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Author Topic: Exotiq Redux 21.5" IPS + Intuos3  (Read 7661 times)
metapharsical
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« on: May 20, 2015, 07:37:06 PM »

First off- HELLO NEW BONGOFISHers !
I've been away for years, but months into my new quest I'm still in awe of the years of contributions I'm discovering!
Such great feats of ingenuity & art & engineering & coding & circuit bending, and did I mention Art?!

Shout-outs:
Dragon's - Wacom Jitter Monitor  was an invaluable tool !!!
Bernard - A great admin of the forum for some time! He's made extraordinarily contributions for years. He knows his electronics hardware!
Aerendraca - A genius contributor/admin with lab tested scientific methods, rigorous trial-and-error, and impeccable designs to say the very least!
Bumhee34 - Another genius and prolific builder, what can I say...? I'm sure you are going to go far in your life and profession!
Woodguy32 - I know I've seen your incredible steampunk creations around the net and I'm a long time fan! I hope you continue new and awesome projects despite your hand injury :-)
Drewid!!! Who shared the original DIY-cintiq! Who selflessly tirelessly maintains this great (spamless!) forum! And who we really aught to thank with our donations, because being a professional artist he probably doesn't make all that much money, hahaha I'm kidding Drew XD Seriously, where's the donation button?!
I'm humbled! It gives me high spirits and really motivates me to share my best ideas with all of you, free open-source is the future!

A quick recap: my previous build lasted a good 5 years before the hacked LED lighting failed (overdriven? overheating?)
Previous Hardware:  
  • Wacom Intuos 3 12x19 model: PTZ-1231w
  • 22"  16:10 Smiley  TN-panel Sad from disassembled monitor made by LG.
  • 31-pin TCON to LVDS cable extended and re-soldered by hand, ughhh... Sad
  • CCFL back lighting swapped with LED strip(made for automotive accent-lights, powered by 12V AC/DC wall adapter) ;cut down some jitters Undecided
  • Shielded by aluminum frame (piece from disassembled monitor), and additional stupid-heavy copper plate under TCON board.
  • Typically some (<4 pixel) jitter near edges. Occasionally worse, inexplicably.

I did not notice until my more recent (more rigorous) experiments... some drift/warp in the wacom pen tracking due to me replacing the Wacom foam spacer with an aluminum support structure. Drew, You cautioned me... Embarrassed
Previous Case:
  • Sleek, sturdy, custom molded fiberglass enclosure. Most labor intensive part Sad
  • 2mm anti-glare-tempered-glass screen-protector epoxy glued to (alum)monitor frame
  • Screen frame and Wacom board joined to plastic-corner-blocks ->epoxy glued to inside of front face of enclosure.
  • Front-to-back of the enclosure joined by 1.5"x1.5"x1.5" slices off an alum U. Everything held good to the front fiberglass face with lots of epoxy and screws ranging #6-32 to #10-32 size holding the LCD & wacom, and front & back enclosure together
  • Aaaaand An Over Engineered, HEAVY DUTY floor standing steel/aluminum articulating arm w/360 tablet rotation

------------------------------------------------------------------------------
New Hardware:
  • Same 12x19 Wacom Intuos3 Tablet.
  • 21.5" panel from disassembled DELL monitor model:S2204M   panel inside: LM215WF3 (S2)(C4)
  • 16:9 aspect ratio Sad
  • 1920x1080 Smiley
  • IPS-panel Grin
  • LED lighting Smiley
  • 82% color gamut Smiley
  • long 30pin TCON-to-LVDS cable, no need to extend FFC's! Grin
  • Scratch-resistant glass <1mm thick, optically bonded to panel Smiley but I dislike the glossiness  Undecided
  • 8mm thickness after stripping
  • no shielding on bare wacom results: NO FALSE CLICKS,  small amount of mostly horizontal jitter after frequency tuning, worsens starting ~9cm/3.5" from left-right edges and to a lesser extent approaching the TCON circuit board.
    Worst is <5 horizontal pixels jitter AVERAGE WACOM JITTER MONITOR results: 28x 9y jitter
  • Note: even on a more jittery tuning, there's practically no visible jitter on the vertical Y-axis, as can be seen in the horizontal line I've drawn all the way up into the corner. After a few refresh rate tunings, I decided to stop checking.
Circles indicate where jitters begin on x-axis.

* scan 64.773.png (33.51 KB. 1899x822 - viewed 331 times.)

