end grain

[Guest]

Here's another one looking for advice. When turning a bowl I find that the end grain part is rough. What causes this? and how can I correct the problem. I have tried a variety of chisels all with the same result. I can't even sand the roughness out. Any help will be welcome.

 

[Taffy Turner]

This is a perennial problem with turning bowls. It is due to the fact that end grain doesn't cut as well / cleanly as side grain.

The way I deal with this is to take a very light shearing cut with a freshly sharpened gouge as the last cut. If that doesn't work, then I shear scrape with a freshly sharpened scraper.

On some woods even this doesn't work very well, and some heavy sanding is required, starting at the coarse end of the grit grades and working up to finish with 400 grit.

Don't despair - it does get better with practice. Some of my early bowls were very rough on the end grain, but my last couple have been pretty good, and have required much less sanding.

Keep practicing!

 

[Guest]

Thanks Taffy. No easy fix then, just have to practice. Guess we'll have a few rough bowls until I get the hang of it. You mention a scraper, any reccomendations for a begginer?

 

[blurk99]

Hi Jaymar.
I've had this sort of problem with some Pau Amarello (?sp) have you tried sanding out the problem areas with the lathe stopped - it was the only way i could get it looking good, and after applying a finish it doesn't show.

Jim

(ps - sorry if this is an obvious solution and has been already tried)

 

[Cutting Crew]

Hi Jaymar

If you imagine your piece of timber as a bunch of straws tied in circle it may be easier to understand the problem you're having, although not visible to the eye, all the fibres of the timber are hollow .

It's hard to explain but as you try to cut across the ends of the straws (end grain), some part of the straw will be unsupported by its neighbour causing some of the roughness you're getting. If you remember as with cutting coves to always cut downhill, this way the straw is usually supported by the next straw to it, helping to leave a cleaner surface. With a bowl in end grain if you make your final finishing cuts with a freshly sharpened gouge starting from the centre and working outwards towards the rim this should help, as Taffy says it does get better with practice.

I think I'll use one of those straws now and drop it into my beer.

Sorry if it all sounds rubbish but I hope it helps.

Regards....Mike

 

[Taffy Turner]

Jaymar,

My scrapers came from Craft Supplies, but just about all the main tool manufactureres make them.

I have a square and a curved one. When looking for a scraper, make sure you get one that has a thick blade, as thin ones are a waste of time, as they flex under load, and you end up with some very interesting chatter marks!

I would strongly recomend that you get yourself a copy of Keith Rowley's book "Woodturning a Foundation Course" (Try Craft Supplies or Amazon). It covers selection and use of tools (and scrapers) in some details. It also talks about how to get a good finish on end grain.

There is also a companion video to go with the book, which is also very usefull.

Regards
Gary