Cabinet builders: Which circle cutting jig?

[Finleyville]

Anyway...

I was going to pick up the Jasper jig combo from parts express until I noticed their other jig offering here.

Has anyone used both? Which ones work better? Is there any other solution that makes PRECISE circles for cutouts and countersinking drivers in baffles?

Thanks all...

Oh, BTW, will the Jasper jigs fit the DeWalt 618 series? They only mention fitting the 621/625 models..

[---k---]

I have the Jasper Jig, it works fine. You won't go wrong with it. They are slightly cheaper, and have the measurements on them so it is harder to cut the wrong size. The Router Buddy is ifiitely varible and will let you get an exact size, but it is more expensive and you need to make sure you measure twice and cut one.

Zaph recommended a different one in his blog once. Iirc, it was a from Sears, maybe this one: http://www.sears.com/shc/s/p_10153_12605_00925968000P

And then people like CJD just uses a scrap piece of mdf which he drills two holes in. Works just fine and is basically free.

[Silversmoky]

I have both, the jasper and the Router buddy. I like both but I definitely prefer the jasper jig. Very easy to use and simple to change sizes. The router buddy is slower and you have to be very exact on your measurements as K mentioned. The jasper jig takes the guessing out, which is nice.
I can't say for sure if it will fit your router but I am guessing that it probably will. It fit my Milwaukee router fine and they don't even mention Milwaukee.

[timmay1969]

The Jasper Jig is awesome. It fit my Rigid router nicely.

THe JJ is almost fool proof, except my first...

[LHD]

Anyway...

I was going to pick up the Jasper jig combo from parts express until I noticed their other jig offering here.

Has anyone used both? Which ones work better? Is there any other solution that makes PRECISE circles for cutouts and countersinking drivers in baffles?

Thanks all...

Oh, BTW, will the Jasper jigs fit the DeWalt 618 series? They only mention fitting the 621/625 models..

I just bought a 618 today that the jasper fits.

[Rolex]

I have the jasper jig and find it is not as accurate as I would like. I prefer tight tolerances around the drivers. I do not find 1/16" increments enough. Though I have not picked up a different one. I used a scrap piece of mdf before that. It works alright, but is time consuming to get exactly the right size.

[LHD]

I have the jasper jig and find it is not as accurate as I would like. I prefer tight tolerances around the drivers. I do not find 1/16" increments enough. Though I have not picked up a different one. I used a scrap piece of mdf before that. It works alright, but is time consuming to get exactly the right size.

Just wondering if you could undersize your hole and fine tune fit/finish with sandpaper or emery cloth. It would be time consuming but you're only removing less than 1/16", right?

[cjd]

Just wondering if you could undersize your hole and fine tune fit/finish with sandpaper or emery cloth. It would be time consuming but you're only removing less than 1/16", right?

You're not that accurate. It's NOT fun.

If you use 1/4" HDF and drill with a brad-point on a drill press (I don't, I drill by hand, which means I never drill exactly perfectly straight through) you can get as accurate as your patience allows. I use a 1/4" pin as well.

[Finleyville]

Thanks for the responses.

My first inclination is to totally go DIY and just make one whenever I need one. Like cjd, I do not own a drill press to make exact holes for this to work. So I am reluctant to follow this route.

If you consider the Circle Buddy replaces both JJ 200 and 400 models then it is only $5 more from PE.

Silversmoky: Has the Router Buddy ever become untightened during a cutting operation causing you to mess up a cut? I guess that is my only worry.

I see now that the JJ's will fit my router and are much easier to use. But with more and more drivers having unusual or metric OD's for countersinking operations I am wondering if I will be creating more work getting close and sanding to exact fit than measuring thrice and cutting once. Hmmmmmm...

[minkuni]

I use the N-Compass and I am very happy with how easy it is to use. I have tried the Jasper Jig and got annoyed at the difficulty of hitting the right hole on the JJ for circles with a radius smaller than the base plate of the router. With the N-Compass I do a rough adjustment before a test cut and then fine-tune the radius with the thumbscrew. I have not had a problem with the jig getting out of alignment during a cut.

[---k---]

I have, not intentionally, undercut the size of several driver openings and had to increase them using sandpaper. THIS IS NOT FUN OR EASY. I have tried using sand paper wrapped around a small dowel and a Dremmel tool. But, the problem is that the is just no way to make sure that you are sanding uniformly around the whole perimeter. You're also sanding a very small edge that is difficult to sand and it is easy to round over that edge. The sandpaper will wear quickly, and you are constantly having to rotate it. It is just not something you want to do.

[Silversmoky]

Thanks for the responses.

Silversmoky: Has the Router Buddy ever become untightened during a cutting operation causing you to mess up a cut? I guess that is my only worry.
.

No, once you set it and tighten it doesn't move. It is a pretty nice system. I like both for different reasons, and will continue to use both, but overall I like the jasper better. I always do a practice circle on some scrap just to make sure the size (both depth of countersink and diameter) is where I want it. I like the circles very tight and haven't really had any problems getting them so with the jj but it is a little trickier with the router buddy. Hope that helps.

