Building a scale 1/4 scale Super Cub from Balsa J3 kit
#451
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Well, let me count the ways! LOL! And this is strictly my own rigid opinion! I just don't use the yellow or white and I don't see any advantage that yellow or white glue had over CA. I have become accustom to the fast curing of the CA. I have never had a catastrophic failure because of CA. There is no accelerator for yellow or white glue and CA doesn't have to be pinned down to dry with the possibility of something popping up! Building time is increased ten fold if not more!
Now, having said that, Yellow and white glue does have an advantage over CA when it comes to building cabinets and other furniture and things of that sort where I have found that CA doesn't hold up in that area unless it is a small project and not under a great deal of strain like the afore mentioned.
When I said what I said about epoxy's and the differences, five minute especially, just to address John M.'s comment. I have seen many failures because of it's lack of penetration. When fuel gets on or in and around it, it will, in time, peal off of the wood. You can usually tell when it is five minute because it will be a dark amber color.
I probably wouldn't use it as a field repair either because you will inevitably have the same results of limited adhesion. I would rather use CA for a field repair if I had the choice and in many cases, thin would work very well if the parts have not separated and medium if they have. Many models I have built, the firewall was installed with medium CA with triangle stock behind it. I would use this up to a sixty size ship and if I went any bigger, I would dowel the firewall if I used CA. I am very confident in it's reliability and strength. I have 'tested' it many times!!!!! and what you might think would fail, didn't. If it did fail, there was very evident adhesion because of the wood tearing out and not failing at the joint.
It's a matter of choice as a few have pointed out thus far and I totally agree. I would almost bet that Dave Platt and Frank Tiano use CA in their building quite extensively and they are prolific big ship builders. Not to mention, they are quite opinionated just like me!LOL!
Anyway, that is my take on it. Like I said, I can be quite pig headed when I think I'm right! I'm sure none of you guys are like that so that leaves me in a class by my self! LOL!
God it's lonely up here! LOL! Use your shot gun and shoot some of my balloons so I can come back to the ground would ya?
Thanks guys for putting up with me.
Your bud
bird. .............................really!
Now, having said that, Yellow and white glue does have an advantage over CA when it comes to building cabinets and other furniture and things of that sort where I have found that CA doesn't hold up in that area unless it is a small project and not under a great deal of strain like the afore mentioned.
When I said what I said about epoxy's and the differences, five minute especially, just to address John M.'s comment. I have seen many failures because of it's lack of penetration. When fuel gets on or in and around it, it will, in time, peal off of the wood. You can usually tell when it is five minute because it will be a dark amber color.
I probably wouldn't use it as a field repair either because you will inevitably have the same results of limited adhesion. I would rather use CA for a field repair if I had the choice and in many cases, thin would work very well if the parts have not separated and medium if they have. Many models I have built, the firewall was installed with medium CA with triangle stock behind it. I would use this up to a sixty size ship and if I went any bigger, I would dowel the firewall if I used CA. I am very confident in it's reliability and strength. I have 'tested' it many times!!!!! and what you might think would fail, didn't. If it did fail, there was very evident adhesion because of the wood tearing out and not failing at the joint.
It's a matter of choice as a few have pointed out thus far and I totally agree. I would almost bet that Dave Platt and Frank Tiano use CA in their building quite extensively and they are prolific big ship builders. Not to mention, they are quite opinionated just like me!LOL!
Anyway, that is my take on it. Like I said, I can be quite pig headed when I think I'm right! I'm sure none of you guys are like that so that leaves me in a class by my self! LOL!
God it's lonely up here! LOL! Use your shot gun and shoot some of my balloons so I can come back to the ground would ya?
Thanks guys for putting up with me.
Your bud
bird. .............................really!
Last edited by bigbird3; 12-24-2014 at 09:50 PM.
#452
Thread Starter
One thing it's lighter after it dries, allows more time to adjust a part if needed as well as makes a strong joint with any wood, being water based it has good penetration in the fibers of wood and in spite of what some say it does not deteriorate over time if kept in a controlled environment like your home. Tightbond 11 and 111 have inhibitors for wet climates but don't use it for under water applications. It is easier to sand when doing laminates, fillets and the like.
There is nothing wrong with CA glues and is a strong bonding agent for many items except plastics which it will eat into it. Balsa is a wonder wood with a mix of densities and fibers, the inner tree parts have the hardest and most dense fibers, most of which are hard and long, as you move out in the growth rings (hardly visible) it loses density and has more soft fibers than hard ones hence the saying, the whiter the lighter and all glues bond well to it if dust free. .
While there is many glues that can be used for building our balsa planes the ones I mentioned are the most common I believe. Plywood is often very hard (not speaking of light-ply) and has a slick surface making bonding difficult with the exception of contact cement, the surface in most cases needs to be roughed up good so the glue has something to grab on to, epoxy is a good one for that kind of gluing.
I have been building with wood for years and have never had a glue joint fail in any of it, it boils down to the type of glue used and the kind of wood glued, our planes are no different.
Leroy
There is nothing wrong with CA glues and is a strong bonding agent for many items except plastics which it will eat into it. Balsa is a wonder wood with a mix of densities and fibers, the inner tree parts have the hardest and most dense fibers, most of which are hard and long, as you move out in the growth rings (hardly visible) it loses density and has more soft fibers than hard ones hence the saying, the whiter the lighter and all glues bond well to it if dust free. .
While there is many glues that can be used for building our balsa planes the ones I mentioned are the most common I believe. Plywood is often very hard (not speaking of light-ply) and has a slick surface making bonding difficult with the exception of contact cement, the surface in most cases needs to be roughed up good so the glue has something to grab on to, epoxy is a good one for that kind of gluing.
I have been building with wood for years and have never had a glue joint fail in any of it, it boils down to the type of glue used and the kind of wood glued, our planes are no different.
Leroy
#453
One thing it's lighter after it dries, allows more time to adjust a part if needed as well as makes a strong joint with any wood, being water based it has good penetration in the fibers of wood and in spite of what some say it does not deteriorate over time if kept in a controlled environment like your home. Tightbond 11 and 111 have inhibitors for wet climates but don't use it for under water applications. It is easier to sand when doing laminates, fillets and the like.
There is nothing wrong with CA glues and is a strong bonding agent for many items except plastics which it will eat into it. Balsa is a wonder wood with a mix of densities and fibers, the inner tree parts have the hardest and most dense fibers, most of which are hard and long, as you move out in the growth rings (hardly visible) it loses density and has more soft fibers than hard ones hence the saying, the whiter the lighter and all glues bond well to it if dust free. .
While there is many glues that can be used for building our balsa planes the ones I mentioned are the most common I believe. Plywood is often very hard (not speaking of light-ply) and has a slick surface making bonding difficult with the exception of contact cement, the surface in most cases needs to be roughed up good so the glue has something to grab on to, epoxy is a good one for that kind of gluing.
I have been building with wood for years and have never had a glue joint fail in any of it, it boils down to the type of glue used and the kind of wood glued, our planes are no different.
Leroy
There is nothing wrong with CA glues and is a strong bonding agent for many items except plastics which it will eat into it. Balsa is a wonder wood with a mix of densities and fibers, the inner tree parts have the hardest and most dense fibers, most of which are hard and long, as you move out in the growth rings (hardly visible) it loses density and has more soft fibers than hard ones hence the saying, the whiter the lighter and all glues bond well to it if dust free. .
While there is many glues that can be used for building our balsa planes the ones I mentioned are the most common I believe. Plywood is often very hard (not speaking of light-ply) and has a slick surface making bonding difficult with the exception of contact cement, the surface in most cases needs to be roughed up good so the glue has something to grab on to, epoxy is a good one for that kind of gluing.
I have been building with wood for years and have never had a glue joint fail in any of it, it boils down to the type of glue used and the kind of wood glued, our planes are no different.
Leroy
#454
So basically it comes down to whatever the builder is comfortable using. If your planes are shedding parts for no apparent reason, you may want to re think what your doing. How ever, if your like most of us, and still fly planes that were built eons ago, with hundreds if not more flights on them, then carry on. It all boils down to how you like to build be it fast with CA, or taking your time with tite bond. If your joints are tight, your alright. One thing I do agree with is the 5 minute epoxy. I don't use it, but again, just my preference. The best thing we can do is find out through testing and personal experience. I use a mixture af all three. They all have there places.
#455
My Feedback: (11)
Yes good stuff and I love when builders debate there methods, this is how we learn and share. I too am a fast (impatient) builder and use CA a lot, but I am getting better and will gladly glue a part, walk away and resum another day. I do use 5 min epoxy in place of CA for fast settin none structureal detailing. It gives me a little more time to clamp then med or thick CA. I can see some day I will build more with yellow glue just for the slower more relaxed style of building then the instant fast moving CA building.
TB
TB
#456
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Join Date: Mar 2004
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Well said guys! Pretty much what I meant to say!LOL! I agree that the debating process is a good way to find out what everyone else is thinking and doing. That is how I learn too. One thing I meant to mention about five minute epoxy is that it makes a great fuel proofer. I will mix a batch and put equal amounts of rubbing alcohol. Remember, that is twice as much! Mix the epoxy before adding the alcohol then blend with a drill and wire. DON'T PUT THE WIRE IN A DREMEL!!!!!!!!!!!!!!!!!!!!!! Big mess!
I use it after covering is done. Any edges can be coated down. Firewalls, fuel and radio compartments too.
Thanks Tony for the 'impatient' description. It is appropriate for many builders including yours truly. Especially coming from the sixties when glue drying was like watching grass grow! We had twenty four hour epoxy back then! It's like these computers, Once you are use to the speed, anything else is just too sssssllllllloooooowwwww!
Well, Best wishes to all and I hope you got all the 'toys' you wanted. Here is the banding I was talking about earlier. Not sure if here on the build site.
Da bird.
I use it after covering is done. Any edges can be coated down. Firewalls, fuel and radio compartments too.
Thanks Tony for the 'impatient' description. It is appropriate for many builders including yours truly. Especially coming from the sixties when glue drying was like watching grass grow! We had twenty four hour epoxy back then! It's like these computers, Once you are use to the speed, anything else is just too sssssllllllloooooowwwww!
Well, Best wishes to all and I hope you got all the 'toys' you wanted. Here is the banding I was talking about earlier. Not sure if here on the build site.
Da bird.
#457
My Feedback: (6)
Hi guys having read most of your post I would like to add a my comments every glue has its application ware it is best, being an old Gezeer years ago I had an old cabinet maker tell me a story about glues and wood to get good glue penetration into the wood you should always add a bit of what ever solvent the glue base is made from and depending on the evaporation rate of that solvent, and just before it is gone add the glue as it tends to suck the glue into the wood. in his day there was no C/A's but I have found that by adding a tad of water to a joint before adding yellow/white or c/a's (nothing more than a wet brush swipe) gets a better bond and with most all epoxies I have added or used MEK's in the same way, and have never had a glue joint fail, The wood next to the joint has in many cases failed, when looking at the structure after a crash. That said the one exception is A/C grade ply with the smooth finish I generally scuff the surface with 100 grit paper be fore using with any glue.
For me this has worked for the past 65 years.
cheers Bob T
For me this has worked for the past 65 years.
cheers Bob T
#458
Thread Starter
Hi guys having read most of your post I would like to add a my comments every glue has its application ware it is best, being an old Gezeer years ago I had an old cabinet maker tell me a story about glues and wood to get good glue penetration into the wood you should always add a bit of what ever solvent the glue base is made from and depending on the evaporation rate of that solvent, and just before it is gone add the glue as it tends to suck the glue into the wood. in his day there was no C/A's but I have found that by adding a tad of water to a joint before adding yellow/white or c/a's (nothing more than a wet brush swipe) gets a better bond and with most all epoxies I have added or used MEK's in the same way, and have never had a glue joint fail, The wood next to the joint has in many cases failed, when looking at the structure after a crash. That said the one exception is A/C grade ply with the smooth finish I generally scuff the surface with 100 grit paper be fore using with any glue.
