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Tim Passmore
01-18-2017, 9:55 AM
Advice needed for getting a flat (even/smooth) bottoms when turning platters. Thanks in advance for your insight and expertise.

Michael Mills
01-18-2017, 7:01 PM
I don't know if it will help but I have some soft aluminum bar of various lengths.
A light touch across the surface will leave light marks showing high/low places.
Helps me to see variations normally only seen after applying the finish.

Brian Brown
01-18-2017, 7:16 PM
I'm not really sure why you want a flat bottom. If you are able to get a perfectly flat bottom, there is always a possibility that over time, the wood will absorb humidity, dry more completely, or just plain change shape because it wants to. This will make the turning wobble, or rock. I like to put a foot, or a bead ring on the bottom, so that most of the bottom is recessed up above the ring. Movement in the wood could still cause a change in the ring, but there is a better chance the turning won't be so wobbly. The recessed area also gives you a palette to add some decorative details, and a place to sign your piece. These details make the piece uniquely yours, and prove your attention to detail even on areas that don't usually show.

Tim Passmore
01-18-2017, 7:52 PM
Brian---- I evidentially wasn't clear with my post. I was referring to the inside bottom not the exterior bottom (foot) area.

Michael----- Thanks for the tip.

Barry McFadden
01-18-2017, 9:51 PM
I turn mine with my bowl gouge to the point I would be finished material removal then lightly go over the bottom with a scraper.

brian zawatsky
01-18-2017, 10:19 PM
I use a bowl gouge & as light a cut as I can to get it flat, feel the bottom with the platter spinning for ridges/waves and mark them with a pencil. Then I use a negative rake scraper to remove the ridges and tool marks. You have to sharpen the NRS constantly because the burr wears away quickly, but it does a great job on platter and bowl bottoms.

Thomas Canfield
01-18-2017, 10:36 PM
A ROS (random orbital sander) does wonders to help level a flat inside bottom of platter if the dust bag will allow. I use a bowl gouge prior to sanding.

Brian Brown
01-19-2017, 1:49 AM
What??? You don't leave a Bead/foot on the inside too?!?! :D:D Sorry, didn't think that one out very well.

Justin Stephen
01-19-2017, 9:08 AM
I turn mine with my bowl gouge to the point I would be finished material removal then lightly go over the bottom with a scraper.

Pretty much the same with me except I usually use a negative rake scraper. Doing a light pass with a sanding disc to highlight visually what you should already be feeling with your fingers is also sometimes helpful.

The random orbit sander idea sounds good. I may have to try that someday.

John K Jordan
01-19-2017, 10:14 AM
Advice needed for getting a flat (even/smooth) bottoms when turning platters. Thanks in advance for your insight and expertise.

(Tim, I first thought you wanted the foot flat too! Say what?? :))

I'm an oddball here because I use an unconventional method. Of course I've been asked before how in the heck did I get the inside bottom that perfect. No braggin', ust sayin'.

Note that I consider "flat" can be somewhat different than "even/smooth". If I get sloppy with my tool control and have a depression in the center I make additional "whisper" cuts down the side and across the entire bottom, or just in the center for a hump. For unevenness such as even very slight ripples (and any small "nib" in the exact center) I use a different method.

After my finish cuts I touch up with handled scrapers as needed - these days I like the Thompsons ground with a negative rake; round nose or the Sorby teardrop for tighter curves and closed-in rims on bowls. I then use hand scrapers to remove any remaining small ripples/unevenness. Anything I judge bigger than "small", back to the gouge or conventional scrapers.

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The larger scrapers with very slight curves on the side are the best for platters. I use these sometimes with the lathe turning at a slow speed but often with the lathe off, especially near the center. I almost always scrape with the grain as you would with flatwork. This usually takes only a few minutes.

I can't fix what I can't see or feel. Once I completed and finished a small squarish platter and was horrified by very shallow concentric ripples on the bottom that were revealed when I took it off the lathe and tilted it in my hand. Now I do several things. First, run my fingers over the surface. You can feel ripples and unevenness that you can never see on a non-shiny surface. Second, for most woods I use a cloth to apply a bit of naptha to wet the surface and use a glancing light to inspect the bottom. This will usually show up the shallowest ripples.

Note that if the final finish is not glossy, shallow ripples may be hidden to the eye but you can still feel them. If the final finish is glossy the light will easily reveal any ripples.

