Prime 29 Diffuser Build - Using QRDude - Page 2

collo · 22nd December 2009, 08:52 AM

Quote:

Originally Posted by Lonely Raven

... I'm wondering what you diffusion gurus think of something like this.

Collo, any suggestions on how to model something like this in QRDude?

It looks like it's built of 3 * 3 modules set at random heights. As luck would have it, I've been working on latest mod for QRDude (due out in a day or so). The attached shot shows a depth-optimised 2D inverse N3 that is quite like the pattern you have, but not exactly equal to it. Not quite sure what your's is, but probably not a proper QRD - maybe PRD..

terry j · 22nd December 2009, 10:57 AM

Quote:

Originally Posted by Lonely Raven

I'm still making some progress on this. Been busy with family stuff for the holidays. I have some photos I'll download once I get my camera battery charged. But for now, I'm wondering what you diffusion gurus think of something like this.

lupo gave a few thoughts on this design in another thread..

2 ch listening room, aiming for best possible.

back then we were not 'into' 2d qrds so lupo thought it may be based on prd math. now we have 'the best qrd calc on the planet' (tm) it would not be hard to see if it is more prd or 2d qrd based.

Let us know how the last bits of your grid fit in. I gave up on mine, it just got tighter and tighter. Mine was much deeper than yours tho, that could have had something to do with it.

edit. I see collo already looked at the prd/qrd question. I should read a bit more carefully.

Lonely Raven · 22nd December 2009, 07:11 PM

Well, if we can work out a plan to help me design something like this "golden horn", I'll try to build one up. It doesn't have to be an exact clone of the Swedish one, I just like the idea of nested design, like that one RPG fractal, but in a 2D format.

criticaldistance · 22nd December 2009, 07:55 PM

sorry for going off topic, but, awesome cats! are those bengals?

Lonely Raven · 22nd December 2009, 08:36 PM

Quote:

Originally Posted by criticaldistance

sorry for going off topic, but, awesome cats! are those bengals?

Yes, we have two Bengals and two Strays we took in. Plus our puppy is a Leonberger (which are probably more common in your parts).

collo · 22nd December 2009, 09:46 PM

from the manufacturer ...

Golden Horn is unique among the diffusers in the world market with its shape and flexibility. Crossover frequency is 2000Hz and diffuses into its basic design from 800 - 16000Hz. Diffusion up to 2000Hz is created by 40, 80 and 120mm high diffusorklossar to a number of 216st/m2.Diffusionen over 2000Hz creation of 9 squares each separated by 1mm thick partition walls positioned on top of each diffusorkloss. In this way, distributed incident sound i1944st fack/m2.

Diffuses into the field: 800-16000Hz
Width: 550mm
Length: 550mm
Depth: 128mm
Performance: Plastic Flame

You could use this info to reverse engineer using 2D QRDs if you wanted to.

N3's wont give you as good diffusion as N7's will though. For the stagger pattern depths, use QRDude to design an "outer" 2D diffuser of whatever order you need to get your required area. Model the outer diffuser without fins.

Lonely Raven · 11th January 2010, 06:13 AM

Update on the N29 diffusers.

They are *bust* for now.

I spent about six hours on the first one today, hoping to finish up the "grid" so I can focus on making a better jig for the "tiles". I got down to the last 10 fins in the grid, and they just wouldn't fit. It's not that they were too tight, as I found earlier on, because I've introduced a little extra slop in my cuts. The problem comes from the "key" in the jig I made:

The problem lies in that I'm cutting 5 pieces at a time, sometimes more. And it turns out, the key is deflecting slightly. So the fins closes to the backbone of the jig are more consistent than the ones towards the other end of the key. They key deflects a little, and the 5th or 6th fins slots are slightly wider....and wider...and wider.

On a Prime 11, this wouldn't be a big deal as the incremental offset is minimal only 11 slots in. But when you get to the last 25-28, it's off by enough that it looks like a part for a completely different puzzle.

SO! This leaves me to do one of two things. Either scrap this project and just start churning out some 2' X 2' Prime 11 with 2.185" tiles, or I build a better, more stable jig and start an all new pair of prime 29.

I'm very frustrated in this...I should have seen this coming. Every issue I resolved only made me realize another issue. But this is what I get for attempting such a grand build...I feel like I'm building a space shuttle with Henry Ford's production line and tools. Either I need to create better tools, or reel in the project to something a little more realistic.

