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Not much more progress made over the weekend - NFL Playoffs sucked the energy from me.
The next step of the build is to affix the leading edge. Now, I use a combination of CA and Wood Glues throughout my building. Anyplace I'm potentially going to sand almost always gets the Titebond. The leading edge is one of those places where I use Titebond instead of CA.
The method I used was to first dry-fit the LE onto the ribs. I clamped it on and marked where the glue went. I only did this on one side of the LE. Next, I unclamped and placed a bit of Titebond onto the bottom portion of the notch on each rib (see picture1). Next, I ran a small bead on the marked leading edge, replaced and clamped. Worked out well in my opinion - we'll see how much this pays off later when sheeting.
Whenever using CA, regardless of how careful I am, I always get the tip clogged. A little trick I learned here on RCU keeps me from getting too frustrated with that ... next time you're in the LHS, pickup some additional CA bottle tips and caps. While you're there, pickup some Acetone (local hardware store may have a better price). Next time your CA bottle tip clogs, don't throw it away. Unscrew it and toss it into a jar of Acetone. A few hours later and it's a good as new! I get in the habbit of cleaning my CA tips after every gluing session. I always keep some fresh (sealed) tips on-hand to seal my CA during the cleaning process - also keeps the air out. Which for some reason, I think is good.
Next up - Truing up the trailing edge sheeting.
Picture1 - Notch glued, notice mark on leading edge where I also glued Picture2 - Glogged CA tip Picture3 - Acetone Bath Picture4 - LE Secured and curing
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When I first looked at the steps for the wings in the manual, I thought to myself - not too bad, "I ought to blast through most of the upper wing in a few days". I should know better!
The first step on the trailing edge sheeting is to true up the edges and then cut them to 1". Now I know some guys that might skip this step thinking - "Hey, SIG's a great vendor, their wood is going to be straight and true - no need for me to waste time getting this puppy true..." Wrong Col. Sanders!!
Take a look at pictures1 and 2. This is the finished "trued" piece of sheeting directly from the kit. I about fell over when I held this against the straightedge - it looked like the lips of a smiley face! It was bowed that bad. I had to take pictures once I got it true. Picture1 is a measurement taken from the center and Picture2 is taken from the edge.
Of course, the second piece was virtually true to start with ... go figure.
Now that the sheeting is trued and cut its a matter of "glue and go", right? Well not in my case...
Now, I am about to show my anal retentive side - I'm feeling a bit vulerunable here - but this gives you a peek into my psyche.
The picture in the manual shows someone using Thin CA to affix the bottom section of the TE to the underside of the ribs - of course there's nothing holding this to the ribs ... at least nothing in the picture. So I think to myself, "how are you going to hold that TE sheeting onto the underhang of the ribs while at the same time gluing?". "Not well", was my answer!
So I came up with a cheesy solution - but it worked, so I can use it 2 more times (left and right wings)!
I figured, why not brace the sheeting from underneath? So I grabbed some scrap 1/4" balsa and fabricated 10 braces that fit under the TE sheeting and keeps it flush under the ribs. Brilliant, says the Guiness guy!
It ended up working better than I hoped. Since I used Titebond on this I weighted down the structure and grabbed an Adult Beverage
Picture1 - Trued piece; measurement at center Picture2 - Trued piece; measurement at end Picture3 - Fixture used to true edges - thanks Caffeenman! Picture4 - This is the brace I fabricated to keep the LE Sheeting flush under the Ribs Picture5 - Here you can see the little braces ready to be puched into place under the glued sheeting Picture6 - A closeup of the little brace at work
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The 1st step is admitting you have a problem ... okay, I admit it, RC is my obsession!
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Okay, the trailing edge sheeting is on. I read the next step about 50 times, looked at the plans and parts and even then couldn't bring myself to do what the directions were asking ...
The next step calls for sawing through the first 4 ribs all the way to the main spar. Check out Picture1, I outlined the portion that needs to be removed. This is an un-natural thing for this builder to do. After convincing myself that I could "fix it" if needed, I went ahead and cut out the material. Of course, this was the right thing to do, but it really felt awkward at the time.
