Segmented glueing problem

[Ben Richardson]

I am having trouble joining the two half rings togather. I have a 12" disk sander that I have been using to do the final sanding to make any error go a way, but it seams the it is not making the joints perfictly flat to each other. Anyone have any thoughts on what I am doing wrong?

[Richard Madison]

Ben,
Could be any of several small things. Try very gentle sanding with the disc sander, followed by a few strokes on a sheet of 80 or 100 paper taped to a flat surface like a table saw table. Any chance you could post a picture? Match one joint and show us the other one.

[Bill Wyko]

I now have gone to using a 6x48 belt sander. Have you held a straight edge to your disc?

[Robert McGowen]

The table on your sander is probably not at exactly 90 degrees to the disc. If you sand both halves on the same side and push them together, any error will be doubled and easily seen. Try this (assuming you are not doing this already) Put the two halves together. Pick up one half and flatten the ends. Take the second half and flip it over and flatten the ends. Flip it back over and put it with the second half. Doing it this way ensures that any variances in your sanding table will cancel each other out. One half may be 89.5 degrees but the other half will now be 90.5 degrees, so they will fit perfectly.

[Richard Madison]

Would like to convert my 6x48 to EVS to slow it down, but too much $$. No room to change pulley sizes. Can run the 15-1/2" disc sander at 50 rpm when needed. Good for fixing a joint without overdoing it.

Robert, How do you get both sides of half rings flat? Mine always have squeeze out on "top" side.

[Malcolm Tibbetts]

Ben, if I understand correctly, you are having trouble creating a perfect miter fit between the two halves. Using only a disc sander to true up the glue surfaces can sometimes be difficult because the rate of travel towards the outside of the disc is faster than the center area of the disc. This results in more aggressive sanding action towards the outside of your joints and is usually visible in the form of light coming through the joint when you dry fit and put it up to a bright light. Careful, slow sanding will help, but it doesn't always work. I use a very simple sanding jig to perfect the joints. Instead of placing the half rings vertically on flat sandpaper, I place them flat, horizontally on a piece of MDF. Attached to the MDF is about a 2" high hardwood fence with 80-grit paper adhered. Rubbing the half rings back and forth a few times will usually, very quickly produce a perfect fit. Don't forget to place one half ring upside-down so that any error in the 90-degree fence will be cancelled. Keeping the discs flat is a lot easier than rubbing them vertically with only hand support. Good luck.

[Travis R. Nelson]

I am having trouble joining the two half rings togather. I have a 12" disk sander that I have been using to do the final sanding to make any error go a way, but it seams the it is not making the joints perfictly flat to each other. Anyone have any thoughts on what I am doing wrong?

First thing I would do is reset the miter sled. Accurate rings start on the saw. I use a simple horizontal hand sanding jig similar to what others have mentioned. Just a couple of light, slow and steady passes to perfectly fit halves. Good luck and remember to have fun in the shop it is a hobby not a job!!

[Larry Marley]

Yep,
What Malcolm said....

[Ben Richardson]

Thanks,
I think that is what is happening. One question why sand with the sanding board vertical instead of horizontal?

[Malcolm Tibbetts]

Thanks,
I think that is what is happening. One question why sand with the sanding board vertical instead of horizontal?

Ben, it doesn't make any difference if you sand with the half-ring vertical or horizontal. The point is, if you use a jig instead of just balancing a half-ring on a piece of flat sandpaper, then you'll have an easier time keeping the ring perpendicular to the sandpaper.

[Larry Edgerton]

I make inlay strips once in a while and one of the best ways I have found is 3M stickit paper firmly stuck on the tablesaw, and I use the Beismeyer fence to hold it verticle as I slide the piece lightly back and forth on the paper. I do the other side flipped the other way to make up for any tiny bit out of square to the table that the fence may be.

This should work for you and is very controlable. I screw up too many things with the disk, so when it gets close I prefer by hand.

Hope this helps......