Scratch Build – In Progress Project: OSIDIAS - Carbon fiber and 3D printed SFF (Jan. 2, 2020)

That's what the mdf center is for.

 

You know, the CF is really distracting for me. I find that every time I unroll it, I just can't help but stare at it. There's a quality about it that you can't capture in a picture.

I'm not that concerned about it. Even though I'm using 1mm aluminum, there's only about 4cm between the MDF pieces on the core. It should take quite a bit more vacuum than I'll be able to give it to make it bow.

Thanks Attila. Those are some pretty high compliments coming from an aluminum master such as yourself.

Go for it man!

Thanks. I don't think it will be brittle. I took a look at the small test piece I made last night, and it turned out 95% okay. There's still a very, very slight tack to it. I'd say I might need a little more hardener in the mix, but I don't see anything that would indicate brittleness of any kind.

Exactamundo!

 

Are you planning to fasten the aluminum skin to the MDF before using it as a mold for the carbon fiber? I was wondering whether there was a need to fasten the seams on the top and bottom together. Or will the vacuum bag pull the two pieces together without causing an overlap or an opening that would permit resin to squeeze through?

 

The MDF won't be fastened to the skin in any way. The fit is perfect (luckily). I will use a small strip of tape on both the top and bottom seams to prevent resin from leaking through. The tape will be thin enough not to cause any ridge in the finished product.

 

It looks amazing anyway
I didn't understand how you keep in place the CF once you turn the mold to cover the other side

 

Nice start mate! Looking forward to see more from this project

 

Thanks! The resin will act almost like an adhesive when applied to the CF and the mold. It won't fall off when I rotate.

Thanks as always mate!

 

I have done some vacuum bagging and you will, almost certainly, get some bowing in between your MDF forms. Just get some cheap white foam and fill the space in and you will avoid buckling of the aluminum.

Just for a test, put your vacuum bag around your existing setup and pull it down. check if there is any buckling, I could be wrong.

 

so how will you get it off of the mold?
are you going to grease it or something?

 

I do know that it takes quite a bit of force to have any deflection by hand. I'll bag it beforehand just to doublecheck though. Good idea.

I'll be using a mold release wax. The other option is to wrap the mold with some of the peel ply that I have. Either method would work, but the wax would be the easiest.

 

OMG

CARBON FIBRE?!

How much are u going to fork out on this case?!

and im subbing this for sure (first sub yay )

 

Yeah, good old CF.

Well, the cost is something that has been asked about quite a bit. Granted, carbon fiber isn't cheap, but to build the case out of aluminum would have been pricey too. I would rather spend and extra $100 or two, to make something infinitely more exotic. However, it's not just that the material can be costly, it also raises the stakes for errors. If I were to screw up the case shell alone, well, that's $150 I'll never get back... I've never been one to take the easy route, and a few extra dollars in the grand scheme of things seemed pretty justifiable. I guess the end result will tell the story.

Also, for those of you ever so patiently waiting for an update... I'm composing one right now. It'll hit Losias first, and then here. I won't update any place else until tomorrow night, since I'm actually out of town right now. I just wanted to give my bit-tech friends a little love!

 

Ready guys?

Well, working with the carbon fiber was an interesting experience. I got completely prepped and ready to go last night, so that I could start wrapping first thing this morning. I'll admit to being a bit nervous. I didn't have any room for error, and with my OCD about having things perfect, the pressure was on.

I woke up this morning, headed to the shop, and cranked up the music. A little Zune Pass with Breaking Benjamin as the starting point, and things were underway! What you'll see here is the mold ready to go, with the carbon fiber strips sitting on a tube right behind it. This would allow me unroll the CF onto the mold with minimal handling.



It was now time to mix up the resin. I was using a marine grade clear epoxy with a 109 medium hardener. This stuff has a pot life of about 30 minutes, so there was no time to do anything but get underway. With the resin mixed I was on the clock. I slipped on my rubber gloves and hit the mold with a layer of resin from a 4" lint-free roller. The first layer of CF was on soon after.

I continued wrapping and rolling, taking extra care not to deform or stretch the CF in any way. I also had to be sure that all the corners had the fiber nestled in them without issues. I thought I was making good time until I went to apply a little more resin, and the roller started to pull up on the CF. Crap! That meant my resin was hardening. Had it really been 30 minutes already? Well, it didn't matter. I couldn't do anymore at this point. I needed to wrap peel ply around it and get it bagged. I still had one layer to go, but there was no way I could get it on without causing serious issues. So, bag it, I did...



I smoothed the bag out a little and left it under vacuum for about 2 hours.



Now, aren't you all excited to see what's next? Yeah, I am too, but I had to head out of town for the rest of the weekend. The next update will likely be on Monday.

So, overall, the experience wasn't as bad as I thought it might be, but I was cutting it close with the resin cure time. I also know I'll have a few ridges in the resin from the bagging process, but that's really not an issue right now. I can sand and add more resin. In addition, I'll likely go ahead and add the last layer of missing fiber. I'll update early next week guys!

 

Looks like you did a great job with that Carbon Fiber.
Can't wait to see the CF off the mold.

 

oooh this is gonna be awesome!

i think you could probably prolong your working time by adding less hardener?

 

*foaming at the mouth

 

That's amazing! How many layers of CF? Did you get any kind of seam where the layers overlap?

 

Way to go, taking it to the next level!

 

Looking forward to more!