ÿþ<HTML> <HEAD> <TITLE>Turning a Hollow Elm Sphere</TITLE> </HEAD> <BODY> <CENTER><table border=7 BORDERCOLOR="#000099" BGCOLOR="#FFFFCC"> <tr> <TH nowrap width=400><H2>Turning a Hollow Elm Sphere</H2></TH> </tr> </table></CENTER> <P> <FONT FACE="Arial"> <H4> This page is to take you through the steps I used to turn a hollow elm ball. As mentioned on my 2010 page, the ball is hollow with a ¼" wall thickness. <p> I don't show the steps I used to round out and finish the ball, but basically I used the old time method of holding the ball between two cup shaped centers and turned away the "shadows" as I changed its orientation between the centers. I found out it is a lot easier to do with a small ball. This large sphere was a challenge.<p> <Center> <IMG SRC="smileysparkle.gif" > <p> <TABLE BORDER=7 BORDERCOLOR="#000099" CELLPADDING=20> <TR><TD WIDTH="60%" VALIGN="MIDDLE" COLSPAN=3><CENTER> <IMG SRC="The Rough Blank.jpg" WIDTH=800 HEIGHT=600 ALT="The Rough Blank"></TD></CENTER> <TD WIDTH="60%" VALIGN="MIDDLE" ROWSPAN=1><H4><FONT FACE="Arial"> Here is the start of the process. When I saw this section in the large burl I saw the bark inclusion that ran through it and the idea instantly popped into my head to turn a hollow sphere from it, so I sawed out a basically square block.<P> This shows the block, about 14" per side, sitting on the bed of the lathe.<p> </TR></TABLE><P> <TABLE BORDER=7 BORDERCOLOR="#000099" CELLPADDING=20> <TR><TD WIDTH="60%" VALIGN="MIDDLE" COLSPAN=3><CENTER> <IMG SRC="Starting the Ball.jpg" WIDTH=800 HEIGHT=600ALT="Starting the Ball"></TD></CENTER> <TD WIDTH="60%" VALIGN="MIDDLE" ROWSPAN=1><H4><FONT FACE="Arial"> To start with, I mounted the block between centers with the bark inclusion running in the same axis as the rotation of the piece and started turning it into a rough sphere, starting on the right side.<p> It is important to note that I stand opposite the tailstock to turn this part and cut from the center outwards. By doing so I am cutting across the grain, not into the end grain, and I am safely out of the way of any pieces that might fly off. I use a fairly slow speed and take a light cut, but at any speed a piece of bark can hurt if it flies off and hits you. This blank was pretty rough and I do not take chances at the lathe if I can avoid it. I rarely stand in the line of fire at the lathe, as even an innocent looking piece of wood can suddenly shed a chunk, especially at high speeds.<p> </TR></TABLE><P> <TABLE BORDER=7 BORDERCOLOR="#000099" CELLPADDING=20> <TR><TD WIDTH="60%" VALIGN="MIDDLE" COLSPAN=3><CENTER> <IMG SRC="Turn the Other End.jpg" WIDTH=800 HEIGHT=600 ALT="Turn the Other End"></TD></CENTER> <TD WIDTH="60%" VALIGN="MIDDLE" ROWSPAN=1><H4><FONT FACE="Arial"> Now I am about to switch to the other (left) end of the blank. Note that I am using a Steb center as a drive center. It was perfect for this task This time I am able to stand opposite the headstock and use a pull cut from the center outward - once again for safety and to avoid cutting directly into the end grain<p> </TR></TABLE><P> <TABLE BORDER=7 BORDERCOLOR="#000099" CELLPADDING=20> <TR><TD WIDTH="60%" VALIGN="MIDDLE" COLSPAN=3><CENTER> <IMG SRC="Ball is formed.jpg" WIDTH=800 HEIGHT=600 ALT="Ball is formed"></TD></CENTER> <TD WIDTH="60%" VALIGN="MIDDLE" ROWSPAN=2><H4><FONT FACE="Arial"> So here is a basically round shape with a tenon on each end. I did not worry too much about the shape at this point because the wood was going to have to sit and dry and it would warp anyway. I just wanted to get it thin enough to dry more quickly.<p> </TR></TABLE><P> <TABLE BORDER=7 BORDERCOLOR="#000099" CELLPADDING=20> <TR><TD WIDTH="60%" VALIGN="MIDDLE" COLSPAN=3><CENTER> <IMG SRC="Large Half.jpg" WIDTH=800 HEIGHT=600 ALT="Large Half "></TD></CENTER> <TD WIDTH="60%" VALIGN="MIDDLE" ROWSPAN=2><H4><FONT FACE="Arial"> Here is the large half, mounted in the Stronghold chuck by a tenon. All I had to do was take the round-ish ball from the previous frame, stick a screwdriver into the bark inclusion and twist to get the two halves to pop apart.