Pay It Forward Build Thread!! Sig LT-40 build
#277
RE: Pay It Forward Build Thread!! Sig LT-40 build
Finally made it back to getting my progress posted here in the build thread. So let's jump back in and see how things are going. In my last progress report I had started gluing the fuselage together by gluing former F2 in place.
Next according to the instructions is to glue the firewall in place. Once again I disagree with the instructions here. They call for using CA to glue in the firewall. Please DO NOT do this. Remember, the firewall is the part that connects your engine to your plane. Every bit of force generated by your engine will pull directly on the firewall, therefore you are going to want your firewall to be attached to the rest of the fuselage as securely as possible. I use 30 minute epoxy to glue the firewall in place. Picture #1 shows the prep for gluing the firewall in place. Mix up a little bit of 30 minute epoxy, you won't need very much so don't go overboard with how much you mix. When you have the epoxy mixed used a craft stick to spread the epoxy along the edges of of the firewall (picture #2). Make sure that you have the epoxy spread evenly along the edge of the firewall, and make sure you have no gaps or spots missing epoxy on them. When you put the firewall in place in the fuselage sides make sure that you have the firewall properly oriented, with the front and top of the firewall properly positioned. I used a couple of quick clamps to hold the fuselage together while the epoxy set (picture #3). Make sure you don't disturb the fuselage while the epoxy is setting. You want to make sure the bond between the fuselage and the firewall is as secure and strong as you can get it.
After the firewall is set it's time to move on to finish gluing the rest of the formers in place. Since I am using wood glue for assembly I've got time to proceed with this step. I can loosen up the rubberbands and lift each former to apply glue to them, and then replace the rubberbands. Since the glue as a setting time of approximately 30 minutes I can do all of the formers and then set the fuselage aside to set. Pictures #4 and #5 show putting glue on each former. As I stated above, if you have all of the fuselage parts in place while you are gluing the fuselage will come out straight and square. If you try to glue the fuselage with parts missing you are running a great chance of having your fuselage come out crooked. With this in mind I make sure everything is in place and then I set the fuselage to let the glue dry. In picture #6 you can see that I used scrap wood to block up the rear of fuselage and then placed weights on the fuselage (picture #7) to hold the fuselage while the glue sets. I did this because the width of the fuselage decreases towards the tail of the airplane, and blocking up the fuselage helps to make sure the fuselage will stay straight and square.
Note: If you are using CA to glue the fuselage together you will do the assembly a bit differently. You will need to make sure that all of the fuselage parts are in place, and that it is held together with rubberbands. Then use CA to wick into the joints between the formers and the fuselage sides. Make sure that you give it plenty of time to set before moving along. Try not to get in a hurry and use accelerator to set you CA. It can sometimes make the CA brittle and you don't want that to happen here on the fuselage.
With the fuselage formers now glued to the fuselage sides it's time to start gluing in the top and bottom pieces of the fuselage. We'll start with the FB-F (Fuselage Bottom-Front) piece. Test fit the part to make sure that it fits tightly and securely in place. Look at the places where the tabs of the part will fit with the fuselage. In picture #8 I used an emory board to file down the tab location so that it is flush with the bottom of the firewall and former F2 (picture #9). Run a bead of glue around where the part will sit (picture #10), and place the part in place. To make it a bit easier for me to put the part in place once I glued it I pulled all of the rubberbands further down the fuselage as shown in picture #11. Once the bottom piece is in place I slid the rubberbands back into place and used weights to hold the part in place while the glue set (picture #12). Once again, as long as all the fuselage parts (even the ones not glued yet) are in place the fuselage will be straight and square.
I know that what I have said here sounds like this part doesn't take long, but trust me, you don't want to get in a rush here. Building a straight and true fuselage will result in a better flying airplane. The plane can still fly straight if the fuselage is crooked by adjusting the flight with your trims, but it's much better if you don't have to do this. Take your time and build the fuselage straight and true, you'll enjoy the plane more in the end.
