# Circle cutting jig?



## Muzzy17is (Sep 14, 2014)

I'm going to be cutting a bunch of circles out of 3/4 - 5/8 in thick hazard woods of various types around 3 1/2 in foam. 
Do you think it would be more efficient to use a band saw or a router with a circle jig set up on either one. Once I get rolling I'll be cutting these on a reg basis.


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## Masterjer (Nov 6, 2012)

I vote for a circle cutting jig in the band saw.


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## epicfail48 (Mar 27, 2014)

Personally I'd go for the route, but I don't think youd see a huge differenc either way. The router is imagine would leave a slightly cleaner edge, but its probably a wash


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## TimPa (Jan 27, 2010)

much depends on the end needs. if you need a clean edge - the router will provide the cleanest. we use a 1/2" spiral carbide and you almost don't need to sand it. but we band saw (by hand) the waste away first to ease up on the routing process - so two steps required. 

a band saw will be faster, but leave a ougher edge.

size matter too. routing a small circle get a little tricky.


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## FrankC (Aug 24, 2012)

"I'm going to be cutting a bunch of circles out of 3/4 - 5/8 in thick hazard woods of various types around 3 1/2 in foam."

Am I the only one that does not understand the above sentence?


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## difalkner (Nov 27, 2011)

FrankC said:


> "I'm going to be cutting a bunch of circles out of 3/4 - 5/8 in thick hazard woods of various types around 3 1/2 in foam."
> 
> Am I the only one that does not understand the above sentence?


 Nope.


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## Prologus (Oct 30, 2014)

*Me Neither*

Perhaps the word foam is a typo?


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## bzguy (Jul 11, 2011)

Hazzard wood?
Sounds weird to me also, only thing I can think of is......
There was a company in VT that started making 4' X 8-16' panels of OSB glued to 3-1/2" foam, but they came with sheetrock on the opposite side.
You put up a post and beam frame and spiked these panels to the outside of it for a pretty nice looking interior. 
Sounds like the same material?


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## tvman44 (Dec 8, 2011)

I prefer the router. :thumbsup:


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## Muzzy17is (Sep 14, 2014)

Man y'all are a tough crowd. I never me a bunch of wood workers were so grammatically inclined...lol. Ok I'll fess up to the typos. Hazzard wood should have been hard wood and foam should have been diam. This I phone is touchy sometimes...lol


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## bzguy (Jul 11, 2011)

LOL!
Both of those mistakes happen to be real words.
How bout a 3&5/8" hole saw without the 1/4" center bit?
Put it in a drill press and clamp the workpiece down.
Fastest and easiest way i can think of, sand a bit on edge-sander if necessary.


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## epicfail48 (Mar 27, 2014)

bzguy said:


> LOL!
> Both of those mistakes happen to be real words.
> How bout a 3&5/8" hole saw without the 1/4" center bit?
> Put it in a drill press and clamp the workpiece down.
> Fastest and easiest way i can think of, sand a bit on edge-sander if necessary.


I've never seen a hole saw leave a clean cut. Decent enough, but they also seem to cup out a lot. I also saw the size and my arm immediately started hurting...

Back when I was in freshman year my shop class teacher gave me a hole have with a 4 inch hole saw, told be to put it through some 3/4 inch ply. Also told me to brace myself. Like an idiot, I started the drill, and the pilot dug in and I'm thinking "man, this ain't so bad!". Then the teeth of the saw dug in.


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## bzguy (Jul 11, 2011)

Hole saws are only as good as the "holder".
Yes they "jam", from cocking the drill to one side, hence the drill press.
If put in a drill press and work is clamped a new saw with sharp teeth will do a nice clean job.


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## Black540i (Jan 4, 2013)

Given the size, I would use bandsaw. You can also make a circle cutting jig for the table saw as well.


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## TimPa (Jan 27, 2010)

Black540i said:


> Given the size, I would use bandsaw. You can also make a circle cutting jig for the table saw as well.


i would be interested in seeing that. being a straight cutting blade, i can only imagine shaving a round edge. do you have pics?


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## Muzzy17is (Sep 14, 2014)

TimPa said:


> i would be interested in seeing that. being a straight cutting blade, i can only imagine shaving a round edge. do you have pics?


YouTube has a couple of videos on it. I think I'm leaning towards my band saw for what I'll be doing.thanks for all the replies.


