Fuselage III
3/20/2005 7 Hours
Today was the day I had to start the centre console plug. I can't really get the inside of the plane finished now without having the centre console in place. So, here goes.... I've been procrastinating with this for a while, due to the amount of work it's going to be, and the mess and fuss. I bought some 1/8" MDF sheet from Orange Hell a few days ago so I was ready. I guess I better get it started then. Ugh.
I started with my CAD drawings I made and laid out each facet of the part and cut them out of the MDF on the band saw and sanded the edges smooth. I did both sides together (hence the clecoes) to ensure that the whole thing would be symmetrical. Here are all the parts for the sides laid out on the bench.
I spent some time messing around with all this stuff in the actual plane to make sure the fit was right. I think I'm happy now. Time to take all this stuff home and cut the wood to put it all together...
So, I cut a bunch of 2x4 into lengths of 3.75" for the main part of the console, and some pieces 4.75" for the area that interfaces with the fuel pump cover in the plane. The overall width of the console will be 4", and the fuel pump area is 5". Then I enlisted Lucy to come down and hold stuff while I cleco'd the whole thing together. Here's the thing in progress.
Once I'd got all the pieces together for the main body, it was time to glue and screw. So far so good. I can't believe how long this thing has taken me so far already. Once this plug is finished, I have to go and make a mould, then the final form! It's going to take forever! Here's the glued and screwed main section shown with the cleco'd fuel pump section. I have to make pieces for the top, front and back of this thing now, but that needs to be done at the hangar on the bandsaw one night in the week. In the meantime, I should research and order up supplies for making the mould and then the form.
When working on Van's stuff, the cup o' tea must be in the Van's mug!
3/22/2005 2.5 Hours
Tonight on the way home I stopped by the hangar to check the console for fit in the plane. I had to trim a bit off the piece that is going to form the top, but not bad generally. The cardboard mock up and laying it out on CAD made all the difference. Once I'd got those bits done, it was time to go back home and carry on with the rest of it. My biggest issue here is that all my woodworking tools are at home, and all my aircraft tools are at the hangar! Anyways, here's a shot of progress so far. Tonight, I got the tops on and started mounting the front lower piece to the main body. I figured out the mounting angles for the rear filler pieces, but I need to trim them a bit at the hangar before I put them on. My next task will be mounting the front upper piece, which will hold the trim indicators, cabin heat & park brake knobs. Once I have it all together, I'll be doing a lot of filling and sanding to get this looking good. It's not too bad in the raw, but will still need some dress up.
A side view....
3/23/2005 2 Hours
Tonight I stopped by the hangar again to trim up the rear triangular pieces to the exact size. I wasn't there long! Then once I got home, I put them onto the main body of the console. Here's one held in place with temporary screws and clamps.
Next up was the front upper piece. I made a block to suport the sides and cut it to size so that it would seat nicely in the main body of the console. Looks like it's working out well. It's taking a lot of time though. Here's another end of night progress shot. It's time for bed!
3/24/2005-3/27/2005 4 Hours
Over the last few days, I've been tinkering with the centre console at home. This has basically involved some filling and sanding, filling and sanding. Why do I get the feeling I'm going to be doing a lot more of this! I'm glad I ain't building a Lancair! Nothing against Lancairs though, they're gorgeous planes. Here's a shot of the main body after some filling and sanding. Sooner or later, you're all going to get board looking at shots of this centre console that all look the same, so I might ease off on the pics a bit!
I ran some filler down the edges of the top to taper them down to the next surface. This draft angle will help get it out of the mould, and make the centre console look a little beefier.
And the I did more sanding. I've recently done some more filler, but I believe that'll be the last bit on the main body until I paint it and find more trouble spots. I'll also nee to fill the part when I join all the major bits together. Tomorrow, I'll be at the hangar to cut the rest of the pieces so it'll all come together by the end of the week hopefully!
3/28/2005-4/1/2005 6 Hours
I've been making steady progress on the centre console for the last week in the evenings when I get home. I've been doing a bit here and a bit there, whenever I can. This bit takes a while, since I have to fill and sand, wait for it to dry and fill and sand again.
Anyways, tonight, I finished the main filling and I went over the whole part and put fillet radii on it. It's starting to look pretty good. I also put the first coat of primer on it. This will basically show me where all the imperfections are so I can go ahead and fill and sand again! Arrrgh! How much more filling and sanding can there be? Even more I guess when I actually have a fibreglass part. Ugh.
Here are some shots of it in it's current phase...
