His and Hers Half Celtic Knot

[Fine Engineer]

Black Walnut and Maple, Designer kits.
Sorry for the crap image, I didn't think to get a good picture until I was ready to ship these.

 

[magpens]

@Fine Engineer

Jeff, can you link me to a "how-to" for a Half-Celtic, please.

I am having some conceptual difficulty trying to figure out how to do it, and I think I would like to try. . .

I've never done a Full-Celtic, and for some reason it has never interested me that much, but I like the Half-Celtic.

 

[mark james]

Very nice.

 

[jttheclockman]

Interesting. They remind me alot of scallops when that was real big here.

 

[jrista]

Very nice. I think I like a half-celtic vs. the full. Seems more symmetrical around the pen, maybe... Curious how you actually do that...I guess you have to cut a notch just to the right point, then slide in the other material?

 

[Alan Morrison]

Lynn Lacey has a youtube video on how to make this design which he calls 'Snake Eyes'.

 

[Kcimdrib]

Nice Pena love that design

 

[Fine Engineer]

@Fine Engineer

Jeff, can you link me to a "how-to" for a Half-Celtic, please.

I am having some conceptual difficulty trying to figure out how to do it, and I think I would like to try. . .

I've never done a Full-Celtic, and for some reason it has never interested me that much, but I like the Half-Celtic.

The name says it all; half knot. Instead of cutting all or nearly all the way through the blank, you set up a stop to cut exactly half way through. Other than that, it is the same process of gluing in an insert, sand it down flush with the rest of the blank once dry, turn 90° and do it again. What I did was cut these on the band saw, make the first cut, turn 180° and make the second cut. I then adjusted the stop such that the second cut overlapped the first cut such that the second cut ended right at the far face of the kerf of the first cut. This also trims the first insert when making the opposite cut such that the second insert then makes a tight fit to the previous one.

This is kind of the same process I used for the previous segmented pens with the thin metal separator, except with those, I make the first cut, rotate 180° and make the second cut, which then separates the blank. With those, I insert the metal, glue and clamp, then turn 90° and do a complete cut again, and glue with the added metal.

What you need to be careful about is that at the interim stages, this is very weak and can come apart. The nice thing is that they are al flat surfaces so can be pretty easily glued back together. The thing to watch for (and you can see this error in the walnut pen) is seating the second insert completely so that it makes a tight connection with the insert that is 180° apart. If you miss, it shows as a gap.

Does this give enough insight to duplicate this?

Jeff

 

[Fine Engineer]

Lynn Lacey has a youtube video on how to make this design which he calls 'Snake Eyes'.

Thanks for noting this. Here's the link to Lynn's method.

This is similar in concept, but I am using a band saw with a cutting fixture where he uses a scroll saw and does it by hand.

Jeff

 

[magpens]

@Fine Engineer

THANK YOU, Jeff ! !
Yes, your description of the process makes perfect sense . . I'll make up a jig to get the positions and depths of the cuts correct.
And I appreciate the importance of seating the inserts so as to make a tight butt connection/joint.

Strange as it may seem, just as I noticed that you came online a few moments ago, I got a "revelation" of the process !
And it was almost exactly as you worded your description !
Talk about "tele-communication" ! !

I think it will be important to start with an accurately square blank cross-section.

Thanks again !

 

[jrista]

Thanks for noting this. Here's the link to Lynn's method.

This is similar in concept, but I am using a band saw with a cutting fixture where he uses a scroll saw and does it by hand.

Jeff

Good video. I really like the simplicity yet beauty of just using a metal.

One question...his second cuts appear to have resulted in misalignment of the first cuts, and you can see how the first layer of aluminum doesn't line up. I suspect that is because the kerf of this scrollsaw blade was wider than the metal used... Is there any way to avoid that problem when using thin metals? Or for that matter, any kind of thin segmenting material? I have a bandsaw, which is probably what I would use to do such a thing. I believe my current blade has a 0.02" kerf, so I imagine that would be at the very least the thinnest material I could use to avoid the misalignment issue (maybe slightly wider, cuts always seem to be a little wider than the rated kerf of the blade, not sure why).

 

[Fine Engineer]

Good video. I really like the simplicity yet beauty of just using a metal.

One question...his second cuts appear to have resulted in misalignment of the first cuts, and you can see how the first layer of aluminum doesn't line up. I suspect that is because the kerf of this scrollsaw blade was wider than the metal used... Is there any way to avoid that problem when using thin metals? Or for that matter, any kind of thin segmenting material? I have a bandsaw, which is probably what I would use to do such a thing. I believe my current blade has a 0.02" kerf, so I imagine that would be at the very least the thinnest material I could use to avoid the misalignment issue (maybe slightly wider, cuts always seem to be a little wider than the rated kerf of the blade, not sure why).

For the first cut, the kerf doesn't really matter. But for the second it does. What I did on one of the latest blanks, is make a shim that is the thickness of the saw kerf, and use that on the end stop when making the second pair of cuts. This should correct the alignment for the second 'v'. To really make this line up, both cuts need to be precise, and the hole for the tube needs to be dead centered. So far mine have been close enough to be attractive, but not as exact as I want, so I'm still working on this as well.

Jeff

 

[Fine Engineer]

@Fine Engineer

THANK YOU, Jeff ! !
Yes, your description of the process makes perfect sense . . I'll make up a jig to get the positions and depths of the cuts correct.
And I appreciate the importance of seating the inserts so as to make a tight butt connection/joint.

Strange as it may seem, just as I noticed that you came online a few moments ago, I got a "revelation" of the process !
And it was almost exactly as you worded your description !
Talk about "tele-communication" ! !

I think it will be important to start with an accurately square blank cross-section.

Thanks again !

It isn't hard to get this to work, it is hard though, to get it to work perfectly. To get all the lines to align perfectly, the blank needs to be exactly square, the fixture needs to be precise, and the hole needs to be dead centered and straight. I'm still working on getting a perfect match of both 'v' inlays. The engineer in me just isn't content with approximations

 

[jrista]

For the first cut, the kerf doesn't really matter. But for the second it does. What I did on one of the latest blanks, is make a shim that is the thickness of the saw kerf, and use that on the end stop when making the second pair of cuts. This should correct the alignment for the second 'v'. To really make this line up, both cuts need to be precise, and the hole for the tube needs to be dead centered. So far mine have been close enough to be attractive, but not as exact as I want, so I'm still working on this as well.

Jeff

I think even for the first cut, it would matter if the material being used is much thinner than the blade's kerf, right?

I see that some people account for this, and will purposely and very carefully align their second cuts to make sure that the resulting mis-alignment of the first layer of metal aligns nicely within the second. But I often see the misalignment is random and haphazard.

I am guessing that for any material thinner than (or, for that matter, thicker than) the blade's kerf, you would have an alignment problem...but as long as you use material that is the same thickness as the kerf then everything should align fine...

 

[Fine Engineer]

I think even for the first cut, it would matter if the material being used is much thinner than the blade's kerf, right?

I see that some people account for this, and will purposely and very carefully align their second cuts to make sure that the resulting mis-alignment of the first layer of metal aligns nicely within the second. But I often see the misalignment is random and haphazard.

I am guessing that for any material thinner than (or, for that matter, thicker than) the blade's kerf, you would have an alignment problem...but as long as you use material that is the same thickness as the kerf then everything should align fine...

It's not so much about allowing for the kerf, but the precision of both cuts and the accuracy of the tube hole. All of those things conspire to make the pattern more random.