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Section Hours: 116.2 Section Status: Complete



August 2, 2006: Today Angela & I plan to take care of the proseal duties on the elevators and the elevator trim tabs.  We'll basically be "gluing" in the foam ribs Angela cut out for us a while back, and the trailing edge wedges (just like in the rudder).


Proseal is actually a brand name, but it's the commonly accepted term for this stuff.  It was developed as a fuel tank sealant.  It's actually pretty impressive stuff.  Sticks very well but maintains a bit of flexibility after its cured.  We're using the stuff supplied by Van's: Part number MC-236-B2.  It's made by Flamemaster (part number CS 3204) and its very similar to Proseal.  In addition to Van's you can get this stuff at some of the tool suppliers we have listed on our links page, but if there are any industrial chemical suppliers in your area, check with them too.  Here you can see the curing agent.  This is mixed 1 part to 10 parts (by weight, not volume) with the white pasty looking stuff.  We bought a digital scale in order to do this.  Be sure and get one that is capable of reading down to a 10th of an ounce at a minimum.  That's how low ours goes, and I wish I had one that was even more sensitive.




Here's the paste part.  As you can see the can is a bit bigger.  Also note the Mickey Mouse dixie cups… a necessity for mixing this stuff!  (ok, maybe not the Mickey Mouse part -- it's all the store had available -- but you're going to want something disposable to mix it in)




Here I am mixing the 2 parts together.  Some people ratio these by the color.  I tried that the second time around and Angela pointed out that she thought I had too much…  she was right… I think I'll weigh it from now on.  Also, note in the pic the latex gloves.  These are a must also as there is basically no way to not get this stuff on at least some part of your hands.  And remember, it sticks VERY well!




(9-14 steps 8 & 9):  Ok, so now that the stuff is mixed up, these are my targets.  I made sure to have everything accessible prior to any mixing.  Here you can see the trim tabs with their corresponding foam ribs layed out in front of them.  And you can also see the elevators with their trailing edges spread apart with a piece of wood.  The trailing edge wedges that will be inserted are laying nearby also.




(9-17 step 9):  I think one of the most common applicators for proseal is a popsicke stick.  I couldn't find any at the store so I used a thin putty knife instead.  For the foam ribs I think it works better, but I didn't care to use it on the metal skins or trailing edges.  Here I'm applying a layer of proseal to one of the foam ribs that will go into the trim tab...




With the skins pried open on the trim tab I inserted the foam rib making sure to align it with the bare metal on the inside of the skin.




And here the first rib is inserted.  Only 2 more to go on this trim tab.  This is definitely easier to do as a 2 person job.  Not so much that there are 2 things to do, but invariably it'll happen that you need something moved or pulled out of the way, or shifted, and since your hands are sticky with proseal, its a good idea to have someone else use their CLEAN hands to do it!




(9-14 step 10, 9-17 step 10):  Well, our first mix job had enough to handle both trim tabs but only one of the elevators.  So, we went ahead and weighted down and secured everything on the parts that were sealed.  You want to make sure everything is held tightly in place while this stuff cures so you weight it down.  The trim tabs are placed in form blocks that are cut to shape.  These are placed directly over the location of the ribs in order to hald the skin flat against the ribs.  Once everything was secured we mixed up a second batch and finished the other elevator.  We then secured it, and called it a night.  Now these things will have to sit for a few days while we wait for this stuff to cure.
August 13, 2006 (9-14 steps 11 & 12):  Ahhh, its good to be back… way too long away from building!  First up, lets get some more done on these elevators.  I removed the clecoes from the trailing edges and then took a drill bit to clean the excess proseal out of the holes.  I then followed that up with a countersink bit to get the last bit around the edges of the dimples.  After that it was time to start riveting the trailing edes.  I inserted a rivet into every other hole, covered them with rivet tape, flipped the elevator over, and then 3/4 set the rivets in a more or less random order.  After that, I flipped the elevator back over, removed the tape, and then used a couple of small wood blocks I had laying around to clamp the trailing edge down firmly to the back riveting plate.  I then final set the rivet between the two blocks, and the ones exposed on either end only.  I would then unclamp, reposition and repeat.  All in all, it provided a relatively straight trailing edge.  No complaints here!








(9-15 steps 1 & 2):  Now that the trailing edges are done I squeezed the six remaining rivets attaching the skins to the outboard tip ribs on each elevator.  After that came the pop rivets attaching the shear clips to the close out tabs.
August 14, 2006 (9-18 steps 3 & 4):  Tonight I squared away the trim tab hinges.  I still had to match drill one of the hinge halves to the elevator itself.  After that the single hole drilled on the trim tab side of the hinge was used to secure one end of the trim tab.  I held the other end in place and match drilled a hole, clecoed it, and then continued with the other holes in a similar fashion.  After all the holes were drilled and clecoed I gave the tabs a couple of swings to check for any binding.




(9-18 steps 5 & 6):  Next I used the edges of the elevator and the trim tabs to mark the hinges.  They were then uninstalled, the pins removed, and the hinge halves were cut to their final shape. (the pins are not cut because they will be bent and secured along the rear spar later after they are permanantly installed)  I then deburred the edges and then reinstalled them to check the their fit… very nice.
August 17, 2006 (9-18 step 7):  Once home from work I wanted to concentrate on attaching the trim tabs to the elevators.  There seems to be some confusion as to whether the hinges supplied from Vans are anodized or not.  Vans says they are, but the part makings seemed to indicate they aren't.  So, I decided to use my alodine pen on the surfaces of them that will attach to the rear spar of the elevator (the remaining surfaces will be painted later).  So, while this stuff was drying I decided to sit down with a printout of the hinge spec and try and find out once and for all.  Well, in the hinge spec I did come across the statement that "designation for anodizing and length shall not be included in the marking"... that explains why the part markings don't indicate its anodized!




I wanted to use the squeezer when attaching the hinges.  In order to do that I needed a method for reaching around behind the eye loop of the hinge.  This is an idea I originally saw on Mike Howe's site.  I cut a small piece of steel off of our angle we've been using for trailing edges, deburred it and taped it to the yoke.




Here you can see the need for the modification.  Care must be taken to not hit the loops as they bend pretty easy.  Also, the plans call for AD3-4 rivets here.  These gauged about a 1/4 size to long.  Normally this isn't a problem, but with the squeezer mod being taped in place it was able to move when put under force so I wound up folding over 3 or 4 rivets.  The solution was to use AD3-3.5 rivets (about a 1/4 size too short) and I also epoxied the mod on the yoke (it was popped off later with a pair of pliers).  Worked great!






(9-18 step 8):  After the hinges were attached the trim tabs were connected to the elevators with their pins.  I began bending the pin on one of them… they don't bend that easy.  Well, it's getting kind of late so I'll finish this up tomorrow…
August 18, 2006 (9-19 steps 1 & 2):  First thing is to finish bending these hinge pins.  These things are bent so that the inboard end lays flat against the rear spar.  Once I had the shape right I drilled the small hole in the rear spar that will be used to safety wire these pins to the spar.  I've got the safety wire, but I'm going to hold off on attaching these things for now because they'll just flop around too much while we're moving them around.  Oh, I dabbed a bit of our alodine 1132 pen in the holes for some protection on the newly exposed aluminum also.




(9-15 step 3):  I put the slight bend in the upper leading edge skin of the right elevator (the left one was done a while ago).  We're going to hold off on rolling the leading edges until after our tech advisor has a look at everything.


(9-15 step 8):  I also started cutting the lead counterweights to their final shape.  Angela arrived home while I was doing this so I cut it off here for the night.  Will continue tomorrow.
August 19, 2006 (9-15 step 8):  Not really wanting to mess with the lead, but motivated by getting this step done!... I finished trimming up the lead counterbalance weights.  I didn't really get very far with them yesterday.  There are 4 of these guys, all cut to the same shape.  On one side of the weights there is a raised portion which has to be removed from two of them.  Once this portion is cut off these two weights become the inboard weights, the other two the outboard.  Ok... so initially I thought I'd cut the weights with the band saw.  Turns out the speed of the blade is too fast and the lead heats up pretty quick!  I needed something slower... hey... I'm slow... thats it... I'll cut it by hand... ugh!  After the the ends were cut off I used the belt sander to smooth the cut ends down a little bit (a hack saw and lead makes for an UGLY surface)  Once the final shape was formed, I clamped two of them in the bench vise and started working on removing the raised portion.  After that was removed I filed the rough surface flat.  And that was it... I'm glad thats over!
August 20, 2006 (9-15 step 9):  This morning I'm going to try and squeeze in a little shop time before church… so lets see about attaching the counterbalance weights.  The holes in the weights needed to be opened up a little bit.  After that the weights were attached to the counterbalance ribs (one inboard, one outboard) and the AN hardware installed.  Once in place the nuts were torqued to 25 in-lb.
August 27, 2006:  We're basically done with the elevators.  We're holding off rolling & closing up the leading edge until our first tech counselor visit.  Probably don't need to, but would like for him to peer in and check things out.  Since we've still got some busy work left on the elevators we're also waiting to safety-wire the trim tabs on.  So... for now, the elevators are back 'On Hold'.
January 24, 2007:  Time to get back to work on the elevators :-)  Ahhh yes… I remember these things ;-)  Well, I finally decided its time to close the leading edges on them.  I don't have time tonight, but felt the need to do something.  So, I went ahead and scuffed the porton of the lower skin that will be overlapped by the upper, cleaned it, and then alodined it with the Alodine pen.
January 26, 2007 (9-10 step 1):  Overkill time again!  Prior to closing up the elevators I mixed up a bit of primer and brushed it on all the rivets that'll be covered up by the leading edges.  The idea is that since there are openings in the leading edges, water can get in, whether it be while washing the plane, flying through a bit of rain, whatever.  And, its easy enough to do now, so why not!  If it wasn't green before, it is now :-)




(9-15 step 4):  The elevators are a bit longer than the rudder… didn't realize it at the time we bought the pipe to roll the rudder leading edge or else we would've gotten it a foot longer.  So, I wound up getting a 6' long pipe, 3/4" in diameter this time.  We went one section of the elevator at a time like on the rudder and one of us would roll the pipe while the other was keeping pressure down on the opposite end.  The rolls went quicker this way, and since the pipe was such a small diameter, it only took one quick roll, and the bend was done.  The 3/4" is a bit too small of a diameter however... I wouldn't recommend it... I had to "massage" each bend by hand to get it to fit.  So, not our prettiest rolled leading edges, but it'll work.  Anyway, the right one is all rolled and clecoed together.  Now on to the left.






(9-15 steps 5 & 6):  Staying up a little past my bed time, I decided I wanted these elevators done!  So, we needed to get the left one up to speed… I'd set up, Angela would come over and help me roll, I'd massage it to fit, and then we'd repeat until all the sections were done.  I then used the same technique I did for the rudder to final drill all the holes, only unclecoing one hole at a time.  A reamer really works well here since you can't really debut your holes too well, and a reamer leaves far less bur to remove than a drill bit.  After they were all final drilled, out came the pop riveter, and that's it... the elvators are DONE!


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