"Not" so good knot part 2.

[navycop]

I attempted to make another celtic knot. I had good 60 degree angles. Some of my fill material was a little off. I think that was because it wasn't square on the bottom or the glue dried before I inserted all the way. Another thing is the space between the "X" and the circle is off. I am pretty sure I drilled in the center... Sorry for the bad pictures. took them with my iphone..

 

[lyonsacc]

But - you are improving! I'm finishing me second segmented attempt. Far from perfect, but a heck of a lot better than the first try.

Dave

 

[PTownSubbie]

Mike,

If the "X" is not centered in the knot, the blank wasn't drilled centered. It might have started in the center but if you are off by a slight bit it will never line up centered inside the oval....

Work on what we talked about. Square blank. Round before drilling. Hopefully those things will help.

You will get there!

 

[navycop]

Mike,

If the "X" is not centered in the knot, the blank wasn't drilled centered. It might have started in the center but if you are off by a slight bit it will never line up centered inside the oval....

Work on what we talked about. Square blank. Round before drilling. Hopefully those things will help.

You will get there!

Thanks for your help the other day. Found out I can't turn it round. My toolrest gets in the way when I put my between centers on.

 

[skiprat]

Mike, the big issue with Celtic Cross' and actually for many other types of segmentation is the reference points for each cut made.
Traditionally, the most common way is to attempt to keep the blanks as perfectly square as possible so that each side that is used as a reference is as similar to the next as possible. So to make a 'cross' you have 4 different reference points plus the end of the blank. Then you add a 5th point by trying to drill exactly in the middle of your first 4 points.

With a little ingenuity you can make all your cuts from the same reference point.

Here are some old pics that show a little indexing gadget that I knocked up that is used on a compound ( x-y ) table.
The blanks all rotate about their centres.
The only difference between the crosses and the feathers, is the depth of the cut.

Of course it is perfectly possible to do very accurate cuts on a table saw and then drill down the middle, but it has to be absolutely spot on or it looks bad.

For me, doing it all from the middle is far easier. :wink:

 

[jttheclockman]

Hi Mike

I know sometimes too many ideas are put forth and things get confusing. People telling you to do this or that. Each person has their own way of doing things which is good. You can choose whatever way you like to try and also try different ways and maybe come up with your own method.

Now with that said. A couple things that all can agree on. I would say you found 60 degrees. Simple knots such as what you are attempting, I found it is best to always use square material to start with, the infill must match the kerf, make all cuts the same which means clamping the blank the same way in the same reference place all the way around the blank. I disagree about turning the blank before drilling because this can throw the center off if not placed on the center axis. If you use square stock to begin with and the fill is just right that blank should come out as square as you started. Now all cuts are dead center. Find the center ( I use corner to corner method ) I use an awl to mark center. I use the PSI blank holding chuck and a starter bit to start my hole. But before I use the bity I use the point of the live center to line up the blank to be drilled. Tighten clamp and turn the lathe on. Then put starter bit in and drill. Then change to appropriate bit. Insert tube, making sure tube is where I want the knot to line up. Then procede like any other pen.

You obviously learned from your mistatkes about the infill material and the gluing and all so keep trying. Good luck.