Circle cutting jig

[OCtoolguy]

9 hours ago, JimErn said:

Same thought I had, octagonal, shaped like the state, etc

Might be a lot easier to just buy precut BB circles from woodpeckers on amazon

https://www.amazon.com/Circle-Cutouts-Unfinished-Crafting-Circles/dp/B07FNYP24G/ref=sr_1_1_sspa?keywords=round+wood+blanks&qid=1555850310&s=gateway&sr=8-1-spons&psc=1

Of course then you don't get to make the jig, so I guess it is a toss up

You are missing the point here Jim. I have a lot of scraps that I want to make use of. And each basket that I make generates 16 more of them. I'm thinking that I can offer the basket and a matching set of coasters.

 

[kmmcrafts]

That wing cutter thing.... I don't know what brand or quality of one that I have but I'm not quite sure why I still have it around here... the thing I have makes a better piece of scrap metal than a tool... LOL

How big a hole you thinking Ray? guessing like 4" if you're doing coasters.. I have a large hole saw kit.. and I've used it without the center drill.. with or without the drill.. it doesn't leave all that smooth of an edge.. 

[JTTHECLOCKMAN]

Ray you evidently never used a holesaw. The bit can not have a spring behind it because it needs to be solid to even start the holesaw. So it can not be solid and then miraculously spring up into the mandrel. As Kevin said those cutters and even a holesaw does not make clean holes or discs. You would need to sand them so you are back to the other methods I suggested. Now you could loosen the setscrew and it may slide up into the mandrel enough to be out of the way. But then you have to reset for the next group. Sounds like a whole lot of trouble for some round discs.  Remember too you need a drill press that has no play in the quill and no runout to start with to even get close to a good disc.   

[OCtoolguy]

I give up. I've tried to explain. It would work. Makes no difference. I'm going to make the jig and use it. I'll end up with a whole bunch of 4" coasters that won't need much sanding. But, at some point I will also make a hole saw with a retractable center point. And, Who knows, I might get rich. Lol.

 

Oh, JT, I have a whole bunch of hole saws. Remember, I sold tools for a lot of years. I do know how to use everything I sold. If you can grasp the concept of an automatic center punch, it's not that much of a jump to what I'm talking about. No matter what, I know what I'm envisioning.

 

 

Edited April 22, 2019 by octoolguy

[Foxfold]

2 hours ago, octoolguy said:

I know what I'm envisioning.

Go Tiger. I for one would love to see what you make and what you make with it.

[JTTHECLOCKMAN]

9 hours ago, octoolguy said:

I give up. I've tried to explain. It would work. Makes no difference. I'm going to make the jig and use it. I'll end up with a whole bunch of 4" coasters that won't need much sanding. But, at some point I will also make a hole saw with a retractable center point. And, Who knows, I might get rich. Lol.

 

Oh, JT, I have a whole bunch of hole saws. Remember, I sold tools for a lot of years. I do know how to use everything I sold. If you can grasp the concept of an automatic center punch, it's not that much of a jump to what I'm talking about. No matter what, I know what I'm envisioning.

 

 

Ray I wish you luck in this concept. But I would think it would have been invented by now if possible. Those center punches use a spring loaded action to make a dent not drill a hole. You got me on this one and I can be of no more help. What ever you make do post some photos. 

[OCtoolguy]

1 hour ago, JTTHECLOCKMAN said:

Ray I wish you luck in this concept. But I would think it would have been invented by now if possible. Those center punches use a spring loaded action to make a dent not drill a hole. You got me on this one and I can be of no more help. What ever you make do post some photos. 

JT, I don't want a hole. That's the "point". Pardon the pun. The retractable point would be just the keep the hole saw on center so that you would end up with a round piece of whatever material you were cutting without a hole in the center. In my mind, I can see it working. 

 

[kmmcrafts]

36 minutes ago, octoolguy said:

JT, I don't want a hole. That's the "point". Pardon the pun. The retractable point would be just the keep the hole saw on center so that you would end up with a round piece of whatever material you were cutting without a hole in the center. In my mind, I can see it working. 

