CNC'd speaker grills

[MattKellett]

Working as a machinist in a prototype shop I'm always thinking of parts to make for myself in my spare time - but it never happens as once I've done a days work in the shop I really don't feel like doing the same thing in my spare time. Anyway for the first time in many years I actually made something for myself.

I was really tired of the cracked grills on the rear shelf and when I finally decided to replace the speakers which had totally deteriorated I though new grills where in order. Anyway here's the photos of the first part I've made for my car......who knows what I'll do next now I have this new found enthusiasm!!!

For you techies out there, I machined on a Haas machining center, part drawn up and programmed using surfcam and machined in black polycarb.

Front of speaker.

Rear of speaker, here you can see where I epoxied in the old mesh.

This shows the Porsche text I cut in.

And...A shot of the macine shop.

I hope you enjoyed these shots and I'm sure I'll take some more photos of other parts I make for the car. I have a variety of materials at hand from most plastics to aluminum, magnesium etc., so who knows what I'll cut next!!

Matt
1987 Carrera Coupe

[87coupe]

Awesome job!

to another 87 coupe in SJ.

[kycarguy 935]

Looks great Matt. Im currently learning CNC programming and we mostly are using an Okuma and Bridgeport mill. I have been trying to think of things to make in the machine shop in my spare time and so far making machinest tools and auto body dollies. We have a spanish EDM OSU I believe is the name and an Okuma lathe also but I haven't used them much yet.

Does the polycarb clog the machine? I was thinking of making some runs of delrin and other plastics but wasn't sure because we mostly machine steel or aluminum.

Keep up the good work.

[Mysterytrain]

geez..that looks great! How about making a pair of 78/79 door speaker grilles!!

[5axis]

very nice

[MattKellett]

kycarguy - I had no problems with cutting plastics, but we have been doing so for years now. Our business in the bay area is mainly prototypes for the tech industries in the area and medical work. So we're always cutting new designs for cell phones, laptops, medical equipment etc. We cut ABS, polycarb, delrin, nylon, plexiglass, glass filled plastics etc etc. We also cut alot of aluminum and magnesium which is very popular now with the designers for pda's etc., stainless steel also for medical tools and small parts where corrosion is a problem. But cutting steel is not my favorite as we're not really set up for that. We also have a couple of regular bridgeports and a manual lathe, and an edm which has yet to be plugged in!!
Now for cutting plastics just try and keep your rpms down with a higher feed rate so you're removing an nice sized chip. For instance if I was using a 1/4 end mill I would run the cutter at maybe 6000 rpms and feed at around 40 - 60 inches/min depending on the detail. The great thing with plastics is that if you screw up your feeds and speeds the cutter will rarely break. What programming software are you using? I'm only really familiar with surfcam, and have never programmed just using g code! We do so much 3d work that that would just be insane. Anyway good luck with your work, I learn something new almost every day, screw something up big time once in a while!! Here's the web site for our company, which isn't a very good website I have to say.- prototypesplus.com

mysterytrain - Making the grills wouldn't be a problem, I just measured up my old grill and then drew it up on the cad/cam softwareand added the original mesh, it was pretty close although I made my covers with a higher clearance as the speaker tweeters stuck out more than originals. The big draw back for machining these and I really wouldn't have done it if I hadn't neede the extra clearance is the cost of the material, plastics are no longer cheap as many people think, sure injected molded parts are due to the quantity, but machine grade plastic is pretty pricey, you could probably buy new oem grills cheaper.

[RFR]

Matt,

very nice! what about a 6x9 in billet aluminum???

would look freakin' cool with a black mesh grill!!!!!!!!

[Oracle]

I like your shoes, they're shiney!

Seriously, the speaker grill looks really nice..

Good job
-Jasper

[jim72911t]

Jeeze Matt, your shop could be a Haas advertisement! Must be nice.

The grilles look great, very understated and factory looking. I'm sure you'll think of other things to machine now that you've been bitten by the bug. I started down the same path as you, and now have a small business selling a few Porsche parts.

I use Keycreator and Mastercam, but learned first by manual programming, then on Surfcam. A few years ago, I got the boss to buy me a seat of Mastercam, but no 3D yet. I've been able to do some pretty convincing 3D "looking" stuff with only 2-1/2D, you just have to get a bit creative with design and programming.

Your feeds and speeds for polycarb sound about like what I'd run, so either we both are doing something right, or neither one of us knows what the heck we're doing!

Have you checked out Practical Machinist on the web?

http://www.practicalmachinist.com/cgi-bin/ubbcgi/ultimatebb.cgi

Like any BBS, there are some people who don't know what they're talking about, but some good info can be found, as well.

Keep up the good work,
Jim

[Gordo2]

At first I thought you re-invented the speaker grilll, then I saw the Porsche script. Coooool.

Here's a project that I have been trying to figure out how/where to get done.

I want to remove the center counsel in my '83. I think it would look sharp if I had a leater shift boot held to the floor with a 1/4" to 1/2" thick aluminum wrap around base that screwed to the floor (metal just wide enough to fit around the base of the shift boot). I picture it being a rectangular ring approx. 1/2" wide, beveled sides with counter-sunk screw holes.

I don't think it would be anything to difficult to make. Main issue would be making sure it mated up with the base of a common/standard shift boot.

If inclined add that one to your list.

Nice job, Gordo

[kycarguy 935]

Matt, We are learning Mastercam 9., Mastercam X and Esprit. We are also learning manual programming the G codes which is a real pain but I guess we need to know. I need to check out surfcam too if shops are using it.

We do break some bits cutting stainless and other steels, aluminum and they make a loud CHING...lol.

Thanks for the link and thanks for the info on cutting plastics. I will have to give it a try.

[equityr]

Matt, I have an 83 911sc and I need a pair of the 4 X 6 rear speaker grills. Can I buy them from you.
Thanks,
MIke
equityr@aol.com

[needspeed]

Hey Matt, do you still make these?

[Steve F]

As a "Haas Driver" for the last 30 years....Ya done good!