What tool to cut baffle holes?

[kvk]

What tool for Cutter baffle holes

I supposed a Jasper Jig is probably the best tool for routing baffle holes for drivers but it's about $40 which is a fair amount if you are only building one pair of speakers.

Are there any cheaper options? Does someone make something like a cheapo adjustable jig for routers?

I do have a router and bits already.

 

[Jan Dupont]

Drill a lot of holes in a circle............

 

[EC8010]

Re: What tool for Cutter baffle holes

Does someone make something like a cheapo adjustable jig for routers?

I do have a router and bits already.

Last Wednesday I made a trammel for my router and cut two perfect circular holes with rebates in plywood without any splintering. All you need is a strip of something reasonably rigid (I used 1/4" SRBP, but you could use aluminium). You screw the router to it, and at the right distance from the cutter, you drill a hole for a bolt to go through the centre of the circle you want, drill a hole that size in your baffle. Then, with great trepidation you gently lower the bolt into the hole in the baffle, switch the router on, and cut a perfect circle.

 

[john blackburn]

Try using the shank (blunt) end of the drill bit as a pivot rather than a bolt, it will be a tighter fit and wont allow any "wander" whilst cutting.

 

[cuibono]

I do the same as the above two. Not perfect, but decent.

 

[loninappleton]

If you are doing anything over 5" the above methods work well.

Hole saws are available up to 5".

What makes the Jasper work is that the center pin goes into
a metal shank and so the router will not pull out of round.

Using a circle cutter with just a pin through wood has not worked very well for me.

Other method not discussed yet is the jig saw with circle jig.
the circle jig attaches and goes for about $7 USD here.

 

[Cloth Ears]

I used the Jasper last weekend for the first time, and the ease and accuracy of the cut pays foir itself with just the four holes and rebates. Anything new I do is just going to be a bonus, I reckon.

I dunno why I tried all those other methds beforehand - the wastage of wood and time seems like such a silly thing to have gone through.

 

[loninappleton]

Jont,

As I recall Jasper had some complicated calculation to do circles.

Did you center and eyeball the right calibrated hole or use the
Jasper system?

BTW, Jaspers go on deal once in a while and as a set with a larger and smaller one.

I have some better bits now so I may give my small roto tool a whirl at doing circles with it's kit again. The pin in that rig fits snugly into a
certain gauge of T-nut. But I'm still using 4 in speaks so never did a finished circle cut with that rig.

 

[Nanook]

her's something pretty interesting..

jobmate cutout tool

Haven't tried it, but my cohort just bought one, will try it out on some small OB speakers.

stew

 

[vitalstates]

I've used this for the last 5 years with no problems at all. Pic shows the jig upside down. Its best used if the target piece is placed ontop of a piece of scrap so you can drill the centre of required hole thru both pieces.

for duplicating holes I find it much easier to cut a template with the jig tool and then just used the template.

Ed

 

[Cloth Ears]

Jont,

As I recall Jasper had some complicated calculation to do circles.

Did you center and eyeball the right calibrated hole or use the
Jasper system?

Not particularly complicated. If you use a quarter inch bit, then you just use the correct hole. I've got a half inch, so I had to use a hole an eighth less than required (for outside cuts) or an eighth less than required (for inside cuts).

I did make a mistake in the size of the cut-out (slightly too small), but that was due to measurement not the tool. The second time was much better. And, due to the width of the rebate I had to make 3 passes to do that successfully.

Worth it, I think. I've got the big one, as I'm only using it to cut out speaker holes - I don't do vented speakers.