Here is the slow hand ruler test with the monitor set to Horizontal scan 67.471 (Vertical refresh rate 59.975Hz)  swapped  H polarity(-) & V polarity(+)

* scan 67.471 Hpolarity Neg.png (28.83 KB. 1899x822 - viewed 291 times.)


I mostly tested aluminum shielding structure and I must say the results are not as good as hoped for.
Here is my experimental setup: I placed everything upside-down on glass to make it easier to add shielding and not disturb the stripped monitor. Note, for testing I also disassembled, thus shortening the pen to improve jitters slightly.

* Test Bench 3.jpg (471.07 KB. 1866x800 - viewed 377 times.)

I've completely shielded the panel up to the damn visible area with aluminum tape, hoping to block energy from the wide signal lines that run along the edges of the panel. This is a picture showing the backside of the bare LCD (backlight removed) with the alum tape (it's inside the edges of the panel ~6mm) perforated for the plastic tabs sticking up from the monitor frame, (looks poorly cut along the far edge, but it's actually black marker around the cut Cool )

* IMG_20150421_193841.jpg (362.15 KB. 1280x960 - viewed 326 times.)

After all that, I wrapped the entire thing in alum foil and grounded everything in a star pattern with one common ground point at the DVI plug for the monitor, I also tried the Wacom USB chassis as ground, checking all these connections with a DC multi-meter to be sure...
Hmmm, it is really difficult to say if all this effort in shielding was worth it. Especially with the risk of electrical shorts.
I still see jitter reach the same peak levels as with no shielding. But subjectively, I definitely notice the oscillation is slower!
I watch the 'Wacom Jitter Monitor' as I move the pen out, over my shielded areas, and the pen signal falls right off a cliff. So my shielding is doing something, eh?
My research into EMI tells me it could get better with a layer of copper, but I feel like it's a waste of money.


Next post: Details of the enclosure...

« Last Edit: July 15, 2015, 04:01:16 AM by metapharsical » Logged
metapharsical
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« Reply #1 on: May 20, 2015, 10:52:04 PM »

Where to start with the case...
Well,
I was happy with the robustness of my Ver1.0 fiberglass case and it still held up after many years, but I'd rather not modify it to try to fit the new screen.

Inspired by Bumhee's laser crafted acrylic & abs case I definitely decided not to mess with fiberglass and molds and sanding and finishing and painting for this build.
This build will essentially be acrylic sheet (3mm ~.125") to make the front and back faces, and 3mm sheet cut into narrow strips to make the edges. You can bet that I'll get more elaborate, and I'll post more details as the build progresses.

We typically start with the attachment of the LCD and the Wacom to the front of the enclosure, but I will get to that later.
First a quick idea for strengthening and sandwiching the structure because it's something other people might generally use:
I plan to construct a frame of 10mm carbon fiber tube around the Wacom foam spacer which will significantly increase the rigidity of the entire structure if I manage to glue and screw it all together real good.

* CF frame.JPG (65.79 KB. 1143x774 - viewed 324 times.)

Square tube would be easier to work with, but I bought round tube for a little cheaper: 96" x 10mm O.D. x 6mm I.D. shipped for less than $40usd
Bonus: The vertical tubes will protrude from the case enough to plug legs into them for a desktop easel stand. Made from .25" metal rod basically just bent into L shapes

* rod stand.jpg (135.67 KB. 929x767 - viewed 261 times.)


Now for the front of the case... I've got some crazy ideas bouncy around my head about mounting the LCD TCON on top the front face rather than underneath.  I could make more better shielding, and the inner frame that holds the panel would be simpler without needing to dodge the FFC's going from the TCON to the panel. But on the downside, the tablet face would have this extra 3-5mm panel on the outside now and that's not so great...EDIT: Decided to mount the TCON inside the enclosure, I like a smooth seamless case better.

* front face 1.jpg (323.19 KB. 1698x854 - viewed 277 times.)

* front face 2.jpg (264.25 KB. 1698x854 - viewed 257 times.)


The material I've got for the front face is 3mm (.125") Mirror Black Acrylic. It's clear acrylic with a mirror (paint?) applied. It is going to make gluing an extra challenge because my experiment bonding the mirror-side to a piece of bare acrylic using 5 minute epoxy, as well as solvent adhesive, was FAIL. The 2-part epoxy I had does not bond well to acrylic or the (painted?) mirror surface. So I will be testing silicone and CA adhesives next.
Here's the monitor sitting on the full sheet of plastic.  Wow, I hope I don't get blinded by the glare  Cheesy

* mirror on gloss .jpg (234.67 KB. 843x899 - viewed 291 times.)