Pictures
1. Preparing to glue the firewall in place.
2. Applying epoxy to the firewall sides.
3. Clamp the firewall in place while the epoxy sets.
4. Apply glue to the remainder of the fuselage formers.
5. Apply glue to the remainder of the fuselage formers.
6. Block the rear of the fuselage up while the glue sets.
7. Use weights to while the glue sets.
8. File down so fuselage bottom fits better.
9.Tab slot is flush with the bottom of the firewall.
10. Apply glue for fuselage bottom.
11. Pull rubberbands back in order to place fuselage bottom.
12. Use weight to hold fuselage bottom in place while glue dries.
Until next time
Ken
Next according to the instructions is to glue the firewall in place. Once again I disagree with the instructions here. They call for using CA to glue in the firewall. Please DO NOT do this. Remember, the firewall is the part that connects your engine to your plane. Every bit of force generated by your engine will pull directly on the firewall, therefore you are going to want your firewall to be attached to the rest of the fuselage as securely as possible. I use 30 minute epoxy to glue the firewall in place. Picture #1 shows the prep for gluing the firewall in place. Mix up a little bit of 30 minute epoxy, you won't need very much so don't go overboard with how much you mix. When you have the epoxy mixed used a craft stick to spread the epoxy along the edges of of the firewall (picture #2). Make sure that you have the epoxy spread evenly along the edge of the firewall, and make sure you have no gaps or spots missing epoxy on them. When you put the firewall in place in the fuselage sides make sure that you have the firewall properly oriented, with the front and top of the firewall properly positioned. I used a couple of quick clamps to hold the fuselage together while the epoxy set (picture #3). Make sure you don't disturb the fuselage while the epoxy is setting. You want to make sure the bond between the fuselage and the firewall is as secure and strong as you can get it.
After the firewall is set it's time to move on to finish gluing the rest of the formers in place. Since I am using wood glue for assembly I've got time to proceed with this step. I can loosen up the rubberbands and lift each former to apply glue to them, and then replace the rubberbands. Since the glue as a setting time of approximately 30 minutes I can do all of the formers and then set the fuselage aside to set. Pictures #4 and #5 show putting glue on each former. As I stated above, if you have all of the fuselage parts in place while you are gluing the fuselage will come out straight and square. If you try to glue the fuselage with parts missing you are running a great chance of having your fuselage come out crooked. With this in mind I make sure everything is in place and then I set the fuselage to let the glue dry. In picture #6 you can see that I used scrap wood to block up the rear of fuselage and then placed weights on the fuselage (picture #7) to hold the fuselage while the glue sets. I did this because the width of the fuselage decreases towards the tail of the airplane, and blocking up the fuselage helps to make sure the fuselage will stay straight and square.
Note: If you are using CA to glue the fuselage together you will do the assembly a bit differently. You will need to make sure that all of the fuselage parts are in place, and that it is held together with rubberbands. Then use CA to wick into the joints between the formers and the fuselage sides. Make sure that you give it plenty of time to set before moving along. Try not to get in a hurry and use accelerator to set you CA. It can sometimes make the CA brittle and you don't want that to happen here on the fuselage.
With the fuselage formers now glued to the fuselage sides it's time to start gluing in the top and bottom pieces of the fuselage. We'll start with the FB-F (Fuselage Bottom-Front) piece. Test fit the part to make sure that it fits tightly and securely in place. Look at the places where the tabs of the part will fit with the fuselage. In picture #8 I used an emory board to file down the tab location so that it is flush with the bottom of the firewall and former F2 (picture #9). Run a bead of glue around where the part will sit (picture #10), and place the part in place. To make it a bit easier for me to put the part in place once I glued it I pulled all of the rubberbands further down the fuselage as shown in picture #11. Once the bottom piece is in place I slid the rubberbands back into place and used weights to hold the part in place while the glue set (picture #12). Once again, as long as all the fuselage parts (even the ones not glued yet) are in place the fuselage will be straight and square.
I know that what I have said here sounds like this part doesn't take long, but trust me, you don't want to get in a rush here. Building a straight and true fuselage will result in a better flying airplane. The plane can still fly straight if the fuselage is crooked by adjusting the flight with your trims, but it's much better if you don't have to do this. Take your time and build the fuselage straight and true, you'll enjoy the plane more in the end.
Pictures
1. Preparing to glue the firewall in place.
2. Applying epoxy to the firewall sides.
3. Clamp the firewall in place while the epoxy sets.
4. Apply glue to the remainder of the fuselage formers.
5. Apply glue to the remainder of the fuselage formers.
6. Block the rear of the fuselage up while the glue sets.
7. Use weights to while the glue sets.
8. File down so fuselage bottom fits better.
9.Tab slot is flush with the bottom of the firewall.
10. Apply glue for fuselage bottom.
11. Pull rubberbands back in order to place fuselage bottom.
12. Use weight to hold fuselage bottom in place while glue dries.
Until next time
Ken
#281
My Feedback: (32)
RE: Pay It Forward Build Thread!! Sig LT-40 build
ORIGINAL: RCKen
[:@]
Fly?? Fly!!! Nobody told me it had to fly!!!! [X(]
Ken
ORIGINAL: Lightfoot
I'm just hoping this plane will actually fly when Ken gets it done.
I'm just hoping this plane will actually fly when Ken gets it done.
Fly?? Fly!!! Nobody told me it had to fly!!!! [X(]
Ken
HAW HAW
Don't worry SeaBee1, I'm just kidding with Ken.
#282
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RE: Pay It Forward Build Thread!! Sig LT-40 build
ORIGINAL: bubbagates
Is that why you are using epoxy on everyting Or are you just trying to make it really really strong. Hopefully you did not use the wood that came with it and went to Lowes and Home Depot for the "good stuff"
HAW HAW
Don't worry SeaBee1, I'm just kidding with Ken.
ORIGINAL: RCKen
[:@]
Fly?? Fly!!! Nobody told me it had to fly!!!! [X(]
Ken
ORIGINAL: Lightfoot
I'm just hoping this plane will actually fly when Ken gets it done.
I'm just hoping this plane will actually fly when Ken gets it done.
Fly?? Fly!!! Nobody told me it had to fly!!!! [X(]
Ken
HAW HAW
Don't worry SeaBee1, I'm just kidding with Ken.
#283
RE: Pay It Forward Build Thread!! Sig LT-40 build
You don't think anyone would be silly enough to use Home Depot plywood do you?
That would make as much sense as stomping on your plane and expecting it to fly!
That would make as much sense as stomping on your plane and expecting it to fly!
#284
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RE: Pay It Forward Build Thread!! Sig LT-40 build
ORIGINAL: bruce88123
You don't think anyone would be silly enough to use Home Depot plywood do you?
That would make as much sense as stomping on your plane and expecting it to fly!
You don't think anyone would be silly enough to use Home Depot plywood do you?
That would make as much sense as stomping on your plane and expecting it to fly!
(I was starting to miss my hat!)
#285
My Feedback: (32)
RE: Pay It Forward Build Thread!! Sig LT-40 build
ORIGINAL: bruce88123
That would make as much sense as stomping on your plane and expecting it to fly!
That would make as much sense as stomping on your plane and expecting it to fly!
Someone better PM SeeBee and explain to him what we are talking about
#289
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RE: Pay It Forward Build Thread!! Sig LT-40 build
No answer to the Christmas Tree ?? huh? You'd think the guy had to run a business, moderate a forum, keep up with a build thread while building an airplane, take care of his family, & still fly his own planes! What do you do with all that spare time on your hands anyway?
Mark
Mark
#290
RE: Pay It Forward Build Thread!! Sig LT-40 build
ORIGINAL: elenasgrumpy
What do you do with all that spare time on your hands anyway?
Mark
What do you do with all that spare time on your hands anyway?
Mark
It's possible that I might get it finished before Christmas, but I'm not going to hold my breath. A conservative guess is that it will probably take about a week just to cover it. Since we only have 2 weeks left before christmas that doesn't leave me much time to get it shipped to him!!!
A good guess is that he should have it sometime in the first part of next month
Ken
#293
RE: Pay It Forward Build Thread!! Sig LT-40 build
I'll let everybody in on a little secret. I'm actually further on in the build than I have posted here. Bruce, don't say it. I know that you already had that figured out. But what can I say?? I'm human! I think I said this earlier in this thread, I had no idea how much work this was. I have a new found respect of anybody who is a technical writer and does this for a living!! Anyway, let's get more information posted.
In my last post we glued on the FB-F (Fuselage Bottom – Front). Now we're ready to move on do doing the FB-R (Fuselage Bottom – Rear). Just like we did on the last step, I'm going to remove the FB-R part so that I can get glue applied to the joint. Pictures #1 and #2 show that I've pulled the rubberbands out of the way so that I can easily remove and replace the fuselage bottom. Also, as we did before we need to make sure that the parts fit together properly. I can't even count how many times I have seen people just pull the parts out of the box and glue them in place. This is where a lot of people make mistakes, and they wind up with a weak built plane. If you take the time to dress up the parts and make sure that they have proper wood to wood contact you will be rewarded in the end with a high quality built plane. The best and strongest joint you can have will be a wood to wood joint, any gaps between the wood will result in a weak joint-- no matter how much or what type of glue you use. Just like before, we want to make sure that the tab joints fit to the top of the formers (pictures #3 and #4). Use an emery board or a sanding block to make sure everything fits properly. Once we're happy with the fit of the part go ahead and apply the glue to the where the part will sit. In picture #5 I'm repositioning the rubberbands to hold the part in place. Because of the way that the part fit I had to secure it a little differently this time, instead of using weights on top of the part I needed to use clamps to hold it all in place while the glue dried (picture #6 and #7). Like before, if you are using CA adhesive you will clamp everything in place and then wick thin CA into the joints where the wood meets. Although an even better way would be to work the parts the same way that I am, spread thick CA instead of the wood glue I use, and clamp and hold the parts in the same fashion I did. For future posts I'm not going to lay how to work the parts with CA, but since I've covered it those using CA should have a good idea of how to proceed. If you have any questions about it please feel free to PM me and I'll see if I can help you out.
After doing the the fuselage bottom we'll move on to doing the fuselage top. I'm not going to spend a lot of time writing about how I did these parts because they are done exactly like the last two posts, so I'll just touch on the fact that they need to be done. I've included pictures #8 and #9 to so a couple of building techniques that I haven't mentioned before. When you place the part in place take a few seconds and wipe any excess glue that has seeped up. When the glue is forced out of joints like this you have to deal with the excess glue at some point, either wiping it off when it's wet or sanding it off after it dries, and since it's easier to get off while it's wet I take the extra time to clean up as I go. In fact, I buy paper towels at Sam's Club and get the bulk discount. They are one item that any builder should use a lot of. So it helps to stock up. Anyway, picture #10 shows the FT-R in place and clamped for the glue to dry. Picture #11 shows the part F8 in place and clamped while the glue dries.
