Saturday, April 23, 2016

Wood Turning on the Table Saw Part Two

Part Two: Hogging the log

I made the choice to pair the cherry rim with the Box Elder rounds for a few reasons.  First I felt that the rounds were not as thick as I would have liked, I wanted a deeper bowl.  By adding the cherry lip I was able to increase the depth w/o having to later cut the entire thickness. 

Additionally I was digging the way the dark brown of the cherry contrasted with the white of the Box Elder.


For epoxy to glue the rim I was using Gorilla Glue brand five minute epoxy.  I picked that over a yellow wood glue because I wanted the flexibility of bond epoxy provides.  It took most of two tubes to attach the rim to both of the bowls.  Unfortunately I got a bad batch.  All of the stuff glued down with the first batch (tube) of epoxy came loose.  It never hardened and remained gummy more than 36 hours after mixing despite baking the wood at 120 degrees for 14 hours.  I have mixed a lot of epoxy in my day, trust me I mixed it properly, something was wrong with it.  Luckily for me it waited until after the bowls had been cut to come lose.  The entire rim of the first bowl had to be removed and thing pieced back together.  It sucked.

Hogging out a majority of the wood prior to cutting on the table saw is a nice modification from the last time I did this.  It sped up the process tremendously and lets face it, the press is safer so might as well use it as much as I can.

Pouring the epoxy in prior to cutting might seem like a waste, but it isn't.  Because I had some punk and deep cracks and I wasn't sure how those areas would respond to the saw.  Sealing the back of the cracks with tape, (I find the green FROG tape works well) I was able to fill those cracks and punky bits.  Later when the saw is cutting down through it will expose the filled cracks and they will have epoxy flush with the surface.  It looks cleaner.  Also ANYTHING you can do to minimize moisture movement and warping at this stage... do it.  The epoxy I was using was a counter top epoxy from Areo Marine.  This really isn't what it was designed for but I find the very thin nature of the mix gives me superb penetration which is important if you are trying to soak into rot.  The closer I can get to turning both bowls into blocks of plastic the better.  It will help minimize wood movement due to humidity changes.

Building my little hot box helps dramatically speed the epoxy set time.  It has a normal cure of 24 hours but I can cut that nearly in half with long periods of heat.  In the past I have found that long set times means the water thin epoxy can just run out the bottom.  I want it to soak in, not drip out.  Heat helps with that by skimming the epoxy faster than it would normally happen.

Friday, April 22, 2016

Wood Turning on the Table Saw Part One

PART ONE: Inspiration, Planning, Preparation and Selection

Almost everyone assumes turning a bowl is something you do on lathes.  How about turning a bowl more than 20 inches across out of a huge slab of highly figured hardwood?  Or turning a huge bowl with pockets of rot or bark?  Now that would totally take special and expensive equipment right?  What if I told you there is a way to create massive bowls without a lathe at all?  That is what we are doing here!

Using nothing more complicated than a table saw and some scrap lumber I turn some highly figured Box Elder wood into the two pieces you see above.  Before we start lets take a moment to talk about WHY you might think of doing it this way in the first place.

To start off with I do own a lathe but it is NOWHERE near large enough to tackle a project like this.  Trying to turn something this size on my under-powered machine would be an exercise in futility, but lacking the horsepower isn't the only reason someone might shy away from lathe turning.  Maybe it is a one off creation and you don't want to make the investment.  Maybe there is something inherently unstable about the stock you want to use, something that would make a 24 inch spinning disk potentially very dangerous.  Now I am the first to admit you are exchanging one type of danger for another, but I can also see where this method might be the only way to accomplish a task.  As a "for instance" I have always wanted to make something out of the gallery of a large carpenter ant nest.  For the life of me I can't think of a single way to turn that safely on a lathe but I think it COULD be done using my method.

In this first video I am just introducing the concept and there is little to add but still a few words of advice...

Picking your stock:  Chose wood that is dry and has stabilized.  Turning wood that is still wet will be a recipe for heartbreak.  It is going to warp and twist on you making it next to impossible to progress from step to step.  Make your selection carefully and then set it aside in your work space for a long time.  Give it a chance to acclimate.  If upon inspection you find that the material has warped, twisted bowed or moved in any real way give it a little more time.  Wait for it to stop moving.

Know your tools:  This IS your responsibility.  No one is in charge of your safety but you.  Later in the series I will be doing things that, and this is important to remember, YOUR TOOLS WERE NEVER DESIGNED TO DO.  Now that isn't to say they can't or wont but it bears remembering, pushing boundaries isn't without its own set of risks.  Only you know what you are capable of doing, what your skills allow and what your tools can handle.

Check out our first video here: