wood screws & knobs

[mrgrimsdale]

Any advice on suitable device for cutting wood screws? 5/8" o.d.



And advice on turning sequence for knobs like these? Knobs first and threaded holes after, or other way around? Say I want to do a run of twenty? One by one from a long blank?
Are knobs always turned with grain lengthways? The ones I've looked at all are i.e. end grain on the face. It would make sense as otherwise there would be weak grain at the narrow bit.

PS found the answer to grain - 'end grain' knobs are the norm

[jaco]

First the knobs, end grain.

I saw a wood screw kit the other day, but the size was 1"
Did not buy as I was not sure what to do with 1" wooden screws

[mrgrimsdale]

Found screw kit: axminster.
Sorted sequence:
turn a square length with a measured flat to fit a chuck, for each knob
separate
mount in a chuck and turn base and part shape
drill hole and tap
remount on threaded dowel in a chuck, and finish off
similar operation in reverse for the 'bolts'

I want to do this as it seems to be the best way to attach a knob. Next best would be similar but with a plain dowel glued and wedged, instead of the tapped hole and wooden 'bolt'

[colincott]

Hi Jacob

I will tell you that those ones are not so good in end grain as they tend to tire the grain out as they cut.

You want to try and get one of the old ones ( I will post some pics of what I mean ), I have both types and the older ones are much better but they do tend to get good prices on ebay.

[engineerone]

it's a long time since i did wood turning, but frankly i would use my old metal working trick.

1. produce a length of threaded rod which has a hole in the rear to allow for the centre to enter.
2. drill and tap the blocks on the pillar drill. and maybe a backwards thread.
3. screw onto threaded rod, and turn the handle.

gripping the handles whilst drilling and tapping is fraught with dangers of slippage and marking the surfaces.

paul

[mrgrimsdale]

I've given up on the threaded knob + wood bolt mainly because I've now looked at a lot of them and I think they were specialist machine made - they are all very uniform and perfect without those little hand made variations you'd expect. But they certainly seem to be the best way of keeping a knob firmly fixed.
So it's back to the knob + shaft in one, wedged. Much simpler with fewer operations; turn blank to fit a chuck, turn knob and shaft all in one, separate.
Should I be able to get a perfect finish with skew chisels on something with tight curves like a knob, or perhaps just on the easy curves, or is extended use of sandpaper approved?

[cove]

The perfect turner might get a perfect finish. You should be able to get a pretty good finish on these straight off the skew and spindle gouge but usually fine sanding will help. Don't worry about it.

[mrgrimsdale]

Jan 2, 2009 21:09:28 GMT cove said:

The perfect turner might get a perfect finish. You should be able to get a pretty good finish on these straight off the skew and spindle gouge but usually fine sanding will help. Don't worry about it.

Cheers ta.
I'm not worried I'm just aiming at speed; fast and efficient to a reasonable standard.
I've been looking at Percy W Blandford's "Wood Turning" 1953. A little Foyles handbook. Packed with useful info, excellent book.
Amazed at old Percy's productivity!
He has been at it since at least 1953 but has new titles too. Is he real or just a brand name for a team, perhaps?

[cove]

That's the pragmatic approach. dedicated enthusiasts spend time going for the perfect finish off the tool but you have to be good to avoid transition marks or uneven places that benefit from sanding. It is quite easy to get a perfect finish but not so easy to get it all over the piece and have it the right shape at the same time! It is normally quicker to think of the sandpaper as a finishing tool.

I saw Richard Raffan make a bowl once and he got a lovely smooth surface inside and out with no sanding. But he did say the wood had a lot to do with it. And it all went wrong when he turned through the bottom.