Results 1 to 11 of 11

Thread: How do I cut bowl blanks?

  1. #1

    How do I cut bowl blanks?

    I have a Norway maple that is being cut down next week. How do I cut bowl blanks from this? How do I dry them after cut?

  2. #2
    Not sure if you have a chainsaw or band-saw or both. I consider a chainsaw a necessity and a large band-saw a luxury.
    * For blanks that you will rough out on the lathe SOON:
    Crosscut the log slightly longer than the diameter, then split the log through the pith (each side will make a bowl). If you have an adequate band-saw, put flat side down on table and cut a circular blank. The flat side can end up as the top of the bowl (or the bottom if you prefer a natural edge), either way turn away the wood near the pith so that no part of the bowl is closer than an inch from where the pith was. Some people cut away the wood near the pith before the blank gets to the lathe.

    * For blanks that you will attempt to store a while:
    Crosscut the log as long as possible, seal the ends and store it above the ground in the shade.

    Do not attempt to dry the blanks before turning unless you are OK with a high failure rate.
    _______________________________________
    When failure is not an option
    Mediocre is assured.

  3. #3
    What do you mean by " cut as long as possible"? I could just store the entire log to dry.

  4. #4
    Join Date
    Oct 2010
    Location
    Mountain City, TN
    Posts
    573
    Are you planning to wait until the wood is dry before you turn it?

  5. #5
    Join Date
    Feb 2008
    Location
    E TN, near Knoxville
    Posts
    12,298
    Quote Originally Posted by Matthew Curtis View Post
    What do you mean by " cut as long as possible"? I could just store the entire log to dry.
    You generally cannot dry a log successfully. Most will crack and split on the ends and down the sides long before dry inside. Large logs might still be wet inside after many decades.

    You forgot to provide some very basic information: What diameter are the logs and what size of blanks are you going to try to make?
    A bowl blank that is 6" in diameter and 2" thick can be managed far differently than one 16" in diameter and 8" thick.

    I process and dry a lot of wood, some of it into bowl blanks. I do have some 3-4" thick that have been drying now for over 12 years. I often wax these completely. I have more bowl blanks 2-3" thick - most dry without cracking if sealed properly. But MOST of the green wood I cut into smaller blanks for spindles, boxes, and other smaller items. These dry gracefully. I know nothing about Norway Maple - most of what I've dried are species local to TN.

    Large blanks are usually best turned while green, one way if you want it to end up round is "twice turned": rough out to the shape but left with a quite thick wall, dried carefully for months, then remount and turn to final shape and wall thickness. Some people like to turn to final wall thickness while green then just let the bowl warp as it will.

    As for storing a log, the other John Jordan (the famous one) said he gets the entire log if possible, stores it off the ground and out of the sun, and never bothers to seal the ends. When he's ready to turn something he cuts about 6" or so off the end and throws it away then cuts a blank to turn. Starting with a long log insures less overall waste. If you store a short log section end grain checks and cracks will eventually ruin it, even if sealed. The best advice I've read is never bring home more green wood than you can expect to turn in a few weeks.

    You can also store shorter log section for longer periods by submersing them in clean water (look up "ponding") or by freezing. Other ways usually end up as firewood. I don't know if Norway Pine will make good firewood.

    JKJ

  6. #6
    Quote Originally Posted by Matthew Curtis View Post
    What do you mean by " cut as long as possible"? I could just store the entire log to dry.
    Unless you want to wait years your best bet is to keep the logs as long as possible and end seal them. When you want to turn something cut off what you need to make the blank and re end seal the log. Rough turn the blank leaving the wall thickness 3/4 inch then do one of the methods to dry it (paper bag, or seal the end grain). Once its dry return it to the lathe to thin the walls and true it up.

  7. #7
    Where you are, the log should winter well. I would cover it and cut off blanks as you need them. When you bring them inside, turn immediately. The change in weather from outside to inside can make them crack. If you have some left over when spring and summer get there, get the log off the ground. I have a bunch of bowl turning videos up on You Tube, and include a couple on prepping from log blanks.

    robo hippy

  8. #8
    Well it looks like everyone has it covered but I will add. If you follow Dennis directions then rough out the bowls green leave about 3/4 thick "warning this can be very addictive" then put then in paper bags with all the shavings you just made and they will dry pretty quick. Seal the exposed end grain with green wood sealer or wax etc. Once dry turn again to a finished piece. I came along some cardboard 30 gallon barrels, i just stack them in there with the shavings and it works great. Before that I used paper grocery sacks and they work great too.
    Dean

  9. #9
    Join Date
    Apr 2018
    Location
    Cambridge Vermont
    Posts
    2,282
    Here's what I do. I accept that the end of the log will check unless I jump right on getting the log turned to a rough bowl blank. The checking usually doesn't go too deep so you'll loose 4" or so. Either end sealer or paint can help slow it down (I prefer using up leftover house paint when they are going to be left outside). I picked up some wire shelving from one of the box stores and place my bowl blanks on it in the basement. I haven't had any issues with cracking yet so I haven't had to resort to tricks like paper bags with wood shavings in them. My biggest problem is that I don't like deciding what I'm going to make and if it's a bowl what shape it's going to be when making the blank. That's where the band saw comes in handy. I'll either make the blanks that I cut from the log round and then seal everywhere the band saw blade cut so I don't need to put it on the lathe and rough it into a shape. But it's going to take a long time before it dries if left like that. But they are easier to move and store.

    My question to you is are you asking how to cut the log? I'm guessing that if you can store the whole log then you have a chainsaw and possible the means to move the log. What I have found is that the closer you get to the pith when cutting the blank (even if there's no checking) the more the blank will move near it. For smaller diameter logs you often don't too much of a choice or if you are trying to get the biggest possible bowl from the long.

    If you have a band saw then save the center section left over with the pith in it. You can also use a table saw but if you cut the pith out you can get some nice pieces for doing segmented bowls. Often that center piece is about 2" to 4" thick and from 10" to 24" long. Just like bowl blanks they can be cut and left in to dry.

  10. #10
    Join Date
    Feb 2008
    Location
    E TN, near Knoxville
    Posts
    12,298
    Quote Originally Posted by Dean S Walker View Post
    ...follow Dennis directions then rough out the bowls green leave about 3/4 thick "warning this can be very addictive" then put then in paper bags with all the shavings you just made and they will dry pretty quick.
    The 3/4" may need to be adjusted depending on the type of wood and the size of the bowl. Some wood shrinks more in one direction than the other (look up T/R ratio). A larger bowl can warp more than a smaller bowl made from the same wood. I've had some where I really wished I'd left the roughed bowl thicker.

    JKJ

  11. #11
    Join Date
    Jan 2004
    Location
    Fredericksburg, TX
    Posts
    2,576
    The general rule for green turning is to leave thickness 10% of diameter which usually works well. Some woods warp more and a little extra thickness will be required. I also like to remove a "pith slab" about 15% of diameter on larger diameter sections (say 12"+ diameter). That pith slab is quarter sawn material without pith and good for spindles, hollow forms, wine stoppers, pepper mills, etc. You can add a little to the 15% to get larger sections for hollow forms. Think beyond just bowl material.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •