Thursday, September 4, 2014

Frugal Horn Speakers

I've always been into DIY audio equipment. Something about it seems like such a no brainer to me since it is fairly low complexity, well test by the community and often much cheaper than commercial options.

I'd been wanting to build the Frugal Horn speakers for many years now: but never gotten around to it. After moving and getting rid of our old college speakers I decided it was time to upgrade. The basic idea of these is simplicity, one high quality driver backed by a horn. This means you get the speed and performance of a smaller full range driver without sacrificing too much bass. It also means you only buy one driver (instead of 3 usually) and don't have to deal with crossovers.

I built these using Fostex FE126 drivers which were eNabled by Plant10 HiFi. For the wood I used 3/4" baltic birch and cut it using the CNC at my dad's wood shop. By cutting rabbits into the side plates and have every cut CNC accurate the glue-up and assembly was trivial.

I hooked these up to my gainclone amp (which I also built) using banana plug speakers wires built from extension cord.

I'm really impressed with the sound from these! They are great with vocals and acoustic music (Tallest Man on Earth), the sound is very full and so incredibly clear. With deeper bass music (Pretty Lights) they are definitely lacking on the low end. I was most impressed listening to After The Disco (Broken Bells), the album covers a lot of the audio spectrum and these speakers keep up really well. The snare hits are really crisp and clear and every note and accent is heard, nothing gets lost.

I love them!

Tuesday, September 2, 2014

Fresh Updates on The Way

Every so often I get some fresh motivation to start up with sharing life again and I have a lot to update since the last time I posted. Expect some more detailed updates but here is the list of life events since we last talked:

  • Finished my 3D Printer
  • I used my 3D Printer for a bit but haven't used it in a long time now
  • My best friend, Katherine, is now my girl friend. It's great. We live together in Portsmouth
  • I graduated UNH with a BS in Mechanical Engineering
  • I bought a 1979 Austin Mini
  • I took apart my 1979 Austin Mini and will be rebuilding it with a turbo
  • I work as Product Engineer at Turbocam International. I work on developing manufacturing steps and process for making turbocharger compressor wheels.
Talk soon!

Friday, January 13, 2012

Cat5 as Hookup Cable

Latest Thoughts on the Printer(cross post from my post in /r/reprap):

I work in the networking industry and it struck me that cat5 cable might make a pretty interesting option. It is really easy to come by as scrap and really easy to make/terminate with the right tools.
For those not totally familiar: This is the generic ethernet cable seen everywhere. The cable is 8 copper wires (stranded or solid) with 4 pairs that are twisted together, impedance is 50 ohm. Power over ethernet specs require max 57V or .6A on each wire.
My idea would be to put each stepper conductor wire on each pair (4 each). To do this I would make a small PCB with a screw terminal on one end (for stepper wires) and a cable jack on the other. For the electronics ends I would think to make a small board with a jack and 4 male headers to interface with the controller board. I gave a single strand 2.5A at work without any sign of heating up and only .4V. I think it could be really cool and clean and wanted to share the idea and see if anyone had done something similar.
Benefits: Easy to connect/disconnect
Single cable for each axis (organization)
Changing length is easy (with termination tools)
I'll definitely keep you posted on the developments with this

Thursday, January 12, 2012

Updates(of all kinds)

Been a short while since my last update so here is a big update.
Ron Paul came and talked at UNH. Considering that I am interested him as a candidate I thought it smart to get involved and go. Two things to take away: I would definitely get a beer with him, vote for him? Meh. And the dude is very old! Like yeah, he is OLD.

Last night I did a bunch of cooking with my roommates. We made a shit ton of Lemon Rasberry Marmalade and even canned it and some Meringue (using a heat gun to brown the top).

Mendel Max:
I received a huge pile of boxes earlier in the week, two first order catalogs from Igus and Misumi, Steppers, Motor Couplers, Stepper Drivers, PLA and the hot end.
I was a bit dissapointed on the pacakging of the steppers but they seemed to survive fine.
I ordered the rest from Ultimachine who included some extra free filament though I need to determine if it is abs or PLA. The hot end came with the first layer of ceramic all ready set and cured. I got to work putting the connectors on and sure enough I broke the nichrome wire. I had read about how easy it is to do and yet I still did it. Lame. I soldered and crimped everything back together and will test it out but I doubt it will hold. A problem to figure out when I get my power supply. I think the ceramic will help hold it all together.
(Free shit from Igus)

I also installed the drivers on the board which means that I am finally done with the electronics! I only got the 644P working and will try out the 1284 in the future. Still have to figure out what to use for wiring.

Also, I made a VERY last minute decision to drive to Florida tomorrow with some two friends. It is going to be awesome and very inline with my last minute travel decisions of late.

Saturday, January 7, 2012


Once I got the boards all built up it was time to load up the chips. I dont have a programmer so I used the Arduino as ISP method. Bummer is that I needed a resonator to do this unless I wanted to use the internal clock (no thanks). Only resonator I could find at 16mHz was soldered into the Sanguinololu. Time to get out the desoldering tools!
I finally got everything set up and burned the bootloader using the Arduino IDE, put the resonator back in and then tried to install firmware. No dice on either chip. Bummer. Big bummer.
Continuing to take the resonator in and out is plain stupid so I've got a friend at work who is going to let me us his USBtiny and also a resonator. Hopefully by Monday I can get things going a little bit better.
Also, on Monday I should get my steppers, hot end, stepper drivers and couplers! Also, I think I'll be getting some catalogs from Igus and Misumi as I have UPS notifications of shipments from them.
Still no printed parts, I emailed the guy printing them and he seems to be having some trouble with his printer. Fixed now but a delay I'm not stoked on. Nothing I can do but wait (which is so hard to do) and get them when they arrive. I'm convinced that once those show up I will be able to complete the darn thing but I know that's not the case. I still need to source a build platform, get the rods cut and then order any parts I've forgotten about so far.
Project is going well but I am definitely getting antsy.

