Ron's Brain Dump

Supported spindles call for a serious taper at the end opposite the whorl; ideally it's also quite smooth since this is the spot most in contact with the spinner's fingers and thus can cause wear and tear on the user over many hours.

Supported spindles also might need to be a bit lighter and shorter than the average suspended spindle tho this might also be a user preference and Navajo-style supported spindles are quite large (designed to be used while seated and supported by the floor). So mostly we're talking about table-top (or lap-top) supported spindles here.

Supported (and bottom-whorl in general) spindles don't have a whorl notch since the fiber is all above the whorl and thus there's no need to further “bind” it to the spindle.

These are ideally small heavy bowls with fairly flat bottoms to minimize sliding with a hollow that is a simple inverted cone (not a semi-spherical shape like regular bowls). This gives the point of the spindle a good registration at the center of the bowl and keeping the cone shallow minimizes the chance of the whorl hitting the bowl edge when it's tilted during use.

The measure of quality of a supported spindle is how long it'll spin on a single go; ideally 30 seconds or more in the hands of an experienced spinner. This is, of course, a function of weight, balance, and the quality of the point and support. Some makers put a bit of metal (ball-bearing, rounded wire, etc) at the point to minimize wearing and friction between the spindle and the support. A heavy oil wooden support bowl also helps here to minimize friction and wobble in the spindle.

Suspended spindle shafts can be anywhere from 8-12“ long, straight or tapered (tho not as tapered as a supported spindle). Tapering the shaft helps with balance because it lets the turner support the spindle between centers and balance the shaft material around the axis of the lathe. Un-tapered shafts (i.e., whole dowels) are more at the mercy of the dowel being balanced and also tend to look a bit cruder (IMHO).

Suspended spindles typically have a hook above the whorl to hold the fiber to the spindle (it can also be done with a half-hitch knot but the hook makes life easier). I believe the best hook shape is a tear-drop hook with a slight back lean so that the fiber is placed on the axis of rotation regardless of whether it's the first spinning (where the fiber is simply hooked to the top of the spindle) or subsequent spinnings (where the spun fiber is gathered into a cop below the whorl and the trailing end passes thru the notch and into the hook which tends to pull the fiber towards the notch).

The two most common ways to make a hook are using cup-hooks (looks tacky to me but some spinners like them) or shaping a metal wire. So far I prefer 16 gauge stainless-steel wire cut to 2” length and then glued into a 1.4mm hole with thin CA glue. Ideally the hook is shaped BEFORE the wire is attached to the drop-spindle so that flexing the wire doesn't cause it to come loose from the CA glue. Repair is easy so long as the spindle itself isn't damaged but it's still a PITA to have to re-glue the wire. Shaping of the wire seems easiest with round mandrel pliers that make the hook shaping easy. The trick is then getting the right back-bend. The hook is then dry-fitted to the spindle until the length looks right and then glued in place. Note, the hook must face towards the lightest side of the whorl so that the notch can be placed behind it to move the balance back to axis/center. (see below)

Suspended spindle whorls also typically have at least 1 notch behind the hook to further increase the force the whorl can put on the fiber (otherwise it can slip around the whorl and not twist at all or very little. The notch is also used to balance the spindle by removing weight from the whorl on the heaviest side (found by placing the nearly completed spindle on a flat level surface and seeing in which way it rolls and where it stops - the bottom of the whorl when it stops is the heaviest side and thus where the notch should be). Notch depth/width can be adjusted to help compensate for the off-center weight up to a point. Multiple notches is also an option tho I haven't tried that yet. It's also possible to add a counter-weight to the light side of the whorl to bring the balance point closer to the axle; I haven't tried that yet either tho I have ideas on how to calculate the amount of weight and, thus, the amount of metal that would be needed to improve the balance. Still some research to be done in this area.

Suspended spindles can have straight shafts or tapered; I've started making more tapered shafts to make it easier to balance the spindle by removing dowel material further from the axis of rotation (of both the spindle and the lathe on which it's being turned). It's also more visually pleasing along with a dull point at the tip (don't make it too sharp, tho - if the spindle is dropped, and it very likely will be several times, pointy tips can break off).

Some suspended spindles also have grooves on the lower 3rd of the shaft to improve grip; this is also an area I have yet to investigate but will soon. One thing I have learned is that the grooves should be carved/cut rather than scratched which, while it textures the shaft, also makes it very unpleasant looking and to the touch. One thought is to carve these on the CNC (tho that seems a bit excessive); another thought is to hand-carve these with a V-chisel after marking them evenly around the shaft using the indexing wheel on the lathe. Obviously removing this material is likely to impact the balance of the spindle if the grooves are not all of equal width, length, and depth.