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Hello all,
I'm building my .60 GP 300 extra and was going to install robart hinges but then realized that I needed blocking for the lenght of the pins. Oh well, I'll use the dubros that I have anyway. The dubros are 1/2" long from the pin, the trailing edge of my wing, elevator, and rudder are 1/2" thick. The problem I'm having is that at a number of locations there happens to be either a cross brace or solid wood which I had to apply glue during the build up. When slotting out the hole for the hinge I am stopped by the CA glue that had wicked into the trailing edge and cut my slotting depth down to about 7/16th, so I'm not able to fully recess the hinge. I have already cut all the slots so I really don't want to relocate them. My initial thoughts were to cut the 1/16th off the hinge and possibly drill one or two more hole in the hinge for gripping power for the epoxy ( due to when I cut the 1/16th off it will probalbly just cut into the existing holes on the end of the hinge ). I could do that and also pin it. Is there a way of cutting through the hardened wood to get that extra 1/16th. I personnaly don't want to use pins, for cosmetic reasons, and never had a dought about the strenght of the epoxy holding onto the hinge. On my old trainer I had the dubro hinge and expoxied it in and I couldn't pull it out. I would appreciate any confirmation of my suggestions, and would appreciated other tips. Thank you all for your input and expertise. Regards, Pat

MinnFlyer

My Feedback: (4)

Get a good grip on that knife and cut through the hardwood and/or glue. But BE CAREFUL that you avoid cutting any SKIN, specifically YOUR SKIN!

powertoys

My Feedback: (2)

PDF,

Find a friend with the Great Planes motorized slot maker. That thing will go like a hot knife through any kind of butter. I personally have one and have used it to cut through CA soaked balsa and areas with epoxy. The epoxy takes a little time but it is 50 times faster than a #11 xacto blade. Good luck.

Mike

Blow n Go

What you need is a dremel with a fresh cut-off blade. It makes the slot slightly wider than the hinge, but that works out perfect and will cut through whatever you have! Trim the hinge with scissors so you only have one row of holes..........cut right along the first set of holes as a guide. This makes sure the hinge will not bottom in the slot and throw off alignment. When you install the hinges, run a piano wire through the hinges and do them all at one time...........this allows the hinges to self align. Do all the hinges to the control surface first, then add the second halves of the hinges and glue them all to the airframe at once.

Finally, use 5 minute epoxy. It fills the slot and will NEVER let go of the hinge. Wipe the area clean with alcohol just before you push all the hinges in at once. Position the surface (or plane) so gravity keeps the epoxy in the slot until it starts to get tacky. Remove the pin once the epoxy is tacky.........don't wait for it to totally cure hard.........and don't try it while still gooey. Carefully clean the extra epoxy from around the hinges with the tip of an exacto, and pull the pin.

This technique ensures perfect alignment and takes very little time.

CJ

BigSkyRCFlyer

My Feedback: (36)

Ditto on the Great Planes motorized hinge cutter, Awesome. Dremel with cut-off wheel works good too, or the old fashioned xacto does the trick. As Minnflyer said "PLEASE" be careful with a blade and trying to force or cut something tough/hard........OUCH. Good Luck.

powertoys

My Feedback: (2)

Yes the Dremel will work but be careful! I've used that technique before on other projects and when that wheel bites into some thing hard like cured epoxy unexpectedly it can jump into the nearby area like soft balsa or covering (ouch!). Those wheels will shatter without any warning if they get in a bind, so be very careful and wear eye protection. With all that said, Dremel is my friend when building.

Mike