It must be the day to get stumped - it was that way at work too . Anyway, the next step was the sheer webbing. Here's where I have to ask the Hog experts out there if this is right ...
It appears that there are only 4 sheer webs per wing 1/2 on the upper wing (Picture4). I am accustomed to putting sheer webbing across the entire wing, but it appears that the Hog doesn't need it?? Is this correct? Hopefully someone who's built this kit can weigh in. I went ahead and installed the 8 total sheer webs that I know are called for - they are curing at the moment.
I decided to look ahead and true up the leading edge sheeting for the next step. I couldn't believe how "un-true" this was. Now I've built my share of kits over the years and have never experienced this poor of a wood selection - this is not a knock on SIG as this can happen to anyone ... but geez. I tried to snap a picture of how bad this was. Check out Picture5. This is sitting as square as I could get it on my glass table top. Not only is it bent up and the ends, but its warped across the legnth. This piece may get tossed for a sample from my scrap building wood pile.
Picture1 - This is what needs to be removed from W-1T - scary Picture2 - Once the scrap is removed, the ply piece fits snug onto the bottom spar Picture3 - Starting to take shape Picture4 - Here are the Sheer Webs - only 4 per side on the Top Wing?? Is this right? Picture5 - Sheer Webbing clamped down and curing Picture6 - Picture doesn't do it justice - this was one "out of shape" piece of balsa
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The 1st step is admitting you have a problem ... okay, I admit it, RC is my obsession!
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Don't worry about removing the material from the ribs. The pieces that build it back up are ply and are much stronger in the end than a small piece of rib that was removed. It was designed this way. As far as the sheer webbing, no sweat there either. Adding sheer webbing to the outboard rib bays are just merely adding weight and add no beneficial strength. The ply spar along with the 4 sheer webs per wing halve give plenty of strength. Keep up the good work !
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Now that I'm comfortable with the build thus far - thanks again r2champion - the next step calls for sheeting the leading edge. Now I vented a bit in my last post about how poor the sheet stock was... In truing the sheet, I removed almost 1/4" of material. It made it so the sheet almost didn't reach the main spar. It did; barely (and I went back from underneath once I removed the wing from the board and further secured it). Check out Picture1 - do you guys think I ought to add some scrap sheeting to this and extend it to the trailing edge of the main spar?
I cut the cap strips out next. Not much to show here, really. Its a fairly simple step. Picture3 shows how I use my Exacto Blade to measure the proper length of balsa - hold it in place on the wing and press on the strip with the blade to make a small mark. Put the wood on a cutting surface and finish the cut - perfect fit every time .
By the way, you guys that have made multiple build threads (RCKen, Minn, etc.) - do you use some sort of tripod or something to get some of your shots? I need about 4 hands to accomplish some of the photography found in your builds. I've got a whole new respect for what it takes to document progress!
Once the cap strips were on and cured, I removed the wing and started on the underside. This is where additional strength is added to the center structure of the upper wing.
Next Step - Sheeting the lower portion of the wing (hopefully those pieces are a but more true to begin with)
Picture1 - Sheeting in place - there's not much sheeting to attach to the spar (there are NO gaps). Any reason to add some scrap sheeting here and extend to the trailing edge of the main spar? Picture2 - Picture of entire top wing after sheeting Picture3 - Marking length of cap strip. Picture4 - Assembled P-1 and B-2 installed and curing. NOTE: I epoxied the top assembly earlier and it is fully cured in this picture.
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The 1st step is admitting you have a problem ... okay, I admit it, RC is my obsession!
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All Forums >> RC Airplanes >> Kit Building >> RE: Sig Hog Bipe 
RE: Sig Hog Bipe - 
Got you building didn't I??? 
. Anyway, the next step was the sheer webbing. Here's where I have to ask the Hog experts out there if this is right ... 
I tried to snap a picture of how bad this was. Check out Picture5. This is sitting as square as I could get it on my glass table top. Not only is it bent up and the ends, but its warped across the legnth. This piece may get tossed for a sample from my scrap building wood pile. 
RE: Sig Hog Bipe -