Did I mention I won't be using any additional protective glass for the screen? (OK, I'm open to suggestions for a matte 'screen protector' solution..haha)
Yes, I'm betting the hardened glass that is factory bonded to the LCD is going to hold up against damage to the crystals by the pen for at least a few years with the light punishment I give it.  Oh yeah Also, I got two more of these exact monitors like brand new for $140. So I've got backups Hahaha Cheesy
Though, I plan to build a second one with the other Wacom I have sitting here...But that's another post..

« Last Edit: July 14, 2015, 08:50:54 PM by metapharsical » Logged
metapharsical
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« Reply #2 on: May 20, 2015, 11:20:27 PM »

So at this point I am figuring out the little details of how I'm going to fabricate each piece and how they will ultimately fit together.
I've joined a local makerspace where I have access to saws, drill presses, mills, and a laser cutter. It was a better value than the quotes I got for $150+ just to have my design laser cut. The monthly membership at the DIY shop is $50 a month, +$5/hour for the laser cutter -pretty reasonable I'd say...

I'll be back to answer questions and such, but now I'm on to the doing and making part of the project!
I'll just take this opportunity to share what I have so far- I modeled the Wacom Intuos3 (A3) (12x19) (PTZ-1231w) antennae and controller board in Solidworks.
If it's cool, I could put this up somewhere on the forum for others to use.
PM me

* wacom draft.JPG (91.41 KB. 1452x868 - viewed 286 times.)



« Last Edit: July 15, 2015, 04:02:13 AM by metapharsical » Logged
Aerendraca
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« Reply #3 on: May 21, 2015, 07:13:27 AM »

Thanks for the kind words and welcome back! The original Exotiq was one of the inspirations for me getting into this game so thank you. I can't wait to see how the redux version turns out.

It's always clear to see a seasoned DIY cintiq builder when they start a new build thread, there's no messing about just down with the facts and a presentation of a well laid out plan. It's probably the most crucial thing to emphasize to new builders, think it through carefully before you start.

I love the design you have and the original use of carbon fiber for rigidity, nice touch! I think this is going to be an awesome build so I'll be keeping my eyes in this for sure.

Top tip regarding the acrylic, use Tensol 12 glue if you can get it, its easily the best acrylic glue you'll find, quick cure time, very strong - on a 90degree straight join, once set you'll break the acrylic before the bond.

Another tip, laser cut acrylic edges do not bond as well as saw cut, the heat generated causes the plastics crystal structure to change which in turn causes crazing of the plastic when gluing - the crazing not only looks bad but lessens the integrity in the join.

« Last Edit: May 21, 2015, 07:16:21 AM by Aerendraca » Logged
Drewid
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« Reply #4 on: May 31, 2015, 07:56:03 PM »

Hiya metapharsical, good to see you again, and it's Aerendraca that's doing all the hard work, I'm just hosting stuffs. Smiley
« Last Edit: June 01, 2015, 11:13:55 AM by Drewid » Logged

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rackoony
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« Reply #5 on: June 08, 2015, 05:36:45 PM »

I don't mean to dampen your enthusiasm for working on this project, but I have to ask something. Wouldn't it be easier and cheaper for you to go with the Dell 2209 monitor which had "zero jitter" and do a more thorough LED conversion on it? It seems like you spent more resources, time, and money trying to fix jitter on your newer screen when you already know another screen works perfectly with no jitter issues.
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Aerendraca
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« Reply #6 on: June 09, 2015, 06:58:01 AM »

Since the Dell has no backlight light guide (the clear cast acrylic slab) they're is no means to do an led conversion without obtaining a donor from another screen. This particular screen had a deep recess that houses the ccfl tubes directly behind the panel rather than at the edges, and the light is diffused by a few thin sheets. I'm not sure how metapharsical tested the zero jitter but I can only think it must have been done with the panel placed on the digitizer without the ccfls attached. Also led conversions seem to be much easier to come by within the last year or so, perhaps this is another reason?

That's not to say the conversion on the Dell couldn't be done, I'm sure it can, but I expect it to be a bit of a struggle and I imagine the conversion is unlikely to result in the same viewing angle and colour gamut.
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metapharsical
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« Reply #7 on: June 10, 2015, 10:16:27 PM »

Hello again everybody! Drew and Aerendraca, thanks for your comments!
Not much progress at the moment, I've experimented and found some glues that are going to work well* for bonding all the different materials, and I've decided how things will fit together and what cuts need to be made first.
* CA (superglue) is holding strong to the mirror coating but I don't like how brittle it can be, too much flex and that stuff likes to crack apart. I've got some 'Power Grab' construction adhesive that's showing good adhesion and is more flexible.

