Interested in building a larger MFT top using LR32 and OF1400. Which router bit works best? Festool 20 MM euro hinge boring bit (491072) or CMT 537.200.31 20mm Forstner Bit? I want to buy the bit that would allow a tight fit for my qwas dogs without any slop or play.
20MM Router Bit
- Thread starter cvn72
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Tim Morris
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Use the router bit. DON'T try and spin a forsner bit in a router, they are not designed to run at those speeds.
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Use the techique demonstrated in my Parf Dog video - you can use 20mm dowel instead of the Parf Dogs but look closely at the way I cut the holes. A complete table took less than 1 hour. You can use this method to make huge special size tables.
ONLY USE ROUTER CUTTERS IN ROUTERS
Peter
ONLY USE ROUTER CUTTERS IN ROUTERS
Peter
Already ordered festool 20mm euro hinge bit and some adjustable dogs from tool improvements website. Saw that spiral bit used by Peter's video. I'd rather use LR32 and OF1400 to get a cleaner and straight plunge cut. I'll just take my time when I do it. More concerned with accuracy than speed.
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Hi Sprior
When anything is replicated in woodwork the replicated object is never going to be identical to the original. However...
Just how accurate do the 20 mm holes need to be? If you drill 70 holes (I have forgotten how many there really are) then some will be plus error and some will be minus error. In theory there will be a little bit of cancellation of error. But, some errors can compound but the worst would be a doubling of the original error. If you look at a typical pair of holes North to South on the MFT and then a pair, East to West, at 90 degrees then the variation from square is likely to be small. Greater errors are introduced by the use of tall dogs (either Rail Dogs or Parf Dogs) or by operator error - such as putting lateral pressure on the saw or router during a cut.
So, in short, yes the replicated top is likely to be less accurate but not significantly so unless you are working for NASA.
What must never happen is the use of an MFT top COPY to be used as a pattern.
I hope this makes sense - it has past 6 pm here and 'the pubs are open' !
Peter
When anything is replicated in woodwork the replicated object is never going to be identical to the original. However...
Just how accurate do the 20 mm holes need to be? If you drill 70 holes (I have forgotten how many there really are) then some will be plus error and some will be minus error. In theory there will be a little bit of cancellation of error. But, some errors can compound but the worst would be a doubling of the original error. If you look at a typical pair of holes North to South on the MFT and then a pair, East to West, at 90 degrees then the variation from square is likely to be small. Greater errors are introduced by the use of tall dogs (either Rail Dogs or Parf Dogs) or by operator error - such as putting lateral pressure on the saw or router during a cut.
So, in short, yes the replicated top is likely to be less accurate but not significantly so unless you are working for NASA.
What must never happen is the use of an MFT top COPY to be used as a pattern.
I hope this makes sense - it has past 6 pm here and 'the pubs are open' !
Peter
The other issue is whether the act of copying your original MFT top will damage it. Since I don't have a Festool router (yet, someday) I don't have the Festool 20mm router bit as an option - I'm planning to use a 20mm forstner bit in a hand drill with a stand. I would assume that the router bit and forstner bit won't damage the holes being used as the pattern. I was a little less confident about the twist drill bit in your video - seemed like it could easily wear the sides of the MFT holes.
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You are right - care is needed. The drill I used is not too bad as it is designed for cutting in line with the axis of the drill and leaving clean sides. It does need to be kept upright - better achieved when not trying to make a video!
Peter
Peter