For me this has worked for the past 65 years.
cheers Bob T
For me this has worked for the past 65 years.
cheers Bob T
Leroy
#459
Thread Starter
I love Christmas but am always glad it's over. time to work on the plane again, "yeah", piece again!!!
All along it looked like there was plenty of room on the forward decks for all the stuff going in there, well that was before I started putting it up there, the room went fast. With the throttle servo, engine ignition and kill module there was no room for the battery I had hoped to put in there also.I had forgot to add space for the foam pads and had to add another set of slides tried to save as much room as possible for floor details. Fuel tanks shelf was filled up as well with no room to spare. Two 8 oz. tanks are the siphon type, I haven't figured out where to put the fuel fill yet, there is no place to hide it and I'm not doing any hatches that aren't on the real plane, there isn't much room left to work with. Batteries will go under the floor, I can get two of them side by side just ahead of CG, I will have to raise the floor 1/4" to do it, there will be wiring in there also. Next will come the servo mounts that go under the back seat for elevator and rudder, "then" the floor and all it's details, seats should be fun, not to mention all the rest of it, it just takes time
Leroy
All along it looked like there was plenty of room on the forward decks for all the stuff going in there, well that was before I started putting it up there, the room went fast. With the throttle servo, engine ignition and kill module there was no room for the battery I had hoped to put in there also.I had forgot to add space for the foam pads and had to add another set of slides tried to save as much room as possible for floor details. Fuel tanks shelf was filled up as well with no room to spare. Two 8 oz. tanks are the siphon type, I haven't figured out where to put the fuel fill yet, there is no place to hide it and I'm not doing any hatches that aren't on the real plane, there isn't much room left to work with. Batteries will go under the floor, I can get two of them side by side just ahead of CG, I will have to raise the floor 1/4" to do it, there will be wiring in there also. Next will come the servo mounts that go under the back seat for elevator and rudder, "then" the floor and all it's details, seats should be fun, not to mention all the rest of it, it just takes time
Leroy
#460
Bob your old enough to remember the blood powder glue you mixed with water, in the old world fine furniture was glued with it and I used it as a kid, then Elmers came out and that was the end of that. For all I know blood glue may still be being used for laminating ply wood, it has the color of it.
Leroy
Leroy
Hoping everyone had a Merry Christmas and wishing you all a Happy New Year. My best gift was a membership including initiation fee to the club where I am living now [no, not the funny farm (yet)].
sincerely, Richard
#461
To clarify, is that one part of alcohol to one part mixed epoxy (so 50/50 alcohol/epoxy) or one part alcohol to an equal part of each part of the resin (1/3, 1/3, 1/3)?
(sorry for the repeat, forgot to quote the post I had a question about and cant figure out how to delete a post)
(sorry for the repeat, forgot to quote the post I had a question about and cant figure out how to delete a post)
Last edited by pilotbum; 12-27-2014 at 09:24 AM.
#462
Well said guys! Pretty much what I meant to say!LOL! I agree that the debating process is a good way to find out what everyone else is thinking and doing. That is how I learn too. One thing I meant to mention about five minute epoxy is that it makes a great fuel proofer. I will mix a batch and put equal amounts of rubbing alcohol. Remember, that is twice as much! Mix the epoxy before adding the alcohol then blend with a drill and wire. DON'T PUT THE WIRE IN A DREMEL!!!!!!!!!!!!!!!!!!!!!! Big mess!
I use it after covering is done. Any edges can be coated down. Firewalls, fuel and radio compartments too.
Thanks Tony for the 'impatient' description. It is appropriate for many builders including yours truly. Especially coming from the sixties when glue drying was like watching grass grow! We had twenty four hour epoxy back then! It's like these computers, Once you are use to the speed, anything else is just too sssssllllllloooooowwwww!
Well, Best wishes to all and I hope you got all the 'toys' you wanted. Here is the banding I was talking about earlier. Not sure if here on the build site.
Da bird.
I use it after covering is done. Any edges can be coated down. Firewalls, fuel and radio compartments too.
Thanks Tony for the 'impatient' description. It is appropriate for many builders including yours truly. Especially coming from the sixties when glue drying was like watching grass grow! We had twenty four hour epoxy back then! It's like these computers, Once you are use to the speed, anything else is just too sssssllllllloooooowwwww!
Well, Best wishes to all and I hope you got all the 'toys' you wanted. Here is the banding I was talking about earlier. Not sure if here on the build site.
Da bird.
#463
I love Christmas but am always glad it's over. time to work on the plane again, "yeah", piece again!!!
All along it looked like there was plenty of room on the forward decks for all the stuff going in there, well that was before I started putting it up there, the room went fast. With the throttle servo, engine ignition and kill module there was no room for the battery I had hoped to put in there also.I had forgot to add space for the foam pads and had to add another set of slides tried to save as much room as possible for floor details. Fuel tanks shelf was filled up as well with no room to spare. Two 8 oz. tanks are the siphon type, I haven't figured out where to put the fuel fill yet, there is no place to hide it and I'm not doing any hatches that aren't on the real plane, there isn't much room left to work with. Batteries will go under the floor, I can get two of them side by side just ahead of CG, I will have to raise the floor 1/4" to do it, there will be wiring in there also. Next will come the servo mounts that go under the back seat for elevator and rudder, "then" the floor and all it's details, seats should be fun, not to mention all the rest of it, it just takes time
Leroy
All along it looked like there was plenty of room on the forward decks for all the stuff going in there, well that was before I started putting it up there, the room went fast. With the throttle servo, engine ignition and kill module there was no room for the battery I had hoped to put in there also.I had forgot to add space for the foam pads and had to add another set of slides tried to save as much room as possible for floor details. Fuel tanks shelf was filled up as well with no room to spare. Two 8 oz. tanks are the siphon type, I haven't figured out where to put the fuel fill yet, there is no place to hide it and I'm not doing any hatches that aren't on the real plane, there isn't much room left to work with. Batteries will go under the floor, I can get two of them side by side just ahead of CG, I will have to raise the floor 1/4" to do it, there will be wiring in there also. Next will come the servo mounts that go under the back seat for elevator and rudder, "then" the floor and all it's details, seats should be fun, not to mention all the rest of it, it just takes time
Leroy
Can you explain the plumbing of your siphon arrangement on your tanks? How many clunks? Where? Etc...
Randy
#464
Thread Starter
Randy the twin tank design is used a lot on jets which often have 3 tanks and the area you have to work with won't support one larger tank. The first tank, left side, is the primary tank fuel is drawn and filled from, the vent line of it crosses over to the second tank which has a clunk line on it like the first tank and then a vent line. When filling it works the same as a one tank system except the first vent line becomes a pickup line in the second tank, over flow fills the second tank and a vacuum caused in the first tank siphons it back to the first tank. Kinda simple when you think about it but it needs a fuel pumped engine to work like gas engines have.
Leroy
Leroy
#465
My Feedback: (6)
Bob your old enough to remember the blood powder glue you mixed with water, in the old world fine furniture was glued with it and I used it as a kid, then Elmers came out and that was the end of that. For all I know blood glue may still be being used for laminating ply wood, it has the color of it.
Leroy
Leroy
Cheers Bob T
#466
Banned
To clarify, is that one part of alcohol to one part mixed epoxy (so 50/50 alcohol/epoxy) or one part alcohol to an equal part of each part of the resin (1/3, 1/3, 1/3)?
(sorry for the repeat, forgot to quote the post I had a question about and cant figure out how to delete a post)
(sorry for the repeat, forgot to quote the post I had a question about and cant figure out how to delete a post)
You cannot yourself delete a post; it has to be done by people in authority in the forum.
You can edit your post by deleting all the text and the pictures and replace hem by at least three characters like 3 dots or any meaningless 3 characters.
Happy New Year.
Zor
#467
My Feedback: (11)
The side saddle tank setup is a very good setup. Like Leroy mentioned it also fits better then one large tank in most cases. I size my tank so that in a normal (8-10 min) flight I only use the secondary tank. This provides a full tank that the engine draws from. Your clunk will never go dry this way. Then the primary tank that feeds the carb acts as my resurve.