<p> </TR></TABLE><P> <TABLE BORDER=7 BORDERCOLOR="#000099" CELLPADDING=20> <TR><TD WIDTH="60%" VALIGN="MIDDLE" COLSPAN=3><CENTER> <IMG SRC="The Termite.jpg" WIDTH=800 HEIGHT=600 ALT="The Termite"></TD></CENTER> <TD WIDTH="60%" VALIGN="MIDDLE" ROWSPAN=2><H4><FONT FACE="Arial"> This is the large half partially hollowed using the Termite, a round cutter made by Oneway. I have the Termite mounted in a 5/8" shank that I made myself. This is pretty rough inside, but I wasn't going for "pretty" here. I just wanted it partially hollowed so I could put log end sealer on it and set it aside to dry.<p> </TR></TABLE><P> <TABLE BORDER=7 BORDERCOLOR="#000099" CELLPADDING=20> <TR><TD WIDTH="60%" VALIGN="MIDDLE" COLSPAN=3><CENTER> <IMG SRC="Close Up of Termite.jpg" WIDTH=800 HEIGHT=600 ALT="Close Up of Termite"></TD></CENTER> <TD WIDTH="60%" VALIGN="MIDDLE" ROWSPAN=2><H4><FONT FACE="Arial"> This is a closer view of the Termite cutter. I have been using the Termite since I started turning about 14 years ago. Many woodturners are afraid of the tool and refuse to use it, but I have found it my "go to" tool for many purposes. It is designed to cut end grain, but I find it useful on burl and side grain as well, but it is more prone to plugging on stringy or splintery woods. The tool can deliver nasty grabs, so it takes practice and patience to learn to use. I have not had a catch with the Termite for years, and highly recommend this useful and tough tool. I've tried all the modern derivatives and alternatives and still prefer my Termite.<p> </TR></TABLE><P> <TABLE BORDER=7 BORDERCOLOR="#000099" CELLPADDING=20> <TR><TD WIDTH="60%" VALIGN="MIDDLE" COLSPAN=3><CENTER> <IMG SRC="Small Half Hollowed.jpg" WIDTH=800 HEIGHT=600 ALT="Small Half Hollowed"></TD></CENTER> <TD WIDTH="60%" VALIGN="MIDDLE" ROWSPAN=2><H4><FONT FACE="Arial"> Here is the small half hollowed out. Following this step I waxed (log end sealer from Lee Valley) the halves and put them aside. I made sure to avoid getting any end sealer on the rough edges where the ball was split apart.<p> </TR></TABLE><P> <TABLE BORDER=7 BORDERCOLOR="#000099" CELLPADDING=20> <TR><TD WIDTH="60%" VALIGN="MIDDLE" COLSPAN=3><CENTER> <IMG SRC="Halves Glued Together.jpg" WIDTH=800 HEIGHT=600 ALT="Halves Glued Together"></TD></CENTER> <TD WIDTH="60%" VALIGN="MIDDLE" ROWSPAN=2><H4><FONT FACE="Arial"> Here is the piece, months later, after it was dried. I cleaned off the loose bark from the edges, turned the tenons round and true, then turned the insides of each half smooth and perfectly round. I used a cardboard template to ensure it was round. The inside was sanded and then given a coat of WOP (wipe on poly) before gluing the two halves together.<p> I used 5 minute epoxy mixed with coffee grounds for the glue job. The reason - it is hard to tell the difference from bark, and the space between the halves was now varied due to shrinkage and the loss of most of the original bark in the inclusion.<p> To start with, I gave each side a thin coat of epoxy and put the two pieces together using the lathe as a clamp. I used a thin coat to avoid any runoff of the glue into the inside of the piece. After it was cured, I did the rest of the gluing in sections,1/8 of the way around at a time. I would put the epoxy into the crack, put a piece of tape over the crack and rotate it to the bottom so the glue would flow to the outside and held there by the tape. It took awhile, but it worked. <p> At the last section I slid two ball bearings into the piece and finished the glue job. I did this to avoid having the ball bearings getting stuck into the glue line.<P> </TR></TABLE><P> <TABLE BORDER=7 BORDERCOLOR="#000099" CELLPADDING=20> <TR><TD WIDTH="60%" VALIGN="MIDDLE" COLSPAN=3><CENTER> <IMG SRC="Elm Burl Hollow Ball Completed.jpg" WIDTH=800 HEIGHT=600 ALT="Elm Burl Hollow Ball Completed.jpg"></TD></CENTER> <TD WIDTH="60%" VALIGN="MIDDLE" ROWSPAN=2><H4><FONT FACE="Arial"> Here is the piece, finished. It is a conversation grabber, especially when I encourage people to pick it up and they discover how light it is. Their first question, "How did you do that?"<p> Now you know<p> </TR></TABLE><P> </TD></TABLE><P> <P>&nbsp;</P> <P>&nbsp;</P> <P>&nbsp;</P></BODY> </HTML>