Pictures
1. Fuselage bottom removed so glue can be applied to the joints
2. Moving the rubberbands out of the way in order to remove and replace fuselage bottom.
3. Dressing up the joints so that the fuselage bottom fits better
4. Make sure the bottom will be in contact with the bottom of the fuselage former.
5. Moving the rubberbands back in place after the part is glued in place.
6. The fuselage bottom in place and clamped while the glue dries.
7. Keeping the fuselage bottom secure while the glue dries
8. Putting the fuselage top in place.
9. Wiping away any excess glue.
10. Clamping the fuselage top in place while the glue dries.
11. Clamping the F8 piece in place while the glue dries.
Until next time
Ken
In my last post we glued on the FB-F (Fuselage Bottom – Front). Now we're ready to move on do doing the FB-R (Fuselage Bottom – Rear). Just like we did on the last step, I'm going to remove the FB-R part so that I can get glue applied to the joint. Pictures #1 and #2 show that I've pulled the rubberbands out of the way so that I can easily remove and replace the fuselage bottom. Also, as we did before we need to make sure that the parts fit together properly. I can't even count how many times I have seen people just pull the parts out of the box and glue them in place. This is where a lot of people make mistakes, and they wind up with a weak built plane. If you take the time to dress up the parts and make sure that they have proper wood to wood contact you will be rewarded in the end with a high quality built plane. The best and strongest joint you can have will be a wood to wood joint, any gaps between the wood will result in a weak joint-- no matter how much or what type of glue you use. Just like before, we want to make sure that the tab joints fit to the top of the formers (pictures #3 and #4). Use an emery board or a sanding block to make sure everything fits properly. Once we're happy with the fit of the part go ahead and apply the glue to the where the part will sit. In picture #5 I'm repositioning the rubberbands to hold the part in place. Because of the way that the part fit I had to secure it a little differently this time, instead of using weights on top of the part I needed to use clamps to hold it all in place while the glue dried (picture #6 and #7). Like before, if you are using CA adhesive you will clamp everything in place and then wick thin CA into the joints where the wood meets. Although an even better way would be to work the parts the same way that I am, spread thick CA instead of the wood glue I use, and clamp and hold the parts in the same fashion I did. For future posts I'm not going to lay how to work the parts with CA, but since I've covered it those using CA should have a good idea of how to proceed. If you have any questions about it please feel free to PM me and I'll see if I can help you out.
After doing the the fuselage bottom we'll move on to doing the fuselage top. I'm not going to spend a lot of time writing about how I did these parts because they are done exactly like the last two posts, so I'll just touch on the fact that they need to be done. I've included pictures #8 and #9 to so a couple of building techniques that I haven't mentioned before. When you place the part in place take a few seconds and wipe any excess glue that has seeped up. When the glue is forced out of joints like this you have to deal with the excess glue at some point, either wiping it off when it's wet or sanding it off after it dries, and since it's easier to get off while it's wet I take the extra time to clean up as I go. In fact, I buy paper towels at Sam's Club and get the bulk discount. They are one item that any builder should use a lot of. So it helps to stock up. Anyway, picture #10 shows the FT-R in place and clamped for the glue to dry. Picture #11 shows the part F8 in place and clamped while the glue dries.
Pictures
1. Fuselage bottom removed so glue can be applied to the joints
2. Moving the rubberbands out of the way in order to remove and replace fuselage bottom.
3. Dressing up the joints so that the fuselage bottom fits better
4. Make sure the bottom will be in contact with the bottom of the fuselage former.
5. Moving the rubberbands back in place after the part is glued in place.
6. The fuselage bottom in place and clamped while the glue dries.
7. Keeping the fuselage bottom secure while the glue dries
8. Putting the fuselage top in place.
9. Wiping away any excess glue.
10. Clamping the fuselage top in place while the glue dries.
11. Clamping the F8 piece in place while the glue dries.
Until next time
Ken
#295
RE: Pay It Forward Build Thread!! Sig LT-40 build
Actually, I expect Ken will get it out on time. Just no need to rush a nice project, like we tell all of the other builders.
#296
RE: Pay It Forward Build Thread!! Sig LT-40 build
ORIGINAL: bruce88123
Actually, I expect Ken will get it out on time. Just no need to rush a nice project, like we tell all of the other builders.
Actually, I expect Ken will get it out on time. Just no need to rush a nice project, like we tell all of the other builders.
Ken
#298
My Feedback: (32)
RE: Pay It Forward Build Thread!! Sig LT-40 build
ORIGINAL: RCKen
Does that mean that I can't have the wing build 3 hours after the kit is delivered?? [X(] [>:] [&o]
Ken
ORIGINAL: bruce88123
Actually, I expect Ken will get it out on time. Just no need to rush a nice project, like we tell all of the other builders.
Actually, I expect Ken will get it out on time. Just no need to rush a nice project, like we tell all of the other builders.