All that said, I've already got a design in my head for a better jig that will be several-fold more accurate. I'm just not sure I want to run out and buy another $60 of MDF and start all over for a show off project.

collo · 11th January 2010, 06:36 AM

Bummer!

However as my previous employer liked to say - it's another opportunity for excellence!

Seriously though, we all appreciate you taking the lead on this.

I've been thinking about how I would build one, and had decided that I would like to try gluing from the back using silicone - would ensure a complete seal as well as gluing. Some masking tape from the front would hold the floor plates during drying.

This would also allow some gap-filling opportunities.
You might be able to recut the problem slots and use silicone to take care of the extra slop, thus salvaging the project.
A new jig to stop the errors adding could also be worth developing. Completely understand if you've had a gutful though...

A9X · 11th January 2010, 07:04 AM

It is a bummer and I'm sorry it didn't work out too well for you. But take heart that some of the woodwork challenged (aka me) can learn from your experiences as we plan out our diffusors and maybe avoid the same problems.

Lonely Raven · 11th January 2010, 07:53 AM

Thanks guys.

I'm going to forge ahead with the project, though I'm still undecided if I'm going to be so elaborate as doing an N-29. I knew from the beginning it was overkill, but for me, the experience I gain from the journey is worth it.

With all I've learned attempting the N-29, a big N-11 would be a cake walk.

My recommendations to anyone else looking to build one of these 2D diffusers, is to KISS.

If I were doing this for a studio, I'd build big, solid, easy, and efficient. More sound treatment tends to work better than a few *really* good ones IMHO.

All that said; I'm going to start building up a better set of Jigs this week. Even if I don't do a Prime-29, a really sharp set of super accurate jigs will allow me to build these for local guys with speed and accuracy that only experience would have brought me. And I'm seriously considering building a fleet of 2' X 2' 2D diffusers for my guitar room and future two channel listening area. So the effort isn't at all a loss, just a lesson.

More to come as I make progress on the jigs. I'm sure once I get this sorted out I'll be churning these out like nothing.

Lonely Raven · 12th January 2010, 06:48 AM

And now I enter the space age!!

OK, I'm back on track with the prime 29! A new jig has been built, and I cut my first 17 fins. So that's about 80 fins of trash, and 17 fins of space age accuracy! No joke, with this new jig, all 17 fins are within 1/16th, maybe less, from the first slot to the last slot. Now the slot cuts are so bang on, that the pieces actually fit a little loose due to not pulling on each other (e.g. slots being off caused tension from fin to fin that is now gone!).

I made a box sled using my new Kreg pocket hole tool. (awesome tool by the way!) And I used a 1/8" aluminum bar I picked up at the hardware store as my "key". 1/8" MDF is a little thinner then 1/8", so I sanded the aluminum down a hair. With this jig setup, I can setup slots for 1", 2", and 3" spacing between slots simply by cutting a new slot and moving the aluminum bar!

Supa-accurate!

First 17 pieces fit together like they were CNC machined!

Just for grins, I tried cutting 18 fins all at once, and it was no problem. Even with that many pieces, there was no deflection in the aluminum bar...though it was a huge pain in the arse to pull them all up off the bar, move them all over one slot, cut and repeat. So I've settled on cutting six pieces at a time.

So, now that this is done, and bang on accurate, I'm going to have to revise my tile cutting jig as well. I have to try and come up with something that will be accurate to 1/32 of an inch, and be adjustable so I can set it up for 1" tiles, 2 1/8", whatever. I'll work on that later. For now, I need to cut out over 100 more fins, which means I need a few more full panels of 1/8" MDF.

I'm very excited about this again! If I can get the tile jig to work out as accurately as the fin jig, then I can start considering 1/8" plywood with nice hardwood faces, though that's 3X the cost of MDF of the same thickness.

terry j · 12th January 2010, 07:01 AM

understand the al business, but what keeps the entire box from moving? Hope that made sense..I presume there are guides under the box that slides in the slots I can see...or is the box fixed to the 'square' I see.

collo · 12th January 2010, 07:08 AM

Congratulations!

I was thinking that using the one key position and moving the fins for each cut would lead to a cumulative error, but you have shown this not to be the case with your new jig. Obviously having a tight fit on the key is the secret.

I think we might have to start referring to you as the jigmeister...

Lonely Raven · 12th January 2010, 07:39 AM

Quote:

Originally Posted by terry j

understand the al business, but what keeps the entire box from moving? Hope that made sense..I presume there are guides under the box that slides in the slots I can see...or is the box fixed to the 'square' I see.

Yes, the box is screwed to the Miter, and the miter is what slides through those channels in the cast iron table. At this point, I pretty much consider the jig and miter a single tool. This miter will be married to the jig, and I will simply buy another one. Once I get all the slots worked out (I'm afraid to make any changes yet! LOL), I'll probably epoxy the jig to the miter so there is no chance for drift. Part of my problem with the old jig is that the slightest changes in anything threw it all off. This should be pretty repeatable.

Quote:

Originally Posted by collo

Congratulations!

I was thinking that using the one key position and moving the fins for each cut would lead to a cumulative error, but you have shown this not to be the case with your new jig. Obviously having a tight fit on the key is the secret.

I think we might have to start referring to you as the jigmeister...

Yes, the key actually goes completely through the bottom panel. So it's held in place at the ends of the jig, and all across the bottom. I think the miter has more "play" in it than the aluminum key.

I have an assembly jig already designed in my head to help me speed up gluing the tiles in...but I'm not sure I'm going to build it for the prime 29 unless I build more than two units. It would take me so long to build the assembly jig, that I might as well just chug through placing each tile by hand for these bad boys.

I just really need to get a good idea for the tile cutting jig. There has to be a good way to quickly and accurately cut 1682 tiles....

Waiting for Fullness.

If this continues to work well, I've already got plans for my next batch of 2D diffusers. They will be 2' X 2', N11, and 6" deep. I'd like to make a fleet of them for my guitar room. They should be hugely easier than the Prime 29.

PaulP · 12th January 2010, 02:19 PM

Nice jig

but - get a block of wood behind there. Your thumb will thank you.

Paul P

Lonely Raven · 12th January 2010, 02:59 PM

Quote:

Originally Posted by PaulP

Nice jig

but - get a block of wood behind there. Your thumb will thank you.

Paul P

Thanks, I was thinking about that, but many years of woodworking has me one step ahead of you.

Left hand rests on the miter and fence, right hand rests on the right side of the key on the fence (the key is pretty tall). I found it would be very difficult for me to put my hand in the danger zone between these two points and still use the jig comfortably. I'd have to go out of my way to hold it differently and unsafely. And once I've got my physical motion set, it's unlikely I'll change it. I've also added an "Anti-fatigue Matt" in front of the table saw, for better traction and for my knees (since I'm going to be here a while!). I think the only way I could make myself safer at this point, is if I get a gas mask with a sealed visor to keep the dust out from behind my glasses and out of my hair! LOL

I saw in the paper that Menards is having a sale on 1/8" MDF. Whole sheets for about $6, which is half what I usually pay for it. I think I'm going to stock up if I can figure out how to cut it while I'm there to fit it in my wagon.

Lonely Raven · 19th January 2010, 05:44 AM

I got a little work done over the weekend...well, pretty much all done today.

Before I go on with my usual photos and verbose descriptions, a helpful tip:

Don't go changing settings or methods mid stream. I wound up throwing out 8 fins and dealing with a little bit of waviness in my fins due to deciding to slot 8 fins at a time with the new jig. Plus, I removed my setup from the table saw to I could build a small sub box for my fiance's car yesterday. So two changes to the setup meant I ruined a few fins till I got my settings back on track.

So, if you're going to build it, make sure you've got enough wood, and do each stage in ONE go. Or, if it takes a few days, don't change anything till your done with all the cuts. Then go to the next step or next project!

OK, back on track. I'm tired, so I'll try and be brief and let the photos do most of the talkin.

OK, stack of fins cut. This is about 1/3 what I cut today.

Another photo of the new jig:

And chop chop chop, I make lots-o-fins. The one that's missing I actually had to break out. It was just slightly off by enough that it threw the whole unit off. I snapped it out, and made a replacement. I think I eventually had to do this for 3 fins due to changing setups in mid stream.

Ohhh, cosmic and artsy!

OK, new tile cutting jig. I wasn't very creative here. It's just a variant of the fin cutting jig. The MDF in the jig is what I'm about to cut. It's a cutoff from one of the fins. The "C" Clamp is used in place of my finger. What I mean is that it's there to hold the 1/8" MDF piece down while I run the jig forward into the blade, and back to me. The round "nose" on the C Clamp is just the right shape for the job. I can run the whole jig with one hand, and that hand never leaves the miter during the actual cutting process.

