Cutting of First Parts

Today I used the CNC router table to cut Last-A-Foam for the first time. That Last-A-Foam makes a lot of dust when sanded or machined. Thank goodness for the dust boot and the vacuum hose, which handled 99.9% of the resulting fine particle waste. The whole cutting job was done in about 15 minutes.

I also micro'ed another set of panels together so that they would be ready to go tomorrow.  I micro'ed them using a different technique than I used yesterday, which was to use a stir stick as a spreader and apply the micro 'bagel and cream cheese' style.

This time I put the micro in a ziplock bag and, after moving the micro to the bottom of the bag with a stir stick (toothpaste-style), I cut out the corner of the bag to make it into a piping bag. It worked quite well as I was able to run a neat bead along the edge of a sheet before mating it to the adjoining sheet.

 

Time Spent Today: 1.0 hr

Official Start of Construction

Construction had begun.
That first step on a journey of a thousand miles has been taken.
Epoxy has been mixed.

The first major milestone in the construction of the Vision EX is the lower fuselage (aka 'the boat'), consisting of the entire assembly of the sides and bottom of the fuselage from the firewall aft. I will be using the alternate 'Fold-A-Plane' method of construction so my first steps are to make about a dozen variously trapezoidal foam panels. While I could lay all of this out with a ruler and a Sharpie, that really isn't my style.  Instead I drew all of the panels out in Autodesk Inventor 2013 and nested them with Cut2D to get the most out of the sheets foam.

The nesting exercise revealed that I need to make three panels by joining stock 24"x48" foam sheets.

Panel 1 is 48"x96" (3 sheets)

 

Panel 2 is 48"x96"

Panel 3 is 30"x48"

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Here are three of the stock panels being bonded together with a paste made from Aeropoxy and micro-ballons. The black things on the panel are mesh bags of lead shot (scuba soft weights). They are there to hold everything down while the epoxy paste cures.

Once everything is cured, I'll take this triple-panel to the CNC router table and let it accurately cut out the shapes for me.

Time Spent Today: 3.0 hrs (including CAD work)

Epoxy Hot Box

Warm epoxy is less viscous so it flows, measures, mixes, and wets out better. Keeping it in a 'hot box' so that it can be dispensed as needed already warm and ready is a great convenience.

Since I still have no supplies (same as yesterday) I decided to build a hot box.  I started by using the sheet metal features of Autodesk Inventor 2013 to work up a suitable design. I saved the unfolded parts as DXF files and then used Cut-2D to create tool paths and save them in g-code. Finally I sent the g-code files to my homebrew 4'x8' CNC router table and had it cut the parts out of some scrap 040 and 032 6061 aluminum I had laying around.









The Vision calls for using Aeropoxy, which comes in cans, and doesn't have pumps for metering, so I will be transferring the Aeropoxy parts into a couple of one gallon jugs with pumps I got off of Amazon. The hot box has a layer of foam insulation lining the inside and each jug is wrapped with about a foot of 4" Flex-Watt heat tape (that happened to have laying around). The resin jug is sitting on the temp sensor of this nice little temperature controller and the heat tapes are attached directly to the controller's A/C output. Very simple hookup.

Here is the finished hot box sitting on the mixing stand next to the gram scale for getting ratios correct and a temp/humidity meter for making sure environmental conditions are within limits for working with the Aeropoxy.

Time Spent Today: 6.0 hrs

The Build Table

I am still waiting for all of my supplies to arrive, which is OK, because as of 2 days ago I didn't have a build table on which to use them to make parts. That has been corrected. For a long time now I have been ruminating on how best to build the table. After all, your aircraft is only as straight as your table. A post by 'Little Scrapper' in the Workshop Tips and Secrets / Tools forum on HomebuiltAirplanes.com suggested that 16 gauge steel wall studs are 'dead nuts straight'. I found a retailer of such steel studs nearby and bought 4 of them with 6" webs for about $15 each. After another stop at Home Depot for a couple of sheets of 3/4" MDF ($30 each) I was ready to start my table.

The steel studs I bought were 12' long so I needed to make the table top 12' long as well. I cut one of the sheets of MDF in half and joined it to the full sheet using #20 biscuits every 6" and a bead of wood glue.

Next I pre-drilled some 1/8" holes in the stud flanges to make setting screws easier. Access to the flanges is a bit tight; you only have about 5" of clearance so I used my right angle drill motor and the super special drill bit you see in the picture (regular 1/8" drill bit snapped in half with a pair of pliers). The right angle drill motor made short work of driving the 3/4" screws through the flange into the MDF as well.




















I attached three of the studs as lengthwise runners left, right, and center, then cut the fourth one into thirds to provide the beams that the runners would sit on and that the legs would attach to. The legs are 2x6 dimensional lumber boards cut 38" long with 1/2" bolts and nuts installed in the ends to provide a way of compensating for an uneven floor.

Time Spent Today: 7.0 hrs

First Order of Supplies

Although I purchased my plans five months ago (November 2015) I haven't done much other than read them and prepare the shop. Preparing the shop did involve a lot of drywall repair, painting, and better lighting, so it was a lot more than just sweeping and setting things in order.

Yesterday things got a lot more real when I placed my first order for building supplies from Aircraft Spruce; foam, Aeropoxy, fillers, peel ply, and lots of miscellaneous consumables (see below). The stuff can't here soon enough. From Amazon I ordered a digital scale, some bottles and pumps to measure out the Aeropoxy with, a pair of stainless scissors and a 'pizza style' rotary cutter.

Qty Ship B/O Item Unit Price Total Price 1 1 0 01-25800 MIXING STICKS BOX OF 500 12.750 12.75 1 1 0 01-14700 3M GLASS BUBBLES 5 LB. 43.750 43.75 1 1 0 01-14900 FLOCKED COTTON FIBER 5 LB. 21.750 21.75 1 1 0 01-25700 12 OZ MIXING CUP (PKG OF 60) 14.750 14.75 2 2 0 01-24902 #3FR EPOXY ROLLER FRAME ONLY 6.750 13.50 2 2 0 01-24903 EPOXY ROLLER COVER ( ONLY ) 4.350 8.70 1 1 0 01-42150 PR2032/PH3660 GALLON KIT 138.950 138.95 50 50 0 01-00642 BID FIBERGLASS 38" RA7725 7.850 392.50 4 4 0 01-13500 LAST-A-FOAM 4.5 LB 1/4X24X96 35.700 142.80 5 4 1 01-13700 LAST-A-FOAM 4.5 LB 1/2X24X96 57.750 288.75 2 2 0 01-13600 LAST-A-FOAM 4.5 LB 3/8X24X96 44.750 89.50 1 1 0 01-12000 URETHANE FOAM 2" X 24" X 96" 73.850 73.85 10 10 0 09-00500 DACRON FABRIC 605 2.97 OZ 3.950 39.50 2 2 0 1080-50 LT.WEIGHT 1.45 OZ INDUS CLOTH 6.600 13.20 10 10 0 01-00641 UNI. FIBERGLASS RA7715/38W F16 10.500 105.00 Subtotal: USD 1399.25