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## bzguy (Jul 11, 2011)

I made a circle cutting jig for table-tops on a band-saw.
I had to hinge the pivot point so it slid a larger piece into the blade, otherwise the blade would ride on the square edge and not start a circular cut well.
Even a 36" top had to be routed after to get a clean edge.
Still say the hole saw for a tiny piece like 3&1/2".


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## Al B Thayer (Dec 10, 2011)

FrankC said:


> "I'm going to be cutting a bunch of circles out of 3/4 - 5/8 in thick hazard woods of various types around 3 1/2 in foam."
> 
> Am I the only one that does not understand the above sentence?


Count me in. 

Al


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## Al B Thayer (Dec 10, 2011)

Muzzy17is said:


> Man y'all are a tough crowd. I never me a bunch of wood workers were so grammatically inclined...lol. Ok I'll fess up to the typos. Hazzard wood should have been hard wood and foam should have been diam. This I phone is touchy sometimes...lol


Well hardwood is one word and it should be dia. 

Al


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## Al B Thayer (Dec 10, 2011)

bzguy said:


> LOL!
> Both of those mistakes happen to be real words.
> How bout a 3&5/8" hole saw without the 1/4" center bit?
> Put it in a drill press and clamp the workpiece down.
> Fastest and easiest way i can think of, sand a bit on edge-sander if necessary.


Let me add. Blast compressed air in the kerf as you cut and it will cut more cleanly and not have to stop and clear the cut.

Al


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## xmas (Nov 24, 2013)

Jpthien.com has a great circle cutting jig plan that i used to cut two circles for a thien seperator. It worked beautifully, left a clean edge (using router table) & it's infinitely adjustable if you need to trim just a little off your circle diameter as I do today to modify my baffle for a 4" hose from a 2.5"


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## Stevedore (Dec 28, 2011)

Many years ago, I made wooden toys that I was selling through a few local craft stores. Some (wagons, cars, etc.) required wheels. I made a jig for my bandsaw that sounds like the one described by bzguy above that he used for table tops.

It was a piece of plywood that clamped to my bandsaw table, with an arm attached with a screw so that it could pivot on the base piece. At the opposite end of the arm, there was a short piece of dowel glued in that was the diameter of the axle hole in the wheels I was making. I cut my wheel blanks as squares, and drilled the axle holes in their centers. I placed a blank on the dowel pin on the arm, pushed the arm into the blade, then rotated the wheel blank, with the arm stationary, to cut the round wheel. 

I haven't noticed that jig in years, but it still may be buried somewhere in my shop. If you're REALLY interested & would like to see a picture, I'll see if I can locate it.


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## Muzzy17is (Sep 14, 2014)

Al B Thayer said:


> Well hardwood is one word and it should be dia.
> 
> Al





Stevedore said:


> Many years ago, I made wooden toys that I was selling through a few local craft stores. Some (wagons, cars, etc.) required wheels. I made a jig for my bandsaw that sounds like the one described by bzguy above that he used for table tops.
> 
> It was a piece of plywood that clamped to my bandsaw table, with an arm attached with a screw so that it could pivot on the base piece. At the opposite end of the arm, there was a short piece of dowel glued in that was the diameter of the axle hole in the wheels I was making. I cut my wheel blanks as squares, and drilled the axle holes in their centers. I placed a blank on the dowel pin on the arm, pushed the arm into the blade, then rotated the wheel blank, with the arm stationary, to cut the round wheel.
> 
> I haven't noticed that jig in years, but it still may be buried somewhere in my shop. If you're REALLY interested & would like to see a picture, I'll see if I can locate it.



I'm pretty sure your jig is similar to what I'm going to build. I'll post a pic of mine when I get it done.


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## Black540i (Jan 4, 2013)

If you're going to use your bandsaw, create a jig like the first one in this link....
http://www.americanwoodworker.com/blogs/tips/archive/2010/01/12/template-routing-tips.aspx


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## 4DThinker (Mar 13, 2013)

If I had to make a multitude of a specific size disc a specific sized hole I'd invest in a small CNC. There is free web software now to draw up and toolpath the cuts (Easel) and a little CNC can also do one heck of a lot more. With a little better software you can cut tapered holes or tapered discs too. I use my little CNC to cut tapered 2.5" holes that perfectly fit shopvac hose ends for adapter plates on the assorted machines I have.


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