Parting and cleaning up the parted workpiece...

[Jon Rista]

This image below comes from a post from @John K Jordan in another thread. However, it reminded me I keep meaning to ask this question about parting, and cleaning up the nub or remaining unwanted wood on the parted workpiece.

View attachment 81073

I've been turning, on and off, since 2020. I have a decent amount of skill, but I'm in that phase, and have been for a bit here, where I'm never really satisfied with my work. I've gone through rounds with sanding techniques, tooling techniques, grinding techniques. I have good skill, but, also never quite satisfied and always trying to improve. Currently, I think my single greatest struggle, is getting good, clean results on my workpieces, after parting. I have a lot of trouble with this.

FWIW, this is mostly on smaller items, like those pictured in John's photo above. This really is not an issue with bowls or platters, its spindle type pieces mostly, although I sometimes have issues parting vases as well (mostly, tearout on the bottom...which seems to occur as a result of the parting process with parting tools, even when they are as sharp as I can make them.

When I first started, I used parting tools, left a bit of wood on, sanded that down. But it never looked good. So I started parting part way, then sawing through the connecting piece of wood, which also left a piece of wood, but I was able to make it smaller. I still couldn't get really great results, and there were often shape issues, and with certain woods sanding that wood down can take ages. I tried "carving" that wood off for a while, and that seemed to lead to worse shape issues. I then tried to actually turn the piece right off, shaping optimally as I went, and 90% of the time the piece would break off, shredding fibers right into the piece, which then of course was unfixable. So I went back to parting tools and sawing the last little bit to leave a little nub of wood, and I'm still trying to figure out the best way to deal with that.

Recently, after parting and sawing off the workpiece, I have taken to using a rasp, to remove the nub, and try and lightly shape. I then sand, and its hit or miss, whether I can actually get a nice, clean, quality surface around the parting point that looks seamless with the rest of the piece. However, using the rasp, has improved things, it gives me more control than trying to sand off the remaining wood nub with a sanding disc, and I'm able to keep a better shape overall most of the time. The thing that is really challenging for me, is getting the final finish around the parted area to look as nice as the rest of the workpiece.

A secondary issue I have with parting, and this mostly happens with vases where I may be parting through a larger area of wood (the base of my vases are usually around 2" in diameter across most of the time, or larger), is tearout in the fibers on the bottom of the piece. Even when I sharpen the parting tool as much as I possibly can, it still seems like most woods that I turn, end up tearing out. I've tried varying my speed, going very slowly...which does minimize the issue, but it does not seem to eliminate it. I don't know if I've turned a vase yet where I really like the base...they all seem to look terrible.

So anyway. Curious how everyone else parts their workpieces. What the tricks are to produce a clean, high quality result in the parted areas, and avoid serious problems like tearout (which can essentially be unfixable, since it can extend so far into the wood.)

 

[Thomas Wentzel]

Thanks for posting this issue, Jon, as a new-ish turner I have a similar problem. I'll be watching for advice.
Tom

 

[John K Jordan]

"Curious how everyone else parts their workpieces."

IN GENERAL
I part off spindles and smallish things almost, but not all the way, then use a fine saw to cut the rest of the way. This prevents the last little bit of wood breaking and possibly pulling fibers out of the bottom of the piece. These can be a horror to fix unless the turner is not too picky or has bad eyesight.

Before parting, I have usually already cut away the supporting block for clearance then shaped the and detailed the bottom with spindle gouge, skew, or special tools. What's left then, is just a tiny nub which I pare away with a rotating/slicing cut with a spindle gouge, skew, scalpel, or other tool depending - some are custom tools. I don't touch the turned part.

If I use a parting tool to prepare to remove the waste, I part well away from the intended bottom, remove much of the supporting waste wood to provide the aforementioned clearance which gives me room to make clean facing cuts with the skew or curved cuts with the spindle gouge, perhaps using special NRS and other custom tools, perhaps shear scraping with the side of a spindle gouge.

Then, again, depending, I may smooth the bottom with a small curved hand scraper before smoothing with sandpaper.
If needed, I devise a method to reverse mount the piece and turn, smooth, sand, and detail the bottom of the foot.

There are numerous ways to reverse either face or spindle work. Some involve jam chucking, double-sided tape, cole or other jaws, sometimes larger jaws tightened on a cylinder of closed-cell foam shaped to hold the piece. I often support larger pieces with multiple strips of tape, my favorite is Scotch 2060.