So basically I take any scraps I may have that are a hair over 1" X 1" or better, then I square off the end in the jig so I have a nice sharp working edge, then I push it under the nose of the C Clamp, push the jig into and back from the blade, and I have a 1" deep by *whatever* the scrap is wide. Turn the cut off 90 degrees and run it through the same process, and now I've got 1" X 1" tiles.

Technically they are about 1.084" X 1.084" give or take .01
I really wanted to be more accurate than that, but I'd need a more accurate miter and some T-slots and other stuff I just didn't feel like spending money on. This should do fine. A couple hundred turned out in about 45 minutes. Only about 1300 more to go!!

Lonely Raven · 19th January 2010, 05:51 AM

Getting the beast ready for "tiling". It's about 34" X 34" X 3.5", give or take about 1/8" at the worst.

My tiling jig for these two beasts I'm putting together. Basically I took some 3/4" (nominal) paneling scraps I had left over from the 21" sub-woofer build, and cut them into 3/4" X 3/4" X "Well depth". Then I numbered each block with it's "well depth", and I'll drop it into the slot, press the tile in, then glue from behind. Here is the outer row I just did before sitting down at the computer.

I'm using silicone for the outer tiles to make sure they are in solidly. But there is no way I could use silicone for the rest of the diffuser, unless I made the diffuser a max-depth of 2"...there is no way to get the silicone nozzle down in each well....unless I just bulk dumped silicone back there...but that would be sloppy and expensive. The tiles in place, just before silicone in.

For the rest of the device, I'll have to use a long paint brush and wood glue. I've not really thought out how I'm going to get the little "well depth" wood blocks out of the enclosed wells. I may have to pick the whole device up after each row and sweep the blocks out from under it. What a PITA.

The next ones I'm doing will totally be Prime 11.

Lupo · 19th January 2010, 10:24 AM

Looking great!

It's gorgeous as is too, without the wells.

collo · 19th January 2010, 11:03 AM

Those photos are fantastic.!

Nice work on the jigs too.

You could have the glue underneath if you build upside-down, cutting your guage blocks for well depths rather than (block height - plate thickness)

If there's any mod to QRDude that would make the build go any easier, just sing out...

Lonely Raven · 19th January 2010, 01:31 PM

Quote:

Originally Posted by collo

Those photos are fantastic.!

Nice work on the jigs too.

You could have the glue underneath if you build upside-down, cutting your guage blocks for well depths rather than (block height - plate thickness)

If there's any mod to QRDude that would make the build go any easier, just sing out...

I am doing Well Depths on this build. You're seeing the unit face down in this photo, and each block is cut to well depth. So the face of the tiles should be at well depth within 1/16" (the blocks are accurate to 1/32", but the whole unit has a little flex to it).

I can't imagine how QRDude could be more useful at this point. It really does everything I need to conceptualize and calculate. I really think the only thing that could make it easier at this point, is if I could put in dimensions and have it figure out an optimized QRD for X by X dimensions with a couple minimum data points.

Oh, I do wonder if there is a calculation for the time delay introduced by the QRDs. I was thinking about something Ron Sauro and SAC said about working with time above the critical frequency, and I'm wondering how to figure out the time scattering effect of a particular QRD. I'll probably have to call those guys on that and see what they say.

All in all, QRDude is what got me to this point. Well, that and about $120 in MDF.

PaulP · 19th January 2010, 02:53 PM

Quote:

Originally Posted by Lonely Raven

That's crazy

Paul P

Lonely Raven · 19th January 2010, 02:55 PM

I guess I have the skills to make one of those "space couplers", huh?

PaulP · 19th January 2010, 06:32 PM

Quote:

Originally Posted by Lonely Raven

I guess I have the skills to make one of those "space couplers", huh?

I was thinking the same thing !

Paul P

PS. I'm looking forward to hearing from you what this thing sounds like when you're in front of it.

Lonely Raven · 19th January 2010, 06:41 PM

Quote:

Originally Posted by PaulP

I was thinking the same thing !

Paul P

PS. I'm looking forward to hearing from you what this thing sounds like when you're in front of it.