 

Well... after this post I think I'm finally understanding what your trying to work with.. and I do see it maybe working.. I do believe you'll need a dimple in the material to be drilled though otherwise you're not going to be able to keep that retractable center piece on center.. 

[JTTHECLOCKMAN]

52 minutes ago, kmmcrafts said:

Well... after this post I think I'm finally understanding what your trying to work with.. and I do see it maybe working.. I do believe you'll need a dimple in the material to be drilled though otherwise you're not going to be able to keep that retractable center piece on center.. 

Better man than I

 

There are so many versions of circle cutting jigs out there and can be found on google. I have an older version I bought many years ago and believe it was Woodcraft and it used a pin as the pivot point for a bandsaw but could be adapted for use with router, jigsaw, scrollsaw. I made a larger one from plywood because I was making ship wheel clocks and cutting the circles on a bandsaw. I sold the pattern to Steebar back in the day. Need to look for the pattern.or photo. 

 

https://steebar.com/search.php?search_query=ships+wheel+clock

Boy I look back through some of those plans, I can not believe they still carry many of them. Brings back alot of memories. I remember making those Pyramid clocks and trying to figure out the correct compound angles I have not made many of those projects in years. trip down memory lane.

https://steebar.com/pyramid-clock-plan/ 

This desk set still had my old business card on it.

https://steebar.com/clock-plans/?sort=featured&page=1

Edited April 22, 2019 by JTTHECLOCKMAN

[OCtoolguy]

1 hour ago, JTTHECLOCKMAN said:

Better man than I

 

There are so many versions of circle cutting jigs out there and can be found on google. I have an older version I bought many years ago and believe it was Woodcraft and it used a pin as the pivot point for a bandsaw but could be adapted for use with router, jigsaw, scrollsaw. I made a larger one from plywood because I was making ship wheel clocks and cutting the circles on a bandsaw. I sold the pattern to Steebar back in the day. Need to look for the pattern.or photo. 

 

https://steebar.com/search.php?search_query=ships+wheel+clock

Very nice JT. I love that ship's wheel. Thanks for the tip.

 

[OCtoolguy]

1 hour ago, kmmcrafts said:

Well... after this post I think I'm finally understanding what your trying to work with.. and I do see it maybe working.. I do believe you'll need a dimple in the material to be drilled though otherwise you're not going to be able to keep that retractable center piece on center.. 

You are correct. But, I think the "dimple" would be easier to deal with than a hole. Thanks for your support Kevin. I'm glad that you get it.

 

[JTTHECLOCKMAN]

5 minutes ago, octoolguy said:

You are correct. But, I think the "dimple" would be easier to deal with than a hole. Thanks for your support Kevin. I'm glad that you get it.

 

He just said that. He doesn't get it.

[kmmcrafts]

1 hour ago, JTTHECLOCKMAN said:

He just said that. He doesn't get it.

Get what? 

 

[Lucky2]

Ray, if you would do as John(JT) has suggested, you would end up with no more then a dimple in the center of the disc. Al you would need to do, is have the piece of wood your jig is made out of, to be thick enough for the nail to be held firmly into place. Now what I'm thinking of is for scroll saw use only, but the jig could be made very much like the ones used on a drill press. I hope that this explanation will work, and that it's not to long to read. 

But if you were to take the piece of wood, you plan to use as a base. And you cut a kerf into it, so that it could be moved farther from or closer to the blade. Then add stoppers to the underside, so that it can't move any from side to side. Then with it still in place, mark a line that runs 90* from the front of the blade to the right or left. I prefer the right hand side, but you choose. Now, remove the base, which should be no less then 5/8th" plywood or mdf I prefer 3/4"plywood. Do not use OSB or Particle board, they are not strong enough. These holes have to be very close to the size of the nail, so that there is no movement in any direction. But, they also can't be so tight, that they cannot be easily removed. I'd suggest a 2 1/2" nail be used as your pin, you cut it off so that no more then 3/32" is up through the drilled hole. You will have to sharpen the tip of the cut-off nail to a point. And you should also drill the underside of the base, with a bit just large enough for the top of the nail to sit into. Doing so, will help hold the nail in place better. This should work, but you will only be able to cut circles that are within 3/8" to a 1/2" larger or smaller then the other. It would depend on how far apart you drilled the holes. Now, if you were good at using a router, there's an adjustable one that you could make. It would be almost the same, as the ones used on a bandsaw and adjustable to any size as well. There's numerous ways of making one of these, and they're not that hard to make. You could make an adjustable one, just using a tablesaw. This is something that I never imagined would be requested for scroll saw use, but to each their own. But, I suppose one could come in handy, if you had a lot of circles to cut. I make no guarantees that this will work, I just came up with this idea after reading the posting.

