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td_howard

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Everything posted by td_howard

  1. Hey Brent - I'm a Cozy IV builder in Edmonton, but I have recently begun an active search for a Long-EZ to fly while I complete my project. For sure I would contact David Orr at www.canardfinder.com. He runs a brokerage service for canards, and is an experienced EZ driver with a wealth of knowledge and advice. At any given moment he probably knows of 30-40 planes that are on the market and has personal knowledge of many of them. Most of these will never be seen on barnstormers, ebay or the like. I would also join EAA and/or RAA. They have many articles and fora that could give you advice. EAA Chapter 1410 in High River just had a seminar on this very topic - check out their website at www.eaahighriver.org. www.ez.org has some good articles on buying (or not buying) canard planes - nothing Canda-specific, though. Key thing is to get as much information as possible. You might try contacting other canard drivers in your area. According to the Transport Canada database, there are at least two EZ's in the Calgary vicinity. Best of luck with your search - PM me if you want me to keep you updated with the status of mine. Trevor Cozy MK IV, #1171, Ch. 19
  2. Dust, thanks for the input. Alas, I have already cut out the depression (depressing?) areas and micro'd in new foam. Actually, the first ply was not too bad - most of the bubbles were between the two plys. Dunno how that happened. Ah well, no big - won't take that long to fix.
  3. Hi all. I had some problems with my fuse side layups which I didn't find addressed in the archives. Thought I would post my experiences here (and what Nat said about them) to hopefully assist future builders. This has also been x-posted to the cozy list. 1. Longeron gaps Plans say there should be no gaps when you lay the longerons down on the fuse sides. Trouble is, the longeron strips are supposedly .25 thick, x 3 = .75" thick, while the longeron doublers and the long stiffener strip which attach to them on that dimension are both .7", which leaves a .05" discrepancy. In my case the longeron strips must have been slightly thicker than .25", because my glued up longerons are slightly more than .8" thick. I attached the doublers and stiffener so they would be flush with the main longeron structure at the "top" (ie, the side that faces in when the fuselage is assembled), to avoid a joggle there when you glass over the longeron with the 4-ply UND. The result for me was a .1" gap along the longeron bottom (where it joins to the fuselage) in the region of the front doubler and the long stiffener strips. The main longeron structure fits tight against the side, but not the stiffeners or front doublers. I handled this by applying sufficient flox on the underside of the stiffeners and doublers so that plenty was squeezed out when I clamped the longerons down, and by troweling in extra flox to eliminate any gaps. Nat said that was the correct thing to do. 2. Fixing air bubbles in the depressions. I did a crappy job of getting the UND to lay down in my control stick and fuel gauge depressions, so I'm going to cut them out and re-do them as per the repair procedure in Ch. 3. (May as well learn that one early, eh?). That procedure specifies that you need 1" overlap per ply of glass, but since the depressions are so close to the top (and the longerons) you don't have enough room for that much overlap. Nat said it would be OK to use only .5" overlap here, and that it would be OK to overlap onto the longerons if necessary. Rather than just remove the glass and glass over the foam, he suggested cutting out everything, laying down a release agent (such as plastic or wax paper) on the (now exposed) masonite so you do not glue your patch foam on to the jig, and putting in a new piece of foam, then glassing. This is approach I am going to take. I did experiment with just trying to get the glass off the foam using a combination of heat and prying, but because of the marginal thickness of the foam in these areas, it's difficult to get the glass off without tearing the foam anyways. I also had air bubbles along the top spacers, which I just injected with epoxy. Ch. 5 "big layup" post-game review: a) get helpers. I did mine alone, which probably doubled my elapsed time. b) Work out from the center rather than everywhere at once. (Hmmm, doesn't Ch. 3 tell you to do this?). Get the depressions correct and move outwards from them. Which brings me to.... c) Re-read Ch. 3 before you start. You've been building jigs and doing a lot of woodworking-type stuff after chapter 4, so it's probably time for a refresher. d) ensure a good micro fillet exists along the spacer edges. I thought I had done this, but obviously, not well. e) work methodically over small areas. Get each one right before moving on. Don't think "I'll get back to this and fix it later", because you probably won't have the time, the epoxy will have set up, or you will be too tired. f) do each side separately. I was getting very tired at the end, and you tend to rationalize away problems (like air bubbles) when you get punchy. Other things from prior to the layup I just remembered: g) when using the sandwich bag method of applying 5-min epoxy fillets, mix it up first and then put it into the bag. I tried just putting both components in the bag and squishing it around, but in at least one case something was off because it only hardened into a gummy mess, which required me to cut out the joint and re-do it. h) the edge thickness of the 3/8" PVC foam seems to vary by as much as +/- 1/16" from sheet to sheet, so when you 5-min them together, you may get a joggle. Sand them flush prior to gluing them! (This is actually mentioned in Ch. 20!) That's it. This layup took me a long time, so I was a bit disappointed with the results, but the nice thing about composite construction is that everything (well, OK,most things) is/are fixable. In the immortal words of John Slade "no one will ever know..."
