DIY Curved Screen with structural extruded aluminum metal framing - Page 2

No, I've not "given up" this DIY project, other normal life distractions got in the way for a while.
Plus, like others here have found out, the temp primer drywall'd wall screen does a decent enough job so we've been watching that and the "pressure" to finish the "real" screen is less.
Since I want to carpet the HT room over xmas vacation all these little/final DIY projects now have to get done.

Therefore, finally made some progress over Thanksgiving weekend (Sat afternoon and Sunday).

Wood frame making that will become curved and used for attaching DW laminate & screen black border too.
I used base board molding from HomeDepot, it was 1/2" thick x 4" wide, mostly flat with slight router shape on the top edge.
Used table saw to get rid of that for a 3 1/2" wide piece.
The whole wood frame will be mostly overhang the alum frame by 1/4" on the inside and the rest overhang on the outside.

Measure/cut confirm before attaching together.


Wood frame together, used dual corner braces to keep the frame "flat/in plane to itself" when it becomes curved:
(that's my theory at least...)




Getting ready to attach the wood frame to the alum frame.
The alum frame is blocked off ground at the 4 corners and center.


Corner shot and misc hardware to be used:


After debating/different design concepts for the end supports, I decided to use 4 x 4 (really 3 1/2 x 3 1/4) Cedar post. I picked a very tight grain running the correct direction for my mounting.
Using geometry/trig 101, and wiki http://en.wikipedia.org/wiki/Circular_segment, calculated the correct angle.
Notched them for nesting onto the alum frame and attachment method.
This pict shows 6 "identical" blocks that are cut at @ 7.11 degrees, height of 3.67", 3 used per side.


Missed taking some in process shots.
Basically aligned wood frame over alum frame, with 1/4" overhang all round on inside.
Clamped at 4 corners.
Attach at middle.
Attach at mid support. I used same cedar stock, calc correct angle.
Here shows with 1st end support in place roughly during confirm fitting.
Ended up using 2" decking screws to attach the cedar block to the alum frame and also the wood frame to the cedar block.
All mtg screws on wood frame are sunk just below surface for flush DW laminate mtg.


A composite alum/wood frame curve screen in process.
The small block was cut at 3.55 deg with a height of 0.914"






Nothing like some background AC/DC while working...


Stay tuned, I'll be working on this nightly.
I'm going to get the mounting done next and mount w/o screen.
There will be a border frame attached on top of the wood frame once it is laminated.

Do like Itai did, add just two vertical support bars, his is AT fabric and w/o lights no problem for see thru (I was at his home a few months back). Spaced so your RH/Ctr/LH is not in the way.

Without you will get too much flex, the alum 30x30 is not that strong by itself for that length (I've held them at work that big).

OF course you could do the Mechanical static load analysis, all the parameters are in the Bosch info, if you like doing that stuff.

Few more picts of activity tonight.
Made 4 more blocks to give added stability on the corner along the top and bottom member.
That 4 x 4 cedar sure is good wood to work with, nice grain and does not split.
These were cut on 5.78 deg, 2.42" height, 2 RH and 2 LH's made/installed:



The one on the floor were installed tonight:


Curvature is now consistent w/o any flat spots, success so far!!


Here I took a square and ran it across the top/bottom along the width of the screen frame, constant gap confirms no flat spots.
I could measure the chord height "h" and reverse calculate the screen curvature, for a chord length of 2', to see if it is 39.7' radius, I just might do that tomorrow.



Tomorrow I'm going to work on the wall hanging and see what part of the frame needs to be painted flat black. I'd like to set this at the same height as the drywall viewing was painted, plus give me 2-3 adjustment's up/down in 1" increments, just in case for future proof, so now is the time to make that.

I'm taking Thursday off work, my son has a school field trip, when we get back @ 2pm my goal is install the DW laminate then.
And of course hang it up, re-calibrate the PJ to the DW laminate, and watch the 1st Blu-Ray on it of possible the night.
Finally, light at the end of the tunnel.
I will be working on the black velvet border this weekend, I'm going to the DIY screens forum to see how others did theirs.

Wed 12/3 progress.
-Making & hanging cleats
-1st frame hanging
-rough pincushion check
-determine what on the frame needs painting prior to laminate install (via paintbrush hand apply, not spray paint)

Hanging DIY cleats, I tell you that $39 laser I bought from HomeDepot 7 years ago is one of my favorite tools.
It sticks onto walls via small pin needle extension and you can barely tell afterward.


