No! That’s a mandrill! I’m talking about a mandrel, which is, according to Oxford, a “cylindrical rod around which metal or other material is forged or shaped”. Well, in this case, we’re making a mandrel for pastry crust, so we’re not likely to be forging anything. If you are forging pastries, you’re doing it wrong.
But this example is for little quiches or tortes that have a very thin crust. The more uniformly we can form this crust, the better the result will be. This same principle has been followed in dies and patterns. You make the reverse of what you want to stamp or cast the shape of what your end result should be. We need to start by taking some measurements.
That’s the pan we’re using. Since the pastries are small, I need to account for a 1/8″ crust. If they were larger (like a normal muffin tin), I would size it to accommodate a 3/16″ crust on account of the greater weight of the filling. My Starrett dial calipers on the right are my trusted companion when it comes to this kind of measurement. I can use the inside jaws to get the top diameter, but the bottom is out of reach. So I use a set of inside calipers (middle) to gauge the diameter, then read it out as a measurement using the dial calipers. Finally I get the depth using my combination square.
Once I have measurements, IT IS VERY IMPORTANT to account for the crust thickness before you start cutting. The side measurements need to be reduced by two crusts, and the bottom by one. This will give you finished size of the mandrel.
Centre up your blank in the lathe and start cutting a groove close to the major diameter, at the distance your depth needs to be. Remember to leave a sacrificial stub.
Once you’ve gotten there, you can cut the minor diameter at the bottom, and rough in the taper. I have no idea what the angle is. It’s irrelevant. If the top fits, and the bottom fits, and it’s a straight line between them, I don’t need to try to measure the angle.
When the rough turning is done, you’re going to have to start nibbling. I like to use a square edge scraper. Measure frequently with your dial calipers, and leave it a few thousandths oversize because you’re going to sand it later. If you need to cut back the handle portion so you can fit your scraper in there, that’s fine, but don’t cut too far back into the handle area or it may impinge on the knob.
Now put a knob on the top so your baker can use it.
Sand on the lathe. Cut off the drive stubs and round off the knob. For truing the bottom of our mandrel, I’ve found it easiest to run it over a piece of sandpaper on glass.
A swipe of finish, and our mandrel is complete! It should give your resident baker consistent crusts every time.