 

Len

[Smudger]

I made one a year or two back, I think I posted about it at the time, I use spiral blades for it as normal blades still wandered a little bit.

 

[rjweb]

May I make a suggestion Ray, don’t do circles make the coasters square, RJ 

[teachnlearn]

This is getting surreal, 40 replies on cutting a circle. If you use a 50 cal gun. Which has a bullet size of 1/2 inch and shoot it 12 times into plywood, you will get a 6-inch circle. If there are things behind it you get the bonus of them getting a 6-inch circle too. RJF

Edited April 23, 2019 by teachnlearn
spelling

[OCtoolguy]

27 minutes ago, rjweb said:

May I make a suggestion Ray, don’t do circles make the coasters square, RJ 

That's no fun. But, I will take that into consideration.

 

[OCtoolguy]

8 minutes ago, teachnlearn said:

This is getting surreal. If you use a 50 cal gun. Which has a bullet size of 1/2 inch and shoot it 12 times into plywood, you will get a 6-inch circle. RJF

I have a .45 so I will have to do the math.

 

[teachnlearn]

9 minutes ago, octoolguy said:

I have a .45 so I will have to do the math.

 

A 45 cal guns bullet is .45 inches. For a 6 inch circle, you're going to have to fire it 13..333333.......... times. I did mathematics for a living, now I stare at computer screens just waiting for that question! RJF

Edited April 23, 2019 by teachnlearn

[OCtoolguy]

3 minutes ago, teachnlearn said:

A 45 cal guns bullet is .45 inches. For a 6 inch circle, you're going to have to fire it 13..333333.......... times. I did mathematics for a living, not I stare at computer screens just waiting for that question! RJF

Now all I have to do is load .333333 bullets. 

 

[teachnlearn]

2 minutes ago, octoolguy said:

Now all I have to do is load .333333 bullets. 

 

You have a scroll saw. Use a pattern and cut it down. Just go to the patter request forum with a picture of your bullet and ask them to create a .333333 pattern. RJF

Edited April 23, 2019 by teachnlearn

[OCtoolguy]

4 minutes ago, teachnlearn said:

You have a scroll saw. Use a pattern and cut it down. Just go to the patter request forum with a picture of your bullet and ask them to create a .333333 pattern. RJF

Would that be by weight or diameter? All of my wadcutters are 185 grain. So I guess I need something in the area of 61.67 grains. Now all I have to do is figure out the diameter.

 

[kmmcrafts]

45 minutes ago, octoolguy said:

Now all I have to do is load .333333 bullets. 

 

That will be quite tricky.. LOL

[JimErn]

9 hours ago, teachnlearn said:

This is getting surreal, 40 replies on cutting a circle. If you use a 50 cal gun. Which has a bullet size of 1/2 inch and shoot it 12 times into plywood, you will get a 6-inch circle. If there are things behind it you get the bonus of them getting a 6-inch circle too. RJF

I will grant you that Geometry was a long time ago, and my memory might not be up to snuff, but

as I remember a 6" coaster would mean a 3" radius, and the formula, C = 2πr would mean that the distance around the circle is 18.85 inches

12 shots around the circumference is not going to make it with a 50 cal.

Then there is the issue that if you had pinpoint aim and the center of the 50 cal bullet hit the line, the remaining part would be smaller than a 6" circle, so the radius for the aim point would have to be 0.25" larger, and thus a larger circumference requiring yet more bullets.