Door Knobs

[custard]

I've been asked by a client to turn some cupboard door knobs in a specific timber to match some furniture I've made that will sit elsewhere in the same room. The knobs are about 55mm in diameter and about 40mm long, they're to be secured to the cupboard doors with a screw.

My turning skills are pretty basic so hopefully someone here can give me some pointers!

1. For something of these dimensions would the grain normally run across the door knob (i.e. like a bowl) or along the door knob (i.e. in spindle turning fashion, which is how I'd normally turn a small drawer pull)?

2. If the grain runs across how would you mount it in the lathe? My only screw mount plate has a screw which would leave too large a hole to take the mounting screw on the cupboard door.

Thanks

 

[woodfarmer]

Most doorknobs are turned as in spindle turning because it is easier to do. The problem is the screws then tend to cut the end grain and fall out.

it is your choice

 

[andygc]

Most doorknobs are turned as in spindle turning because it is easier to do. The problem is the screws then tend to cut the end grain and fall out.

I don't think that's true. Go to any branch of B&Q or Homebase, look on eBay, or visit any supplier of kitchen cabinets. All the wooden knobs are cross-grain.

You could make your own screw chuck with a screw smaller than the one you want to use to attach the knob. Turn a hardwood disc to fit a chuck, drill through on the lathe to make sure you put the screw in the centre, put the screw through, with a drop of epoxy under the head if you like. One screw chuck which should last for a batch of knobs.

 

[custard]

You could make your own screw chuck with a screw smaller than the one you want to use to attach the knob. Turn a hardwood disc to fit a chuck, drill through on the lathe to make sure you put the screw in the centre, put the screw through, with a drop of epoxy under the head if you like. One screw chuck which should last for a batch of knobs.

Good tip, thank you.

 

[Phil Pascoe]

I would epoxy some threaded bar into the knob, and bolt through the door. You could counterbore and plug the back if you wished. The knobs with screws always seem to end up pulling out, although you could always glue under them when first screwing them in which would help stop them unscrewing.

 

[Random Orbital Bob]

I turned two oak knobs for my front door last summer and I also did them cross grain. All I did to mount them was mount between centres and turn a tenon that fits my chuck. Remounted in the tenon and turned the knob part ie the front with the tailstock gone (like a bowl but instead of hollowing it you leave it the shape of the front of a knob). Then I left a stalk to the chuck side longer than needed and then dismounted and cut it to length on the bandsaw. No one will see the back so who cares its not finished to the front standard. I then marked it for centre and held it in a drill vice while I pilot holed it into which I bunged a small amount of epoxy after which I inserted one of those wood screw on one end and different on the other. They are usually machine screws on one end and wood screws on the other but you can also buy wood screws on both ends. End 1 went into my epoxy'd hole. End 2, now sticking out of the back of the knob goes in another pilot hole in the door. Job done, no bolts, it screwed in really tight and flush and has shown absolutely no sign of any movement.

 

[custard]

Thanks Bob, that makes perfect sense.

 

[tekno.mage]

Most doorknobs are turned as in spindle turning because it is easier to do. The problem is the screws then tend to cut the end grain and fall out.

I don't think that's true. Go to any branch of B&Q or Homebase, look on eBay, or visit any supplier of kitchen cabinets. All the wooden knobs are cross-grain.

Not always the case - I've seen plenty both for sale (including some really expensive "custom" ones online) and fitted to pieces of furniture that were long grain and of course, the screws pull out :-( I've also seen long grain ones offered for sale with a nutsert fitted - which would work well. With some woods the end grain is rather attractive and this may be why some knobs are made this way - and on quality furniture they are dowelled and glued, rather than screwed. With cheap knobs, it's probably because they are faster to make that way round!

I make my own cupboard knobs cross grain, using a home made screw chuck.

 

[andygc]

Not always the case - I've seen plenty both for sale (including some really expensive "custom" ones online) and fitted to pieces of furniture that were long grain and of course, the screws pull out :-

Fair enough, I should have said "most". That includes the thousands of cheap mass-produced ones from B&Q and the like, so I suggest long grain ones are the result of a deliberate design choice, not because they are faster to make.