Ken
#299
RE: Pay It Forward Build Thread!! Sig LT-40 build
To carry on and wrap up the largest part of the fuselage build. We have the largest part of the fuselage built, but I like to go back and ensure that the glue joints are strong. I do that by laying a bead of glue into the joints of the fuselage. Before I go any further we need to talk about this for a bit. Doing this step has pros and some serious cons to it. The biggest thing that you need to realize is that not all glues are suited to do this with. Different glues weigh differently. Some glues can give you a lot of strength yet add very little weight to the overall plane. While others (epoxy especially) will add a lot of weight. I've seen one plane that was built where the builder used epoxy on ALL of the joints in the fuselage. Yes, the fuselage was strong enough to use as a baseball bat, but it also weighed more than a wheelbarrel of bricks. If you don't know if your adhesive adds weight then by all means please ask here on RCU. Glues like epoxy and thick CA are very strong, but they also add a lot of weight. While on the other end of the spectrum wood glue also adds lots of strength, but weighs next to nothing when dry. (in case you wonder why, it's because most wood glues are water based. When the glue dries the water evaporates out of the glue. As much as 90% of the original weight of the glue is gone after it dries). This is another reason why I prefer to use wood glue to build with.
With the above information in mind, I decided to go back to all of the joints and lay down a bead of wood glue in each joint to help strengthen the joint. Normally I don't do this when I build a plane, but because of the intended use of this plane I rethought that decision. Because this plane is going to be a trainer and will have at least 3 people (SeaBee1 and his 2 daughters) learning on it, I know it's going to get a lot of use. Because of that I want the fuselage to be as strong as possible. I want to make a quick note on pictures #2 and #3 before some eagle eye out there calls me on it. Yes, the picture does show parts of the fuselage that I have already glued on in earlier steps. I put down the bead of glue and took the pictures as I assembled the plane so that I could get better pictures of my work. So yes, those parts should be in place!! . With that said, picture #1 shows what our fuselage should look like right now. The rest of the pictures show putting down a bead of glue in all of the joints of the plane. Some of my pictures show HUGE amounts of glue being used. Once again, for example. You don't need that much glue. After laying down that much glue I will run my finger over the joint to wipe excess glue away. After you have a bead of glue in each joint take a break and let the glue dry before we move on.
Pictures
1. Fuselage assembled up to this point.
2. Joint with a bead of glue for extra strength.
3. Laying down a bead of glue in joints of the fuselage.
4. Joint with a bead of glue for extra strength.
5. Joint with a bead of glue for extra strength.
6.Laying down a bead of glue in joints of the fuselage.
7.Joint with a bead of glue for extra strength.
Until next time
Ken
With the above information in mind, I decided to go back to all of the joints and lay down a bead of wood glue in each joint to help strengthen the joint. Normally I don't do this when I build a plane, but because of the intended use of this plane I rethought that decision. Because this plane is going to be a trainer and will have at least 3 people (SeaBee1 and his 2 daughters) learning on it, I know it's going to get a lot of use. Because of that I want the fuselage to be as strong as possible. I want to make a quick note on pictures #2 and #3 before some eagle eye out there calls me on it. Yes, the picture does show parts of the fuselage that I have already glued on in earlier steps. I put down the bead of glue and took the pictures as I assembled the plane so that I could get better pictures of my work. So yes, those parts should be in place!! . With that said, picture #1 shows what our fuselage should look like right now. The rest of the pictures show putting down a bead of glue in all of the joints of the plane. Some of my pictures show HUGE amounts of glue being used. Once again, for example. You don't need that much glue. After laying down that much glue I will run my finger over the joint to wipe excess glue away. After you have a bead of glue in each joint take a break and let the glue dry before we move on.
Pictures
1. Fuselage assembled up to this point.
2. Joint with a bead of glue for extra strength.
3. Laying down a bead of glue in joints of the fuselage.
4. Joint with a bead of glue for extra strength.
5. Joint with a bead of glue for extra strength.
6.Laying down a bead of glue in joints of the fuselage.
7.Joint with a bead of glue for extra strength.
Until next time
Ken
#300
RE: Pay It Forward Build Thread!! Sig LT-40 build
For those of you following this thread, PLEASE understand that some of the last few comments by Ken, Bubba and myself were meant as inside jokes and not actual building advice. Please follow all instructions and build on a proper table/surface. We now return sanity to the thread. [sm=bananahead.gif] Well, sort of anyway.