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bassmansimon
5th December 2012, 04:20 PM
hi everyone,

having done a few bowls in blackwood, jarrah, red cedar, sassafras and camphor, nearly all of these have ended up with dodgy looking sections where there is end-grain.

It looks like dodgy sanding, but i had done my absolute best sanding through the grits (100, 150, 240, 320) then EEE and Shellawax Cream.

am i missing a step? do people use sanding sealer or something else between turning on the tools and then sanding/polishing? if so, at what stage should it be applied?

My lathe only goes in one direction (no reverse gear), so i'm sure that isn't helping also.

Thanks, Simon.

RETIRED
5th December 2012, 05:09 PM
Without seeing them I would say you have tear out and unfortunately no amount (well actually, a real lot) of sanding will fix it.

wheelinround
5th December 2012, 05:53 PM
As has said

Simon I keep a spray bottle of water handy and wet and dry or anti-clog paper and sand away end grain fur it takes time but often worth going that extra mile for. Power sanding can also make it easier.

bassmansimon
5th December 2012, 06:36 PM
I'm adding two photos of the same figured Blackwood bowl. One shows beautiful side grain with great figure. The other shows the endgrain of the same project.

wheelinround
5th December 2012, 07:02 PM
WOW 2nd photo almost one would think its a piece of different wood.

Simon when I first started turning I had the same problem and was advised as above and it works for me.

It just takes time I do use also a sanding sealer Organoil brand or Shellac and sand.

Sometimes I even leave it at a certain stage to add to the look as it is wood and it does have grain a natural look and feel.

RETIRED
5th December 2012, 07:04 PM
Tear out. Sharp chisel and a deft touch needed.

Quite often Blackwood can be a right um mongrel and you have to use a scraper for the final cuts.

bassmansimon
5th December 2012, 07:23 PM
thanks to you both. I haven't purchased a new scraper yet. I just had a starter pack of chisels, and a professional turner said that my scraper was better suited to be changed into a skew chisel, which is what he did for me.

I know if I am to get better at face turning, I need a scraper. Any advice for an all-round size/shape scraper, or is it truly important to get a few? I only have the one bowl gouge, two skews, one parting tool, one detail gouge and one roughing gouge.

When i visit my father's place, i will give the tools a good sharpening.

With the sanding sealer, at what point do you apply it? Is it before any sanding at all, or after rough sanding (100ish) but before smooth (240ish)?

tea lady
5th December 2012, 07:52 PM
Could try also a bit of hand sanding in the reverse grain areas. Just stop the lathe and sand just that area by hand in the reverse direction. Should only need to do it with the lowest grit. :shrug: Doesn't look too bad as far at tear out goes.

You could also try "sheer scraping" but you really need to have someone show you how. A bit hard to do it just by looking at pics. There is a thread on here somewhere.:cool:

powderpost
5th December 2012, 09:19 PM
Short answer to the problem, you are using blunt tools.
Jim

ian thorn
5th December 2012, 09:46 PM
I think before you buy the scraper you should get a grinder and a diamond hone this would help no end( or you could steal your dads ) I would sand with 80 grit usinng the spray mist to get rid of most of the tearout then aply sanding sealer let it dry over night then start again going through the grades

regards Ian

bassmansimon
5th December 2012, 09:52 PM
Thanks for the feedback. I went halves with my dad on the lathe, and we got an 8 inch grinder and pink wheel for sharpening the turning tools but for stupid reasons I have the lathe but he has the grinder at the moment haha.

Good to know this problem is solvable with sharpened tools, a scraper, some sanding sealer, and hand sanding in opposite direction, while using a spray bottle.
I think I've got all the comments and tips covered there. Thanks everyone these forums and people like you are a fantastic help :2tsup:

Simon

RETIRED
5th December 2012, 10:36 PM
Short answer to the problem, you are using blunt tools.
Jim


I think before you buy the scraper you should get a grinder and a diamond hone this would help no end( or you could steal your dads ) I would sand with 80 grit usinng the spray mist to get rid of most of the tearout then aply sanding sealer let it dry over night then start again going through the grades

regards IanI was being polite, unusual, I know.:wink:

Drillit
6th December 2012, 09:52 AM
I would just add a couple of things if I could. Firstly sanding itself can cause this type of problem, particularly if you are sanding on a relevantly high speed.
It should be a low speed. I have found that some woods do tend to tear more than others. If you get your scraper up really high in the trailing position and take fine cuts it may help
with the finish, others use a negative rake scraper. I also find that when I go thru the grades and finish with say 320, I then wet the piece down with water on a piece of paper towel, let dry and
sand down with 400. I find that process works well, but I dont seal before I use EEE and Shellawax, because I think the results are better without doing that. Having said that (as others have said), sharp tools
are imperative. Drillit.

Bruce White
6th December 2012, 10:46 AM
Tear out. Sharp chisel and a deft touch needed.

Quite often Blackwood can be a right um mongrel and you have to use a scraper for the final cuts.

I pretty much only use a scraper and sometimes a skew from start to finish on my bowls now. Find I get a far better finish off the tool. Hardly ever use a gouge on them.

RETIRED
6th December 2012, 11:00 AM
I pretty much only use a scraper and sometimes a skew from start to finish on my bowls now. Find I get a far better finish off the tool. Hardly ever use a gouge on them.As a scraper I hope.:D

rsser
6th December 2012, 11:15 AM
Some lumps of Blackwood come across as brittle to me just as a by-the-way.

Another thing you can try to avoid tear-out is using a small bowl gouge with light cuts to finish with.

Bruce White
6th December 2012, 11:26 AM
As a scraper I hope.:D

Yep

turnerted
6th December 2012, 04:43 PM
Try gently power sanding on the affected spots with the lathe stationary then sand again with the same grit with the lathe rotating.
Ted