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I have posted this on a couple other forums so if any of you have seen it already I apologize you can just skip over it. It could come in handy for some of you others.


Ok so I have been trying to figure the way that works for me to make wooden knobs for a while. I love the look of wood knobs but I have never liked making them and always struggled trying to get them to look the way I want. I have seen people cut them with plug cutters, as well as turn them on a lathe and really neither method worked well for me. My main issue with both of these methods has not been turning a dowl, or cutting a plug but rather getting everything centered properly to drill for the pot shaft, and then countersinking it for the threads, nut, and washer of the pot.
Chris v has a nice and elegent solution to this problem, which many people have probably seen, where you simply get a forstner bit of the same diameter as your knob, drill a hole in a board clamped to the drill press and then insert the knob in the centered hole, where you can drill for the shaft and counter sink for the nut. If you have nice equipment this works really well, however most of my power tools are older than me and the drill press is no exeption. Because its so old the bearing are worn and its about like lighting striking the same place twice trying to do it this way. I also had issues trying to get the knob to seat down firmly and not spin once in contact with the bit. While I successfully made some nice knobs in this way I always ruined more than I made, and it was a frustrating time consuming process. This cuased me to look for a different method, and I settled on a variation of the plug cutter method that uses a hole saw.

I wanted to be able to cut my plug, drill the shaft hole, and countersink for the nut all in one motion. This requires a hole saw with a pilot bit that is removable( I used a one inch whole saw which cuts a plug just under 7/8). Other size saws will work as well and the beauty is that you can easily change between sizes offering you multiple knob diameters. I replaced the pilot bit with a 9/16 spade bit that I ground to look like this. the spade bit can easily be shaped with a belt grinder to get the correct shoulder and shank depths.





The nice thing about this method is that not only does it solve the problem of getting things properly centered (which is probably only a problem for me) but it also makes cutting knobs a lot faster. You don' have to set up anything special for a multi step process, and you don't have to change out through several bits and cutters for each knob. The hole saw also creates far less waste than a plug cutter does, which can make a big difference when you are talking about expensive exotic woods. The hole saw still works just fine as a whole saw, simply swap the original pilot bit back in.

this mehtod has worked really nicely for me so far, although I think I will make a new center bit from a 5/8 spade bit rather than the 9/16 which should give slightly better clearance around the larger nuts found on cts and some other pots.
this little tool only took maybe an hour or two make, and it really speeds up the knob making process. Its already saved me a lot of time, hopefully some of you will find it as useful as I have.

here you can see it all put together with the bit recessed in the saw. I set it so that it leaves about an eighth of an inch between the teeth and tip of the spade bit.

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~shad peters

http://www.flickr.com/photos/petersinstruments/
http://petersinstruments.blogspot.com/
http://petersinstruments.com/

I've been thinking about wood knobs. Thanks for the post. I have another method I'm gonna try though: Clamp workpiece to drill press, lower it enough to be able to change bits, lock it in place and drill in this order: Shaft hole, thread clearance hole, knob with plug cutter of choice. As long as nothing moves around, should drill pretty well centered I think.

I've yet to do it though... Gimmie three weeks.

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http://www.tinyhouseandland.com

yeah I'm sure that method will work quite well for you as long as you can keep everything centered and avoid chipping around the base where the walls are thin. Like I said there are many suitable ways to make wooden knobs, but for me with my setup this has proven to work very well. If you get where you are doing very many it is also a big time saver.

_________________
~shad peters

http://www.flickr.com/photos/petersinstruments/
http://petersinstruments.blogspot.com/
http://petersinstruments.com/

I used that exact method the last time I made wooden knobs. I had a bit of trouble with burn marks from the plug cutter on the outside, next time I'll have to be more careful about that, but other than that it works pretty well.

Noted.

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http://www.tinyhouseandland.com

I used my Taig mini lathe in the past to make a few wooden knobs. A lathe works great for this. But in the end I still prefer metal knobs over wood. I just like the look better.

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Another day, another dollar.

I used a hole saw for wooden knobs several years ago, seems like I remember that having the hole saw tangent to the edge of the work helped a lot with burning. If the outside of the kerf has an opening, the sawdust can escape. Just be sure the inside of the kerf is inside the edge of the work or you'll have a flat spot on your knob.

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A man hears what he wants to hear, and disreguards the rest. Paul Simon