Apollo1617
Member
I'm brand new here. I've made 3 bowls so far. I notice that the ring glue joints seem to get darker. Especially with Maple. Is it me?
Dark Glue Lines
- Thread starter Apollo1617
- Start date
Ken Sherwin
PRO Member
What glue are you using?
How are you flattening your rings so that they will fit tightly together?
How are you flattening your rings so that they will fit tightly together?
Glue.
Titebond translucent dries clear.
Titebond original I have used with good results. though glue lines can darken over time.
Some in my club use Elmers white all purpose glue. it dries clear.
If you are seeing a noticeable glue line between your rings.
- rings may not be perfectly flat
(I tend to use a large sanding block with 80 grit, will mark the top of the ring with a pencil, turn the lathe on at a low speed and sand the ring till the pencil marks are gone. Check for flatness with a good straight edge. Using a flashlight and the straight edge on the ring shine the light up from the down side. If you see no light coming through the ring should be flat and ready for the next ring to be glued on.
Making a segmented bowl takes time and patience.
Check to make sure your rings are flat before gluing.
I remember reading in a segment book about if the pieces don't fit correctly before gluing, gluing will not make them fit right.
Titebond translucent dries clear.
Titebond original I have used with good results. though glue lines can darken over time.
Some in my club use Elmers white all purpose glue. it dries clear.
If you are seeing a noticeable glue line between your rings.
- rings may not be perfectly flat
(I tend to use a large sanding block with 80 grit, will mark the top of the ring with a pencil, turn the lathe on at a low speed and sand the ring till the pencil marks are gone. Check for flatness with a good straight edge. Using a flashlight and the straight edge on the ring shine the light up from the down side. If you see no light coming through the ring should be flat and ready for the next ring to be glued on.
Making a segmented bowl takes time and patience.
Check to make sure your rings are flat before gluing.
I remember reading in a segment book about if the pieces don't fit correctly before gluing, gluing will not make them fit right.
Ken Sherwin
PRO Member
I was unable to sand rings dead flat consistently with a sanding block on the lathe. I kept making slight cones where the outer part of the ring sanded away more than the inner part. The technique works but I had to pay attention and check my work on every single face. Another way to check flatness is to lay a hopefully finished ring on the lathe bed and see if you can detect any rocking when you press on opposite sides of the ring. A really flat ring won't rock at all, no matter where or how hard you push.
What really works for me is a 12" sanding disk on a live center in a 12" tailstock on my 16" lathe. Yes it feels as wrong as it looks! A full turn on the tailstock only moves the quill 0.080" and the sanding disk gets held dead square to the ring. No more cones for me. Yay! This effectively makes the lathe a random orbit sander with a 4" orbit. To finish a ring, I stop cranking the quill and let it "spark out". You can hear and feel the difference when the paper is done cutting.
What really works for me is a 12" sanding disk on a live center in a 12" tailstock on my 16" lathe. Yes it feels as wrong as it looks! A full turn on the tailstock only moves the quill 0.080" and the sanding disk gets held dead square to the ring. No more cones for me. Yay! This effectively makes the lathe a random orbit sander with a 4" orbit. To finish a ring, I stop cranking the quill and let it "spark out". You can hear and feel the difference when the paper is done cutting.
Attachments
Last edited:
Apollo1617
Member
I'm using Titebond 3 Ultimate
Apollo1617
Member
I run the rings thru a drum sander prior to glue up.
Ken Sherwin
PRO Member
I've found that Titebond 3 turns dark brown when cured.
Ken Sherwin
PRO Member
I gave up using my drum sander to flatten rings because it was too springy. Soft spots in the grain or less wood under the drum at one time made the drum dig in a little bit, leaving a gap. Lightly rub a sanded ring face with a pencil then rub that face on a sheet of 150 or 180 grit sandpaper glued to something flat like MDF or a L\laminated sink cutout. Check that ring face often. If the ring is flat, you should see the pencil marks fade away evenly. When I did that, the pencil marks faded into lighter and darker stripes parallel to the sanding drum axis.
Apollo1617
Member
Would rings flatten when you pressed them together if it was slightly warped???? Maybe my drum sander is off. I'll try the pencil thing on a large piece of Pine & see how it comes out.
Does using hose clamps warp the ring?? I'm sure there are posts on here about it. I'll do some looking.
What is the alterative?? (and I just bought a gallon of Tightbond III.) Somehow, a segment that I glued in a ring was a tad higher that the rest in the ring. It created a gap that filled with glue.?? I read in one of the forums here, " I don't do this because it's easy, I do it because it's hard"
imo, there is a chance that gluing a warped ring to a non warped ring will warp both rings.
I have glued a slightly warped 1/8 inch ring to a 3/4 inch ring and the result was a flat combined ring.
it can if you tighten the clamp to much.
I have used Titebond Original and Titebond translucent.
Some club member use Elmers white wood glue.
Ken Sherwin
PRO Member
1) You really need to test the flattening ability of your drum sander on a segmented ring of a wood you want to use. If your sander is springy like mine was, it will produce uniform results if the board you stick in it is uniform. Rings are not uniform. There is minimal wood under the drum at the beginning and end of the pass that effectively produces snipe. There is maximum wood under the drum just before the hole in the middle of the ring goes under the drum, minimal wood as the drum crosses the center of the ring where you only have 2 sections of wood that are as wide as the wall thickness, then maximum wood again where the hole in the ring comes out from under the drum. By the way, sanding pine is an excellent way to clog your drum's paper with pine resin and destroy it's ability to sand evenly. It will leave grooves in that ring you try to flatten next that are perpendicular to the drum. I found this out after my son flattened a pine tabletop he was working on.
2) A ring would flatten when clamped only if the ring height is so short that you can noticeably bend it with your fingers. If you have to clamp a lot to close a joint, that joint is likely to fail later, just like with flat work. Glue is a really bad crack filler. This is why you want those surfaces dead flat before you apply glue.
3) A hose clamp should only cause a freshly glued ring to dish if the ends of the segments are not 90 degrees to the ring face and the segments are not alternated properly to cancel that out-of-squareness. That said, once you face that ring with your bowl gouge then sand the face, that cone-shaped dish will be gone and the ring will be flat.
4) A segment that sticks up when the glue is dry is no problem because it will get cleaned up when you face and sand the ring.
5) To use up that gallon of TB3, switch to walnut or other very dark wood or use it on outdoor furniture where a dark joint doesn't matter but having waterproof glue does. I use TB Original, even in maple and basswood, but I make an extreme effort to have minimal (I try for negligible) glue lines.
6) A fun exercise is to tilt the saw blade 10 or 15 degrees then mark and cut a ringful of segments. Study how the segments do or don't fit together to make a perfect ring.
2) A ring would flatten when clamped only if the ring height is so short that you can noticeably bend it with your fingers. If you have to clamp a lot to close a joint, that joint is likely to fail later, just like with flat work. Glue is a really bad crack filler. This is why you want those surfaces dead flat before you apply glue.
3) A hose clamp should only cause a freshly glued ring to dish if the ends of the segments are not 90 degrees to the ring face and the segments are not alternated properly to cancel that out-of-squareness. That said, once you face that ring with your bowl gouge then sand the face, that cone-shaped dish will be gone and the ring will be flat.
4) A segment that sticks up when the glue is dry is no problem because it will get cleaned up when you face and sand the ring.
5) To use up that gallon of TB3, switch to walnut or other very dark wood or use it on outdoor furniture where a dark joint doesn't matter but having waterproof glue does. I use TB Original, even in maple and basswood, but I make an extreme effort to have minimal (I try for negligible) glue lines.
6) A fun exercise is to tilt the saw blade 10 or 15 degrees then mark and cut a ringful of segments. Study how the segments do or don't fit together to make a perfect ring.
Apollo1617
Member
I ran a piece of Birch plywood as wide as my feed table that I penciled, thru & it came out perfect. I ran a 9" glued up 1/2" ring thru, ( both sides) and it's as flat as possible.
Looking at the photo I'm including, it appears that the segment on the left is shorter than the one on the right, creating a gap for glue. Not sure how that's possible since I sanded it flat.
Pictures not that clear but right in the center you can see the dark glue line disappear. If you look close, the segment on it's right is thicker.
Looking at the photo I'm including, it appears that the segment on the left is shorter than the one on the right, creating a gap for glue. Not sure how that's possible since I sanded it flat.
