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whelp. Ive developed this unhealthy addiction to making transparent lampshades here recently and have decided to try to break several personal bests on this massive piece of shagbark hickory I picked up off the wood lot. I'm placing odds of success at around 10%. The piece is 14 inches wide and 8 1/2 inches tall. The main difficulties thus far have had to deal with speed. After getting a rough form and clearing out some of the top only then did I feel comfortable turning the speed up to the second setting and the going has been SLOWWWWWW. I started this morning and the final picture is where I am at now. The major difficulty was the first half of the inside. I had to take tiny cuts to keep it from vibrating that far away from the headstock. I think that if I cant successfully get the piece up to the 3rd setting which is 800 or 600 rpm? for final turning to super duper thin then it needs to be a bowl. I have never attempted a natural edge shade and the sap wood has a touch of punk and spalt to it which adds to the challenge. Pretty sure this also sets a weight record... it took both me and my roomy to get it up on the headstock. Ive hollowed to a uniform 1 1/2 -2 inch thickness to allow some base stability for when I start the top. My main concern is the bottom though. Even with the rest inside as far as possible I don't think the bowl gouge is going to have enough stability to make accurate cuts so far away from the rest. I am considering using one of my long bore hollowing tools but am concerned that scraping will cause too much tearout. WHEW sorry to blather on guys, I'm just amped on this one! I think that above all the other potential causes for failure lack of patience is gonna be the number one killer... Any advice on tools or procedure here would be appreciated:yes: happy turnin all,
Bond
 

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At the first AAW symposium I attended I ran the video camera for Peter Block (I hope that's spelled correctly). It was the first time I saw anyone turn a lampshade. He used the bowl gouge in shear scraping mode to get to the final thickness (thinness). He used a light bulb outside and judged the thinness by matching the color of the wood as it glowed.
 

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Shrink wrap works well to hold things together as you turn, not tight or you will crush the piece. Also your best bet is to turn the wood al at one session if you do it in more than one turning the movement from the wood drying out will get the bowl our of round. Use a squirt bottle with water in it to help keep it wet. Good luck look forward to seeing the piece, even if something should happen to it show us it all part of the learning curve

Jerry
 

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I used a 1/2 inch finger nail gouge an my Eleworth for mine but I let my wood soak in dish water for a week before I do the final turning after its dry an the let it sit in Watco natural or tung oil for 3 days , but it works for me I'm self tought on shades some even tho Tom help some
 

