Turning a Platter
Push your skills and create a showstopper.
The platter is probably my most favorite subjects to turn. The form is open and shows off the grain in the wood. On the outside, the beautiful double curve of the ogee and a rim that gently curves into the inside makes this piece aesthetically pleasing and ergonomic to hold. It’s also utilitarian.
Prepping the Blank
To start, I find the center of the blank using a pair of dividers or compass by scribing four arcs into the surface. Imagine a clock and scribe the arcs from 12, 3, 6, and 9 o’clock into the center of the blank, keeping the point of the compass on the outside points. When you make the four arcs, it will form a cross that indicates the middle.
Cutting the blank round on a band saw will make the initial balancing of the blank much quicker and easier. Even just cutting the corners off to make an octagon will be far faster to turn than from square.
Mount the Blank
There are several ways that the blank could be mounted on the lathe. I use a screw chuck for diameters up to 12". For blanks larger than 12", I prefer to use a 6" faceplate. This gives me more support when turning towards the outside of the platter.
When the blank is mounted securely, make sure that the blank is tight against the face of the screw chuck. I start with the speed approximately 1600 to 1800 rpm. The speed you can turn at depends on the blank being used. For example, if the blank has half sapwood and half heartwood, there will be a harmonic and vibration due to the different densities within the blank. As a guide to speed, I prefer to turn as fast as I feel safe, without any vibration.
First Cuts
Using a 1/2"-long grind bowl gouge, I proceed to true up the outside edge of the platter using a push cut with the bevel “floating” behind the cut, but in contact with the wood. Then, I true up the face which will become the bottom of the platter. I do this with a draw cut—drawing the tip of the bottom wing of the long grind bowl gouge towards me. I do this until I have a clean, flat face on the blank. With the blank now true on the edge and face I prepare a recess that will house dovetailed jaws in a chuck. This will hold the platter when turning the rim and hollowing out the platter.
I measure the diameter of the chuck jaws with dividers and transfer the measurement to the wood. To make the recess, I use a parting tool to make two or three plunge cuts into the blank, side-by-side. These are about 3/16" deep. This leaves enough room to get a bowl gouge in there and remove the rest of the waste. The inside of the recess needs to be slightly dovetailed, and I do this with a parting tool ground at 10° to match my dovetail jaws. Be sure this cut is clean and accurate, as it makes a huge difference to how true the platter will run when remounted.
Creating the Foot
The full diameter of the foot is approximately one-third of the diameter of the platter. From the outside edge of the foot, I make a cut with the parting tool about 1/16" deep, and then remove the excess 1/16" wood from the foot to the edge of the platter. This defines the foot and is the final thickness of the foot when the platter is finished.
An Ogee via Geometry
An Ogee is easy to create via geometry. It’s simply a sine wave after all. I start by making a few layout lines to follow as I turn. Divide the area between the foot and rim into thirds. The finished rim is about 1/8" thick. I mark this rim thickness with a pencil line about 3/16" from the back face. This extra thickness allows extra for any changes in the curve that may be necessary. Remember, you can take wood off, but you can’t put it back on!
Now that I have the reference marks, I use a draw cut from line closest to the foot to the rim line.
Here, I’m making a simple flat to remove the bulk of the waste. Once the flat is made, I use a push cut to from the first part of (the hollow) of the Ogee curve. This cut is from the rim towards the foot and is against the grain. Yes, I cut against the grain. I do this because it allows me to cut in a position where I can see the profile develop and allows me to see the curve I am cutting. This is a push cut so remember to ride the bevel.
Finished Ogee
After the flat has been formed into a soft curve, I mark a pencil line at the halfway point between the outer edge of the foot and the rim of the bowl. This is the “inflection” point of the sine wave and where one curve transitions into the other. You can see this in the drawing.
Then, using a draw cut with the grain and again looking at the profile whilst cutting, I remove the waste wood from the high point left after the initial curve cut. These cuts will extend out to the edge of the platter in order to remove any “tear out” from cutting against the grain when forming the initial curve. This is the reason for leaving the extra thickness towards the rim. It allows for these clean up cuts. Here, I prefer the draw cut as I can take off hair-like shavings when refining the ogee curve and I am also in a position where I can look at the profile whilst cutting. A light shining on the edge of the platter allows me to see any high points and refine them.
To determine if the Ogee curve is correct and balanced, I replace the pencil line and then look at the profile closely. I am looking to see if one curve is exactly the other but just opposite and 50/50 in proportion.
Finish the Back
Now on to sanding and finishing. Many turners have their own preferred finish and there are so many products out there that it can be very confusing. The finish I use is very simple and look great.
