whoops John already posted whilst I was typing
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| Author: | Andy Zimmerman [ Tue Nov 22, 2005 3:07 am ] |
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Hi This question will clearly show my inexperience. Why do some people use teflon strips in the purfling slot when gluing down the binding with shell? Why can't you just glue the shell with the binding? Also, do you ususaly route the purfling slot to exact height for shell or a little shallow and sand a bit of the shell or a little deep and sand a bit of top to make it flush Andy |
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| Author: | John How [ Tue Nov 22, 2005 3:17 am ] |
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If you were to cut the shell to the shape of the guitar, it would be easy to inlay the purfling when you glue on the binding. But most don't, they use straight strips that are cracked or forced into the curved slot. It is just easier to do that way and with abalone the cracks blend with the lines in the shell and become pretty much invisible. It is much easier to glue the binding and teflon on and make a channel before puting the shell in place. Then installing the shell takes just minutes to do and you will have fewer issues. After the shell is put in place flood it with CA and your done. Since the best color is usually at the top of the shell or you don't really know what the color is below the surface, I usually try to set the channel depth to the exact depth of the shell. Then I have little sanding to do. |
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| Author: | RussellR [ Tue Nov 22, 2005 3:19 am ] |
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Hi Andy The reason for the teflon strips is you glue everything up and then you have a channel for your shell laminate, with the laminate you can then gently break the shell laminate into the channel, which means you can use all straight strips. I leave mine just a touch proud as you don't want to sand the laminate too much as it can change quite radically. |
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| Author: | RussellR [ Tue Nov 22, 2005 3:20 am ] |
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whoops John already posted whilst I was typing
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| Author: | Andy Zimmerman [ Tue Nov 22, 2005 3:44 am ] |
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So you use straight pieces and just break them into the curved shape of the body????? Andy |
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| Author: | Dave Rector [ Tue Nov 22, 2005 3:47 am ] |
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[QUOTE=azimmer1] So you use straight pieces and just break them into the curved shape of the body????? Andy[/QUOTE] Yep. |
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| Author: | tippie53 [ Tue Nov 22, 2005 3:58 am ] |
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I use all straight strips and as john How pointed out why teflon is used. The one trick I found is that white elmers glue is what I use to glue in the pearl then super glue to fill any voids as pearl is a natural material and will need some touch up once in a while. I don't use superglue any more on spruce to glue in the perfling as I have a problem with it turning the spruce yellow over time. It is fine as a drop fill john hall |
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| Author: | Daniel M [ Tue Nov 22, 2005 4:32 am ] |
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Thanks for posting this question Andy. I've been running this process around in my head & want to give it a try on my next guitar. I have always thinned my tops around the edges after the bindings are in place. I guess that if you are using shell, you have to do your thinning before you cut the binding ledges to prevent oversanding the shell. You'd have to be very careful not to scratch the top while leveling the bindings. I'd be very interested in hearing how other folks get around these issues. What is the sequence used in getting the top thinned & the bindings, purflings & shell all levelled without sanding through the best colour on the shell? The teflon strip appears in the catalogues, to be much thicker than shell... Do you put a filler in the void to raise the level of the shell strips? Many in advance "thank yous" for any advice you folks can offer! Dan'l |
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| Author: | arvey [ Tue Nov 22, 2005 4:42 am ] |
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I am an exception here. I use both curved and straight shell pieces and just glue them right in without teflon. I used teflon on a rossette once but couldn't see the advantage. Just one more step IMHO |
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| Author: | csullivan [ Tue Nov 22, 2005 4:59 am ] |
