Techniques for Flattening Bowl Blanks?

[Ben Martin]

What do you guys use to flatten the bottom bowl of bowl blanks for easier/safer mounting on the lathe? I was thinking about picking up a power planer for this purpose, but wanted to hear what you guys do first. I have been having some issues with the chainsaw marks both on the lathe and also at the bandsaw.

Thanks!

[Brian Libby]

I would turn between centers then mount in a chuck.

[David E Keller]

I typically do it between centers on the lathe... Flat enough is good enough for me generally. Jerry Mercantel makes a really nifty drive chuck that helps with uneven pieces.

[Paul Gallian]

from the chainsaw (cutting out the pith) then to the Bandsaw cutting to a circle blank - then faceplate on the chainsawed surface - other side using a live center, turn a tenon - then to chuck - then you can flatten all you want.

[Paul Gallian]

I really like the Woodworm screw with the Supernova2 chuck -- no need to have it very flat...

[Jamie Donaldson]

Chainsaw blanks to yield a first flat surface, then rough turn between centers after knocking off any bark that would be at a mounting point, like at the tailstock end. I use several tools when needed- a meat cleaver or hatchet for bark removal, electric chainsaw for rough cutting in the shop, bandsaw, whatever is needed to get the blank ready to be mounted between centers for further shaping.

[Baxter Smith]

I use a small handplane to flatten just the area for a faceplate if I didn't get that spot smooth with the chainsaw. 95% of the time I mount between centers but once the blank gets over 15 or 16" in diameter, I find the faceplate easier and safer if you also use the tailstock when first roughing to shape. Especially if I am going to use a recess to later hold with. It does require that you have split the blank carefully with the chainsaw because your opportunity for reorienting the blank is gone using the faceplate.

[Michael Menzli]

I do the chainsaw then bandsaw route. I then drill with a forstner bit to mount on my nova g3. I dont care for this method but the quickest for me to date. Still trying to find the best orientation of things to get the best figure and yields.

[Ben Martin]

So I am assuming that turning between centers is only a safe option on smaller blanks (>12")? I have some 18-20" blanks waiting to be turned, is a face plate the preferred method for these? One way I have done this in the past was use a forstner bit to create a level surface for the face plate to mount to. I also like the screw that came with my Stronghold, I am just concerned that I need a pretty flat surface, perhaps this isn't right...

I was watching an episode of American Woodshop where he used a power planer, that is what perked my interest. BUT, a lot of things he does on that show don't seem too kosher with me...

[Scott Hackler]

Smaller blanks (under 8") = between centers, tail stock end trued up and tenon cut for reversing in the chuck.

Larger blanks (8"+) = screw a face plate to one side, bring up tail stock for the same treatment

Every once in a while I have to work on the face plate side a bit with either the chainsaw or a hand chisel to have a flat spot for mounting.

[David E Keller]

I like a screw chuck for larger blanks, and I mount it in a chuck with the largest jaws I have and use the tail stock the entire time I turn the outside and the tenon... For bowls that size, I'll use the largest jaws for holding the blank anyway, so there's no extra step. Even I the top is a little rough, I feel pretty secure with the screw and tail stock... YMMV!

[Mark Levitski]

Ben,

Turn between centers. Use a large morse taper drive w/ two spurs (I also use the Oneway Big Bite in one of my chucks). Don't need a flat surface, but get the bark off where the drive sits. Rough turn the piece and move it around a bit to get what you want from the wood. Eventually settle on something and turn the tenon or recess for the chuck. Pop off the headstock drive and reverse the piece into a chuck. Doesn't take very long, and you can turn large blanks this way using some common sense. Shoot, you don't need anything too complicated. KISS.

Mark

[charlie knighton]

i turn mostly endgrain, so chainsaw and then between centers, occasionally i need that flat spot and so out of round that i take up my lancelot with both hands, the blank must be secured in some fashion

[Bernie Weishapl]

I mount blanks up to 20" using a face plate. Once I have the outside shaped and a tenon turned I mount it in a chuck.