Wednesday, January 4, 2012

Soldering Time

Finally a project!
Got the electronics today and get started on assembly right away. Did this at work so I could get a bit of help on soldering the FTDI chip which is surface mount and very small. That said, it wasn't too bad at all, not having to cut leads was nice. The rest of it went pretty quickly, after putting together my amp I've gotten pretty good at soldering.

Monday, January 2, 2012

Mendel Ordering Nearly Complete

Just ordered my last big group of parts from Ultimachine. Got a Maker Gear hot end, hobbed bolt, 1 lb of white PLA and 4 Polou drivers. The most expensive single order I have done yet. Mouser order should arrive tomorrow so I will try and start on the soldering soon.
Just realized the printed parts I ordered may not work with my threaded rod as I ordered the x-ends for Igus bushings which also require lead screws and nuts. Crap! Got in touch with the printer and waiting to hear back on if I can change things out.
Hopefully ordering the pulleys tomorrow as well.
Lots of text, and boring updates but I am doing my best to document every step of this progress.

Sunday, January 1, 2012


Happy 2012! Hope everyone had a great new year.
Just a quick update on the printer:
I tapped the holes in the Aluminum rods, just looked at the picture to determine which ones were needed. I like tapping threads though by the 16th hole I was pretty done. The tap worked great and required very little effort though I think a metal file and cutting fluid would have helped a bit.
I located somebody on the IRC that is willing to print some parts for me which is great since the Lulzbot kit is set up for the LMU bushings, not Igus. The person I am buying from is willing to change it up a bit and also has offered some great advice.
I got a cheap organizer at The Home Depot today and put all the hardware away.
Can't wait to get the plastic or the electronic components so I can get going on something. Still need to order some more things, I'm debating a heated build platform but think that I will build one with power resistors.

Saturday, December 31, 2011


Got back to the apartment today and was met with all kinds of boxes and envelopes filled with parts.I tore right into them and here are the beginnings of the printer:

Stuff looks good, I really like the aluminum though I think I was imagining things on a larger scale when ordering. Overall its pretty small but I am okay with that. Still waiting on a couple things. Electronics will come in on Tuesday which will give me something to get started on as I havent ordered the plastic yet.

Thursday, December 29, 2011

Current Mendel Progress

Seems a bit soon for the status update but here is where I am at.
I have ordered most of the parts and followed the BOM from pretty closely holding off on a couple of things until I get my hands on the machine and get an idea about customizations.

Electronics: I opted for the Sanguinololu electronics package, one for the price and two because it was much more feasible to DIY assemble the board than the RAMPS kit. I got my PCB from eBay and all of the electronics from Mouser. There is a pretty extensive BOM available for the board but I also added an ATmega1284 chip to the order so that I can try it is an upgrade to the 644P. In addition I picked up some mechanical switches(end stops) and a thermistor.

Stepper Motors: Per a recommendation from the mendelmax IRC channel I purchased these motors: The price was better than any of the other sites and they do .9 degree stepping. Little worried about the Amp rating being high than recommended value but since the holding torque is so high running with less current shouldn't be terrible.

Extrusions: I ordered these from Misumi as recommended and have only great things to say about the company. I got a call after I ordered curious about the application for my order and they seemed very excited to be part of the project and the recommended supplier. I got a 30% discount on my order, applicable to my next order (pulleys will be ordered!).

Hardware(vitamins):I ordered most of this from McMaster following the BOM and also ordered a M5 tap and tap handle. Pretty excited to finally get a tap as I have always liked using them at the bike shop and they are super useful. The smooth rod and threaded rod is uncut so I will likely have a machine shop cut that for me. In hindsight I wish I had ordered some calipers, I dont have a good set and the should prove useful in the project.

Bearings: Ordered these from VXB but I think I would have been fine just to get them from a skate shop, they were cheap enough though (10 for $10 (shipped)).

Bushings: Not too exciting, ordered from Igus.

Motor Coupler: Purchased two cheap ones on eBay for $5 each.

Still need to order:
Power Supply: eBay
Hot End: Delaying this as it is the single most expensive part ($75) and I want to research more.
Parts Kit: Waiting on lulzbot to get some in stock.
Stepper Drivers: Waiting to see prices at places where I am ordering other things to try and combine shipping.
Pulleys: SDP-SI is out of stock so I will be going with Misumi aluminum timing pulleys once I get my 30% discount credit.
Build Platform: There are so many options out there I am waiting until I get the thing mostly built before planning this piece.
Printing material: Will combine with another order. Still debating PLA vs. ABS.

I'm headed back to the apartment tomorrow so I will update with pictures of everything as it arrives.

3D Printer Madness

Hope you all have had a Merry Christmas. I have certainly enjoyed the time home to relax and not really do anything. Kind of. I dont do well with nothing on my plate so I have started working on a new project: Building a 3D Printer.
For those uniformed a 3D printer (of my style) works by building up plastic layer by layer to great a multidimensional part. The idea is much like a CNC route with a hot glue gun on the end.
I will be getting involved with the Reprap style of printers, ones that are designed to be able to print all of the plastic parts for themselves in a self replicating kind of way. The model I choose is a new design called Mendelmax and boy does it look awesome:
I've just started ordering parts and they should begin to arrive this week. It's going to be a long process of part sourcing, building, calibrating and running but it should be a fun adventure.