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Richard Jones
07-03-2011, 11:14 AM
OK, so I have this huge chunk of Bradford pear, about 15" dia, could get a 14" bowl out of it, thought it would be a good starter piece for my first HF, which I would like to attempt today.

What, if any, different blank prep steps/grain orientation/etc. are there for HF blanks vs. bowl blanks?

Many thanks, and wish me luck..........

Rich (where no man, at least in this house, has gone before) in VA

John Keeton
07-03-2011, 11:33 AM
Rich, is this a half-log? Does it include the pith? Is it dry? If I were doing a HF, I would prefer dry wood, but Steve and others rough turn their HFs and dry them before returning them. I also like to turn HF with side grain orientation, but others like to avoid the end grain on the sides and prefer end grain turning as it is easier to sand and finish.

Just some thoughts. A pic of your wood might help.

David E Keller
07-03-2011, 11:56 AM
I don't think there are any rules regarding blank orientation or prep, but there's good and potential bad with every option. Another option that John didn't mention is to turn green to final thickness and let it move. Pear is such a wonderful turning wood that you're gonna have a blast no matter what you decide.

Marc Himes
07-03-2011, 12:19 PM
I was at John Jordan's hollow form demo in St. Paul. He prefers to use green wood for his hollow forms and orients the top in the sapwood portion with the base closer to the pith. The top of the piece then can have a different color than the body.

Marc

Richard Jones
07-03-2011, 4:19 PM
Rich, is this a half-log? Does it include the pith? Is it dry? If I were doing a HF, I would prefer dry wood, but Steve and others rough turn their HFs and dry them before returning them. I also like to turn HF with side grain orientation, but others like to avoid the end grain on the sides and prefer end grain turning as it is easier to sand and finish.

Just some thoughts. A pic of your wood might help.

John,

Half-log, yes, slabbed up like bowl blanks, green as grass, pith cut out.

Rich

John Keeton
07-03-2011, 5:23 PM
Sounds like a bowl to me!! But, if you have 3-4" of thickness, you could easily do a nice HF.

Richard Jones
07-03-2011, 5:47 PM
Sounds like a bowl to me!! But, if you have 3-4" of thickness, you could easily do a nice HF.

John,

Yes, pretty big stuff, no problem to get 4+" out of them.

I think I'll try an end grain to start, just to see what happens with me and the Monster.........

R

John Keeton
07-03-2011, 6:00 PM
Use the smaller cutter for hollowing and the larger one for cleanup - I think it will go better for you.

Faust M. Ruggiero
07-03-2011, 6:31 PM
Richard,
You can either rough turn and put it away to dry or you can final turn right away. Both ways are fun and produce different results. Bradford Pear will shrink quite a bit. If you turn to finish (once turned) the form will distort and become oblong. Not a bad result but not pleasing to everyone. However, it does allow almost instant gratification. Rough turning your first hollow form is a drag especially if you are trying out new tools. If you decide to do a "once turned" hollow form, budget enough time to finish it, including removing the tenon. Once they are thin, they dry before your eyes and change shape. That's why lots of turners prefer dry wood.
Have fun and remember, it's only wood.
faust

Wally Dickerman
07-03-2011, 6:33 PM
You've had sound advice so far....My suggestion is to opt to turn your first HF using a much smaller blank. A 15 inch blank will require an awful lot of hollowing. Save the B pear for later or cut it into 2 blanks for you first 2 HF's.

Richard Jones
07-03-2011, 9:00 PM
Thanks guys, still haven't taken the plunge, so to speak, will probably do it tomorrow on the 4th. Wally, I was going to go way smaller, looking for some w x d sizes now to try and get a start. 15" IS too big for me for now, maybe forever........

If I choose to rough turn this and allow it to dry before re-turning, is the 10% rule still in effect?

Rich

PS Oh yeah, nobody told me how WET this stuff was!!! I thought some elm I roughed a few weeks ago was wet, but this stuff is outrageous. It was cut on Wednesday of this week, I slabbed some of it up this morning and turned and cored a big & smaller bowl. I mean water dripping from everything wet. Crazy...............

Steve Schlumpf
07-03-2011, 9:47 PM
Richard - as far as grain alignment, if you start roughing out between centers, you can rotate the blank once you see what grain you have to work with. I try to make sure that whatever the best feature the wood has to offer ends up on top of the HF - so rotate the form as needed to make that happen.

I twice turn all my HFs and I follow the 10% rule! Good luck! Looking forward to seeing your first HF! Have fun!

Thomas Canfield
07-03-2011, 10:19 PM
Sounds like several issues here. I like turning Bradford Pear both end grain and side grain. The end grain usually has the pith and checks easily and turns easily. Holding a 4"+ D x 15" long piece in a chuck would really test my pucker factor for a fitst, and would recommend a steady rest for hollowing since a catch is almost certain and a wet tenon will not hold well. You might consider cutting one chunk in half and working on a 7.5" long piece for you first hollow form You will not have the pith to worry with, but the different growth rings will still have some distortion in the drying process. Turning to finish green works best, and the wood is drying all the time you turn. It will sling a bunch of sap at start. DO NOT REMOVE THE CHUCK UNTIL READY TO PART OFF to help prevent any checking in the bottom. You can wet sand the green wood down to about 220 and then let it dry before doing final sanding and finish.

If you turn a bowl, I usually would turn green to 10% wall thickness (1.5" for 15" D), coat with Anchor Seal, and let dry for about 6 months or so checking weight loss. Returning the dry bowl will give you some really nice tight grain wood to finish, and I like an oil finish.