[dan carter]

Here is Jerry's screw faceplate being used on a 11 1/2 dia piece of cedar. It worked well. Used a band saw to cut the limb off to make it reasonably flat. Using this type of device, it isn't all that critical for the wood to be flat.

[Thomas Canfield]

I use a 2 3/4" Forstner bit to form a flat spot on rough pieces to either mount using the worm screw in a chuck or a 2 1/2" Don Pencil face plate on the flat surface. That works for bark surface, rough chainsaw cut, or partial void. I do use the tail stock and live center and then turn a tenon on the bottom for a chuck. That has worked on pieces up to 100# and 19 7/8" diameter on my Powermatic. The Forstner bit allows me to level up the rough piece before facing to get the orientation I want, and do have a bulls-eye level to check my face when I use my 1/2" corded drill by hand or piece on the drill press (up to 16" D).

[curtis rosche]

i cut a flat spot with the chainsaw and then drill a inch hole for the chuck.

[Mike Cruz]

Ben, if I understand your question correctly, you are having trouble mounting a faceplate on surfaces that have been cut with your chainsaw, right? If so, I think the first thing you need to do is make cleaner cuts. I don't think there is anything inherent in a chainsaw cut that is too rough to mount a faceplate. So, you might want to either take more care in your cuts, or maybe a beefier chainsaw might be in order. Not sure what you are cutting with, but an underpowered "homeowner" chainsaw will not make as smooth of a cut as a heavy (heavier) duty saw.

Now, if you are only talking about those instances that "happen" to be bad cuts (but you don't normally have those) and want to know what to do with an occasional slab like that, there are many options...most of which have already been suggested. Turning between centers is probably the simplest. But your idea of a power planer to take off the high spots will work.

[Jeremy Leasure]

The last few logs I've chainsawed I've taken a block plane to, just because. I haven't had any issues, but I figured, "why not?".

[Mike Cruz]

I never ask, "Why not?" Why? Because I found out a couple of times! ;)

[Jim Sebring]

I flatten blanks up to 8 inches wide on my Grizzley jointer. I occasionally use my Harbor Freight power planer to get a flat enough spot to attach a face plate. If it's a big piece, I use a driver similiar to the one Dan mentioned above. That one will drive the Gates of Hades, I do declare! I do not like spur drives - on green wood they just bore a hole in the blank.

[Reed Gray]

Well, I cheat. I have a Laguna 16HD bandsaw, 4.5 hp motor and cuts 16 inches high. A lot can be done with the chainsaw. It really helps to mark both ends of a lot before cutting. I wedge the log so it won't roll. I mark a plumb line with a level on both ends. I then use plywood strips from 1 to 8 inches to lay out parallel lines and leave 1/2 inch for the saw kerf. Having the lines makes it easier to get a smooth cut. I also find I get a smoother cut with a sharp chain. Also, if I rock back and forth, it gets more bumpy than if I pivot the nose down as far as I can on the back side, then cut down the front side, following the line.

For a flat spot on top, a Forstner bit and your depth stop on your drill press will do a fast and easy flat spot. If it isn't too bad of a surface, you can get away with a little (1/8 inch max) gap/rocking, but do turn slower till you can reverse, and use your tailstock.

robo hippy

[Cheryl A. Prince]

Ben, I use an Arbortech mini grinder (with it's standard cutting blade) to smooth out any rough chainsaw marks when I prep half a log for a face plate. Just a few sweeps back and forth removes any lumps or bumps left by the chainsaw.

[Steve Schlumpf]

I've used faceplates, worm screws and spades over the years but once I tried Jerry Marcantel's Chuck Plate (http://www.sawmillcreek.org/content.php?129-Building-a-Chuck-Plate) - I use nothing else. I like that it holds securely yet allows me to rotate the wood should I want to in order to get the best grain features.

[Prashun Patel]

I lately have also been using Jerry's chuck plate. I am still looking for a power planer. I think there's a time and place for it - especially if you are trying to use blanks close to the swing capacity of your lathe. If I had a nickel for every time my "12 inch" blank doesn't swing clear of the ways... A power planer is quick at shaving these places down.

