[gregmcquaid]

Hi,

I have a bit of an issue and i was wondering if you guys have any advice for me.

Basically i have cut a circle out of my front baffle for my subwoofer box i am building and to cut a long story short i have managed to cut the hole to small and the subwoofer driver wont fit.

I have cut a circle that is about 11" and it needs to be 11.625".

Whats the best way to make the hole bigger?

Regards,
Greg

 

[Blaser]

Welcome to the Shack Greg.

Being smaller is better than bigger indeed. So what I suggest is to draw the correct circle you need to cut and use an arc cutting machine. You may use a bolt attached to another wood sheet at the center of the cut (make sure the largest radius of the cut is smaller than the new one you should draw).
I don't know if I'm clear, you tell me...

 

[hddummy]

I can definately help, but I need a little bit more detail. How thick is the baffle? Are you flush mounting the sub or surface mounting it? If you are flush mounting, which circle are we talking about? In the long run, you really only have two options. You can cut a circle and temporarily fill the hole so you can find you center again and reroute the hole bigger. This may not be possible if the box is already sealed. You can also take a clean sheet of MDF and create a circle template. Use a guide bearing or a flush/match routing bit to cut the right size hole in the box. Fill in some of the details and we can get this squared away no problem.

 

[gregmcquaid]

Hi,

The baffle is 25mm thick and i am surfice mounting the woofer. The box is not assembled yet.

 

[ironglen]

Hi Greg, I believe that you did the same as I, except my outer baffle face is probably too small (and slightly offset from the two interior baffle boards which I will bolt the driver to) So, I am now going to take one of the circles I previously cut out and mount it within my too-small circle to have a 'center' to attached my router jig's pivot point. I'll do this by mounting both my baffle AND the previously cut circle to another larger board. This larger board will effectively create a base for the whole setup and allow you to mount a router within the previously cut circle, without the center moving around. I hope this helps.

 

[hddummy]

Exactly what I would do. If you have any other questions, just shout.

 

[Bent]

do you happen to still have the circle cut-out?

edit - ahh never-mind, it looks like I shoulda read a bit first.

 

[gregmcquaid]

Thanks guys i will give this a go and let you know how i get on. :T

Oh and Hello from the UK :wave:

 

[Scaper]

Hi,

The baffle is 25mm thick and i am surfice mounting the woofer. The box is not assembled yet.

If you're just surface mounting, the easiest solution is to just draw the correct sized circle on the baffle, then use a jigsaw. Should be very easy.

 

[Fabricator]

If you're just surface mounting, the easiest solution is to just draw the correct sized circle on the baffle, then use a jigsaw. Should be very easy.

yep. if its a little off = who cares, it will not be seen.

 

[solid7]

You can also buy a thin piece of material - anything harder than cardboard will do - and cut a template. Basically, make the proper size hole, cut it out in the thin material, and then center it over your "too small" hole. From there, you use a flush trim router bit, (one with the bearing on the shank of the cutter) and let the bearing follow your template as it cleans up the smaller diameter. I personally don't like chiseling out a saw cut hole, and I have a penchant for perfect circles, so for me, this is the best way. Plus, using the template, you can get both circles exactly the same size...

When you finish, save it for later. That way, you can use it again when you add your next subwoofer.

 

[vili]

I agree with the jigsaw idea. Since you aren't flush mounting you don't have to deal with multiple layers of mdf. Trace out the area you want and cut the circle, just be sure to cut it a little smaller than bigger, you can always sand it down a bit if it is too small but cant do much if its too big.

 

[gregmcquaid]

After more inspection the hole was not as small as i first thought and i managed to use some heavy sandpaper to get the hole just the right size.

Thanks for all of the sound advice though guys.

Cheers,
Greg