[Hdale85]

My only complaint about the jasper jig, is that they put the writing on the bottom side of the router. Some times it's a pain. I find that taking a sharpie and putting a little dot on the one you need helps a lot.

[ThomasW]

I have tried the Jasper Jig and got annoyed at the difficulty of hitting the right hole on the JJ for circles with a radius smaller than the base plate of the router.

Correct, this is one of it's downsides. For tweeter sized holes I use hole saws. For anything larger I much prefer the Jasper Jig simply because it's so fast to change hole diameters and maintain accuracy.

[eyekode]

I have, not intentionally, undercut the size of several driver openings and had to increase them using sandpaper. THIS IS NOT FUN OR EASY. I have tried using sand paper wrapped around a small dowel and a Dremmel tool. But, the problem is that the is just no way to make sure that you are sanding uniformly around the whole perimeter. You're also sanding a very small edge that is difficult to sand and it is easy to round over that edge. The sandpaper will wear quickly, and you are constantly having to rotate it. It is just not something you want to do.

I think we have all under-cut a hole . My favorite way to fix this in MDF is to take a chisel and use the back side of the blade as a scraper. It takes forever but works really well and if you keep moving in a circle you will not oval your hole.

[Finleyville]

eyekode: good tip


Well... I just ordered the Router Buddy along with my parts for my Noobersters MTM. It sounds like the JJ's would work easier. But since I do not make many speaker holes I do not mind precisely measuring the jig to get the exact result I need.


Oh, and BTW I scored at Harbor Freight today!!! For around $60 I picked up four 4' square bar clamps and two 5' square bar clamps! Now I just need a tower speaker project to use them!

[Hdale85]

I got aluminum channel clamps from there for about that much. I only got 5 though but I think it was like 40-50 bucks.

Did you say in another thread that you're building the noobsters for someone?

[eyekode]

If those are the aluminum channel ones with blue clamping surfaces (like these http://www.harborfreight.com/cpi/cta...emnumber=38184) take them back. They are horrid. I bought two and they both bind really badly now.

I also bought 6 of this style clamp from them: http://www.harborfreight.com/cpi/cta...emnumber=34387

2 of the 6 are stripped.

I don't think I will buy any more of their clamps.

[Hdale85]

Those would be the ones I got and I've had them for...I don't know 6 months now and haven't had any issues. I actually find their clamps to be quite a bargain. Obviously if I was building stuff constantly I'd probably buy a bunch of nice clamps but right now I don't have the space.

[Finleyville]

Yeah, those were the ones I purchased too. If I actually needed to use the clamps more than once a year then I would invest in quality ones. Otherwise, these do the job just fine for now. That is until they all bind or strip on me. :blowup:

Dougie: Yes I am building a pair of the MTM noobsters for someone else.

[---k---]

I got a pair of those too!

[chrisn]

I have the jasper jig and find it is not as accurate as I would like. I prefer tight tolerances around the drivers. I do not find 1/16" increments enough. Though I have not picked up a different one. I used a scrap piece of mdf before that. It works alright, but is time consuming to get exactly the right size.

I haven't tried this yet so my idea may be flawed, but on the Jasper jig, if you drill a hole half-way between two sizes along the line, would it not be a 1/32 difference?

I have the sears jig (for my sears router) and it can be difficult. When using it I maintain a death grip on the adjustment handle while routing because it has come undone more than once. One of the threaded holes stripped out as well, and the little pin has come loose. The pin fell though into the cabinet once, before I knew not to drill the pilot hole all the way through. I had to cut a hole in the baffle with a jig saw just to get the pin back (It was the only baffle I ever glued on before routing the holes). I screwed up the other baffle when the jig un-adjusted itself. Those were the ugliest speakers I ever made Having said all that, it can work quite well, and I've routed many good circles with it.

I have the JJ and use it with my Hitachi plunge router. It works good so far.

Finleyville: Good luck with your build, post lots of pictures too

[JonP]

I also bought 6 of this style clamp from them: http://www.harborfreight.com/cpi/cta...emnumber=34387

2 of the 6 are stripped.

I don't think I will buy any more of their clamps.

Huh... I have about 10-12 of them, bought over a few years, I don't use them very often, but I've never had one with stripping problems so far, knock on MDF. Maybe look them over for manuf quality before buying them? I consider them a good deal.

[Bill Schneider]

I haven't tried this yet so my idea may be flawed, but on the Jasper jig, if you drill a hole half-way between two sizes along the line, would it not be a 1/32 difference?

Yes, that would work. You'd want a drill press for accuracy though. Any error in placement of the new hole gets doubled when cutting circles.

I've tried it, although my drill bit wandered some even using my drill press (yeah, I was in a hurry). Perhaps brad point bits would work better than a standard twist drill when used with an accurately placed center punch or awl prick.



You can also see from the picture that only holes for larger diameters will work. The holes for cutting smaller circles are spaced too close together. There's an occasional router screw mounting hole to work around too.

[dlneubec]

I've not used it, but here as another circle jig that someone recommended over the jasper in another forum:

http://www.shaka.co.nz/sparc.html

[Rolex]

Yes, that would work. You'd want a drill press for accuracy though. Any error in placement of the new hole gets doubled when cutting circles.