A side shot...
A rear 3/4 shot...
A close up of how I radiused the edges...
So, tomorrow, this primer should be dry. Then I can go ahead and fill all the imperfections, sand and give it another coat of primer. Once that's done, I'll get some better primer that will protect the plug when I lay up the mould.
4/3/2005 4 Hours
Today was the day I found out that fibreglass is not my bag.... The stuff truly does suck. Anyways, not to be to discouraging, I learned a lot today. One is, grey primer is easily dissolved by paste wax! The other is fibreglass doesn't always do what you want it to do.
So, first off, I went to various stores to pick up some supplies, some modelling clay, some brushes, stirrers, mixing cups and some fibreglass cloth. Then, it was off to the hangar for the moment of truth.
I started out by figuring out how the heck I'm gonna get this thing off the form, since it's practically die locked in all directions. Well, I figured that bit out and made some shut offs for a parting line out of the modelling clay.
Then, I waxed the whole thing up. This was when I discovered valuable lesson number one. Grey primer is crap stuff. It is easily dissolved by the wax paste, and will probably stick quite nicely thank you to the resin. Well, we'll find out sometime this week when I try to pull the shell off this thing.
Next up was to lay up some glass... I started with the armrest portion... I mixed up five pumps of epoxy and started laying up. Hmm seems easy enough. It's going on pretty well. Next up, I decided to do the big flat top area that is recessed down a 1/4", which will hold the throttle quadrant and fuel selector. This was where it all started to go wrong. I couldn't get the cloth to stay down in the corners and come over and down the sides. I ended up laying tape in the trough part, and then putting a small strip along the ridges at the sides. I really have no idea how this is going to work at this point, and resignation was starting to set in. The first batch was barely used, and it was starting to get sticky where it couldn't soak into the cloth too well. Time to throw it away.
I mixed up two pumps this time and went about the sides. Got a layer of glass on all over the whole part. Now about this time, I figured it might be easier not to build a mould, and just use the lay ups I've done as the actual part. If I break it off the plug, and then lay up from the inside, then sand like mad to get the shape I want again, it might work out.
Another thought that went racing through my mind was to have the whole part made using Selective Laser Sintering in 33% glass filled polyamide (nylon). Trouble is, a part this size would probably cost a couple of grand to have done. Ultimately though, the part would come out a finished article, ready to prime and paint, and it would include all the ribs, cutouts, bosses etc that I would need to make this thing work. Maybe I should make a better CATIA model and send an STL file out for quote. Anybody know any rapid prototyping shops with SLS capability that could do me a deal?!
So, here it is as I left it. 4 hours it took me to get this far, and I'm not confident in how it's going to turn out. I'll stop by the hangar on Monday or Tuesday to see how it worked out. Keepin' me fingers crossed! By the way, the whitish areas aren't air bubbles, it's where the grey primer wiped off the part revealing the white undercoat. Grey primer, not exactly suited to this application!
Last night after footy (soccer), I went to the hangar to inspect the console... It seemed OK, so I pressed on and laid up the front half. Then, went home to bed. I think I'm getting better at this game, coz it didn't take me nearly as long to do this bit.
Well, tonight on the way home from work, I stopped by the hangar to pull it all apart. Basically, I had it in my mind that I could take it off the form, lay up inside, and sand like hell to get the shape. Well, it wasn't too hard to get off, which I must admit came as a bit of a surprise. Once it was off though, it was way too flimsy to really do anything with. Here, is a shot of it lying on the bench. I cleaned up the form a bit too!
Here it is displaying all it's floppiness...
So, next steps... I inspected the inside surfaces of the fibreglass and it actually came out pretty well. Well enough in fact to inspire me to go down the make a mould road instead of trying to short cut the job. I guess you have to try these things to learn right? Well, this is an experience for me, for sure. So, now I've cleaned the form, I'll take it home, smooth it out a bit more in the corners where resin stuck a bit and then go for it big style. There's gonna be a delivery of glassing supplies tomorrow from Spruce, we'll be all set. Can you tell I have a new found confidence?!
Here's a shot of the front portion. I'm planning on using this piece, since it will easily slip over the form, and I can the go ahead and stiffen it up a bit. Then I have something to go with right away instead of having to make more shut offs in clay, blah, blah...
I will also put down some resin into the corners with cotton flox in there to help get the corners right. Surprisingly, the corners weren't really too bad, and I could live with them as they turned out. A bit of flox though will probably go a long way toward getting this thing right. Stay tuned!