Turning a Manzanita Bowl Root Ball


This is the first time I've tried turning something from Manzanita.
The piece is sold as a burl. It looks more like a root ball to me.



I look a little close and find the burl is packed with dirt and spend a while gouging it out.

I started drilling holes for a face plate and the drill bit broke (piece sticking out of the burl surface.

Hmmm, hope this isn't a harbinger of bad things to come. This stuff must be pretty hard.



It took a while to mount the face plate.  I burned up one drill bit and broke a couple screws. 

I usually use drywall screws. They are inexpensive and grip very well.



The burl is being turned at 100 rpm.  I am gouging a flat spot so I can mount the tail stock.



It took an hour or so to get the burl reasonably round. I don't think this is going to be a bowl in the normal sense.

It looks like this is going to morph into some kind of artsy piece.



Some nice red color is starting to show through. I decided to stop here and start cutting a tenon.



The tenon is cut so the bowl (?) can be reversed. This stuff doesn't look exactly stable.

I don't know that I am going to do any more turning  on this piece.



I am going to hollow out the inside of the burl with a power tool.  
A grinder with a chainsaw blade attached to it makes a great time saver.

You need double face protection with this device. 

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More Detail  on the Disk

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Anyway, back to the Root Ball:

Ensure you grind in a direction where you can contain the chips.



Twenty minutes later I hear strange noises. Further investigation reveals a void filled with dirt and a rock.

I use an awl to clean out the space.  It looks about 2" deep. This is starting to get interesting.

To be continued....



Ok, it's two days later and marginally cool enough to work in the garage.

Some areas are close to 1" wall thickness so it's time to get the outside of the bowl closer to finishing.



I changed out the chainsaw disc and switched to a 60 grit flap sanding disc.  This works pretty well
but you do have to be careful not to gouge the wood.

I did try a 120 grit flap sanding disc but it is to fine, spins to fast and burns the bowl surface.

It is too hot in the garage to do anymore today.




The bowl interior was sanded using a 120 grit disc attached to a sander.  It took a while to
sand out the gouges.  Plan on taking a shower after sanding - lots of red dust.




The bowl exterior is sanded down to 120 grit.
Note:  I am not turning the bowl.  I am using the chuck to hold the bowl while sanding.



Tools:

Left Side - 4" sanding disc on an electric drill (did not work for the intended purpose).

Bottom Center: Chainsaw blade cutting disc from Lancelot and Squire, which worked fabulously.  

Right Side:  60 grit flap disc on a 4" angle grinder (this did not work well at all).




My sanding method worked pretty well on the bowl outside.  There was a problem on the inside where the hole filled with dirt and rocks is.  I sanded down too far and created a divot around the hole.

So,  I' am in the process of turning down the inside using the lathe  using a slow speed .  Manzanita seems to flake off the
tool rather than peel off. I am a bit concerned about the outside rim.  It looks like if  I catch the tool once, a chunk of the
bowl is going with it.



Several weeks later, the inside is re-turned.  It wasn't that it was that hard, it was because it was getting too frigging hot in
the garage to spend any amount of time in there.



The bowl is much thinner and miracle of miracles, no big chunks broke off.
I am going to hand sand the inside - when it gets a little cooler.



Inlay arterials for this bowl I thank are a must., to add stability if nothing else.   Integrity looks a little iffy.



There were half a dozen or so spots that looked like reinforcement was necessary.
This will dry a day or two before continuing on.



I didn't like the way the bowl bottom looked.  It needed a bit more shape. I took about  1/4" off and ended up exposing
another large crack which destabilized about a third of the bowl, hence the additional inlay.

It's going to be real interesting to see how this turns out.  It's either going to look very attractive or it's going to look like
some kind of clash of  the primary colors freak show.



Well, here it is.  It actually looks pretty good.  It is finished with True Oil.
The pattern of the inlay follows the chunk of bowl that looked about to crack out.

The stuff is a pain to turn and sand, but the end product kind of makes it worth it.  

Worth it to do another?  Maybe.......

Merry Christmas, April!

