Loose Robart hinge point (after 3 years)
10-08-2008, 03:40 PM
#28
Senior Member
My Feedback: (1)
RE: Loose Robart hinge point (after 3 years)
I use Gorrilla or equivalent on my hinge repairs. I used to bump rudder ends on the ground when pulling a take off into a hover and was always breaking the bottom two hinges loose in the process. More working time and plenty of expansion. I generally do not bother to wet with water. If the humidity is at 10% or more you already have enough water
Foaming action is reduced but that simply means you have more glue in the repair location than foam. That's a good thing because it holds longer. If required I use toothpicks covered with the adhesive to get the material into the joint. Cover the hinge joint with some Vaseline or similar before you go dripping any type of adhesive around the repair area. You'll be glad you did later.
30 minute works ok for timing purposes. You should get a good 5-8 minutes of working time if you heat the stuff up. Pretty runny in that state.
Foaming action is reduced but that simply means you have more glue in the repair location than foam. That's a good thing because it holds longer. If required I use toothpicks covered with the adhesive to get the material into the joint. Cover the hinge joint with some Vaseline or similar before you go dripping any type of adhesive around the repair area. You'll be glad you did later.30 minute works ok for timing purposes. You should get a good 5-8 minutes of working time if you heat the stuff up. Pretty runny in that state.
10-08-2008, 06:15 PM
#29
RE: Loose Robart hinge point (after 3 years)
Used Pacer hinge glue due to how runny it is. I first tried in a tiny needle and that was a joke. Then I used the elephant needle and it just ran right out of the tip, no flow problems at all. Most of it went inside the aileron and I had to put the wing so it would drip back down into the hinge hole, that kind of sucked. Things never go as planned. But with it braced so it flows back down it is oozing a tiny bit out of the tape so it must be draining back into the hole.
Thanks for all the advice. I didn't want to use the Gorilla due to the mess and foaming. Same with Epoxy. This Pacer stuff cleans up really well and hey, it held a hinge point in a hole that missed the hard wood and held for three years. It's gotta be good.
Thanks for all the advice. I didn't want to use the Gorilla due to the mess and foaming. Same with Epoxy. This Pacer stuff cleans up really well and hey, it held a hinge point in a hole that missed the hard wood and held for three years. It's gotta be good.
10-08-2008, 07:50 PM
#30
Senior Member
My Feedback: (1)
RE: Loose Robart hinge point (after 3 years)
At least you got something in there. Next time you try hinging, try the Gorrilla. To avoid the foaming mess use some low tack tape around the hinge opening. Let the glue expand away. When it sets just cut the tape at the hinge line and pull away. The tape takes the excess foamed adhesive with it, leaving a clean surface. You can do pretty much the same thing with repairs. Just apply some tape tight to the sides of the opening to prevent the glue from foaming out. I'll dig up a couple of pics for the process I have stashed somewhere.
Two pics, one as the glue expanded, the other after pulling the tape. No other clean up performed.
Two pics, one as the glue expanded, the other after pulling the tape. No other clean up performed.
10-08-2008, 08:34 PM
#31
RE: Loose Robart hinge point (after 3 years)
Joe,
Glad to know the repair is done.
The size of the needle depeds on the glue used. I do not know how big the elephant needle is. But in my case (wth 5 min epoxy), the flow is reasonable with the muscle injection needle. The epoxy was not heat and it lands rigt at the pocket.
Glad to know the repair is done.
The size of the needle depeds on the glue used. I do not know how big the elephant needle is. But in my case (wth 5 min epoxy), the flow is reasonable with the muscle injection needle. The epoxy was not heat and it lands rigt at the pocket.
10-09-2008, 07:19 AM
#32
RE: Loose Robart hinge point (after 3 years)
ORIGINAL: Tired Old Man
At least you got something in there. Next time you try hinging, try the Gorrilla. To avoid the foaming mess use some low tack tape around the hinge opening. Let the glue expand away. When it sets just cut the tape at the hinge line and pull away. The tape takes the excess foamed adhesive with it, leaving a clean surface. You can do pretty much the same thing with repairs. Just apply some tape tight to the sides of the opening to prevent the glue from foaming out. I'll dig up a couple of pics for the process I have stashed somewhere.
Two pics, one as the glue expanded, the other after pulling the tape. No other clean up performed.
At least you got something in there. Next time you try hinging, try the Gorrilla. To avoid the foaming mess use some low tack tape around the hinge opening. Let the glue expand away. When it sets just cut the tape at the hinge line and pull away. The tape takes the excess foamed adhesive with it, leaving a clean surface. You can do pretty much the same thing with repairs. Just apply some tape tight to the sides of the opening to prevent the glue from foaming out. I'll dig up a couple of pics for the process I have stashed somewhere.