Depending on how good a finish you get from your finishing cuts will dictate the grade of grit to use first. I usually start with a 180 grit and work through to at least 400 grit, maybe finer if the wood requires it. The sanding speed of the lathe is anywhere from 500 to 900 rpm. I like to power sand, and generally use a 2-inch sanding pad and electric drill. Again, there are many on the market and I have tried several brands some of which are better
than others but tend to gravitate towards the “Skilton” brand sanding pad, which I have used for well over 20 years now. They’re available in
1, 2 and 3-inch diameters and are designed to be used with Velcro-backed discs.
There is some discussion amongst woodturners tat sanding against the grain by turning the lathe in reverse will give you a better finish. I have never found the need to do this as I tend to like to raise the grain between sanding grits with either water or denatured alcohol.
After sanding, I apply a liberal coat of sanding sealer. My mix is 70% Zinzer’s wax-free shellac mixed with 30% denatured alcohol. I find that this diluted mix is drawn further into the pores of the wood and after the first coat is dry and the second applied and dried the wood, it will be sealed for an application of natural Danish oil. After wiping a coat of Danish oil, I let it set for a few minutes before wiping away any excess. I’ll let the surface dry and apply as many coats as I feel necessary letting each one dry in between to give me the depth and sheen I am looking for.
The number of coats you’ll want to apply depends on the density of the wood and the figure. When the last coat is applied and fully cured, I buff the surface with a soft lint free cloth. If sanded and finished correctly, you’ll have a deep sheen and the oil will emphasize the grain and chatoyancy in the wood. It’s a beautiful silky-smooth sheen.
Remount the Platter
With the outside finished, the platter is removed and remounted in the dovetail jaws. The dovetail jaws slip into the recess and you can open the chuck to expand the jaws, holding the platter in place. Make sure that the platter turns true and square. If it doesn’t and it wobbles, you’ll have an uneven thickness on the rim. With the platter held in the chuck, the face can now be trued up and turned to the thickness desired for the rim. Again, I use a draw cut find it easier with more tool control to draw the tool towards me rather than push it away. There’s a reason Japanese saws planes work in the same manner!
When you have trued the face and turned it down to the desired thickness, we can now work on the rim itself. I create the rim at this stage in particular, because it’s possible when you start to remove the waste from the center of platter that tension and stress will be released within the blank. This can cause the platter to move slightly, becoming warped or oblong. If the platter moves, it’s difficult to sand a rim evenly when the rim is running out of true!
Make the Rim
My preferred proportion for the rim is that it’s a third of the radius of the platter. The rim itself is also not flat– it has a slight curve and is angled in towards the hollow of the platter.
After making out the rim width, the rim itself is divided into thirds again. The outside third is turned away first, using a draw cut. Here, you’re looking for a slight curve towards the outside of the platter, with the pencil line being the high point. On the inside edge of the rim, use a push cut towards the center to turn the inside two thirds curving down towards the center.
The design of the rim is intended to do two things. Aesthetically, it draws your eye into the piece. But, it’s also ergonomic as well. As you hold the platter, your thumbs rest on the curve and it feels “right”.
Once the rim has been turned and shaped, I sand it and apply sealer so that it’s ready for the Danish oil finish later.
Now, on to the Hollowing
As I mentioned before, I prefer the rim to be approximately a third of the radius. To give me a defined starting point for hollowing, and a clean entry cut, I use the parting tool to make a small groove where the rim transitions into the hollow. This will also allow for the bevel of the bowl gouge to rest on it when cutting away from the rim into the middle of the platter.
I start hollowing from the middle and go as deep as the hole left by the screw chuck, then work my way out to the edge of the rim of the platter. This technique leaves some material in the middle that
supports the platter, whilst getting the first half of the hollowing done. Where the inside edge of the rim meets the hollow, I make a small undercut with a 3/8th micro bevel bowl gouge. This leaves a very pleasant, ergonomic feel to the platter. When I am happy with the lead in curve from the edge of the rim to where I had previously hollowed, I continue to remove the rest of the waste wood working the bowl gouge from the outside into the middle. This cut is in the direction of the grain and, if your gouge is sharp, leaves a nice finish.
Be aware that the platter is being held in a recess and that the leading curve into the platter does not go too deep. If it does, your last couple of cuts can enter the recess and leave you with a hole in the platter! If you need to, you can use a curved scraper to refine and blend any high spots on the inside of the platter.
After the inside is completed, I sand and finish the inside curve in exactly the same way as the outside working through the grits of abrasive, sealing and then a light coat of Danish oil.
If all goes well you should end up with a beautiful, ergonomic, aesthetically pleasing utilitarian platter!