@rackoony: No problem, I'm not disheartened by failure. It's a learning experience.
To be specific... That Dell 2209 was an ok screen, and I did attempt a conversion. But Aerendraca nailed it, the donor diffuser and LEDs I pulled from a parts monitor didn't quite fit the oversized frame completely and so terrrible dark spots appeared randomly where the diffuser sagged or didn't get light evenly from the LED strip.
P.S. I think the new monitor is better in every other regard. So I'm actually happy!
I've got more than an 8x10" area that is visibly jitterless, and the edges are still very usable!

As for pen interference... Hell, we know there's large panels that don't cause interference with the Wacom (duh a Cintiq's panel), but hardly any builders have posted ruler drawings or other evidence that convinces me.

It is what it is, and I hear those 'quotes' around "zero jitter" loud and clear... I'm quite skeptical (no personal offence, just my scientific questioning...) of some builder's claims of zero jitter, especially on very large builds. Where I could see a small LCD (for example a thin laptop panel) causing very little jitters... a 21"+ desktop LCD is going to be thicker, and correct me if I'm wrong, emit more EMI simply because of it's large size. Now, It was some years ago that I tested that old screen ontop the tablet, so I'll admit my methods might have been flawed when I reported 'zero-jitter'.(I trashed that screen years ago, sadly I cannot check it more thoroughly)
If your build's got jitters and you've tried tuning and shielding, download 'Lazy Nezumi' , live with it, or ditch it and get a Yiynova or whatever cheaper Cintiq knock-off has the best drivers,
Me... I just like building and hacking stuff to make it 'my own', no matter the cost Wink  
Cheers to all the maniac makers out there!
« Last Edit: July 21, 2015, 10:56:37 PM by metapharsical » Logged
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« Reply #8 on: June 12, 2015, 11:27:37 AM »

A YiYnova... in the long run, I think I will go that way, keeping some of the stuff I placed together for UBiQ.

They - rather, UC-Logic - plan to add tilt sensitivity in the near future, and to place their hotkeys in a "satellite" station that can be docked somewhere where it is comfortable (pretty much the way I went with UBiQ).
 
Still a bit steep for my wallet, but with them I can understand why... they are a small company, with just a fraction of the market it has Wacom, that has to offset an otherwise similar amount of R&D costs.


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« Reply #9 on: June 21, 2015, 04:01:13 AM »

@metapharsical: Heh, well I kind of trusted your claim of 'no jitter' because you'd just come out of building another cintiq and had some experience with it. I almost bought a screen on ebay because of one guy here claiming 'no jitter' and everyone congradulating him for like 10+ posts. It wasn't until after I'd won the auction and I scrolled down and saw that he did indeed have issues lol! I went through a long refunding process to get my money back on that one....ugg.

I did buy a Dell 2209 though. Noticed it does get rather warm near the vents and the back. Hmm...you say the LEDs didn't fit the oversized frame. I'll have to figure that out later I guess. Sorry for thread hijacking btw. I'll post my own build log eventually lol!
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« Reply #10 on: June 21, 2015, 04:36:50 AM »

A little hello to all. @metapharsical: Great stuff as always!  Can't wait to see how it goes.
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metapharsical
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« Reply #11 on: June 24, 2015, 02:52:06 AM »

Procrastination...That's all I'll say.

So, I'll post what I can:
Some pics of my gluing tests where I adhered together bits of
  • Pultruded Carbon Fiber tube
  • 'Black Mirror' Acrylic Sheet (gluing pieces to the painted backside...In the picture, it's what the pieces are sitting on)
  • Clear Acrylic Sheet rectangles
  • UHMW polyethylene (black blocks of plastic)
Using:
  • Loctite Trimethoxysilane 'G02 All Purpose Glue'
  • Loctite Aliphatic Hydrocarbon 'Power Grab All Purpose Interior Construction Adhesive'
  • Loctite Cyanoacrylate 'Plastics Bonding System'
  • Gorilla Cyanoacrylate 'Super Glue Impact-Tough Formula'
  • Loctite Acrylic Epoxy 'Plastic Bonder'

To approximate my final design, I drilled holes in blocks cut from UHMW and sawed them apart to get the half pipe cradles into which I glued the little CF tube bits, and glued that down to the Mirror Backed Acrylic sheet. I also cut little strips of Clear 2mm acrylic sheet and glued them across everything else.