Pictures not that clear but right in the center you can see the dark glue line disappear. If you look close, the segment on it's right is thicker.
Attachments
Not sure what caused your glue line with since you say the ring was sanded flat..
- The ring was not flat in that area. Check to make sure the ring is flat before gluing
Looking at the image you posted there is are other glue lines that can be seen. Zooming in it is not clear if it is just glue that could be sanded out.
I would change glue to something other than Titebond III. Titebond orginal, Titebond translucent, Elmers white Wood glue are glues that have been used in building segmented vessels.
- The ring was not flat in that area. Check to make sure the ring is flat before gluing
Looking at the image you posted there is are other glue lines that can be seen. Zooming in it is not clear if it is just glue that could be sanded out.
I would change glue to something other than Titebond III. Titebond orginal, Titebond translucent, Elmers white Wood glue are glues that have been used in building segmented vessels.
Apollo1617
Member
Maybe I only did one side of the ring
. I'm old.
. I'm old.
Ken Sherwin
PRO Member
You have a segment lower than others so it's not flat in that area. You're not done flattening yet. You're only done when every point on the face is exactly level with every other point.
I've had rings that glue up with segment heights that vary by a quarter of an inch because I was reusing some material but when I turn then sand that face, that face is completely flat.
I've had rings that glue up with segment heights that vary by a quarter of an inch because I was reusing some material but when I turn then sand that face, that face is completely flat.
Doug Drury
PRO Member
Titebond III and Titebond II will both turn brown and leave noticeable glue lines in lighter colored woods such as maple. The only advantage to using TB II or TB III is resistance to moisture. TB II is water resistant, TB III is water proof (to a degree). Most segmented pieces are not exposed to water or moisture, so Titebond original is the preferred glue by most.
My best practice is to make sure all rings fit BEFORE applying any glue. This starts at the gluing of segments to make a ring (do a dry fit before gluing up). If the dry fit is good, you'd have to crank down on a band clamp excessively to warp the ring. You really only need enough pressure to hold everything in place until the glue grabs (10-50 LBS pressure). Once the rings have been made, once face needs to be flat (the glue face) before they are the rings are glued together. A drum sander will take you most of the way, but not all the way. The drum sander will make the entire ring the same thickness (top and bottom sides parallel), but does not guarantee that the ring is flat. The ring being glued onto the stack should be flattened on one side by sanding on a flat surface after it has come through the drum sander. The last ring glued (or your base plate when starting) should be trued up on the lathe and then sanded. A straight sanding block (stick, piece of plywood, whatever you want to use that is flat) should span both sides of the ring. This will stop you from making a conical shape. Use pencil lines so you know when you're flat.
My best practice is to make sure all rings fit BEFORE applying any glue. This starts at the gluing of segments to make a ring (do a dry fit before gluing up). If the dry fit is good, you'd have to crank down on a band clamp excessively to warp the ring. You really only need enough pressure to hold everything in place until the glue grabs (10-50 LBS pressure). Once the rings have been made, once face needs to be flat (the glue face) before they are the rings are glued together. A drum sander will take you most of the way, but not all the way. The drum sander will make the entire ring the same thickness (top and bottom sides parallel), but does not guarantee that the ring is flat. The ring being glued onto the stack should be flattened on one side by sanding on a flat surface after it has come through the drum sander. The last ring glued (or your base plate when starting) should be trued up on the lathe and then sanded. A straight sanding block (stick, piece of plywood, whatever you want to use that is flat) should span both sides of the ring. This will stop you from making a conical shape. Use pencil lines so you know when you're flat.
Ken Sherwin
PRO Member
With light colored wood, the only way to eliminate all visible glue lines is to eliminate dark glue. The way to eliminate uneven glue lines is to eliminate uneven gaps in the wood. Light colored or transparent glue makes the gap problem less visible until you stain the project like I did in the pic to the left. I scrapped the first try at that project because glue lines showed up while staining. That and the open segments in the neck were what we euphemistically call "learning experiences".
Wayne Miller
PRO Member
You should have the piece centered on the Cole jaws and the sanding disc is in an odd position. I suggest that you start with the turning on a glue block. that way you will always be centered. I use a small sanding block and I gently pus against it with something mounted on the tailstock. The something depends upon the size of the ring to be flattened.