Even right now I can hear it effecting my voice. But not in a good way. It will be fun to hear my voice with all the tiles in. In fact, one of the first things I'm going to do once I get both of these assembled, is bring them into my little office/guitar area and play around with a Zoom H2 and some guitars and see if I can capture how they effect the immediate area. (effect? affect? I never remember which is correct)

As much of a PITA as these are to build, I'm really enjoying how they are coming along. I'm sure everyone realizes I didn't *need* a pair of N29 when a bunch of much more simple N11 would do. This is really one of those "Because I can" moments.

Schaap · 19th January 2010, 07:20 PM

Great

work! With the tiles in it, it will weight a lot. Be careful when moving around with it

19th January 2010, 07:20 PM	#56
Schaap Gear addict Join Date: Sep 2004 Location: Netherlands Posts: 365	Great work! With the tiles in it, it will weight a lot. Be careful when moving around with it __________________ "Poetry and music" http://tinyurl.com/cmtwkp

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22nd December 2009, 07:11 PM	#33
Lonely Raven Gear maniac Join Date: Nov 2009 Location: Bolingbrook, IL Posts: 222	Well, if we can work out a plan to help me design something like this "golden horn", I'll try to build one up. It doesn't have to be an exact clone of the Swedish one, I just like the idea of nested design, like that one RPG fractal, but in a 2D format.

22nd December 2009, 07:55 PM	#34
criticaldistance Gear nut Join Date: Apr 2008 Location: amsterdam Posts: 91	sorry for going off topic, but, awesome cats! are those bengals?

22nd December 2009, 09:46 PM	#36
collo Gear maniac Join Date: Aug 2009 Location: Newcastle, Australia Posts: 187	from the manufacturer ... Golden Horn is unique among the diffusers in the world market with its shape and flexibility. Crossover frequency is 2000Hz and diffuses into its basic design from 800 - 16000Hz. Diffusion up to 2000Hz is created by 40, 80 and 120mm high diffusorklossar to a number of 216st/m2.Diffusionen over 2000Hz creation of 9 squares each separated by 1mm thick partition walls positioned on top of each diffusorkloss. In this way, distributed incident sound i1944st fack/m2. Diffuses into the field: 800-16000Hz Width: 550mm Length: 550mm Depth: 128mm Performance: Plastic Flame You could use this info to reverse engineer using 2D QRDs if you wanted to. N3's wont give you as good diffusion as N7's will though. For the stagger pattern depths, use QRDude to design an "outer" 2D diffuser of whatever order you need to get your required area. Model the outer diffuser without fins.

11th January 2010, 06:13 AM	#37
Lonely Raven Gear maniac Join Date: Nov 2009 Location: Bolingbrook, IL Posts: 222	Update on the N29 diffusers. They are bust for now. I spent about six hours on the first one today, hoping to finish up the "grid" so I can focus on making a better jig for the "tiles". I got down to the last 10 fins in the grid, and they just wouldn't fit. It's not that they were too tight, as I found earlier on, because I've introduced a little extra slop in my cuts. The problem comes from the "key" in the jig I made: The problem lies in that I'm cutting 5 pieces at a time, sometimes more. And it turns out, the key is deflecting slightly. So the fins closes to the backbone of the jig are more consistent than the ones towards the other end of the key. They key deflects a little, and the 5th or 6th fins slots are slightly wider....and wider...and wider. On a Prime 11, this wouldn't be a big deal as the incremental offset is minimal only 11 slots in. But when you get to the last 25-28, it's off by enough that it looks like a part for a completely different puzzle. SO! This leaves me to do one of two things. Either scrap this project and just start churning out some 2' X 2' Prime 11 with 2.185" tiles, or I build a better, more stable jig and start an all new pair of prime 29. I'm very frustrated in this...I should have seen this coming. Every issue I resolved only made me realize another issue. But this is what I get for attempting such a grand build...I feel like I'm building a space shuttle with Henry Ford's production line and tools. Either I need to create better tools, or reel in the project to something a little more realistic. All that said, I've already got a design in my head for a better jig that will be several-fold more accurate. I'm just not sure I want to run out and buy another $60 of MDF and start all over for a show off project.

11th January 2010, 06:36 AM	#38
collo Gear maniac Join Date: Aug 2009 Location: Newcastle, Australia Posts: 187	Bummer! However as my previous employer liked to say - it's another opportunity for excellence! Seriously though, we all appreciate you taking the lead on this. I've been thinking about how I would build one, and had decided that I would like to try gluing from the back using silicone - would ensure a complete seal as well as gluing. Some masking tape from the front would hold the floor plates during drying. This would also allow some gap-filling opportunities. You might be able to recut the problem slots and use silicone to take care of the extra slop, thus salvaging the project. A new jig to stop the errors adding could also be worth developing. Completely understand if you've had a gutful though...