Frame up and level!
Cleats worked like a charm, and I could easily adjust the frame side-side.
And yes, I do plan on rope back lighting, that is why you see the recessed 120v access, the other gang box houses Cat5e for future screen masking controls if I ever go that route.


Close up of cleat, one each side, nesting into the alum framing.



Side profile, I'm stoked. Can't with for the laminate to be done, which I am attaching via contact cement to the wood (not the center piece).


Pincushion grid study:
My PanamorphUH380/SonyVW60 combo need fine tuning obviously, I put it up there months ago and now will dial it in perfectly after the screen is done.

Ok buddy, you are going to become my screen!
This is a 5' x 12' sheet of HomeDepot special ordered DW laminate.


Measure/score/cut/little "oops" on one side, that's why you give 2" overhang all around for "oops" while cutting and install.


Pre-check, getting ready, kids waiting/watching.


My wife and I did a few dry trials, can I tell you it really is a bear taking a 127" long x 61" wide sheet of laminate and flip it over and expect a good install?
Coordinating hands, having them crossed when the sheet was upside down and then while turning over they became correct, little details that needed trials before actual.
I had to put my Manufacturing hat on to error proof the install process as much as possible.
I came up with these install guide jigs, 3 on the bottom side to center the sheet and line up one edge.
The edge of the center one was the dead center for the laminate, I put a mark on the white side to line up with that.
The other 2 jigs I spaced 1' apart from center, that was about how much of the bottom laminate was there when sagging prior to the center actually touching the wood frame.
We trialed with the jigs 3 times and felt very confident to do this with just us 2 adults.


Glue applied first to laminate, then the wood, in my past experience the wood dries faster because it soaks some of it, so the laminate is best applied glue first, then the wood. I actually turned the fan to the lamiante to get it the same tacky state as the wood, then turned it facing out of the room to remove the fumes, it's winter here in SE Michigan!



It worked!!
Those guide jigs helped so much, easy to line up the center point and have confidence the laminate is where it should be, we gently lowered the laminate (Imagine it is curved, which it is), center touched, then as we lowered it touched from center to sides w/o any gaps. I then took the "J" roller and applied pressure.




I'm going to let it dry tonight and router the excess tomorrow.
That screen is being hung and viewed tomorrow night, time to celebrate getting this far.
I'll be working on the border and post that progress later.

Well, I waited 2 hours after the laminate install and decided to router the laminate before I went to bed tonight. One more thing done, I forgot how messy routering laminate is......now vacuuming.

Early in this thread it seemed that maybe 20mm x 20mm alum frame might be to skinny/thin/not strong enough.

Fortunately for me not so.
I had expected some flexing of the alum frame as I warped the wood and attached it, since it's moment of interia is finite......That why I carefully picked 1/2" thick wood that seemed to me to have enough flex to not curve the alum frame (mostly not flex it) yet when curved gave a "constant curve" for me to achieve the 39.7' radius from AussieBob's calc sheet (for you ifeliciano). The baseboard mldg fit the bill. I spent many times at Home Depot/Lowes trying lots of various products, part of the DIY spirit to learn.

I ended up with about 3/8" "reverse flex" on the alum frame, prior to laminate install. Not bad at all!! If I had used the 30mm x 30mm I'm sure that flex would have been below 1/4" but still there also.
You can sorta see the reverse flex here:


I solved that issue by adding 2 sliding blocks at the center portion whose sole purpose upon screen mtg to wall is to then slide and hold the frame back in plane. These worked like a charm.




So, for future builds what would I recommend?
Honestly, either 20mm x 20mm or 30mm x 30mm Bosch alum frame would work fine, whatever fits your budget and gut feeling or analytical calculations.
20mm x 20mm worked for me and saved some $$'s in the process.
Easy to drill on center, easy to cut, easy to assemble.

I'll weigh this screen project tomorrow, I'm curious where it it weight wise now also.

I just hung my DW 128" screen this morning with my wife's help before I went into work, we watched the morning news downstairs.

I did a quick calibration DVD, then we watched Blu-ray StarWars: The Clone Wars with my 2 young boys, put them to bed, then popped in Blu-ray Casino Royale.
Here's the screen hung, black velvet border is this weekend project, with side profile:




Hey, what's a DIY screen build thread without some screen shots when you are near the end, that's what it's all about: watching/viewing/becoming immersed in the movie and forgetting for a few moments where you are.

So, here are a "few"obligatory first night screen shots:
flash off, just cropped nothing else (my camera skills suck).
All I can say is the detail in the dark/black scenes is so there, the whites are bright and vibrant, the colors come across well like color.

Blu-ray StarWars: The Clone Wars, my 2 and 4 year old boys really-really loved this movie.



Now in 'scope size'


Blu-ray Casino Royale:




The detail and depth in the dark shot scenes blew me away, of course in 'scope size'.

I wanted my border to be very rigid along the skinny length so it would be easy to mount a straight line, but flexible to easily conform to my curved laminate screen.
After trying many-many moldings at HD/Lowes, I settled on this "Tuf Board", it fit all my rqmts perfectly. Easy to cut, can be routered for inside bevel, strong for screwing into (I tested it).
I bought (1) 12' board, ripped in half for the big top/bottom pieces, and (1) 6' board, ripped in half, for the RH/LS sides. They came in at 2 1/2 wide.


Below is my test of the bevel and 45deg miter, ready for cutting the real ones.


Workshop above the 3 car garage, COLD! (not heated yet), but big/open workspace. Lots of white powder/dust instead of sawdust.





I've also embedded (5) 3/8 magnets each RH/LH side for manual masking once these borders are installed.
(2 on top/bottom, 1 on side)
The magnets I use are 3/8 dia Neodymium magnet, you'd be suprised how strong those are, many-many DIY'er use them for blind speaker grille attachments. I bought mine from Parts Express 5 months ago for another project, these were leftovers. I can't find them at PE but amazon.com has them as well, http://www.amazon.com/Rare-Earth-Mag.../dp/B00024DNVC




Here's a simple jig used to help guide straight cuts:

I had (2) 12 foot 1" x 6" boards, loosely put them on (4) scrap 2 x 4's, about 1" gap between both of the 1" x 6" boards.
Made it easy to line up the fabric end and make a reasonable straight cut.
I directly copied this from what I saw at JoAnns in store big cutting table.


Just a suggestion to others:
When you 45miter cut the edge is sharp, take a file/light sandpaper and just hit it slightly to lessen that sharp corner, my first border I did not do that and it poked thru just slightly....live and learn, did for the others and no problem. Black magic marker time for that oops.


Here is the RH border tryout, everything look ok so I'm making 3 more:


3 done so far, clamped to the frame.



Finishing the 4th tonight and then actual attachment to the frame.

My a-lens is not on slides yet, fixed, so I'm watching 16x9 thru the a-lens.
Honestly, sometimes I "compress it" in my SonyVW60 so it comes out correct 16x9 ratio when expanded thru the lens, and at other times I don't compress it and it then stretches to fill the 2.35:1 screen (and people seem a little fatter as well ...Ha)

Yea, I'm giving up some resolution probably for 16x9 when I compress and watch thru the lens, but you know what it looks pretty darn good still.

When I do make a slide for the lens I would expect some reverse pincushion (barrel), because I'm doing the opposite now via curved screen w/o lens, I'll live with that, or just watch 16x9 thru the lens compressed and never slide the lens.

There have been various threads that discussed pros/cons of that in the main 2.35:1 CIH forum.

You know what?
I totally forget to put additional magnets for masking when watching 4:3 material....., the 5 magnets/side I put in are only for 16:9 masks material, therefore when watching 4:3 material most likely I'll just stretch it to 16:9 via the a-lens and watch it.
Don't watch much of that (4:3 material) , though my 6 year old likes iCarley or other kids shows. They are SD and look sorta rough at 4:3, but she does not complain.

Exactly! I tried the PVC in the store and my concern was it was too flexible to hold a good curve, the 1/2" wood baseboard flat 4" mldg seemed "just right" balance between rigid to hold a good constant flex (which I have backed up with 3 supports) vs too noodlely like the PVC is. However, that noodely PVC is exactly what I wanted for the border, for that to not "fight" the alum frame and flatten the curve at all.

The frame, being wood, made it easy for me to use contact cement to attach the laminate.
(contact cement, that stuff stunk up the whole house, even with open windows/fan)

Wrapping the velvet onto the border got done as of 12:30 this morning (I'm red eyed tired), and with my wife's help just attached it to the screen this morning - after 5 hours of sleep.
(Thx to MississippiMan for his tutorial in the "other" DIY screen section).

Border wrap, and underside, not as pretty as MM's but it works for me.



Lots of clamps and used some cut shims to not damage the felt.
Get everything lined up, measure, adjust, measure, adjust, measure, measure.