* 1The Lineup.jpg (431.93 KB. 1280x960 - viewed 258 times.)

* 2The Lineup.jpg (384.12 KB. 1280x960 - viewed 246 times.)

Results:
'G02 Glue' -Trimethoxysilane-  fared poorly, all pieces tearing apart from each other without much effort. At point of failure No damage to the materials, It left a flexible skin coating that peeled off both faces of the weld, indicating the glue itself is not very strong, and tearing apart.

* 3 G02 .jpg (381.34 KB. 960x1280 - viewed 258 times.)

'Power Grab' -Aliphatic Hydrocarbon- held together all the different pieces reasonably well. At point of failure No damage to materials, It left a tough gummy glob on only one side of the weld, indicating the glue itself is quite robust.

* 4 Power Grab.jpg (473.82 KB. 960x1280 - viewed 248 times.)

'Plastics Bonding System' -Cyanoacrylate- somekinda 2-part super glue I've never seen, bonded really well to everything (sorry, no pictures). At point of failure the glue's adhesion overpowered the material strength of Carbon Fiber and Mirror Backing, tearing those materials apart rather than the bond breaking for the most part. Still not seeing great adhesion to the black UHMW plastic blocks, it's pretty slippery stuff.
NOTE: DO NOT USE CA GLUE ON ACRYLIC - IT WILL CAUSE SPREADING CHEMICAL REACTION - RUINS SURFACE FINISH

'Super Glue Impact-Tough Formula' -Cyanoacrylate- looks to be thicker than average super glue, well, it's very good for what it is. Held a great bond to everything. At point of failure, tore the Mirror Backing off and stayed stuck to the Clear Acrylic strip , to the Carbon Fiber tube and to the UHMW block.
NOTE: DO NOT USE CA GLUE ON ACRYLIC - IT WILL CAUSE SPREADING CHEMICAL REACTION - RUINS SURFACE FINISH

* 5 CA Gorilla.jpg (357 KB. 960x1280 - viewed 250 times.)

'Plastic Bonder' -Acrylic Epoxy- 2-part epoxy specifically for plastics (definitely an acrylic polymer, doesn't smell like usual ethyl Epoxy compound). Bonded till death. Thick, but after curing time, ANY patch of material touching this stuff went where the glue went  -only giving away after relentlessly prying apart with a screwdriver. WOW!

* 6 Epoxy PlasticBond .jpg (456.65 KB. 1638x960 - viewed 240 times.)

« Last Edit: July 21, 2015, 11:11:03 PM by metapharsical » Logged
Aerendraca
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« Reply #12 on: June 24, 2015, 08:03:10 AM »

Nice scientific method! So the plastic bonder epoxy was the winner. Is it's slightly yellow color going to be a problem or will all the glued parts be hidden away?

What is UMWH? I don't think I've come across this before.
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metapharsical
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« Reply #13 on: July 11, 2015, 06:04:06 AM »

::: EDIT 9/29/15 NEW CONSTRUCTION ! ::: EDIT 9/29/15 NEW CONSTRUCTION ! :::
Back to this build Cheesy  
Thanks for checking out the progress as slow as it is...
More little steps towards completion... I've made a few changes to the design... I decided to incorporate a piece of the Dell monitor to cover the back and to provide a mounting/enclosure for the VGA controller board.
I laser-cut and milling-machined all the pieces for the back half of the case. It's coming together nicely using solvent (methylene chloride) to bond the separate pieces of acrylic together.

A computer model to illustrate the concept:
The rear-half of the case :
Outside:

* case back n.JPG (116.37 KB. 1288x926 - viewed 250 times.)

Inside:

* case back i.jpg (366.89 KB. 1134x739 - viewed 222 times.)

Glued along the back are gently curved walls 17mm high that are cut from an acrylic tube 2" (~5cm) diameter, .125"(~3mm) thick.

* Diagram Round Edge.jpg (334.5 KB. 1400x880 - viewed 241 times.)

Inside the front-half of the case :

* Copper Screen Locks.JPG (372.65 KB. 1558x874 - viewed 248 times.)

Glued to the front are 4mm thick x 17mm tall flat walls, almost rectangle,  except the ends  match the curve of the curved tube edge.
The LCD will be attached to the front face by gluing the tabs of the LCD panel to a thin (.025" 22 gauge) constructed frame of copper sheet with holes that are punched out.  This copper hopefully acts as an RF attenuator not an RF antennae  Undecided


Onwards to progress!