  4. I concur. I have used it for worktable, jigs, and basically anywhere the infamous "straight pine board" is required. Ha! Anyone seen a straight pine board recently? All the ones I see at Cheapo Depot you could use straight away as propellers. MDF is heavy as hell, though - makes me wonder what "High Density Fibreboard" would be like. (if there is such a thing)
  5. Prices must have come down recently - when I did this a couple of months ago, you couldn't get a digital scale for < CDN $60! Anyway, just thought I'd mention that so far my pump is working flawlessly on MGS 285. I verify it on the first pump of the session, and it always checks out OK. One thing slightly worrisome is that if it has been sitting for a while, the first pump contains a small discharge of what I assume is the seal lubricant from the hardener tube. When mixed up, the expoxy is clear, and subsequent pumps are clear. The epoxy hardens OK and gives a positive scratch test. I also did a peel test using one of these "cloudy" batches and could find no difference between it and a "clear" batch, so I haven't been too concerned about it. I found a reference to this in the archives, but the poster just mentioned it in passing and basically said what I just did- that he wasn't too concerned about it. 3 pumps MGS 285 is about 63 grams (45g resin, 18 hardener), so 1 pump is 21g (15 resin, 6 hardener). Your worst case scenario is underweight of resin and overweight of hardener so at 2g resolution, that would be 13g resin, 8 hardener, for an obtained mix ratio of about .6, a 50% deviation from the required mix ratio of .4 for MGS 285. At 1g resolution, the worst case scenario (14g resin, 7g hardener) gives a mix ratio of .5, which is still 25% off. This is still not in my comfort range so when I use the scale, my min. batch size is about 50g. Of course, things get better the more you mix up. At 63g total weight indicated, a 1g error yields a worse case ratio of .43, which is probably OK for our purposes. Having said all this, I only use the scale for special purpose (ie all slow or all fast hardener) batches anyways. Note if you have a scale that goes to up to 3kg or so, you will be able to weigh all your early parts, so you can compare them to the weights posted on Marc's site and elsewhere.
  6. I use both pump and scale. I have a 60/40 mix fast/slow hardener (MGS system) in my pump, and I use that for 90% of my layups so far. But I also have condiment squeeze bottles of resin and hardener (both types) in my hot box, so if I want a layup to cure faster or slower, I use the scale to mix up a batch of expoxy with the appropriate hardener. I have a chart attached to the front door of my hot box showing the required weights for various sized batches of epoxy. I also use the scale to verify the accuracy of the pump at the start of a work session. BTW, you can get fairly cheap digital scales from here: http://www.stores.ebay.com/digitalscalesdirect A 3KG scale goes for about $30 if you buy it direct, you may be able to get it cheaper via auction.
  7. Rui, you might want to reconsider this. My table is 4' wide and at 5'8", it's a real stretch for me to reach the other side. And trust me, there's ALWAYS something you need on the other side! I would go a shade narrower - Dust's 42" sounds about right. I don't think there is any assembly on the plane that needs more than that. BTW, I also used the engineered floor joist system (two 12' along the sides, with a third one cut into 3 4' sections and used as cross-braces, glued and lag-bolted together. 3/4 MDF on top, 1/4" ply on the bottom). I check it occasionally, and even with temperatures and humidity all over the place this year, it is still flat. Note also that if you're using the torsion box approach, attached legs (even removable ones) are probably not necessary and a couple of appropriately shimmed sturdy sawhorses would probably do the trick (might be hard to level, though). Mine sits on a welded steel box-beam frame that I got at an auction for $40. I think it was a welding table or something. Anyways, it's very sturdy.
  8. Hi Kent. Welcome! There was a thread in this forum entitled "Canadian MARK IV Builders" a few months ago. Do a search on the forum and you should pick up quite a few leads. There are at least five builders in the Edmonton/Calgary area, most of whom (like me) are in the early stages. The Recreational AIrcraft Association (RAA) publishes a pretty good manual that details the Canadian aviation requirements for homebuilts. Check out www.raa.ca for details. I believe there is a fellow in Montreal who is flying a Cozy III, but other than that I don't know of any flying Canadian Cozy's. Dan Tomlinson on this forum seems to have pretty good handle on Canadian sources for materials. Others (like me) have used the US suppliers. Hope that helps, email me if you need more specific info on anything, Get ready to have tonnes of fun! Cheers, Trevor trevor@borialis.com
  9. This will probably only be of interest to brand-new builders/lurkers... Have seen in the archives/builder web sites several solutions to the problem of keeping your jig table level, usually using some variation of a nut+bolt embedded into the table leg. Happened to be browsing Lee Valley Tools (one of my favourite hangouts - if I had a gazillion bucks I would get at least one of everthing there... ). Saw these cool leg-leveller thingys that I will use for my table. They are rated at 2000lb apiece, and you can adjust them using a hex wrench from above. Plus, they have a rubber foot so if you need to move your table, you won't scuff up your floor. http://www.leevalley.com/hardware/page.asp?page=41865&category=3,40993,41283&abspage=1&ccurrency=2&SID=
  10. Due to the hassles of getting large stuff shipped up here to the Wilds of Canda, I've decided to get all the big and/or heavy stuff in one go. This means I wll potentially be storing some of my foam for a long time. Is there anything special I should to do to protect it? Will it age/get brittle/deform/develp surface irregularities etc? I am assuming the f/glass will be OK so long as I keep it clean and dry.
  11. After years of lurking, I'm about to get started! Just talked to Wicks, looks like the more stuff you get, the cheaper shipping is. Because of the size of some items (foam, longerons, etc), truck freight is the way to go, apparently. Are there any other builders in w. Canada (Edmonton/Calgary) who would like to order along w/me and save on the (probably) exorbitant shipping charges?
  12. Great idea to start a Canuck thread! I am in Edmonton, and while I have not yet begun to build, I expect to start in Spring '03, once I get my shop set up. Oh, and I guess acquiring a set of plans would be useful too... Nice to know there is another builder in Edmonton.
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