11th January 2010, 07:04 AM	#39
A9X Gear interested Join Date: Oct 2009 Posts: 4	It is a bummer and I'm sorry it didn't work out too well for you. But take heart that some of the woodwork challenged (aka me) can learn from your experiences as we plan out our diffusors and maybe avoid the same problems.

11th January 2010, 07:53 AM	#40
Lonely Raven Gear maniac Join Date: Nov 2009 Location: Bolingbrook, IL Posts: 222	Thanks guys. I'm going to forge ahead with the project, though I'm still undecided if I'm going to be so elaborate as doing an N-29. I knew from the beginning it was overkill, but for me, the experience I gain from the journey is worth it. With all I've learned attempting the N-29, a big N-11 would be a cake walk. My recommendations to anyone else looking to build one of these 2D diffusers, is to KISS. If I were doing this for a studio, I'd build big, solid, easy, and efficient. More sound treatment tends to work better than a few really good ones IMHO. All that said; I'm going to start building up a better set of Jigs this week. Even if I don't do a Prime-29, a really sharp set of super accurate jigs will allow me to build these for local guys with speed and accuracy that only experience would have brought me. And I'm seriously considering building a fleet of 2' X 2' 2D diffusers for my guitar room and future two channel listening area. So the effort isn't at all a loss, just a lesson. More to come as I make progress on the jigs. I'm sure once I get this sorted out I'll be churning these out like nothing.

12th January 2010, 06:48 AM	#41
Lonely Raven Gear maniac Join Date: Nov 2009 Location: Bolingbrook, IL Posts: 222	And now I enter the space age!! OK, I'm back on track with the prime 29! A new jig has been built, and I cut my first 17 fins. So that's about 80 fins of trash, and 17 fins of space age accuracy! No joke, with this new jig, all 17 fins are within 1/16th, maybe less, from the first slot to the last slot. Now the slot cuts are so bang on, that the pieces actually fit a little loose due to not pulling on each other (e.g. slots being off caused tension from fin to fin that is now gone!). I made a box sled using my new Kreg pocket hole tool. (awesome tool by the way!) And I used a 1/8" aluminum bar I picked up at the hardware store as my "key". 1/8" MDF is a little thinner then 1/8", so I sanded the aluminum down a hair. With this jig setup, I can setup slots for 1", 2", and 3" spacing between slots simply by cutting a new slot and moving the aluminum bar! Supa-accurate! First 17 pieces fit together like they were CNC machined! Just for grins, I tried cutting 18 fins all at once, and it was no problem. Even with that many pieces, there was no deflection in the aluminum bar...though it was a huge pain in the arse to pull them all up off the bar, move them all over one slot, cut and repeat. So I've settled on cutting six pieces at a time. So, now that this is done, and bang on accurate, I'm going to have to revise my tile cutting jig as well. I have to try and come up with something that will be accurate to 1/32 of an inch, and be adjustable so I can set it up for 1" tiles, 2 1/8", whatever. I'll work on that later. For now, I need to cut out over 100 more fins, which means I need a few more full panels of 1/8" MDF. I'm very excited about this again! If I can get the tile jig to work out as accurately as the fin jig, then I can start considering 1/8" plywood with nice hardwood faces, though that's 3X the cost of MDF of the same thickness.

12th January 2010, 07:01 AM	#42
terry j Gear maniac Join Date: Jul 2009 Posts: 258	understand the al business, but what keeps the entire box from moving? Hope that made sense..I presume there are guides under the box that slides in the slots I can see...or is the box fixed to the 'square' I see.

12th January 2010, 07:08 AM	#43
collo Gear maniac Join Date: Aug 2009 Location: Newcastle, Australia Posts: 187	Congratulations! I was thinking that using the one key position and moving the fins for each cut would lead to a cumulative error, but you have shown this not to be the case with your new jig. Obviously having a tight fit on the key is the secret. I think we might have to start referring to you as the jigmeister...

