One of the two things that frustrated me when I began turning was; first there was so little proper instruction on how to turn chair parts. The turning world is dominated by vessels. Second, the lathes on the market were designed with features to suit those needs. Where was a tool rest that was longer than 12" to be found? None of the manufactures even offered an optional one to purchase.
Fortunately the first complaint is being addressed. My chair making mentor and buddy, Peter Galbert, is doing a series of articles with Fine Woodworking that specifically gives proper instruction on how to turn spindle type furniture parts. Such as those found on chairs. See the first one of three here. You need to be a member to access it. Before this article I learned to turn by watching his Youtube videos on how to turn a baluster leg and it is totally free. A must see.
So I want to encourage you to get serious and make a long tool rest. I probably made this in about two hours and it has been well worth every minute. I didn't progress until I made this, really. It is worth it, do it, and don't look back.
Here are some photos of the inner workings. As alway, follow the rule of that, any shop apparatus should be of 10 parts or less, otherwise you are probably making it to complex.
First the part you actually rest the tool on would do well to be made of steel. Mine is 1/8 mild flat bar steel inset into the top edge of 8/4 hard maple, glued and screwed.
The tool rest is attached to shop made handscrew clamps that are used to fix the assembly to the bed of the lathe. I think a similar set up would work for most lathes despite the differences in bed dimension. I purchase only one handscrew clamp kit made by Jorgensen and split them up. The inside screw is just a threaded rod with nuts on both ends. They don't need to move once they are set to the bed thickness. Only the rear screw needs to open to adjust the rest.
I set the tool rest at about 20˚ to get the top close to the work while leaving me some room at the bottom from striking the bed. This also keeps the front edge of the body of the tool rest a bit back from the turning blank.
The rest attaches to the handscrew clamps via a bolt that passed through a slot in the rest and is treaded into a square nut housed within the end of the clamps. A square nut prevents it from turning in the mortis when tightening. I used a 3/8" bolt. The only improvement would be to make this function a quick release cam which I may eventually do.
There are some other things that will help you turn but this is a definite must have. Now get to turning! :)