USM-2 DIY Speakers (ND91-4 + ND16FA-6)

Yeah. I still think I would have had a much easier time with the Jasper. The Dremel circle guide is dirt cheap, but it does not give you precision. One has to hand adjust it, while the Jasper is fixed and 1/16" accurate. Given the dremel size, it is also not as steady as a full size router. The router is huge relative to the baffles I'm cutting though.

In the end I cut the circles smaller than I specified, and adjusted the diameter with a set of half round files to get to the targets.

The joints where cut with the router and those came out relatively fine. I'm a bit worried about one of the holes for mounting the woofer. I had to reduce a bit of MDF to allow the driver to sit and the edge is close to one of the holes. This is due to the driver +/- assembly which is attached to the driver basket and blocks proper seating. Will have to be careful on that corner.

I will route the edges of the baffle with a half round bit to give it a better look. But we will see. I have to wait a bit for the ports to come. The crossover parts should be here this week.

Need to relax a bit. Learning about tools and how to best use them.

 

BTW guys, any pointers as to how to go about this (on any aspect of the build) are appreciated. Learning as we go here.

 

Thanks @philipmorgan. Live and learn.

 

Wait @philipmorgan, you said Jasper 200J? I think that's their smaller one. Maybe using the Dremel 4000 + Dremel circle jig was the way to go after all.

I did a test drive with just using hole drill bits, but the results were worse than with the Dremel, and the freaking bits are expensive (the circular ones).

EDIT: This is what I used BTW:

https://www.amazon.com/Dremel-4000-4-Performance-Attachments-Accessories/dp/B00LUU2XFO/

The tool is on sale @ Lowes for $69 also and it included the circular jig. It covers 1/4" to 7". I had this jig before and used it with my old Dremel 395, but it cracked on me. The holes were scary perfect with the 395 + cracked circle jig, but it took a good 20 to 30 min to cut a stupid 3" hole with the 395 because it just doesn't have the juice. Furthermore, the Dremel jig is cheap and works well, but it is not very high quality and hard to get right. Lot's of test holes before committing. And in the end I cut short to fine tune with a file. Lot's of work.

Things get much easier with larger surface. I'm thinking larger speakers are easier. Live and learn.

 

I'm proly going to give this approach a shot (not sure yet):

http://www.hometheatershack.com/forums/diy-speakers/69767-dayton-nd91-8-04cuft-flat-packs.html

Basically new front removable front baffle (instead of the back), with the back mounted driver. I would have to route around the 3" hole since the baffle is 0.5" MDF and the driver has a 0.27" surround.

I hate the ND family (and Aurasound in general) mounting plate.

 

Thanks for all of this @Jeb! I ordered my router jig yesterday and will give it a go.

Crossover parts are here. Waiting for the port, the connectors, and the screws.

 

@ultrabike back in the day we used a ruler hacked into a beam compass to draw the circles and el cheapo $20 special jigsaws to cut speaker holes.

 

LOL! @zerodeefex I will get the jigsaw see what I get (probably very soon). I think a good jigsaw is like $70 or $90...

Just for fun.

This is indeed my first speaker ever, and wanted to do everything. Just for fun too.

 

BTW guys, this is very close to how I cut holes with the Dremel (except I use a 0.75" particle board underneath instead of letting thing free floating):



If anyone does this, get the large (relatively speaking) 4000 Dremel. Cutting needs juice and small Dremels don't got the juice.

One can see that the base of a Dremel (which is sort of a mini-router) is not very stable. This affects the finish. I expect awesome sauce results with my big boy 2 1/4 HP deWalt router and Jasper rig that is on it's way.

The jigsaw, which I will eventually get, may see some action in the future for a few quick and dirty projects in the future.

 

Definitely use a circle jig . It's like 1000x better.

Actually, I bought a router and returned it earlier this year because my neighbor is so excited to let me use his constantly. I only bought the table saw because I didn't want to walk one house over and work in his garage instead of my own

 

OK. So here is an updated drawing after using the Jasper jig and my router. Results were far superior than with the Dremel 4000. And I mean far.

Ditch the Parts-Express 1" x 4" port for this project. The reason is that the port is too thin and will not couple with standard 1" pipe elbows. It's probably sufficient for audio, but in the grand scheme of things, those ports are really crap. So the cut outs have been updated for standard 1" pipe: 1 5/16".

The tweeter really needs 1 4/16". Much more accuracy is achieved with a full size router, and a calibrated jig (1/4" bit). I used a router bit for this job with straight cuts, not a drill like one. It works great. I did not attempted to route 0.5" holes on one shot. I did it in three passes. Always go clock-wise when doing internal cuts with a router.

Here are the new drawings:



Here are the speakers as the currently stand. Note I routed the port, the woofer area, and the baffle corners:



Obviously the woofer is now back mounted. Wife liked that way so I ditched previous baffle that looked like shit. Need to clean up and beautify the boxes next. I actually screwed up the speaker binding post cut outs. I will fill them and redo later. I have all the parts for the crossovers. Will see options to mount and wire that while at the same time beautify-ing the speakers.

EDIT: One more thing. I used regular wood glue for most of this. I only used Gorilla glue for the ports given they are PVC. Be careful with Gorilla glue since it expands. I also used small triangle corner braces in the front baffle to allow easier drilling for the front baffle screws. 0.5" width is too close for comfort and the screws can crack the MDF. One also needs space to route the edges of the baffle.

 

Thanks guys!