12th January 2010, 02:19 PM	#45
PaulP Lives for gear Join Date: Sep 2009 Posts: 634	Nice jig but - get a block of wood behind there. Your thumb will thank you. Paul P

19th January 2010, 05:44 AM	#47
Lonely Raven Gear maniac Join Date: Nov 2009 Location: Bolingbrook, IL Posts: 222	I got a little work done over the weekend...well, pretty much all done today. Before I go on with my usual photos and verbose descriptions, a helpful tip: Don't go changing settings or methods mid stream. I wound up throwing out 8 fins and dealing with a little bit of waviness in my fins due to deciding to slot 8 fins at a time with the new jig. Plus, I removed my setup from the table saw to I could build a small sub box for my fiance's car yesterday. So two changes to the setup meant I ruined a few fins till I got my settings back on track. So, if you're going to build it, make sure you've got enough wood, and do each stage in ONE go. Or, if it takes a few days, don't change anything till your done with all the cuts. Then go to the next step or next project! OK, back on track. I'm tired, so I'll try and be brief and let the photos do most of the talkin. OK, stack of fins cut. This is about 1/3 what I cut today. Another photo of the new jig: And chop chop chop, I make lots-o-fins. The one that's missing I actually had to break out. It was just slightly off by enough that it threw the whole unit off. I snapped it out, and made a replacement. I think I eventually had to do this for 3 fins due to changing setups in mid stream. Ohhh, cosmic and artsy! OK, new tile cutting jig. I wasn't very creative here. It's just a variant of the fin cutting jig. The MDF in the jig is what I'm about to cut. It's a cutoff from one of the fins. The "C" Clamp is used in place of my finger. What I mean is that it's there to hold the 1/8" MDF piece down while I run the jig forward into the blade, and back to me. The round "nose" on the C Clamp is just the right shape for the job. I can run the whole jig with one hand, and that hand never leaves the miter during the actual cutting process. So basically I take any scraps I may have that are a hair over 1" X 1" or better, then I square off the end in the jig so I have a nice sharp working edge, then I push it under the nose of the C Clamp, push the jig into and back from the blade, and I have a 1" deep by whatever the scrap is wide. Turn the cut off 90 degrees and run it through the same process, and now I've got 1" X 1" tiles. Technically they are about 1.084" X 1.084" give or take .01 I really wanted to be more accurate than that, but I'd need a more accurate miter and some T-slots and other stuff I just didn't feel like spending money on. This should do fine. A couple hundred turned out in about 45 minutes. Only about 1300 more to go!!

19th January 2010, 05:51 AM	#48
Lonely Raven Gear maniac Join Date: Nov 2009 Location: Bolingbrook, IL Posts: 222	Getting the beast ready for "tiling". It's about 34" X 34" X 3.5", give or take about 1/8" at the worst. My tiling jig for these two beasts I'm putting together. Basically I took some 3/4" (nominal) paneling scraps I had left over from the 21" sub-woofer build, and cut them into 3/4" X 3/4" X "Well depth". Then I numbered each block with it's "well depth", and I'll drop it into the slot, press the tile in, then glue from behind. Here is the outer row I just did before sitting down at the computer. I'm using silicone for the outer tiles to make sure they are in solidly. But there is no way I could use silicone for the rest of the diffuser, unless I made the diffuser a max-depth of 2"...there is no way to get the silicone nozzle down in each well....unless I just bulk dumped silicone back there...but that would be sloppy and expensive. The tiles in place, just before silicone in. For the rest of the device, I'll have to use a long paint brush and wood glue. I've not really thought out how I'm going to get the little "well depth" wood blocks out of the enclosed wells. I may have to pick the whole device up after each row and sweep the blocks out from under it. What a PITA. The next ones I'm doing will totally be Prime 11.

19th January 2010, 10:24 AM	#49
Lupo Lives for gear Join Date: Aug 2005 Location: Norway Posts: 1,170	Looking great! It's gorgeous as is too, without the wells.

19th January 2010, 11:03 AM	#50
collo Gear maniac Join Date: Aug 2009 Location: Newcastle, Australia Posts: 187	Those photos are fantastic.! Nice work on the jigs too. You could have the glue underneath if you build upside-down, cutting your guage blocks for well depths rather than (block height - plate thickness) If there's any mod to QRDude that would make the build go any easier, just sing out...

19th January 2010, 02:55 PM	#53
Lonely Raven Gear maniac Join Date: Nov 2009 Location: Bolingbrook, IL Posts: 222	I guess I have the skills to make one of those "space couplers", huh?