Here's an example of finishing up the bottom of an African Blackwood box, parted off, reversed and loosely jammed into a turned piece of scrap wood, then firmly secured with multiple pieces of the green Scotch 2030 masking tape (this is NOT your low-rent green masking tape found at HD, etc which is worthless for this - the 2060 is made for "hard to stick" surfaces such as concrete, cinderblock, wood, etc., holds FAR better). With the piece secured so I couldn't MAKE it wobble, I had easy access to the bottom to shape, refine, smooth, and finish as I liked. I clean up MANY pieces this way, often held in different ways depending on the shape. I'll even use Cole Jaws at times, but not often, but if I do the piece is secured with the same green 2060 tape. I do not like pieces coming off the lathe uninvited.



BOWLS, SMALL PLATTERS
On most bowls and platters I avoid all the fuss of reverse mounting by simply turning the entire bottom first while holding the flat top in a Glaser screw chuck.

Turning the bottom includes defining the foot, shaping inside the foot, cutting a shallow recess for the chuck, and detailing inside the foot and the recess. Turn the entire outside, smooth with NRS, remove from lathe (still in the screw chuck) and hold with a carving/finishing stand to hand scrape and hand sand the bottom, then apply finish. Turn the piece over and hold by the recess then do the top. This avoids any/all parting off.

This is a "winged" piece made this way, the first pic showing the foot/recess/detail done and me turning the winged outside. The second photo is a similar one all done. As mentioned, zero reversing and cleanup needed with this method - by the time the start on the top of the platter/inside of the bowl, the bottom is done. (Note: I turn dry wood.)



SPINDLES
For spindles as in the earlier picture, I shape the end, ALMOST part off and saw off the same way, then use a sharp skew to remove the nub. No tearout or pulled fibers allowed or experienced. Then I and sand the end to achieve the profile - sometimes starting with sanding sticks I make, sometimes hand sanding, and often finishing up by placing a piece of sand paper on a hard surface covered with carpet and sand while rotating. My lathes have flat topped headstocks so I inset or stick the carpet there. Handy. Finish was applied to the entire piece before this point, so I just need to put finish on the end. I do all wands, gavels and some other handles, finger tops, and more.

If the piece is a two part piece with a hole, such as some handles, little weed pots, etc, I'll turn a "dowel" from soft wood to jam into the hole to hold it securely and turn the end. Sometimes if the piece is long I'll lightly support it with my left hand while turning, smoothing, detailing, and finishing the end.

That's how I clean up the end of many spindles, conductor's batons, rider's crops, and handles like this:



Sorry, can't find any good photos of details on this specific subject. If I had the energy I'd do a video of every method I use.
For those who read, a good book to have on the shelf is "Fixtures and Chucks for Woodturning" by Doc Green.
Another is "A Guide to Work-Holding on the Lathe" by Fred Holder
My shop library would be incomplete without these two books (and a dozens of others). Youtube might be helpful for those who don't read.

POWER SANDNG
I never, ever, use any type of power tool such as a sanding disk to finish the end of any turning, bowl/platter or spindle - not needed and too much chance of destroying the carefully shaped end.

Many years ago I took a bowl-turning course. What a waste of time - I learned many bad techniques. One was to part the waste wood or waste block then use a sanding disk to clean up and make a depression in the bottom of the foot so the piece would sit on the table. Never again.

All these are things I teach. I'm sure others have different methods. I'm also sure there are many details of my methods I forgot or got too lazy to write. Come visit. I will gladly show all methods. No secrets. My fee is a good story or a good joke.

JKJ

 

[Dave Jones]

Glue a felt pad on the bottom?

Ok, a bit more serious. I just sand the best I can while it's on the lathe. when it comes off, I chisel the nub, and sand some more. A little sanding sealer (shellac is my very best friend) and a little more sanding. I do often have to start at a very low grit on the bottom, but once that is satisfactory, it's a quick progression up to 3 or 400, or wherever I'm stopping on that particular piece.

If I'm ever worried that the bottom won't be flat anymore (pretty uncommon) I tape a sheet of sandpaper to a granite tile I keep about (it cost a dollar at the habitat store) and scoot the bottom of the piece around on it until I feel better.

I also like to leave a chiseled recess sometimes. If the wood is good enough (I turn a lot of questionable wood) I'll grab a curved chisel and make a flower or swirl in the bottom. Just be careful, the first couple I did like that, my wife made fun of it, said it looked like a b-hole.