Put the screen back frame supports on these kids stools, I was able to shoot the drywall screws from behind. My wife patiently held this for about 30 minutes while I shoot the screws, look at the front to make sure nothing moved, corners stayed flat, etc.
I stapled a blue paper towel between the laminate and the center board so no potential for vibration, there is a design slight gap between them but wanted to be sure no vibration/slap issue at high spl's (that is not in this pict)


"Ta da" as my kids say.
Real end dimensions from inside the border with velvet/final attachment:
119.625 width
50.875 height
129.994 diag
2.351 laminate screen calc ratio

So, I'm calling this 130" diag 2.35:1 screen.
Next is the manual masking, that's lower priority, maybe over xmas break, time to finish the rest of the room.

I'll summarize this project final costs, things done right/things done wrong/do different next time while still fresh in my brain in another post.





Ok;
This one of Iron Man is overlay of one taken w/o flash for the nice pict and one with flash for the background (yea, I'll get carpeting soon, etc)

Placeholder for Lessons Learned/Things Done Right/Things Done Wrong/What to do next time post.
[I'll be adding to this over various lunch hour(s)]


-Itemized BOM and budget summary (I'm swagging/memory at work, later will put exact #'s from receipts)

Below totals around $538 using 20mm x 20mm profile.
(not including tools bought, namely electric staple gun, I had the rest)

Alum Framing(Bosch Rexroth framing material )
(5) pieces of 1245mm long (49") 20mm x 20mm, With tax (6% in Mich), $173.42 pick-up at their Madison Heights location, includes their corner braces/hardware
Option: use profile 30mm x 30mm, With tax, $231.43 pick-up at their Madison Heights location. ($60 more)

Screen material:
$138 DW laminate 5' x 12' piece, special order

(1) Can contact cement & (1) brush:
$9 + $2

Wood frame material:
approx $55 for 35' base board molding from HomeDepot, it was 1/2" thick x 4" wide

Frame Corner braces
$10 (4) big braces for outer corner
$8 (4) smaller braces for inner corner
$5 (2) T-braces for center

4 x 4 Cedar post used for supporting the wood frame,
(cut to percise angles for curvature)
$12 for (1) 6' post

Misc Screws/Hardware used
$5 (1) box 1" drywall screws

Border velvet
$65 JoAnns 3.75 yards (leftover enough for 16:9 masking panels)

Border frame material
"Tuf Board" from Home Depot
$10 (1) 12' board, ripped in half for the big top/bottom pieces, and
$6 (1) 6' board, ripped in half, for the RH/LS sides

Magnets for masking
$15 (20) 3/8 dia Neodymium magnet

Masking material
$tbd (estimate $15 max)

-Alternate ways to build this, what I'd do if you wanted these variations:
[add to this later]

a) Use Acoustic Transparent screen instead of laminate
(Dennis E favors AT over laminate for the big screen due to acoustics, I went laminate for short term 2-4 year while kids young, I might modify this screen around 2012 into an AT screen, simple mod)

I've seen tutorials of people stretching AT material over wood frame, I'll post link here (add link)


b) Make flat screen instead of curved screen.
That's easy, when you are at this stage just attach the wood frame.


Why bother with this alum frame method instead of some of the build it on the wall method(s)?
Easy on/off, lightweight, easy to change screen materials for "tweakers".

-Calculations used so anyone could make the support(s) at correct angle at variable distance from center
[add to this later]
http://en.wikipedia.org/wiki/Circular_segment



Solved H for varying C gives the angle need to cut the support at distance from center
(I'll copy/paste my solved equations from excel worksheet, not sure if I can post that excel worksheet itself here)


Just some of my old school equation solving via pencil/paper:

 

Aussie Bob's Omni-CIH CalculatorMikeRHT.xls.zip 67.7666015625k . file

I'll let you know with time, I went laminate based on advice in this thread where I asked How many of you had your screen damaged by kids? (This is my retail or DIY decision)

Laminate is same as any counter top, so should be easy. For now, after I made the screen I just wiped it clean with a damp washcloth just like you'd clean your kitchen counter top.

Since it is basically hollow behind it, as long as nothing gets thrown at it (which I've read about in another post) should do fine.

Good luck and have fun in the process!

It's habit forming, the DIY thing, and your family/friends will be amazed what a DIY screen is capable of.

Dennis E likes AT screen more than my laminate screen from acoustics viewpoint, I assume you are placing speakers behind the AT screen? (I've not checked your build thread yet, that's next for me). Hopefully you've read all the hints on the moire(sp) issue with DIY AT screens and how to avoid that....