Two pics, one as the glue expanded, the other after pulling the tape. No other clean up performed.
How did you get the hinge knuckle so clean? Put oil or vaseline on it before hand?
10-09-2008, 07:39 AM
#33
RE: Loose Robart hinge point (after 3 years)
ORIGINAL: nonstoprc
Joe,
Glad to know the repair is done.
The size of the needle depeds on the glue used. I do not know how big the elephant needle is. But in my case (wth 5 min epoxy), the flow is reasonable with the muscle injection needle. The epoxy was not heat and it lands rigt at the pocket.
Joe,
Glad to know the repair is done.
The size of the needle depeds on the glue used. I do not know how big the elephant needle is. But in my case (wth 5 min epoxy), the flow is reasonable with the muscle injection needle. The epoxy was not heat and it lands rigt at the pocket.
You should have seen me with that tiny needle trying to get the Pacer hinge glue through it. I tried the heat gun and everything. One tiny drop came out and it was plugged up solid. [:@] Then onto plan B.
10-09-2008, 11:27 PM
#34
RE: Loose Robart hinge point (after 3 years)
The Pacer stuff did not do the trick. Too much gap to fill I guess. The hinge moved in the hole.
So I did Gorilla, hope it works this time. So how long does it need to dry before I fly? Let's put it this way, I glued it at 10:00 tonight and will be in the air by about 10:00 am tomorrow. It said 80% strength in 1-2 hours and 100% in 24 hours.
Supposed to be an awesome day.
Joe
So I did Gorilla, hope it works this time. So how long does it need to dry before I fly? Let's put it this way, I glued it at 10:00 tonight and will be in the air by about 10:00 am tomorrow. It said 80% strength in 1-2 hours and 100% in 24 hours.
Supposed to be an awesome day.
Joe
10-10-2008, 12:03 AM
#36
My Feedback: (2)
RE: Loose Robart hinge point (after 3 years)
I was gonna suggest a needle the last time I saw this thread. Im a nurse and have access to 18 gauge needles that seem to work ok for applying epoxy down into holes. I suck it up with a 3ml syringe then slap the needle on.
10-10-2008, 09:30 AM
#37
RE: Loose Robart hinge point (after 3 years)
Yep it's GTG today for sure. TOM (Pat), thanks for the picture convincing me Gorialla glue is clean with the masking tape. It's really strong. I drilled 6 holes. One in front and back of the knuckle, two on either side of it, on top and bottom of surface. It's got a lot of glue this time. I dampened it plenty to let it expand like crazy. I bet it will hold. I'll report back after a gallon of fuel today. 
PS: The 18 gauge needle didn't work (my gf's a doc, brought me a bunch of assorted sizes). The Gorilla glue didn't want to flow. Only with heat would it work a little. The elephant needle from the hardware store is my fav.
PS: The 18 gauge needle didn't work (my gf's a doc, brought me a bunch of assorted sizes). The Gorilla glue didn't want to flow. Only with heat would it work a little. The elephant needle from the hardware store is my fav.
10-10-2008, 10:50 PM
#40
My Feedback: (2)
Join Date: Jan 2008
Location: saint louis, MO
Posts: 465
Likes: 0
Received 0 Likes
on
0 Posts
RE: Loose Robart hinge point (after 3 years)
If you choose to repace all the hinges, I've found that cutting the nuckle and removing the surface, then use a soldering iron to melt out the old hinge leavse a perfect hole. Then use a 3/16 drill bit to clean up the hole and re-hinge.
Dude that is a DAMN good idea, i am going to use it next time b/c those robarts are a biatch.
Dude that is a DAMN good idea, i am going to use it next time b/c those robarts are a biatch.
10-10-2008, 11:11 PM
#41
Senior Member
My Feedback: (1)
RE: Loose Robart hinge point (after 3 years)
The hinge knuckle always comes out that clean when you cover it up with Vaseline. Takes a little time with a toothpick to make sure all the hinge finger gaps and pin ends are packed and covered but it pays off big time when everything is dry.
All I do is lightly slice the tape at the hinge bevel line and lift each piece up. About 95% of the time the end result is what you see in the pics. The other 5% might leave a little dab of foam on the outer sides of the hinge. A quick pick with an Exacto blade lifts those away.
For a repair that requires material injected into a hole, mask off like in the picture and cap off the injection hole with a little tape to keep any from backing out as it expands.
All I do is lightly slice the tape at the hinge bevel line and lift each piece up. About 95% of the time the end result is what you see in the pics. The other 5% might leave a little dab of foam on the outer sides of the hinge. A quick pick with an Exacto blade lifts those away.
For a repair that requires material injected into a hole, mask off like in the picture and cap off the injection hole with a little tape to keep any from backing out as it expands.