 

[Jon Rista]

Glue a felt pad on the bottom?

Ok, a bit more serious. I just sand the best I can while it's on the lathe. when it comes off, I chisel the nub, and sand some more. A little sanding sealer (shellac is my very best friend) and a little more sanding. I do often have to start at a very low grit on the bottom, but once that is satisfactory, it's a quick progression up to 3 or 400, or wherever I'm stopping on that particular piece.

If I'm ever worried that the bottom won't be flat anymore (pretty uncommon) I tape a sheet of sandpaper to a granite tile I keep about (it cost a dollar at the habitat store) and scoot the bottom of the piece around on it until I feel better.

I also like to leave a chiseled recess sometimes. If the wood is good enough (I turn a lot of questionable wood) I'll grab a curved chisel and make a flower or swirl in the bottom. Just be careful, the first couple I did like that, my wife made fun of it, said it looked like a b-hole.

I like the idea of decorating the parting point... Maybe its just what I've been turning lately, but I always seem to have trouble getting sandpaper into that area, after I've turned down the connection to the chucked block, before finally parting it off. So sanding things to be really nice and clean, ends up being a ton of work, and if I accidentally tear out the fibers when I part (less common now that I'm using a saw to fully part), then that becomes a nearly uncorrectable issue. Except, if I were to carve it out.

Shaping is one of my bigger concerns, too. I've been turning wooden eggs, and that has been a consistent struggle for me. The top of the eggs (which is where I'm parting...was parting at the bottom of the eggs, but I again was having a hard time getting enough room to sand well in there, without at least, wasting a lot of good blank from which I could turn another egg or two. So I flipped, and turned the top towards the parting end. The tops of these eggs, once parted and sanded to the point where they look good, often end up misshaped. I've spent even more time, re-shaping with sandpaper...which is a dubious process at best! Since this shaping issue is always at the tip of the egg, there isn't any good way to re-mount it so I can clean up the shaping issues on the lathe (at least, not that I know of....perhaps a vacuum chuck might assist there, I don't own one right now.) I have similar issues with other kinds of items I turn, though...keeping the shape at the parted off point nice.

 

[Webb Willmott]

Why not turn an egg shaped cup for a jam chuck and cut splits on the bandsaw. Then use a hose clamp to compress it on the egg. Use the tail stock to line it up so it runs true then you can turn the end off and lightly sand?

 

[Jon Rista]

Why not turn an egg shaped cup for a jam chuck and cut splits on the bandsaw. Then use a hose clamp to compress it on the egg. Use the tail stock to line it up so it runs true then you can turn the end off and lightly sand?

"and cut splits on the bandsaw." Not sure I understand this part?

 

[Webb Willmott]

Since it’s a spindle, cut with the grain so you have “fingers”. Imagine turning a box and sticking the egg in the end. You’re sticking the egg in a tube that the clamp will pull the sides down on the egg.

 

[Dave Landers]

"and cut splits on the bandsaw." Not sure I understand this part?

Something like this https://www.aawforum.org/community/threads/hose-clamp-chuck-for-round-objects.17068/post-172825

 

[Webb Willmott]

Thank you Dave. A picture is worth a thousand words.

 

[John K Jordan]

Shaping is one of my bigger concerns, too. I've been turning wooden eggs, and that has been a consistent struggle for me. The top of the eggs (which is where I'm parting...was parting at the bottom of the eggs, but I again was having a hard time getting enough room to sand well in there

I made this just to hold chicken-sized eggs. I used somewhat fingers flexible ERC, shaped the inside to hold the egg, tighten with a hose clamp (watch the fingers). Since ERC is not an especially strong wood I made a threaded dogwood insert to mount on the lathe:



Having chickens I'm sensitive to what a real egg looks like I've see some turned eggs that just don't look right to me.. Although there are a lot of natural variations, I picked a typical egg shape and size that made me happy. I made a template to work from by mounting a point source LED light on the shop ceiling and carefully tracing the shadow. Measuring key points and sizing with a parting tool and calipers gives me the egg shape I want.

I've also made some wooden guinea and peacock eggs, smaller and larger than chicken and sometimes shaped differently. I oftenuse these as "decoy" eggs to entice a bird to lay eggs in a particular spot.

FWIW, a turned chicken egg next to a turned peafowl egg.


(Remember: if a picture is worth a 1000 words, a word must be worth a milli-picture.)

JKJ