Making a four sided frame is pretty easy, just cut all the pieces at 90 degrees, but what if you wanted to make a 12-sided frame? What angle do you cut the pieces? This isn’t a hypothetical question if you are a woodturner; making segmented bowls requires you to glue together many multi-segmented “frames” into a larger bowl blank.
Making the multi-segmented frames requires calculating the right miter angle and setting up your table saw’s miter gauge precisely so there are no gaps the miters. If there are gaps in the miters, there will be gaps in the finished bowl. Tools like the new Rockler perfect miter setup blocks make it easy to properly align a miter gauge to cut the correct miter angles for frames from 4 to 12 sides with no calculations or measurements needed.
The hexagonal blocks fit over any 3/4″ wide miter bar and are made from reinforced plastic. There are three different blocks in the set:
- 4, 5, and 6-sided frame setup block
- 7, 8, and 9-sided frame setup block
- 10, 11, and 12-sided frame setup block
To use the blocks, select the block and edge with the number of sides you need. Fit the block onto the miter bar. Rotate the fence and slide the block back until the edge and fence are parallel and have no gaps between them. Lock the miter gauge, it is now set to the precise angle you need.
You get the three different miter setup blocks for $40.
Above is an example of a segmented bowl in case you didn’t know what one was.
Before the Rockler perfect miter setup blocks, I only knew of one other tool aligning your miter gauge to make ring segments: the MiterSet.
Rather than dedicated permanent gauges, the miter set uses a miter slot, two pins, and several carefully positioned holes, to perfectly align your miter gauge.
To use it you put your miter gauge in the slot, set one pin in the “double-aught” hole and the other in the hole with the number of sides you wish. Then you turn the head of the miter gauge until it lays flat against both pins. The gauge is double-sided so you can set the correct angle no mater which side of the blade you use the miter gauge.
The difference between the two different systems is that the Rockler perfect miter setup blocks are simpler to use and less expensive, while the MiterSet is more versatile.
I’ve only made a few ring segments for a failed segmented bowl, but getting the miter gauge on my table saw set to the right angle took quite a bit of worrying to get the joints perfectly tight. I’m not sure if I ever will attempt one again, but knowing the time investment involved in making a segmented bowl, I’d probably spend $40 for the Rockler setup blocks in a heartbeat to make it go easier.
A bit like the Veritas Poly-gauge:
I forgot about the Poly-gauge.
It operates differently. It aligns the saw blade and the miter gauge, rather than just the miter gauge. It might even work on a miter saw.
Unless they can take the slop out of the fact that no miter gauge has a bar that is exactly .750” and few table saws have an accurate slot either, I just don’t see it being a needed item. This appears an easy item to make on a 3D printer since ultimate accuracy isn’t attainable regardless who makes it.
A CNC might be even better. More and more people have them. Even the $250 ones are fun for basic (and small) wood and plastic projects.
They do make “perfect fit” miter gauge bars that can be adjusted by tightening screws. Maybe that could improve the accuracy?
neat idea. I think I like the poly gage better but rockler does try to make things easy.
OH and who doesn’t run their table saw mitre gage without a sacrifical piece of 3/4″?
(meant as a joke y’all)
Any woodworker who is making and has the skills to repeatedly and accurately assemble a 7, 9, 11 sided polygon does not need this gauge to set the miter gauge on their table saw.
Unfortunately the poly gage is no longer available according to the website.
The Rockler? I see it as in-stock and available for purchase.
No he means the Veritas Poly-Gauge fred linked to in the first comment.
It is unfortunate, but understandable. This is kind of a niche product.
What is the website to get the length of the segments for cutting the segments