One thing I almost always do which makes the scraping easier, more effective, and more relaxing (and gives my feet a break) - I unscrew the chuck from the lathe and sit in a comfortable chair in good light and smooth the bottom as needed. In addition, I often sand this way by hand, while seated, again with the grain. This will eliminate the horrible fine concentric scratches you see in so much face work. BTW, with some woods and situations I often sand with the figure as well as the grain where the figure is different.

One huge advantage of smoothing with a scraper is coarse sandpaper is almost never needed. Power sanding is rarely needed. Ask any fine furniture maker - a scraper can give an incredibly smooth surface. I usually don't need anything coarser than 320 grit. (Omitting the power sanding also eliminates clouds of dust.) BTW, when I do power sand I far prefer the tiny Grex pneumatic sander - it is a random orbital sander with good low speed control for very gentle sanding. I've taken my close-quarters/angled drill out of my turning area.

I find this method very effective. I should do some photos some day showing the before, the process, and the after of ripple removal.

Here are older pics of some things I would hate to do without the scrapers. The hand scrapers are especially useful on the squarish dished platters such as in the second photo. The hand scrapers are especially useful on the interrupted cuts on the wings. The one turned upside down to show the bottom shape (cherry) is the one I almost threw away after it was completely finished. I was able to repair the inside by hand (off the lathe) just in time for a wedding gift.

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Note that hand scrapers must be good quality and properly sharpened.

Sorry for the long response to your 20 word query. I always get carried away. Part of the problem might be typing on a real keyboard instead of an iPad.

JKJ

Wes Ramsey
01-19-2017, 10:34 AM
I use a flat scraper both inside and out. Inside I use it to flatten the bottom. Outside I use it to do final shaping. Funny how a flat scraper can coax the perfect curve.

Tim Passmore
01-19-2017, 5:25 PM
Barry, Brian, Thomas, Justin, John, and Wes----Thanks guys for taking the time to provide insight. I have a feeling, that no matter the technique, practice and patience are the keys to success-----like most things in life. I love the practice part��.

John K Jordan
01-19-2017, 6:34 PM
I love the practice part.

If you don't do so now, you might try what I and some others I know often do when turning: Make each cut a practice cut.

After roughing a cylinder for a spindle, box, etc, rather than just quickly hog down to the target diameter/taper I like to make practice cuts with the skew for the smoothest possible cylinder. Try different techniques and different tools. Cut some beads and coves and grooves, cut them away. Try different stances and tool presentations and see what works with that particular chunk of wood. For example, doing this on a thin spindle in osage orange I discovered early at least THAT piece of wood was real "chippy" with a certain low-angle skew so I had plenty of time to experiment with different grinds and presentations before it got too thing.

When getting closer to the target shape, I start making each cut a finish cut, long curves and tapers as smooth as possible, sneaking up on the shape. By the time I do six finish cuts in a row the last one is a keeper!

Same thing for face work. When truing the top face of a bowl I might try to get it as flat as possible with various gouge grinds. Halfway through shaping the side I try different things and learn what is best for that chunk. Sometimes I play with shapes and stumble into something I like better than what I intended!

It is actually a quite relaxing way to turn!

The disadvantage of this method is it takes longer, may not be for the production wannabe or the type-A goal oriented. The advantages are obvious.

JKJ

jared herbert
01-19-2017, 9:42 PM
So a question about the plates in the second picture. What are the approximate dimensions? Did you turn a round plate and then cut the sides off with a bandsaw to make the rectangular shape? Just wondering. I like the looks of them. thanks

John Beaver
01-19-2017, 10:52 PM
A nice little trick is to take a stick of hot melt glue and lay it on the piece. It does a great job of showing bumps and divots. Then use a light scraper to fix those areas.

John K Jordan
01-19-2017, 10:53 PM
So a question about the plates in the second picture. What are the approximate dimensions? Did you turn a round plate and then cut the sides off with a bandsaw to make the rectangular shape? Just wondering. I like the looks of them. thanks

Thank you! These are about 9" across, a good size for a table, shelf or counter. I've made some 18-19" platters and frankly, we don't use them too often since they are so big. Besides, these are quicker to turn than a big platter.

I made one and liked the design and the way the foot raised it off the table (and my Lovely Bride likes it!) so I made more - mostly for wedding presents or to give to friends. This one from figured maple I gave to a friend in Italy who hosted us and gave us the insider tour of northern Italy. (and I gave the one made from walnut burl for her mother who taught us some genuine northern Italian cooking!)