I've tried it, although my drill bit wandered some even using my drill press (yeah, I was in a hurry). Perhaps brad point bits would work better than a standard twist drill when used with an accurately placed center punch or awl prick.



You can also see from the picture that only holes for larger diameters will work. The holes for cutting smaller circles are spaced too close together. There's an occasional router screw mounting hole to work around too.

I've done this as well with my drill press. You want to be careful though. The straight line on the jig is only a graphical indicator. You really should draw the appropriate sized arc between the two holes and drill a new hole on the arc. Seems a little picky, but we are talking about tolerances less than 1/16".

Sanding the hole larger is one of my least favorite tasks. I have also used the back side of a sharp chisel. I've even been known to sand he paint off the edge of the driver.

Making your own jig does work well, but like I said, there is a lot of time required in getting the size exactly right.

[Rich Jura]

Jasper Tuning

I purchased metric and the various odd sized bits such as the undersized plywood bits in a quest to get a better fit. Draw my circle and see which bit an hole gets the tightest clearance. I have since gone to the router buddy.
Use the buddy for the recess and the jasper for the through hole.

Later
Rich

[cfbuck]

Adjusting the circle larger

My diy jig consists of a 1/4" lexan router plate. I try to make the circle as tight as possible but I sometimes err on the side of tightness. This is revealled when a sample hole is cut in scrap. I usually cut 3 concentric holes in the scrap piece, removing enough material to allow the driver basket to drop in the cut for testing of the fit.

If I have made the circle slightly too small, I don't want to remove the jig from the router and drill a new pilot hole for the pin. Instead, I use a slightly larger pilot drill in the baffle, say 9/64" instead of the 1/8" pilot. The pin will fit loosely. Recut the circle holding the router tight to the outside of the pilot hole as you move it around the edge. It should enlarge the circle by a 32nd inch. I think that I have used a 5/32" bit for the pilot hole and cut it successfully.

If I have cut the circle oversized, I glue a piece of veneer slightly larger in width than the depth of the rabbet to the inside of the circle, carefully cutting it to length so that the veneer fills the entire circle. Then trim it flush to the surface of the baffle. Try these ideas to eliminate the handwork with sandpaper.

[jbateman]

If you typically cut the mortises with a 1/2" bit in a Jasper Jig, you can tweak the openings a little by switching to a 31/64" bit. this will give an opening aprrox 1/32" smaller than the 1/2" bit would produce...given the same center pin setting.

It also allows you to increase a slightly undersized mortise by 1/32...by switching to the undersized bit, but using the next 1/16" increment on the jig.

[Ray_D]

I have a couple dozen of the Harbor Freight steel bar clamps and not have had a problem with them up to about 24" in length. In fact I think they are a great bargain. Longer they are too flexible to be useful. I have a couple of their aluminum clamps and did not think they were satisfactory from several standpoints. Their pipe clamps are alright, but their bar clamps are less expensive and plenty good enough for MDF.

Ray

[aqus]

rotating

Are there any jigs available, or I can make one that the router rotates on it. All these jigs you have to walk around the work piece all the time. I have about 42 holes to make (Dynamic 4T and 4CC inner and outer baffles) and will probably get dizzy...
I know I have seen one somewhere but can't remember where.

[Finleyville]

Even when using my plunge router with vacuum attachment I never walk around the piece. I am careful how and where the cords and hoses are right before I start the cut. You should be able to rotate your plunge 360 deg by standing in one place.

As long as the work piece is firmly secured to a bench then you should be able to change your grip on the tool while plunged down but not cutting. I end up cutting about a third of the circumference before stopping the cut, leaving the router plunged in the MDF, and moving my hands to better rotate the router around. Yes, I let the router bit come to a complete stop before letting go.

Oh, and all of this cutting was using the Router Buddy. You have to measure thrice and do some simple math to account for the center pin, but my speaker flanges are countersunk like they were commercially CNC'ed. I did all my measurements with a digital caliper to the tenths of mm.

[atm98]

I made my own jig. Had to do a second jig for the sub project. I was after +/- .005" Never made it but got close.

[CraigJ]

Aqus,

Is this the post you were looking for?

https://www.htguide.com/forum/showthread.php?p=271722&highlight=circle+jig#post2 71722

It's Pete's excellent thread about veneering and making a circle template. Unfortunately, the pictures are missing, but still easy to follow.

Craig

[aqus]

Aqus,

Is this the post you were looking for?

https://www.htguide.com/forum/showthread.php?p=271722&highlight=circle+jig#post2 71722

It's Pete's excellent thread about veneering and making a circle template. Unfortunately, the pictures are missing, but still easy to follow.

Craig

exactly what I already saw thanks...

[PMazz]

Sorry for the missing pics. I threw it up on it's own page. Circle Jig

[collo]

I made my own using the slide rods that came with the router.






Not large enough for an 18 inch driver though. For an emergency, single use solution, this actually worked!

[aqus]

Collo you inspired me. So I did this and worked great.

[collo]

Collo you inspired me...

love it!