In my test piece you can see what the rounded edge will look like - this is pictured as the LCD side is face-down, rear face-up...

* edge 1.jpg (144.15 KB. 2044x1920 - viewed 240 times.)


Accurately cutting the locations of the holes/edges relative to the front/back faces is very important for this particular design , but it can be said for all these DIY-Cintiq enclosures... you risk destroying your delicate electronics if you squeeze or flex the various layers because of wrong measurements/cuts where your surfaces of contact are made. It's also nice to pick the tablet up Smiley so account for forces that could cause issues with alignment of your components during handling.

Here's my process for fabricating the various pieces so far...

Take a 2" tube of acrylic, put a wooden dowel inside to hold it, mount it in a lathe, cut ends off, round sharp outside edge using corner rounding router bit.

* acrylic tube.jpg (437.79 KB. 1200x900 - viewed 213 times.)


* a tube corner round .jpg (370.72 KB. 1200x900 - viewed 219 times.)


* a tube rounded.jpg (351.39 KB. 1200x900 - viewed 212 times.)

Setup tube over wooden dowel in laser cutter. Take two long cuts to make strips from tube.

* Laser tube setup.jpg (393.28 KB. 1920x1440 - viewed 217 times.)

Setup wood dowel as a fixture in milling machine and tape acrylic piece to wood dowel using double-sided carpet tape to hold it down (this stuff holds VERY STRONG, but just to be sure I also put some clamps on it too)

* curve edge mill setup.jpg (399.58 KB. 1920x1440 - viewed 228 times.)

Mill long edges straight and plunge a 10mm end mill bit to make cross-holes for carbon fiber tube

* curve cross hole mill setup.jpg (359.9 KB. 1920x1440 - viewed 222 times.)

Whoo! that was a lot of work just to make two edges Cheesy damn they look sweet though!
Ok, so then I lasered the flat pieces which get attached to the curved pieces and will be the frame around the Dell monitor back piece. I didn't get any pictures of that process, but here's one of the pieces in the mill setup to cut the 50° angle so that it will mate to the curved edge.

* Chamfer Edge .jpg (418.96 KB. 2560x1920 - viewed 220 times.)

I used this fly-cutter with a custom made cutting bit which I made myself to get the exact angle I needed on the edge:

* chamfer tool.jpg (160.79 KB. 1200x900 - viewed 221 times.)

I also put some work into making a special jig to hold the curved edge while it gets bonded to the flat pieces:

* curve fixture.jpg (258.89 KB. 1200x1600 - viewed 224 times.)

Then it was time to bond the separate pieces together. I wish I had gotten more pictures of this, it was pretty hilarious how many clamps I used to hold everything together while the bond cured along the curved edge   Cheesy
Here's the progress so far:

* bonding back case.jpg (332.09 KB. 1812x1788 - viewed 263 times.)

Kinda hard to tell what your looking at because it's all clear acrylic except for the black ABS Dell monitor piece and it's all sitting on top of a glass table on top of a another table  Grin . But I've got all the acrylic pieces bonded together.

Next step is strengthening the frame. I designed and milled these little blocks to go along the edges.  I just have to saw these apart and glue them in and the back frame will be complete!

* anchor block nest.jpg (360.71 KB. 900x1200 - viewed 234 times.)


P.S. @Aerendraca :  Yes, the 'Plastic Bonder' Epoxy did everything I needed, and it's yellow color won't be a problem, those parts won't be visible, AND I won't be gluing any of the laser-cut edges Cheesy

Ultra High Molecular Weight Polyethylene (UHMW); I've came across UHMW at work while I was machining parts for conveyor assemblies. It's a very low friction, durable and machinable plastic. I planned to cut the stiffener blocks that I could not make from acrylic sheets, but it turns out UHMW will not work for this. It's mostly used to protect sliding surfaces, it doesn't glue well (read up on it, and it did the worst in my tests), and thermally expands as bad as wood.
EDIT:
Polyphenylsulfone is the much better alternative I found, and we happened to have some throw-away chunks of it at the company I work for! This stuff actually bonds beautifully to the acrylic using the methylene chloride solvent glue I already have! This is what the grey stiffener blocks are made from now.

« Last Edit: September 29, 2015, 07:15:13 PM by metapharsical » Logged
Aerendraca
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« Reply #14 on: July 13, 2015, 08:21:12 AM »

Very very nice!! How did you get such a lovely curve to the acrylic? I really can't wait to see how you progress with this build, looks like it's going to be awesome.
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