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Cutting Disc Detail

The tool described here is from King Arthurs Tools

This was described this as a second rate tool of choice (why doesn't that surprise me).

Not being a total idiot and before I even went down this road, I took the tool down to one of my machinist buddies who also
cuts a lot of wood and asked him for an opinion.  He looked at it, tried it out and his thought was that while it was well
constructed, PPE was a must and he was interested in seeing someone who had a marginal clue as to what he was
doing try it out.

I, being the marginal person in question mounted a spalted maple log, bark and all on the lathe and went to work.
20 minutes later, I had a bowl blank.  It was impressive.

I then re-mounted the blank and some 15 minutes later had the blank hollowed out.  We both batted an eyelash at that.

Problem  #1

When I first started this exercise I was wearing a short sleeved shirt and regular working gloves.  Chips from the
evil tool were hitting my arms at high rates of speed which left undesirable blotches on my skin. It ended up looking
like a mild case of road rash.  I switched to a long sleeved shirt and gloves with gauntlets.  

Problem solved.

Problem  #2

This tool sent chips everywhere.  A dust collector is worthless in this circumstance.
I needed a method for containing the chips.  I screwed several eye hooks into the ceiling and draped a couple really
cheap sheets from Walmart around the lathe.  

Think shower curtain, which also acts as a shock abosorber for flying chips.

In conjunction with this, use double face protection.   As I said, these chips come off at high rates of speed.   It
would be very easy for one of those chips to bounce off your face, on to the inside of your safety glasses and into
your eye.   Same principle as when grinding metal in an enclosed space.

Use safety glasses and a face shield.

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Notes

Note 1

The cutting tool is recommended only for specific grinders and they are listed.  Ensure you have a grinder that matches
the specs which are listed in of all places, the manufacturers instructions.  A grinder meeting these requirements is
an inexpensive item.  Also, there are specific notes as to how to adjust the grinder safety guide to accommodate the
cutting disk.

Note 2

Hearing protection is a must.  Do not use this tool without good hearing protection.  I know what I am talking about.
I spent the majority of my adult life working around machinery death to all things auditory.  My hearing at 52 years of
age is as good, if not better than many people in their 30's and it is directly a result of a conscious decision to protect
my hearing.

Being raised on heavy metal,  the retirement homes are going to just love me.  Of course, most my senior neighbors
will probably be deaf anyway so that may be a moot point.

Note 3

You need to be focused on what you are doing.  If anyone has worked with a hole saw attached to a 1/2" drill motor,
you know what I am talking about.  Use a wide legged stance, keep a firm grip and stay away from the grinder.  
Kick-back would not be a pretty thing.

Note 4

Do NOT think about the need for turning speed.

I use the Shopsmith and a speed reducer when turning bowls using this tool.  What I do is this if I am using a log:



A.  Get it marginally round.  This is a piece of Osage Orange.





B.  Mount the faceplate to the lathe.

C.  Roughly round the log manually, turning it by hand if you can't get the lathe speed slow enough.
      In this case that was unnecessary. It was balanced pretty well.



D.  Start the lathe at the lowest speed (I use a speed reducer) getting it rounder.
      Increase the lathe speed as the log gets rounder.   This took about 20 minutes.



E.  Remove the tail stock support and this flat.



All told, this took somewhere around half an hour.   The blank is now ready for conventional tools.

Turning the inside of the bowl.

Follow the same steps as mentioned above but turn a bit faster initially.  Go in as deep as you can.  This saves
lots of turning time.

Switch back to conventional hand tools when you have met your objective.



A work in progress.

Closing Comments

One of the primary reasons I particularly  like this cutting disk  is the tremendous amount of time that can be saved  using such a device and time for me is an issue - never enough of it. Green Wood These  disks are also great when you unexpectedly get hold of some nice chunks of green wood which might just make for some nice bowl blanks and time is something of an issue.   Spalted Woods Spalted woods you have to be careful with. If they are too soft or pithy, these blades will take out way too much, way to fast.  This will create irreparable divots. More Detail on the Chainsaw Cutting Disk: