Floorboards for templating, Free

Bartman

Bartman

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I think they are for heel brakes but just use the outline and cut whatever holes you need.

Pay shipping and they're yours or pick up in NJ.

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Neat! Looking at that pile of plywood, I can see how swapping out the plywood for CF plate can really save a ton of weight.

Any chance to turn those into a CAD model so that the information is permanently captured? I'd be happy to make the 3D model if someone there could get me dimensions.
 
Anyone have a material source for the CF board? I'm about to replace mine, looking at birch ply.
 
Big Ed said:
Anyone have a material source for the CF board? I'm about to replace mine, looking at birch ply.
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You could look at Dragon Plate, just be aware that they're $$$.

You could also make your own plate. It's pretty easy if you can relax a little on the specs. It'll be a teensy bit heavier than from Dragon Plate, but much, much cheaper. If you take two sheets of glass and use vacuum bagging techniques, you can make a pretty decent "press".
 
kubark42 said:
You could look at Dragon Plate, just be aware that they're $$$.

You could also make your own plate. It's pretty easy if you can relax a little on the specs. It'll be a teensy bit heavier than from Dragon Plate, but much, much cheaper. If you take two sheets of glass and use vacuum bagging techniques, you can make a pretty decent "press".
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Priced that stuff, it's bananas. The factory boards aren't that expensive. Less than $1K for a full set.
 
How much weight is saved with the composite floor boards over the plywood? I work for an aerospace company and I am thinking of making some floorboards for my 7KCAB.
 
I think that would depend on the relative density of the material you used. I guestimated that it would take roughly one 4x8 sheet of material to do the trick, so ~32SF. Google sez 1/4" Baltic birch ply has a weight of 0.9 lb/sf, so that's about 28 pounds. A composite with a density of 0.5 lb/sf would save you somewhere on the order of 10-12 pounds.
 
Michael Panek said:
How much weight is saved with the composite floor boards over the plywood? I work for an aerospace company and I am thinking of making some floorboards for my 7KCAB.
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This is guesswork until someone provides something more definitive, but looking at https://www.epoxyworks.com/index.php/comparing-cost-and-weight-of-flat-panels/ and figuring that that's 3/8" plywood and there's ~15 sq ft:
  • ~1lb/sq ft for plywood, so an initial weight of 15lbs
  • ~1/3 lb/sq ft for sandwich composite, so a final weight of 5 lbs
That looks like a savings on the order of 10 lbs[*]. Certainly not just 5lbs, and definitely not as much as 20.lbs Not the cheapest way to save weight (that's probably a SLA --> LiFePo4 battery conversion), but a good CG neutral way to do it.

But definitely the most fun way to do your own weight savings! I'd love to be part of a floorboard project if you'd be interested.

[*] This doesn't take into account removing carpet. I hear that's several pounds more, at the cost of some extra noise.
 
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I am thinking of 6-8 plus of Toray 700 12k prepreg carbon. I am uncertain of the need for core "divinely, or Rhoacell)
 
If you find a cost effective material and source, please share here. I'm planning to make new floorboards from baltic birch plywood this winter. Would love to try composite instead.
 
Michael Panek said:
I am thinking of 6-8 plus of Toray 700 12k prepreg carbon. I am uncertain of the need for core "divinely, or Rhoacell)
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I'd hardly consider myself an expert on composites-- sounds like that's you!--, but the work I've done makes that sound perfectly sane. I'm assuming you have the ability to easily mill the plates to final size so thickness won't impact post-curing processing.

I feel the important failure mode is penetration at the brittle upper surface. Aside from that, strength is probably not that important. I don't believe those panels are structural, so as long as they don't break through-- which would be very sad for the fuselage fabric underneath--, they can probably be the bare minimum thickness to withstand puncture loads. Maybe an upper innova/basalt weave for impact resistance, or perhaps just carpet.

If fall-through damage were a major concern, the floor could have a dyneema trampoline underlayment. We use dyneema trampolines on boats, and they're as strong and light as anything you could want.
 
I was just going to use scrap pieces with a full coverage ply (top & bottom). I am sure that it would be just as strong as 1/4" birch plywood. I was going to clear coat it (no carpet) for a nice finish with aluminum scuff pads for the rudder pedal areas (who stands on their airplane's floor anyway?). Also looking into a carbon instrument panel, switch console, throttle and trim quadrants.
 
I stand on mine, or kneel, when I yank the seats to work inside. But it is braced pretty well by frame members, so the widest span is probably 12 inches or so.

I have seen a couple of interior parts done in hydro-dip transfer that looked great. I like carbon fiber, but someone gave me pause when they called it "the fake wood veneer of the 90's", which is basically true.

The factory composite floors look fantastic. But unless I can find a reasonably priced material source, I'm going with birch ply and clear finish too. Wondering whether using quality aircraft-grade plywood might allow 3/16" instead of 1/4"?
 
What I fabricate for my airplane will be 100% carbon fiber, through and through. One I get the toolong/pattern done I might be able to go into production!



NOT!
 
Big Ed said:
The factory composite floors look fantastic.
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I wonder for how long it keeps its looks. Laminating resin is soft and scratches easily. Dirt tracked in will quickly abrade the finish, and it will lose its luster. Perhaps going with a matte finish or even a clear anti-skid coating will allow the original aesthetics to survive the decades.

Michael Panek said:
What I fabricate for my airplane will be 100% carbon fiber, through and through.
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A thought which just occurred to me is that using a foam underlayment, even if it's just the green insulation stuff from Lowes, will probably go a long way to reducing vibration and noise. It would add negligible weight and complexity.
 
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I cheaped out. Took the originals, sanded and filled minor imperfections, stained them black, coated them with epoxy varnish, re-installed them, and quite happy.
 
I went for the weight savings. Throw out the carpet (keep the data plate). ACA carbon floorboards. No increase in noise and no vibration that I have noticed. Also you do not need heel plates. The material does not wear.
 
I plan on using Toray 700 12K (prepregnated material that requires to be cured in an oven under vacuum). The same stuff the big boys use!
 
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