Instructables

Carbon Fiber Tablet Mount - The Kindle Kradle

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Intro: I recently joined the ranks of the Gadgetistas by buying a tablet (Kindle Fire HD if you must know).  While that may not sound like a big deal to many, for a guy who hates cell phones and doesn't own one, it's about as difficult as a bureaucrat being honest: it happens, but not that often.

While reading and watching movies on the tablet is super-nifty, holding it for two hours while reading or watching a movie is most definitely not.... and since I tend to do those things while lying in bed, I figured I needed to make a really cool bed mount.  (This is really nothing new for me - about 10 years ago, I built a "bed mount" for a portable DVD player that works like a charm - but this one had to be a step up - See Step 14).

Since I tend to use smaller projects as introductions to new materials, I figured this would be a great opportunity to introduce myself to carbon fiber and epoxy on a smaller scale in preparation for some much larger upcoming projects. 

Cost: is up there - I almost don't want to know - but I'd guess it's in the $300-$400 range with some of that being acquired tooling.  If building a bed mount was my only goal here, I would have chosen a different method, but since I tend to look at projects like this as a vehicle for learning a particular skill set and acquiring specific tools and materials,  I'm OK with the extra expense (how much would a college course cost you?).  A mount of the same design could be built for less than half by choosing different materials (fiberglass) and tweaking the techniques - for example, choosing a wet-layup over foam technique over vacuum bagging in negative molds (but would require more cleanup).

General Materials List:

RAM mount - Model RAP-B-138U (sometimes, it makes more sense to buy something if it will work)
Kipp (brand) Lever Clamps
Hard Maple - or some suitable hardwood not prone to splitting under focused pressure
Carbon Fiber Fabric (8K Twill in this case)
Fiberglass Cloth
Fiberglass Matt
Breather Cloth
Peel Ply
Vacuum Bagging Material (plastic)
Mastic Tape (For sealing vacuum bags)
Polyester Resin and MEKP
Polyester Tooling Gel Coat and MEKP
Epoxy Resin and Hardener
Epoxy Glue - 5 and 30 minute versions
Spray Adhesive (3M Super 77)
Fumed or Colloidal Silica (Smooth-On's Cabosil) (thickener for epoxy)
PVA (Polyvinyl Alcohol - not to be confused with Polyvinyl Acetate) - Mold Release
High-Quality Carauba Wax
Urethane primer - or a good sandable primer
Catalyzed Urethane Clearcoat
Urethane Reducer
Lacquer Thinner
Acetone
Sulfur-Free Modeling Clay
Petroleum Jelly
Tempered Masonite (hardboard)
Melamine and assorted sheet stock
Smooth-On Plasti-Paste II (not required - just convenient)
Plastic wedges (SUPER helpful - worth every penny)
Chip (disposable) brushes, disposable graduated mixing tubs
Plastic squeegees (a couple will do - if you keep them cleaned off)
Mixing paddles/sticks
Gloves.... lots and lots of gloves.... A tyvek suit would be a good investment, too.
A **quality** Organic Vapor Mask and goggles
Vacuum Pump (some way of generating a vacuum)
Various fittings and tubing to run vacuum lines to your vacuum bag setup
Vacuum gauge - so you can see what's happening (probably not 100% required).
Sandpaper - Wet/Dry 320 and 400 - carbon fiber laminates eat this stuff quickly
Plus a bunch of smaller items like drywall screws, tape, hot glue, wood glue, carpet tape,
Miscellaneous tools: Drill press, table saw, bandsaw, router, dremel, files, wrenches, hand drills, saws, etc.

Safety:  As you can see from the above list, you'll be working with some pretty nasty stuff.  Since it would take me 30 pages to reiterate what already exists, I'll hit the high points of what goes through my mind when working with nasty/unknown materials:
  • READ the MSDS (Materials Data Safety Sheets) that come with chemicals and know what they can do to you.  This way, when you sprout that third arm because you were too manly to wear a vapor mask, you'll know why.
  • Don't overestimate your capabilities - always bet on the conservative side of what you can handle until you're in familiar territory.  It's far more embarrassing to lie on your garage floor crying for help than it is to approach things thoughtfully and progressively.
  • Think through your process - what safety gear and props (paper towels, solvent, etc) will you need?  What could go wrong?  What will you do if something does go wrong?  When you have a good idea, make sure all the things you need are readily at hand.  Having a helper would be a really good strategy as well - but you should plan as if they're not there.
  • When working with resins and epoxy, be *very* aware of what temperatures can do to your pot life and cure times.  Most pot life estimates are given at around 72 degrees F - and you can figure that for every 18 degree increase in ambient temperature your pot life will be cut in HALF.  Nothing sucks quite like being half-way through a layup or surface coat and have things start to gel - that's a mess with a capital "M".
  • Carbon fiber - once trimmed can be ninja sharpWatch out for those edges - and knock them down ASAP.   I ended up with a littany of little cuts because I'd read about how sharp CF could be, but didn't realize that they meant SHARP-sharp as opposed to worrisome-mother-sharp.
  • I can't stress enough the value of protecting your lungs, skin, and eyes at every opportunity - a $45 vapor mask is far cheaper than glass fibers in your lungs or being sick for a few days from polyester vapor exposure.  You have to live in your body for the rest of your life - don't screw it up if you can help it.
  • NEVER clean resin off of your skin with solvents.  Solvents will carry the resin molecules through your skin - directly into your bloodstream (especially acetone and reducer).  If you get resin on your skin, use waterless hand cleaner like Gojo Orange or similar.
Alright - enough Hall Monitor babbling.

I've included a few drawings - don't take them as set in stone - but they give something of an idea what I was thinking of ;)

I'd also recommend John Wanberg's Composite Materials Fabrication Handbooks

Note that there are SO many photos in this Instructable that I won't be doing a lot of writing - I'm going to let this be a "picture story" (my favorite kind!) :)

FINALLY: If you like this Instructable, please take a moment to vote for it in the UP! 3D Printer competition :)  Thanks!
 
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Really nice work keep it up!!!

andrea biffi2 months ago

really awesome! congrats!

wilwrk4tls1 year ago
Maybe you mention it later, but I'm thinking props need to go out to the Zyliss- the Zyliss rocks!
jwilliamsen (author)  wilwrk4tls1 year ago
Absolutely - I give it a lot more credit in my custom gun stock instructable - but it's one of those tools that once you have one, you kind of wonder what you did without it :)
wow, this is professional work indeed
crispycat1 year ago
Wow .. you have made a text book carbon fiber layup in such detail that it should serve as a pre requisite to anyone that wants to use carbon or fiberglass for the first time!
its taken me 2 years and alot of failed attempts to get items as good as yours!
the only things i can think to add is to give the carbon pieces a light going over with a cutting compound like Farecla Profile 500 which will bring it up to a nice shine then spray it with a 2k clear lacquer (mainly used on cars) to give it the glossy look most professional carbon items have
jwilliamsen (author)  crispycat1 year ago
Thanks for the tips on finishing! I haven't looked into the cutting compound - but I probably will for my next CF project (an excuse to get a good buffer!). I'm also going to be looking at "GC50" which is an epoxy-compatible gel coat to achieve a very deep-looking finish.

I didn't shoot a gloss clear on this project mostly because the furniture in my bedroom is semi-gloss and I wanted it to match - but my next project (CF wall cabinets) will probably get a mixed gloss/semi-gloss treatment.
i havent used that one before sounds interesting for the polishing/sanding capability... i have had the clear epoxy gel coat from easycomposites.co.uk and its a nightmare to spray you need at least a 4.5mm nozzle which is not easy to get at a reasonable price which is why id suggest car clear coat which is a lot thinner.. the ones listed as 2k ive found best and most forums will advise...
however the gc50 looks good just find out how difficult it is to spray before you get it as while it can be painted its never easy to get an equal layer with a brush and sanding is never fun hehe
jwilliamsen (author)  crispycat1 year ago
Thanks for the information on the GC50 - it's good to hear someone else's experiences with it. I would imagine the only way to apply it would be with a cup gun - and they're not cheap.... hmmm... maybe I should stick with spraying urethane.... The project I have in mind is mostly subtly curved flat panels - so getting a good even coat would be about as easy as it would ever get.... Part of the reason I was interested in the GC50 was because I want to use a heavy carbon spread tow as a "beauty layer" and didn't want to have to deal with print-through on the clear coat (which may or may not be a problem coming out of a female mold....

Just to be clear, when I said a mixture of gloss and semi-gloss, I'm talking about a piece of furniture where the CF would have a gloss finish, and the wood and supporting parts be semi-gloss.
Yeah I don't plan on making the lamp but the carbon fiber instructions are very useful.
madvic1 year ago
Stop doing this...!!! You are wasting your talent...!!!
With your craftmanship level proper of a master artisan you could build Airplanes!!
Very instructive and awesome!
RedBinary1 year ago
That is very VERY nice! I've made a couple of tablet/phone mounts for my vehicles out of sheet metal that have a similar cradle portion. Maybe that is what will be the project that makes me cross the carbon-fiber line that I've been putting off for so long! It just seems so cost & space & labor-intensive!
jwilliamsen (author)  RedBinary1 year ago
Thank you! :)

Yeah.... CF isn't a cheap date, that's for sure. A decent quart of epoxy resin and hardener (West Systems) is going to set you back $50-60+ and a yard of fabric will run around $40. Admittedly, I built tooling that would work for small-scale production and not really typical prototype tooling (because I wanted the experience). As far as the room required, it's not excessive, really - but you do need a space where having polyester resin fumes hanging around isn't going to be a problem for a few days. If you have access to sheet metal working tools, you can make forms for your shapes that will yield a nice surface finish - I would have gone this route for the "cradle" portion had I had access to the right forming tools.

I'm planning on trying two other techniques for CF - a positive silicone insert for the mold and possibly a fiberglass male/female mold. Both of these techniques use more mundane clamping pressure during curing, and don't require a vacuum pump, mastic, bagging material, peel ply, breather, hoses, valves, etc, etc. so the layup process should be a little easier. I'd also like to try using Hydrocal as the mold material - just to see what it would take to get it to work (it'd be much less expensive than fiberglass) I'll be sure to post Instructables on those techniques when I get to them.
Sleep E1 year ago
You have the character of an old world craftsman and the technical acumen of a modern day master. Beautiful work!!!
jwilliamsen (author)  Sleep E1 year ago
Thank you, sir :)
Gastonone1 year ago
Hello,

Please inform your selves.
Carbon fibers may be more cancerous than asbestos.
jwilliamsen (author)  Gastonone1 year ago
While I can't find any information that backs up the claim of CF being a carcinogen (what *isn't* in sufficient quantity?) this just reinforces what I've always believed: Read the MSDS's. Protect yourself from dust of any kind. Keep solvents and chemicals off your skin. Most chemical damage is cumulative - so it can seem like they're not affecting you until a ways down the road when suddenly you might suffer some pretty serious reactions to exposure.

While CF itself isn't that dangerous (no more than fiberglass), sanding epoxy resin that isn't fully cured and breathing the dust is - so always wear a good quality mask or use a fresh air system.  I don't think anyone ever ended up with cancer from breathing too much clean air
bigbigdave1 year ago
Holy cow! First off, I have no current plans to do any carbon fiber work myself, but I'm so glad I took the time to read your Instructable. It is so excellently done, the photos are fantastic and the level of detail compelled me to read every bit of it. Thank you so much for taking the time - just stopping and shooting all the photos had to add hours to your project, plus the time and effort you clearly put in to your annotations and uploading the entire thing.

The actual project itself seems rather daunting to me given the "positive-negative-positive" steps required, combined with all the layers of chemicals and whatnot, but sadly, my wife just looked over my shoulder and saw the final page of beauty shots. The sound she made means I'll likely be attempting this (or something similar) at some point in the future. At least I know where to come for a fantastic set of instructions.
jwilliamsen (author)  bigbigdave1 year ago
LOL - sorry Dave ;)
nunyafb1 year ago
Not having done extensive research, I will still go on the record. This is the finest Instructable I have ever seen produced and should be used as "THE" example of how to produce an Instructable. The project employes several disciplines, merging them into a functional piece of art. I seldom leave comments but I just had to express my complements to your work. Regards Jim
jwilliamsen (author)  nunyafb1 year ago
Wow - thanks for the kind words :)
jahred29331 year ago
I envy this wonderful holder!! Wish I had your skill or wish I could buy one. In any case, you did a spectacular job. Not for the beginner.
jwilliamsen (author)  jahred29331 year ago
Thank you - and you're right - it's not really a "beginner" project - but everyone starts out as a "beginner" at some point. A big part of making is having the willingness to try something new, going through the process, and learning from your mistakes. I always tell people that even the most complex projects are a series of "baby steps" and that's how I generally approach them.
you sir... are a genious
jwilliamsen (author)  licenseless1 year ago
lol - Well, maybe not a genius - I'd settle for "obsessive" ;)
Wow. This is thorough. Thank you so much for sharing this project! It's loaded with great information.
jwilliamsen (author)  audreyobscura1 year ago
Thank you. It was a HECK of a project and I learned a lot - just hoping to pass some of it on :)
ikssk1 year ago
Nice, love your work.
jwilliamsen (author)  ikssk1 year ago
Thanks :) I liked your "copycat" version of my fireplace. I found it by accident a while back and was like..."Hhheeeeyyy, what does that look so familiar?" - lol Nice work, BTW :)
Excellent work. I'd love to make something like this from wood for my ipad. I want it to be able to completely hide behind the headboard when not needed though.
jwilliamsen (author)  Marcaine Art1 year ago
Thanks :) I think what you're imagining *could* be done. It would be a heck of a design challenge for sure. I have a friend who makes motorized flat-screen TV mounts that retract under a bed - but that's a simpler problem since there is only one "target" position once it's fully deployed.

Well, if you ever design that, I'd love to see it :)