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AWWWW SHOOT... I spent the past two days babying this sucker. I was about half way through the thinning process and made a mistake. It was not the mistake I thought I would make (when is it) but it happened and half the piece exploded. I was ready to be meticulous, to ensure the wall thickness was even,thin and perfect. But what I was so focused on the thinness and the tiny cuts and the sharpness that I made a rookie blunder. I was truing up the next section of the outside and forgot for a moment that I had waxed the lathe bed the week before and forgot that the banjo was sliding quick and as I untightened the banjo and attempted to reposition it the far end rotated unexpectedly toward the headstock and slammed into the piece shattering it.:censored::censored: :censored::furious::furious::furious::furious::furious: I gotta post this because I need to move forward and learn from these mistakes. A great deal of what went wrong here was not just the banjo sliding into the piece but my mental state while working. I was so focused on making PERFECT cuts and having PERFECT wall thickness and sharp tools that I forgot about the simple basic gestures that go into creating a piece. Carefully adjusting a tool rest is rarely on my mind. If you accidentally bump a thick piece it bounces off, maybe there is a little dent but nothing you cant correct on a natural edge piece that is like 1/16-1/32 of an inch thick however the damage is catastrophic. I think posting a kind of step by step and analysis of how I went about this will at least put some thoughts in my head of how to course correct in the future. The banjo thing was unfortunate but only half the piece is gone. Usually ide huck it in the yard and fume but there's still a piece here and it's not the woods fault. My mind needs to be malleable and adapt to circumstance. Sure it's not the hulking record I was hunting but there is still a piece and a challenge left. This step by step is going to be long but it's more for me than for public consumption.
-I used a faceplate to start with and shaped the outside and tennon and then moved to a chuck. If I attempt one this big again I will not put it in a chuck. Because the lathe speed had to be low during the roughing the tennon was difficult to form and I think it may have played a part in stability factors later on. The tennon appeared to be seated in the chuck properly and the jaws were snug against the foot but I still think using a faceplate all the way through would have been a better option. Maybe the chuck worked just as well but it comes down to confidence.
- One of the biggest challenges was, of course, the size. Dealing with such a big wet piece meant that I had to keep the lathe speed at 200 for shaping the outside. I had to maintain this speed through half of the hollowing process as well because the difference in weight in the natural edge was causing wobble at 400 rpm. I used the tailstock for support for as long as the angles would allow. I saw a video where a guy hollows with the tailstock in and then cuts out the center part with an electric chainsaw. I considered something like that but it made me nervous sticking chainsaw inside a bowl near a bunch of metal so I decided to just use the bowl gouge. Hollowing the center at 200 rpm was no fun but I did it anyway. I suppose I could have saved some time with a drill bit but I didnt.
- After half of it was hollowed to a 2 inch wall thickness I ramped the speed up to 400. The lathe dealt with this just fine and there were no significant wobbles at this speed. my main goal was to get the piece to a place where I could go to 600 with no wobble but I had major concern that the thinner I got the less support I would have. I also worried about the wood movement at a thinner diameter This was probably a mistake. I think I could have taken the wall thickness down to an inch and it probably would have been fine and helped a great deal in creating much less wobble. To be honest I also got impatient because Id be turning at such low speeds for hours on end and was ready to get something done! while well intentioned I that kicking the speed up at this point adversely effected the rest of the process.
- I kicked it up to 600 rmp. At this speed the piece was wobbling not TOO bad but it was still shaking. At the time I didnt think of it but this probably caused me more hassle than I can realize. If the lathe has a wobble you are not getting consistent cuts. Consistent cuts means an even surface and an even surface mean a more consistent wall thickness. I know it sounds like a ridiculous thing to do but I kept on going at 600 rpm and spent the next hour trying to get a perfect outside surface which of course was just not possible because the piece was too just too heavy.
- I did the best I could to true it up with the wobble and though I think I did an alright job at making a smooth surface there is no doubt in my mind that it would have been much faster had I taken to time to reduce the weight.
- I started working on the inside I cleared about half an inch of waste at a time inward and worked on the wall a half an inch at a time. There were two types of cuts I tried on the inside to get the piece really thin. The first was a sheer scraping cut and the second was your typical bevel rubbing cut. on the natural edge section I think I spent way too much time with the sheer scraping cut. I was concerned and focused on not plunging though the wall but in retrospect I should have removed more of the waste with a bevel rubbing cut. Shear scraping removes such a tiny amount and dulls the edge faster. I was kind of worried about how stable the sap wood was because spalting was present but in retrospect I would have made an earlier assessment that the sap wood was stable enough to take the bevel rubbing cut to a much thinner diameter than I did.
The lathe wobble and the fact that it was a natural edge did not help with the sheer scraping cut which relies on a pretty even surface. I tried out using a sorby sheer scraper which actually worked pretty well but kept on using my bowl gouge. It's odd that I do this but I notice that sometimes Ill stick with a bad process bad decision or whatever because of environmental circumstances. Meaning Im tired of hollowing at a slow speed or Im more comfortable with my bowl gouge. I think a great deal of what I need to focus on in turning is to focus on what works best. I had a pretty big drive for an end result and find that many times that is all I am thinking about. Sometimes that drive to get to the end quickly ends up prolonging the process by hours or days because I don't take ten minutes to step back and walk myself through what's going on.
-as I got past the natural edge I began using the bevel rubbing cut much more. The piece was not wobbling nearly as much and I found that I could use this cut almost exclusively and then do a little sheer scraping if there were tool marks.
- I kept the piece wet especially when nearing the final thin ness. This really helps the sheer scraping do its job properly. I also put a plastic bag on it overnight which kept the piece nice and wet for the next day.

Just realized this was not a step by step but more a "things not to do" list. Ah well... maybe Ill make a step by step when I get super duper good at it. It's helped me internalize some of this stuff though. Anyway... Im gonna give the remaining half an chance. Sorry for ramblin on, happy turnin,
Bond
 

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:furious: It happen to me to a couple time then again I was a slow learner :laughing::laughing: But we all make the mistakes an learn from them good luck on your next one I going to do a NIP one next an I don't have to soak it so it will get done quick an sorry for the lost of the wood for ya
 

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Discussion Starter #7
big cougar, Norfolk island pine would be so cool for a lampshade! I did one with some FBE and the result is pretty freakin cool. Shines through the light wood and is dark in the dark areas. Next time I have some money I may order some of Texas Timbers stock... Ive had plenty with decent amounts of flame but his look just crazy.
 

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big cougar, Norfolk island pine would be so cool for a lampshade! I did one with some FBE and the result is pretty freakin cool. Shines through the light wood and is dark in the dark areas. Next time I have some money I may order some of Texas Timbers stock... Ive had plenty with decent amounts of flame but his look just crazy.
I had a piece an was nice but it split on me after a week I did a NIP one already an also sweet gum an Sycamore an they turned out great the FBE I drilled some holes on each side an ran some lace throw it an it sold quick , go figure on that stun me in the shop when the lady wanted it an payed cash :laughing::laughing:
 
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