Someone in our area came up with a nice idea called the “Urban Workshop.” They offer the public access to any of the new high tech tools and provide the classes for the people to learn how to use them.

I’m talking HAAS CNC mill, lathe, welders, Auto tools/lift, laser cutter/etcher, PROFESSIONAL 3-D printer…, the works!

I will be checking this out this week for sure!

http://urbanworkshop.net/

Listing of tools offered for use:

Abrasives

Disk and belt sanders

Two large cabinet sand blaster

Wire wheel, pedestal mounted

Arts and Crafts

Vinyl cutter, computer controlled by Roland

Soldering irons and wood burning kits

Assembly Work Area

10 Large work tables with vises

Compressed air and electricity at each table

Bin wall for sharing parts and materials

Great for work groups, club meetings, or events

Automotive

Floor jacks and jack stands

Large assortment of specialty automotive tools

Air tools

Alignment tools

Diagnostic computer equipment and scanners

Shock Dyno, Rohrig

Battery charger

Waste oil and coolant collection

Ceramics and Glass

Skutt kiln GM1018 (24″ x 24″)

Computer Lab

Dell Workstations with large monitors

HP Color printers

HP Large Format color printer with roll feed

Fax, scan and color copier

Engineering software (Fusion 360 & Solidworks)

Design and photo editing software (Illustrator, Photoshop, Corel Draw)

Video editing software

CNC programming software (Aspire & HSMWorks)

Internet access / WIFI

Co-working space and Conference Room

Tables and chairs for work, meetings and events

55″ Flat screen TV

Overhead projector

Refrigerator and freezer

Bose public address system

Electronics Lab

National Instruments Virtual Bench and MyRio

Soldering, resoldering, and fume extraction equipment

Wide assortment of crimp and connector termination tools

Amscope binocular microscope for board work

Multi-meters

Oscilloscopes

Signal generators

DC power supplies

Fabrication

Chop and cold saws

Drill press

Vertical Band Saws

Tubing Bender

Fabrics

Juki single needle sewing machine (Industrial)

Juki walking foot sewing machine (Industrial)

Juki Overlock Machine, Serger (Coming soon)

Embroidery machine, computer controlled (Coming Soon)

Cutting and layout Table

Four color Silk screen machine

Hand Tools

Large assortment of hand and cordless power tools

Layout and Measuring Equipment

Romer CMM arm, Infinite model, 3 meter volume

Large Surface plate

Height gauges

Calipers, digital and dial

Micrometers, digital and dial

Machining

Bridgeport mill with Digital read out and tooling

Lathe, Large metal lathe with tooling

CNC Vertical Mill, Haas TM-2P with tooling – Brand new

Plastics

Belovac BV Class C 24″ x 48″ Vacuum former

Morgan Industries injection molder, Model G-100T

Vacuum Pump and resin traps for composite vacuum bagging

Carbon fiber and fiberglass lay up area

Heat strip bender

Prototyping

3D Printer, Dimension Elite FDM, ABS plastic, .007″ resolution

Epilog Helix 50 watt laser etcher with rotary attachement

Epilog Zing laser etcher, 40 watt

Pressure vessel, 55 Gal, 24″ diameter, heated for making silicone molded parts

Sheet Metal

Box and pan brake

Jump Shear, 48″ wide

Mittler Brother bead roller

Planishing hammer

Beverly Shear

Corner notcher (Coming soon)

Misc hand shears and tools

English wheel (coming soon)

Rotary turret punch (coming soon)

Slip roll, powered, (coming soon)

Surface and finishing

Aluminum anodizing

Outdoor Spray painting area with part rack

Powder coating station and oven (Coming soon)

Welding

Miller Welder, TIG (2x)

Miller Welder, MIG (2x)

Chicago Electric Welder, Spot

Oxygen and acetylene torches

Plasma cutter, hand held (coming soon)

Plasma cutter, CNC, 4′ x 8′ (coming soon)

Wood Working (all new equipment from Laguna Tool)

CNC Wood router, Laguna Smartshop 1, 4′ x 8′ bed

Table saw

Compound miter saw, sliding

Table router

Shaper

Mortiser

Band saw

Belt/disc sander

Scroll Saw

Drill press

We went to check it out today! A very cool set-up indeed. Third largest in the nation of its kind.