TB
TB
#469
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Join Date: Mar 2004
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Leroy, I used a fuel dot and drilled out the center of the dot and put a fake fuel gage in it and mounted it where the fuel gage and cap goes. Can't seem to find any pictures of mine but use your imagination. It'll look good. Leave enough line to pull it to one side so fuel doesn't get in the plane.
bird.
bird.
#470
Leroy, I used a fuel dot and drilled out the center of the dot and put a fake fuel gage in it and mounted it where the fuel gage and cap goes. Can't seem to find any pictures of mine but use your imagination. It'll look good. Leave enough line to pull it to one side so fuel doesn't get in the plane.
bird.
bird.
#471
Randy the twin tank design is used a lot on jets which often have 3 tanks and the area you have to work with won't support one larger tank. The first tank, left side, is the primary tank fuel is drawn and filled from, the vent line of it crosses over to the second tank which has a clunk line on it like the first tank and then a vent line. When filling it works the same as a one tank system except the first vent line becomes a pickup line in the second tank, over flow fills the second tank and a vacuum caused in the first tank siphons it back to the first tank. Kinda simple when you think about it but it needs a fuel pumped engine to work like gas engines have.
Leroy
Leroy
So, question on this... on dual tank systems like this is it at all common to have a gravity type system say with a second clunk and vent in the first tank and a single clunk and vent in the second tank so as you draw from the first tank, gravity will keep both tanks at the same level? Or even a single clunk and vent in each tank tied together with a T where your draw from so you're drawing from both tanks at the same time (like a full scale Cessna, for example) also keeping both tanks at approximately the same level by gravity? I'm just curious of the various ways of doing this and the benefits.
Randy
#472
My Feedback: (11)
Randy, I first saw the duel tank setup from 3D planes/ pilots. The reasoning was to always have a full tank to draw from no mater what position the plane was in. You never have the chance of a dry clunk. If your just flying scale ptturn then this may not mater to you. Most do it in scale planes for space, you have more options as you can stack the tanks side by side vertically or flat depending on the space you have. I personally do it to have a full tank always, on a normal flight and the second tank is my resurve. Seen to many pilots dead stick (and crash) because they ran out of fuel.
I don't know how it would work having both clunks drawing the same time from both tanks as your vent on the main tank is tied to the clunk on the second tank. The second tank is your vent and overflow. For our modles I think either a single tank with one clunk on a T for filling and de-filling or a side saddle tank set with the main tank with the clunk to the carb on a T for filling, the vent going to the second tanks clunk and then venting out. Either one would be best for a model.
TB
I don't know how it would work having both clunks drawing the same time from both tanks as your vent on the main tank is tied to the clunk on the second tank. The second tank is your vent and overflow. For our modles I think either a single tank with one clunk on a T for filling and de-filling or a side saddle tank set with the main tank with the clunk to the carb on a T for filling, the vent going to the second tanks clunk and then venting out. Either one would be best for a model.
TB
#474
My Feedback: (11)
Progress is moving along.
I got the right wing all setup with servos and linkages. I will install the wing struts so I can put the wings on next.
The fuselage is pretty much done short of some tweaking and detailing.
The door and window is all glued in.
The wing leads are strapped in and ready for the wing.
The matchboxs are strapped in, and I tided up as much as I could.
I will be able to see all the gear for inspections just with the door open, plus I can see the fuel tank too.
With the wheels on it balances neutral I will try and make a CG stand once the wings are on.
TB
I got the right wing all setup with servos and linkages. I will install the wing struts so I can put the wings on next.
The fuselage is pretty much done short of some tweaking and detailing.
The door and window is all glued in.
The wing leads are strapped in and ready for the wing.
The matchboxs are strapped in, and I tided up as much as I could.
I will be able to see all the gear for inspections just with the door open, plus I can see the fuel tank too.
With the wheels on it balances neutral I will try and make a CG stand once the wings are on.
TB