I've posted this before but here it is again...

http://www.sawmillcreek.org/attachment.php?attachmentid=335857&d=1460864122

I've used a variety of woods, eastern red cedar, maple, cherry, basswood (for chip carving), walnut burl. I plan to do one soon from olive and some from sapele, canary wood, dogwood, and more cherry and cedar.

I cut to outer shape before turning for several reasons. One, I can use a narrower board - I can use a 10" wide board for this size. Cutting to a line drawn on a flat surface is easier than trying to cut after it is turned. Also, if cut after turning there is a chance of chipping the rim. And importantly, if I can see the rim I can more easily shape the inside to match the outside and give a more pleasing uniform thickness at the rim. If I turned round then cut the outline it would be easy to get this "wrong", too thick or thin in the middle of a side. (unless that's the intent!) Getting the rim uniform is easier with a shallower dish shape.

I generally start with a 2" thick dry wood, draw the outside shape using a template I made, then cut the outline with the bandsaw, smoothing a bit with a disk sander. I drill a hole in the top for a screw chuck, turn a recess in the base for a chuck and turn and scrape/sand as needed. (I add enough detail to the bottom of the foot to distract the eye from the fact I'm leaving the recess there - it looks like it's part of the design.)

After the bottom is done I turn it around and mount it in a chuck and do the top side.

Since I'm cutting air towards the outside the scrapers really come in handy on the wings. They clean up the inevitable ripples so well I can usually start with 400 grit or occasionally 350, sanding mostly off the lathe, with the grain. I use 2" wide sanding sticks to soften the rim before I take it off the lathe. BTW, if anyone has not made some of these, they are incredibly handy at the lathe.

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Also, when sanding the flatter surfaces on things like this I found the perfect sanding block - a white Magic Rub eraser! Perfect size for me to grip and flexible for gentle curves.

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I finish with sanding sealer, oil, beeswax for the cedar, and sometimes TruOil.

BTW, this design was inspired by good friend Frank Penta's squarish plates with with laminated strips. However, he makes his from 4/4 which sat low on the table (like a real plate should!) and usually a little flatter on the sides: http://www.frankpenta.com/index.php/gallery/category/36-eight-inch-plates When I showed some to him this design got the Penta a-Proval! Frank is a wonderful person, turner, and teacher. He has lots how-to documents on his web site, some by some of his "guys." http://www.frankpenta.com/index.php/projects

That was probably more than you wanted to know but I get carried away easily! (and someone might be interested)

JKJ

Justin Stephen
01-19-2017, 11:04 PM
BTW, this design was inspired by good friend Frank Penta's squarish plates with with laminated strips. However, he makes his from 4/4 which sat low on the table (like a real plate should!) and usually a little flatter on the sides: http://www.frankpenta.com/index.php/gallery/category/36-eight-inch-plates When I showed some to him this design got the Penta a-Proval! Frank is a wonderful person, turner, and teacher. He has lots how-to documents on his web site, some by some of his "guys." http://www.frankpenta.com/index.php/projects


I went to Frank's talk at the Virginia Symposium this year. As impressive as his laminations are (and they are indeed), I was just as marveled by some of the nice shapes of his platters.

Tim Passmore
01-20-2017, 6:42 AM
Fabulous work John! Thanks for the tips.

Dean S Walker
01-20-2017, 9:03 AM
Excellent work John those are gorgeous. I 2nd the hand scrapers, I also use files a lot to finish the very tips of handles/spindles. I know this is a bowl question but I have found that anything you can cut rather than sand generally turns out better.

Leo Van Der Loo
01-20-2017, 10:02 PM
Like Brian Zawatsky, when I get close to the final cut I take a wide scraper that has a very slight curve on the cutting edge, so not straight, I then take a very thin shaving with my hand sliding along the toolrest, feel and do it again.

Then with the lathe spinning I feel where the higher and lower areas are and just touch the edges with a pencil of the higher area while the lathe is still spinning, taking a light cut and again feel, that slight curve on the end of your scraper can clean and flatten a platter.

Though a platter with a slight curved inside is easier to make than an exact flat surface ;).

This is a 12” Oregon Myrtle platter/tray I made, and yes it is flat smooth and beautiful :D.

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