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Just to confuse the issue: I have used the teflon strips to create a channel for the shell and that works great. I then cut my shell into short sections (vary from about 3/8" to 3/4", depending on whether it's a sharp or shallow curve) and actually shape the 2 long sides to a curve to fit into the channel. I then make flat ends and butt the pieces together. It takes forever, but they look great because there are no voids. When I need a channel that isn't the width of the teflon strips I route out the recess to the full width of purflings, shell, and binding. I then glue in the inner purfling. Next I shape only one side of the shell piece to conform to the curve and glue it in, leaving it slightly wider than finished size. After all the pieces are glued in, I trim the outer edge of the shell with the router, going slowly and carefully, so there's no chipping of the shell. This gives me a nice consistent edge to glue in the next purfling or outer binding. I"ve tried both methods of either leaving the shell slightly proud of the surface or slightly below the surface. Now I try really hard to get it as dead level as I can, but inevitably there will be some leveling to do. I sand to get the bulk of it, but scraping works best to finish it off. Shell actually will scrape fairly well, especially if there are no (or few) voids to catch the corner of your scraper. Scraped shell really seems to shimmer in the light. Just my quirky way, but it works for me. Craig |
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| Author: | Michael Dale Payne [ Tue Nov 22, 2005 6:02 am ] |
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I use natural shell not ablam. I break to required length miter one end to fit perfect with the miter of the previous and miter the other end for the next piece to matched to. depending on the size and shape of the guitar there may be as many as 60-80 pieces each fitted to each other. as short as 3/16" long is waist and as long as 1/2" in straight areas. Even on big curves I keep length fairly short to avoid getting a faceted apearance. With out Teflon strips it would be a major pain to get the pieces fitted and glued up good and tight at the same time you purfed and binded. Many use ablam and that almost eliminates the need to match fit pieces. However I do not like ablam because if I have to sand the pattern can get pretty funky when sanded part way through a laminate layer. This is the reason I use natural shell. A good bit more work, but always natural looking patterns. |
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| Author: | Steve Kinnaird [ Tue Nov 22, 2005 6:20 am ] |
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Andy--you will find that this type of shell work is very forgiving. The first time I asked these questions, the fellow doing the work said, rather off-handedly, "Oh yes, the pearl is self-mitering". Huh? was all I could come up with. But he was / is right--sort of. If the curve isn't too severe, the break really does disappear when the CA glue floods in. When the curve starts to bend a bit more, I find that dressing the ends of the mating pieces helps the joint look clean and intentional. I keep a small file, an emory board, and a fingernail trimmer on hand when laying in the pearl. Your first job will convince you that it is far easier than it looks. Steve |
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| Author: | Andy Zimmerman [ Tue Nov 22, 2005 6:27 am ] |
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Thanks for all the advice |
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| Author: | Michael Dale Payne [ Tue Nov 22, 2005 7:31 am ] |
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Steve is right, this is not a hard process. With taking the time to fit each miter on natural shell, it may take me 2 hrs at most to do a top.I have a small grinding wheel I use to grind the miter so that goes quick. Kinda stinks a bit and I wear a resperator. I agree that with most breaks the seam diapears when when gled using ablam but with natural shell it is some times unpredictable if the shell will break clean through all layers. This is very true of Paua. That is why I miter each edge |
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| Author: | Lars Rasmussen [ Tue Nov 22, 2005 7:32 am ] |
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Thanks Andy for asking the queation, i am thinking on give this a shot on next guitar. Do you use the exact same dimension of the teflonstrip as the shell or is the slot oversized? |
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| Author: | Michael Dale Payne [ Tue Nov 22, 2005 7:39 am ] |
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Most shell purf is .063 wide .063 teflon  The teflon tends to be about .063-.065 as cut by most suppliers. I have had some tight spots but nothing that cause a problem.
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| Author: | arvey [ Tue Nov 22, 2005 9:24 am ] |
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I also use real shell and lay out the outline of the guitar with the shell cut and mitered before hand. Then I glue it all as one. I haven't had a problem doing this and only tried the teflon once as I said. But everything is shaped before I glue it together so I rarely have to break any pieces. You can buy it pre cut to the outline you want from some suppliers if you want to do it that way. |
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| Author: | BlueSpirit [ Tue Nov 22, 2005 11:47 am ] |
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Below is a picture of a rosette I just finished. I used a teflon strip and wbw & bwbw wood purflings. I had no problems except that when I went to put in the (Straight)Ablam pieces, breaking them as I went along, I had to be very careful not to break or tear the very thin maple strips thar were positioned next to the Ablam. Hope this helps. 
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