 

[ScottG]

Zaph cuts a LOT of baffle holes for driver testing (..and projects). Note his comment here (March 17, 2008):

http://www.zaphaudio.com/blog.html

"I love showing off a nice clean baffle. Once again, I'll say the Sears circle jig kicks the Jasper jig's ***. How obsessive/compulsive am I? When I cut a driver countersink, before I mark and predrill the screw holes, I'll center the driver in the opening using 4 pieces of folded over post-it note. If the post-it note requires fewer than 3 paper thicknesses, I'd call it failure - if for some reason I had to repaint the baffle, there's a chance that the driver would not fit a paint thickness. If it requires more than 5 paper thicknesses, I failed again by making the countersink too large. Luckily, I pretty much nail it with a 4 paper thickness gap every time, as I did in this image. Try that with your Jasper jig.

The "Craftsman Multipurpose Router Guide" is Sears item# 00925179000 and Mfr model# 25179. $18, and 1/64" accuracy... in the right hands with enough practice."

 

[MJL21193]

I use the following for great success!

Starting with my trusty brace and bit, I drill a hole big enough to start my keyhole saw. Once a nice neat hole is cut, I use a combination of marking gauge and router plane to cut the recess.

Piece of cake!

 

[Cloth Ears]

I use the following for great success!

Starting with my trusty brace and bit, I drill a hole big enough to start my keyhole saw. Once a nice neat hole is cut, I use a combination of marking gauge and router plane to cut the recess.

Piece of cake!

But John,

you've had years of practice at doing this and I wouldn't trust myself to saw a straight line without some sort of jig/brace/form to keep me in line.

A man's got to know his limitations (someone said that before I think). And I have lots of limitations but I just try to find a way around them instead of getting someone else to do the work.

Makes for slow progress, but I can say it's all my own work!

 

[pjanda1]

Starting with my trusty brace and bit, I drill a hole big enough to start my keyhole saw.
Piece of cake!

Nice brace. I haven't seen many, but I've never seen or used a wood one.

I haven't flush mounted any speakers I've built, but they were all larger fullrangers or subs. If you aren't flush mounting, you don't have to be super accurate. I use a rotozip freehand. I've tried their circle guides (both) and they are terrible for thick material. With a skinny bit, you can probably cut freehand circles with your router. Heck, I've heard of some folks freehand routing the recess for flush mounted pincushion shaped drivers.

pj

 

[loninappleton]

What's a pincushion?

The method I used my first couple tries was:

Cut the driver hole with a hole saw.

Position the driver.

Pilot some holes for the screws

Screw the thing down.

Draw an outline on the surface.

Free hand flush mount with roto zip tool
and 3/8 bit (to make the corners.)

Rotozip-type tool has real high speed and I steadied it as best
I could. Latest job was on the FrankenBIB. Do not go
below about 1/8 in for Fostex. I did 3/16 and it was a little deep.

For jobs like the BIB, be sure to factor the depth of the flush mount
when cutting your stock. I tried to flash mount after a completed build and the driver hit the back after the cut out was made. I got around that and hence renamed the project the FrankenBIB. I'm listening to it now and it's back in service.

 

[kvk]

Zaph cuts a LOT of baffle holes for driver testing (..and projects). Note his comment here (March 17, 2008):

http://www.zaphaudio.com/blog.html
...

The "Craftsman Multipurpose Router Guide" is Sears item# 00925179000 and Mfr model# 25179. $18, and 1/64" accuracy... in the right hands with enough practice."

My router is a Skil 1810. Anyone know if router bases are standard and the Sears jig will fit?

 

[Henkjan]

there are plenty DIY circle jigs around

like here (it'sin german)
http://www.uibel.net/bauvor/bv_tutorials/fraeszirkel/d_fz.html

 

[renfrow]

If you already have a jigsaw, just draw the appropriate sized circle and free hand it with the jigsaw. Most speaker bezels will cover up any wobblies off the line. If not, and you already have a router, or roto type tool, then buying a circle cutting attachement is a good investment, seeing as how you're going to have to buy something anyway. (I have the small jasper jig, and like it, but, I wish I had the next larger one.)

Tom.

 

[Nanook]

jobmate cut out tool

seems the link I provided just takes you to the home page of Canadian Tire.

The part number is 54-8229-2.

stew