What’s nice is that you don’t need to bother with expendables such as sand paper, solder, blades, etc. nor bring your own as they are included. And, they have a hot air soldering station with binocular microscope for doing small stuff. (http://largescalecentral.com/externals/tinymce/plugins/emoticons/img/smiley-yell.gif)

I may be able to make a deal with them and trade class time in the various disiplines to let them use my machine to teach set-up and maintenance of 3-in-1 metal machines. There are a lot more ShopMasters, Grizzlys, Smithys, Harbour Freights, Jets, and half a dozen other make Chinese machines in home use than the big HAAS CNC and Bridgeport mills, and they could see if there is interest at no cost to them. Such a trade could save lots of coin on both of our parts and get and keep my machine running right. If they found there is the market for this avenue, they could get their own.

You have to take their basic safety class and classes on the various pieces of equipment before you can use that equipment…, which makes a lot of sense. Classes are $65-$125 and are very small (3-10 people).

They are 11 miles due south and we can accomodate an entire class’s vehicles in our driveway.

There are actually people who run their entire business out of this place. Not bad to pay $125/month for your office space, and they throw in all of your tools and computer/web/interface for nada. And they have a full kitchen.

Video Tour:

Todd - we have similar maker spaces in Pittsburgh - the nicest is called TechShop - see:

http://www.techshop.ws/pittsburgh.html

there is also HackPittsburgh - see:

http://www.hackpittsburgh.org/

and one for children:

http://makeshoppgh.com/

These are really wonderful resources for the city and its residents.

dave

We decided to join today. They have a reduced 1-month trial rate of $125 for Linda and I.

Our membership actually begins on Tues and we will take the laser cutter/engraver class that night (offered once a week) so can start using it immediately, as well as the 3D printer (no classes necessary for that one).

Should be fun.

We started last night with the laser etcher/cutter class and also have access to the 3D printer. The laser is great for making signs from acrylic.

Unfortunately, while use of the printer and laser are included in the membership, the media are not. For the laser, you just bring in what you want to cut/etch, if it is on the approved list.

For the 3D printer, they supply the ABS media in cassette spools. The media costs $10/cubic inch! I have a few designs that I’ve been working on and to print them out would be on the order of $200 each and they are used in pairs! While that may not be a lot for prototyping, I can’t sell product at that cost. I would have to print one, getting it as exact as possible the first time to reduce subsequent runs getting it right, and make a mold from that and cast them as resin.

Also I wanted to make the “plates” out of ABS plastic as they would cost about ~$18-$20 each to print (x 8), but the laser won’t work with ABS or PVC plastics as they emit toxic fumes that cloud the lens. Acrylic works, but I want 1/16" and that typically comes in 1/8" and is not as strong as ABS.

I was able to get on the laser etcher/cutter today. Look what I can do.

That doesn’t look like trains to me. LOL But I like it!!

I took the wood shop class today (3 hr). Just two of us in the class. He goes over safety, then the set-up and use of each machine and its idiosyncrocies. Now I’m certified to use all that stuff and can use it free of charge whenever they are open.

Friday I do metal shop and will be able to use that stuff too.

Made some parts today. Still getting everything fine tuned before I use virgin materials.

BTW, this is what we are shooting for except scaled and made to mount to the tweeter rather than the midrange horn.

This shows a pair of the slant plate assemblies hot off the laser. Note the protective coating on all pieces to keep them from scratching.

(http://www.audioheritage.org/photopost/data//500/medium/Resized_Slant_Plate_Assembly.jpg)

“Baby we were born to run.” It would seem that the US Postal Service had us in mind when they designed their “If It Fits, It Ships” box. (http://www.audioheritage.org/vbulletin/images/smilies/wink.gif)

(http://www.audioheritage.org/photopost/data//500/medium/Resized_Shipping_Box.jpg)

A bit more testing for the best angle with the 1/16" plates and we should be good to go.

Also:

(http://www.audioheritage.org/photopost/data//500/medium/Parts_Resized.jpg)

The stands assemble with a strong friction fit and no glue is necessary for their assembly, even under the cantilevered weight of the tweeter. The “feet” are contoured to accomodate the ferrite magnet.

