It was raining again in Sunny Brisbane and I was bored with PC based woodwork so I decided to test out a few posts regarding making square wood round.
So I set up in the garage doorway,.... the nice white canopy you saw I had in the previous moulding blogs was destroyed in the wind, as I put it in the rubbish I saw a note “Do not use in strong wind”, a little bigger or more obvious would have been nice!..anyway…
Just about all the router based blogs I read had the material being profiled static and the router being moved over the stock, this if not obvious it allows the fence to remain on the timber from start to finish, not something that’s possible with a router table or shaper as they (or at least mine does) only have short fences.
All information showed an end index piece remaining at the end for stability.
So knowing this I started with short pieces then advanced to longer lengths, surprisingly I did not get any real differences however needed to ensure the “square end” entered the table as it completed its radius. As the profile is round, does it really make and great difference I thought not.
I had some recycled pine planks so I decided to use them.
I used a table saw to rip the planks
A shaper fitted with a 3/8” 9.25mm bearing mounted round over bit
Some 80 Grit to remove the hairline grooves
A pair of calipers to measure the resultant “roundness”
To make a round stock I calculated to stock would have to be 18.5mm x 18.5mm
I ripped the planks down to the required dimensions of 18.5mm x 18.5mm, the off cuts I used to make the half round stock.
The information I read had the timber being thicknesses to the required thickness after sawing, but as this activity was just keeping me entertained I didn’t get any more machines out, and profiled them from sawn only.
I mounted the router bit up gave the little fella its drop oil and checked it was OK.
I then used a test piece to set up the router bit height.
Once I was happy I was getting the correct profile I then moulded the four sides.
I marked an index spot on the fence to start the profile and repeated this on the other four sides, stopping at a predetermined location before the end.
My initial measure ups were conducted and with a couple of fine tuning adjustments made, then it was simple a matter of profiling all the prepared stock finishing with the off cuts for the half round sections.
You may notice the dowel sitting between the calpers jaws has a square section on it. This was a early run I made in two sections.
I then sanded them all a 80G simply to remove the “fur” and hairlines from the edge of the router bit and they were ready for final checking.
As I sanded them they felt round to me, or at least very close, so I was reasonably happy with the physical results.
This is what I saw when I cut their heads off.
It looks like there is a couple if klinkers amongst them, but generally reasonable
When I ran the final off cuts through to half profile them they were most suitable so I called it quits for the afternoon.
The final measurements produced errors of up to 0.2mm difference, so I checked the ends and saw a similar error there. (hence the thicknessing step is required I guess)
As the error in squareness was present and carried on into the roundness this partially explains the differences.
Considering I did not thickness the timber any more than with just the table saw I considered it to be an acceptable result as an experiment at this stage.
So next time:
I have a 3/4” round over bit so I will go looking for material approx. 40mm x 40mm and this time will thickness them to size to see if there is any noticeable difference.
Stay tuned for more rain activated brainstorms !
-- Regards Robert