[Michael Mills]

I use a 3-1/8 forstner bit (my faceplate is 3"). A faceplate sits flat or if using a worm screw the jaws of the chuck (with 50mm jaws) sit flat.
Maybe not the very highest quality but for drilling 1/4" deep should work for a long long time.

http://www.amazon.com/Steelex-D1025-Forstner-Carbon-Steel/dp/B000M87ZDA/ref=sr_1_6?ie=UTF8&qid=1326820531&sr=8-6 (http://www.amazon.com/Steelex-D1025-Forstner-Carbon-Steel/dp/B000M87ZDA/ref=sr_1_6?ie=UTF8&qid=1326820531&sr=8-6)

[Scott Hackler]

I lately have also been using Jerry's chuck plate. I am still looking for a power planer. I think there's a time and place for it - especially if you are trying to use blanks close to the swing capacity of your lathe. If I had a nickel for every time my "12 inch" blank doesn't swing clear of the ways... A power planer is quick at shaving these places down.

I have discovered that my better half likes to yell at me when I fired up the chainsaw to lop off the little bit of a large blank so it will clear the ways! (while on the lathe) Something about "idiot....blah blah blah....stupid.....kill yourself doing that...blah blah" I now have an electric version for this operation! :)

[David DeCristoforo]

I flatten mine by putting a piece of plywood on top and jumping up and down on it...

[Jamie Donaldson]

David, I don't believe that stomping works unless you're wearing combat boots!

[David DeCristoforo]

Thanx for that, Jamie. I figured I must be doing something wrong...

[Rick Markham]

My favorite is to use a forstner bit to make a flat spot right in the center of the blank (doesn't have to be deep, just enough to make a concentric circle, then I pound my drive spur into it and turn it round between centers, cut a tenon and rough shape the bottom curve, flip it around and mount it in the chuck, shape the outside between centers, then back off the tailstock, and do the finish cuts on the outside (to make sure it runs true after the tailstock is removed) and drill and hollow :)

if you do it that way, it doesn't matter what shape the wood is, it can be a whole manzanita burl. Since I have been doing it this way, I have NEVER lost a piece to the wormwood screw stripping out because of a punky spot or had a tenon break while shaping the outside. It has the added advantage for me that it removes the chuck from the equation, in the beginning, both sides of the piece can be equally accessed during the initial turning. Some pieces I use this to turn tenons on both ends depending on the design of the piece :)

[Jack Gaskins]

+100 for between centers............

[steve johnson]

I use most of the above methods. The makita power planer does a nice job of making a flat surface for a glue block. A friend scoots them across his jointer.

[Dale Miner]

So I am assuming that turning between centers is only a safe option on smaller blanks (>12")? I have some 18-20" blanks waiting to be turned, is a face plate the preferred method for these? One way I have done this in the past was use a forstner bit to create a level surface for the face plate to mount to. I also like the screw that came with my Stronghold, I am just concerned that I need a pretty flat surface, perhaps this isn't right...

I was watching an episode of American Woodshop where he used a power planer, that is what perked my interest. BUT, a lot of things he does on that show don't seem too kosher with me...

I mount just about everything between centers to start, including blanks that are at the diameter capacity of my 3520b. I have done started quite a few 18"+ diameter blanks between centers.

Some consideration as to the mounting is needed;

Remove the bark and cambium where the spur will engage the wood.

Inspect for defects in the area where the spur and the tailstock will engage the wood.

Lock the spindle and rock the blank back and forth while taking up any penetration into the wood with the tailstock (or, better yet, drive the spur into the wood before mounting).

Pay close attention to any changes in the blank while roughing and turning the outside.

Periodically stop and reinspect the mounting areas.

If the nub at the tailstock becomes much over 1/2" long in prepping the foot area, stop and remove with a chisel and repllace the tailstock on the now shorter nub.

Make sure the tailstock and headstock are fully tightened to prevent them slipping and the blank getting loose.

Use a spur that is sufficiently large for the size blank being mounted. 2 prong is best. The smallish 4 prong used for spindle work is not
adequate.

Hopefully, a picture of an 17" x 20" blank will attach.