(http://www.audioheritage.org/photopost/data//500/medium/Stands_1.jpg)

(http://www.audioheritage.org/photopost/data//500/medium/Stands2.jpg)

Tolerences are purposesly kept tight with the speaker mounted as low as possible relative to the feet.

(http://www.audioheritage.org/photopost/data//500/medium/Tweeters1.jpg)

(http://www.audioheritage.org/photopost/data//500/medium/Tweeters2.jpg)

This is very interesting Todd!

I know that anyone can claim anything on the Internet and it means nothing unless they back it up. I also know that no one can hear the sound of the 075 over their computer monitor, unless that’s what they listen to on their computer.

So if a picture is worth 1,000 words, a video is worth a vocabulary. This shows the Behringer 61-band RTA running pink noise, with and without my slant plate assembly on a JBL 075 ring radiator (tweeter). The microphone was set on-axis 1 meter from the tweeter. You can see as the plate is added/removed and results on the RTA.

This is through the crossover with a frequency of ~7,500 Hz. The midrange is turned off so as not to confuse the reading for the tweeter.

The tweeter displays the typical 075 hole just about 9kHz with a 10kHz peak and just above that creating a step. The hole removes inteligibility and the peak/just above give the tweeter that “In your face” sound that is fatigueing over time/in no time.

Note that when the plate assembly is added, the 10kHz and just above peak is flattened (~6 dBA) and the whole band becomes much flatter. The “hole” is reduced relative to the surrounding frequencies and the whole thing is just way smoother sounding.

[video=youtube;08VbkOmXXPw][/video]

This demonstrates my design when used on the 075 ring radiator with the standards JBL N2400 crossover. The idea is to produce as flat a frequency response as possible above the 2,400 Hz crossover point.

I’ve reduced the dB span in this range from about 20 dB to 10 dB representing an improvement of 10 times the power in the response curve.

Validation from one of the highest sources in audio, Nelson Pass!

https://en.wikipedia.org/wiki/Nelson_Pass

Hi Todd,

Those are very cool. At this moment my JBL tweeters are at Pass Labs
in the custody of Kent English, who is slowly refurbishing my L300’s.

I will pass on your kind offer for the moment, although I do have some
horn based projects in mind for next year.

Those are so attractive I think you could probably have some success
offering larger versions to go with midrange horns as well.

Please keep in touch as you develop this further.

best, np

From: [email protected]
Sent: Thursday, September 01, 2016 11:36 AM
To: [email protected]
Subject: New Product for an Old Favorite

Dear Nelson Pass,

My name is Todd Brody and I have a background in noise and sound. I’m writing to you because you are legendary and also believe in the home hobbiest. You also have a history with the JBL speakers and my JBL quasi-L300s include most of the mods that you did for the L300 crossovers, except that I did them before your article came out. Great ears hear alike!

I’ve come up with a new product for an old favorite and would love to have your take on it.

The product is an acoustic lens assembly for the JBL 075/2402 bullet tweeters. As you know, the 075 came to be in 1956 and there were literally hundreds of thousands of these made.

You also know that this was largely replaced in the studio and home listening environment by the 077/2405 when it came out in 1971 and even though they are really almost the same tweeter, the 075 instantly fell from favor. I have quasi-L300s (AlNiCo 2235, 2420 with original tangential diaphragms on long horn, 2405) and with this modification, in listening tests, the 075 easily replaces the 077, maybe with even better articulation and vocal presence.

The faults of the 075/2402 are the continually rising frequency response with the ~9 kHz step/hole that removes intelligibility, followed instantly by the 10 – 12 kHz peak that causes sonic fatigue and has been known to “bore a hole through your brain,” and continually falling after this point. Its strengths are its extremely high sensitivity and dynamics.

The links take you to two YouTube videos demonstrating my lens. The first crosses the the tweeter over at 7,500 Hz (20160830) and the second at 2,400 kHz as used with the JBL N2400 crossover (004.MOV).

Assuming that you have access to a pair of JBL 075/2402 tweeters, I would love to send you a pair of assemblies for your testing. I will try to market these at $75/pair.

Thanks,

Todd Brody

Crossed over at 2,400 Hz

https://www.youtube.com/watch?v=_V29HA9JFU4&feature=em-upload_owner

Crossed over at 7,500 Hz

https://www.youtube.com/watch?v=08VbkOmXXPw