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Marty Tippin
09-28-2014, 7:42 PM
Heres my second effort at a hollow form. Had a little trouble with the opening so it got redesigned a few times. Overall came out pretty good but I cracked the top while turning the base. Also found out my CA accelerator stains the wood. So it's not a "public" piece but another learning opportunity. Flame box elder, 8" tall and 5" wide, 1/8" thick or less. Finish is thin CA followed by Beall buff. Question: how smooth should you make the inside of a hollow form? 297480 297481 297482

charlie knighton
09-28-2014, 8:04 PM
coming along.....maybe try wider instead of taller.....say 6 w times 5 high on the next one
your continuous curve is much better on this one espically near the foot
inside smoothness is something that is personal.....I expect it will change over time, along with openings, finals, type of finish, whether you bleach box elder, etc......great thing about woodturning is you can change so much from one turning to another

Steve Doerr
09-28-2014, 10:09 PM
Nice looking HF. I've been there with the "redesign" process do to changes in the opening size.

The question of sanding the inside is one that you will find that has many varied opinions. A couple of things that I think will help you with the process: 1) the bigger the opening the more tempting it will be for people to feel the inside of the HF; 2) turners will always feel inside of a HF; and 3) if your fingers can feel it, sand it.

David Delo
09-29-2014, 9:59 AM
Well done Marty.

Steve Schlumpf
09-29-2014, 10:26 AM
Marty - I think for HF #2, you did a good job! Exterior curve looks pretty nice. Maybe next time try rounding the foot just a bit so that the form doesn't look like it was just cut off with a saw. Slightly rounding the side/bottom junction creates a small shadow line that gives the piece lift and adds to the overall appearance.

Question on your redesign opportunities: Do you know what you did that created the opportunity? Anything you want to share? It may help other beginning HF turners become aware of what can happen. Also know that you can turn a lid with finial or knob to complete the upper portion of the exterior curve. Always options out there to consider!

Having the inside of a HF as smooth as the outside has it's place - especially when entering the piece in a competition - but I like leaving the inside with a smooth surface by using a scraper (think wide cutter) but no sanding. I like folks to know that the piece is real wood, was turned on a lathe and not some mass-produced sculpture you can pick up at Walmart (nothing against Walmart!). Any area that fingers can reach around the opening, I do try to sand somewhat in order to make sure no one picks up a sliver! Now that would be embarrassing!

Looking forward to seeing HF #3!

Dennis Ford
09-29-2014, 1:09 PM
Form looks good, wood is really nice. The size is pretty ambitious for a second HF. About smoothing the inside; my preference is to scrape the inside as smooth as possible and only sand the inside of HFs with large openings (large enough for two or three fingers). I like to make the opening either large enough to get a hand inside (to allow sanding) or small enough for only one finger (sanding not needed).

Marty Tippin
09-29-2014, 2:06 PM
Question on your redesign opportunities: Do you know what you did that created the opportunity? Anything you want to share?

There were several issues at play - I think I made the wall around the hole too thin during my initial hollowing. Combine that with my clumsy handling of the Monster hollowing rig and the piece being turned in spindle orientation and cracking or tearing the small opening happens in the blink of an eye.

A question that I do have, however, is whether to hollow out the top of the form to finished thickness as soon as possible, or to delay that until the end of the hollowing. My logic in doing it early was the same as working on the edges of a green bowl - I wanted it done before there was any movement in the wood that might cause problems. But I've not really seen any movement in the piece since I finished it, so maybe that was an unfounded worry. I suppose the counter argument would be that leaving the area around opening a little bit thicker at first would make it a bit more robust while hogging out the rest of the interior.


The size is pretty ambitious for a second HF.

I wish you hadn't said that! I was happier not knowing that I should have had more trouble with something that size. (Though I will admit that getting the last couple of inches of the base hollowed out was pretty challenging - lots of chatter and hard to control the hollowing rig.)