Tips on drilling out for Robart hinges
 

Hello all,
I'm test fitting some robart hinges before I decide to use them on the next plane. I used some scrap wood and drilled the 1/8" hole for the pin and when I install them they won't go in al the way. I'm trying to set the center of the pin parrell with the edge. The barb section is 1/8" put when it starts to taper to the pin hinge section is flares out to a larger diameter and prevents me to getting in deeper. I used a countersink tool also but it doesn't taper enough. Any tips that you use that would help in this install.
Thanks,
Pat

RE: Tips on drilling out for Robart hinges
 

Robart makes a little jig that helps you drill your hinges in the center of whatever you are workin on then for the root part of the hinge where it is bigger you can make a little tool out of aluminum that sort of looks like a hinge with a bigger section wher the hinge is bigger and file it to shape...It takes a while but it lasts a long time and you poke it in the hinge hole and wiggle it around till you are satisfied that the hinge is fitting okay and you move on to the next hole...Thats what I have done for yrs and I have never had a hinge failure yet..One more thing I use ordinary yellow carpenters glue to stick them in...I just wipe the excess glue from the hinge and let it dry over nite...The next morning you go to move it and it is stuck solid...You give it a good twist and it goes " crack " and the glue breaks away from the plastic hinge and the hinge is as free as a bird....Even though the glue dosent really stick to plastic it has incased the hinge in a tough material that you would need a hammer to break.I sticks to the balsa and you will never pull it out ...Try just one hinge in a piece of balsa and you will see what I mean...

RE: Tips on drilling out for Robart hinges
 

Hey, PDF... if you have or have access to a Dremel too, they have a bit that's tapered from a point. I've even used this bit in a regular drill to eopn up the hole to accept the thicker part of the hinge by the pin.

RE: Tips on drilling out for Robart hinges
 

I use a cone shaped deburring tool in reverse to open the hole enough to fit the knuckle. Once you find the right one you will be good to go for a life time. Wet the hole with a Q-tip and use pacer hinge glue or something similar. I like it better then epoxy, plus epoxy does not stick to the plastic . Take some tool oil or melted Vaseline and put a drop on the hinge point and it will not be effected by the glue. Also take a drop of oil on your finger and rub the covering on either side of the hole. If you do find the pin sticking a drop of acetone will free it up easy enough. Don't be afraid to use an extra pin or two in each surface. They move so freely your servo will never notice them. :D

RE: Tips on drilling out for Robart hinges
 

After I make the holes, I just take an exacto knife and square off the sides of the holes. The hinge is square toward the center anyway. It does not need to be perfect as the hinge will push the balsa in a little during the test fit. I have also started using Gorilla glue instead of epoxy. When done right it is stronger and easier.

David

RE: Tips on drilling out for Robart hinges
 

I have a small set of needle nose pliers. After I drill the main hole I insert the meddle nose pliers and rotate them in the hole and this makes a perfect countersunk hole of compressed balsa. Works for me and never had one fail or pull out. Also I use gorilla glue to glue them in. Just rub a little oil on the coating around the hole, not in the hole of course, and the foam from the glue will just easily break off after curing.

RE: Tips on drilling out for Robart hinges
 

I used the drilling jig that you can buy. I put petroleum jelly around the pin to stop the epoxy getting into the pivot. Works well.

RE: Tips on drilling out for Robart hinges
 

http://www.rcuniverse.com/magazine/a...article_id=269

OOPS Sorry, this is not a good reference for DRILLING, just gluing http://www.rcuniverse.com/forum/js/f.../sad_smile.gif

I use the Robart drilling jig and have for years. Haven't found anything better but I'm open to something new if it works better!