glCurrency=USD&ne_ppc_id=229790000&gclid=EAIaIQobChMIkoXIo9Sz3wIVg8DICh3ldggREAYYASABEgLtF_D_BwE

https://www.ebay.com/p/Whiteside-Router-Bits-6400X8-Steel-Router-COLLETS-With-8mm-Inside-Diameter-and-1/28012070173?iid=272024072767&chn=ps


#4

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:

https://www.amazon.com/CMT-317-200-11-Diameter-Right-Hand-Rotation/dp/B000P4JIMM

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…


#5

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


#6

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.


#7

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


#8

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


#9

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:


#10

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…


#11

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

https://www.mlcswoodworking.com/shopsite_sc/store/html/smarthtml/pages/router_collet.html

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


#12

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: