Surfacing with a router

[Deadeye]

I have some slabs too wide (and unwieldy) for my planer, so I built a sled for my router (DW624).
However, at fully plunged, the bit is only 16mm below the foot of the router...and the sled is 18mm thick.
So I bought a Trend collet extender (1/2" collet and 1/2" surfacing cutter) - and it's completely unusable - it vibrates fit to burst and wrenches the router around even when not in contact with the wood.
I know the issue isn't the router or the cutter - if I take off the extension, it all runs fine with just the cutter, I just can't use it through the floor of the sled. Similarly, the extension without the cutter runs rough as old boots (slightly less bad because there's slightly less mass but still awful)

Any advice? Is it possible to rebalance these things?

 

[alex robinson]

Would doubt it. This may sound silly, but have you tried taking it out and putting it back in again? I have to use an extension with my sled and sometimes it doesn't sit right and shakes terribly.

I have used cheap ones off Amazon. https://www.amazon.co.uk/Gasea-Rout...9&psc=1&mcid=25a35d92236738ccb99a852597ae8cda
Managed to bend one with a really bad catch, but at £10 it doesn't really matter.

 

[Sideways]

It's not fit for purpose. Send it back.
Have a look see if there is a musclechuck.to fit your router instead. It is a stronger design.

 

[Peter Sefton]

You could try the new Musclechuck universal extension, fits any 1/2" router and gives an extra 30mm of reach. Really pleased with it, even better than the old Xtreme Xtension with Musclechucks noose like grip.

The fitting instructions need to be followed to ensure its balanced but only takes a couple of minutes to do.

https://woodworkersworkshop.co.uk/musclechuck-universal-extension/

Cheers

Peter

 

[MF1000]

For decent surfacing you need a spill board cutter running at the lowest speed your router will go. I use an extension with mine and there is vibration etc but it’s still controllable. Bonus of the spill board cutters is that they have replaceable cutting tips

 

[imageel]

@Deadeye - check out my recent thread on a workbench build - I surfaced a 2m x 740mm hardwood benchtop using a router sled and it performed pretty well with only marginal tear-out on the cutter edges and nothing that couldn't be cleaned up with a finely set block plane and a scraper.
I used a 35mm dia bottom trim cutter from Wealden and that had a 21mm deep head but from memory the sled was made from only 6mm ply, but stiffened by ply webs and some hardwood stiffening strips placed alongside the outer edges of the router base running track.
I daresay I could have made it a bit stiffer to reduce the breakout I experienced, however in reality it wasn't that bad to clean up afterwards.
It's unclear to me why 16mm of stick-out below your sled is insufficient to do the job, surely you perhaps just need to lower whatever standoffs you are running on your guides to lower the sled height over the worksurface.
..Unless I'm misunderstanding what you are trying to do,
/Ed

 

[imageel]

If of interest I am selling up so the largish router bit I used, a Wealden T2148½ is yours for £20 shipped, can post pics of it, aside from the top it has been little used but has some minor scuffs on the upper non-cutting face where I accidentally released the plunge on the router whilst still running - it doesn't fit through the router base aperture......
PM me if of interest
/Ed

 

[Deadeye]

@Deadeye - check out my recent thread on a workbench build - I surfaced a 2m x 740mm hardwood benchtop using a router sled and it performed pretty well with only marginal tear-out on the cutter edges and nothing that couldn't be cleaned up with a finely set block plane and a scraper.
I used a 35mm dia bottom trim cutter from Wealden and that had a 21mm deep head but from memory the sled was made from only 6mm ply, but stiffened by ply webs and some hardwood stiffening strips placed alongside the outer edges of the router base running track.
I daresay I could have made it a bit stiffer to reduce the breakout I experienced, however in reality it wasn't that bad to clean up afterwards.
It's unclear to me why 16mm of stick-out below your sled is insufficient to do the job, surely you perhaps just need to lower whatever standoffs you are running on your guides to lower the sled height over the worksurface.
..Unless I'm misunderstanding what you are trying to do,
/Ed

Thanks - will take a look. The 16mm protrusion is a problem because my sled is 18mm ply! I will build another with a thinner base and rely on the side rails to stiffen I guess.

 

[Ollie78]

Sounds like its not seating right or its a Friday afternoon special, they should send you a replacement.
I recommend one of these bits https://www.scosarg.com/cmt-cnc-spoilboard-surfacing-router-z3-s-12-d-35
So much better than any I tried before for surfacing.

 

[MF1000]

They aren’t cheap but it’s like a knife through butter with a properly set up cutter like the one Ollie referenced