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Gerbilsquasher
8th Aug 2010, 04:44 PM
I play around with metal more than wood but since working in engineering I seem to be expecting some very high accuracy from my woodwork as well!

In the past I have laid a floor using recycled Tas Oak floorboards. I have also used these floorboards for a very attractive wall lining for my shed office, running a router down the tongue side to leave a 10mm groove when joined together (now they look less like floorboards!).

The wall lining I sanded back with a belt sander and/or a sanding disc on an angle grinder (speed slowed down with speed controller). Thickness wasn't important. The boards for the floor job were cleaned up using my Wolfenden buzzer, after removing all nails and staples etc. (or so I thought, but that's another story....)

To my dismay the boards, when laid, were all different thicknesses and the entire floor had to be sanded again mostly with hired floor sanding gear. It may sound stupid but obviously I was caught out by the boards coming from different sources. Regardless of the extra work, however, it has come up looking awesome, and it is something I want to try again in our new house.

I have been considering the purchase of a wide belt sander rather than a thicknesser for the next time. The Wolfenden buzzer is a great machine and did a great job but there was some waste to the floorboards, especially those with twisty grains where the buzzer pulled out chunks rendering the board useless. Of course the twisty grain would have made the floor more interesting. Or was I doing something wrong? At most I was only trying to take off perhaps a mm, more often a lot less.

My conclusion was that if I could sand and equalise the thickness of the second hand floorboards in the same operation it would not only save time but there would be less variation in thickness when I nailed them down, meaning less sanding once laid.

I am a bit shy of a thicknesser because it might remove chunks like the buzzer did. Will the wide belt sander do the trick? Do they have feed rollers? Spending a few grand and availability of 3 phase is not an issue, so I would be looking at a used industrial machine rather than something from Hafco. I also have plans to use floorboards for other things so it will be used more than once.

Like I said, I've worked a lot more metal than wood. With wood you can't weld a bit back on if you cut it too short! :wink:

elanjacobs
8th Aug 2010, 05:52 PM
One thing you need to bear in mind is that buzzers are designed to REMOVE a specific amount of material, thicknessers and wide-belt sanders are designed to LEAVE a specific amount of material; so if your rough boards had 10mm variation in them to start, buzzing a few mm off each one will still leave you with a 10mm difference.

Curly grain is an issue for pretty much any tool with spinning blades, but a slow feed speed (with the grain as much as possible) combined with sharp knives and shallow cuts should get you a fairly clean surface. Ideal would be a "helix" type cutterhead; they leave a surface almost good enough to polish in almost anything but they're horrendously expensive in an industrial machine (Holmesglen TAFE in Chadstone had 2 630mm thicknessers converted to helix cutterblocks at a cost of about 10k EACH).

WBS's are not designed to remove large amounts of material (max 0.5mm per pass) and you'll find that dressing rough timber to size with one will be both painfully slow and cost an arm and two legs in sandpaper belts.

Long story short, I'd get a good second hand thicknesser with no less than a 3-knife cutterblock (4-knife is vastly superior) that's able to feed as slow as 5m/min (20ft/min). The older Wadkin and SCM machines are pretty much bomb-proof - our SCM thicknesser at work hasn't missed a beat in 60 years.

Gerbilsquasher
8th Aug 2010, 07:17 PM
One thing you need to bear in mind is that buzzers are designed to REMOVE a specific amount of material, thicknessers and wide-belt sanders are designed to LEAVE a specific amount of material; so if your rough boards had 10mm variation in them to start, buzzing a few mm off each one will still leave you with a 10mm difference.

I am sure that most if not all boards were buzzed with the same depth. Obviously different batches of boards have different thicknesses. If building a new house, all boards would be very similar, second hand boards could come from various suppliers.

If I had gone to the trouble of batching boards based on thickness I would probably have had fewer dramas.


Curly grain is an issue for pretty much any tool with spinning blades, but a slow feed speed (with the grain as much as possible) combined with sharp knives and shallow cuts should get you a fairly clean surface. Ideal would be a "helix" type cutterhead; they leave a surface almost good enough to polish in almost anything but they're horrendously expensive in an industrial machine (Holmesglen TAFE in Chadstone had 2 630mm thicknessers converted to helix cutterblocks at a cost of about 10k EACH).

In milling (metal) terms a slab mill would be very similar in design, and most likely price!


WBS's are not designed to remove large amounts of material (max 0.5mm per pass) and you'll find that dressing rough timber to size with one will be both painfully slow and cost an arm and two legs in sandpaper belts.

Long story short, I'd get a good second hand thicknesser with no less than a 3-knife cutterblock (4-knife is vastly superior) that's able to feed as slow as 5m/min (20ft/min). The older Wadkin and SCM machines are pretty much bomb-proof - our SCM thicknesser at work hasn't missed a beat in 60 years.

Thanks for the excellent advice and naming a few brands to look out for.

BTW should you ever be in the market for a milling machine i wouldn't go past a Cincinatti:wink:

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