What's new
Van's Air Force

Don't miss anything! Register now for full access to the definitive RV support community.

Drilling a new tail knuckle to and existing stinger

mike newall

Well Known Member
Sponsor
As it says - we have a pre drilled stinger and an un drilled tailwheel knuckle.

Any good ideas as to how to drill it to match the existing holes :cool:
 
I can imagine a drill guide fixture that you would make. It clamps to the stinger, and has a drill guide that you drill first through the stinger holes and into the guide with no knuckle installed. Then slip the knuckle on, align it straight, and back-drill through the guide.

Might take a few hours to make.

Also, I really really recommend using taper pins instead of bolts through the knuckle. ACS has the reamer and pins, and nice washers that fit the radius of the knuckle and provide a flat surface for the nut. Using taper pins also makes the drill alignment a little less critical, since you will then ream the taper which will enlarge the holes in the stinger slightly. I put one pin in from the left and one from the right to keep more edge clearance between them.
 
I can imagine a drill guide fixture that you would make. It clamps to the stinger, and has a drill guide that you drill first through the stinger holes and into the guide with no knuckle installed. Then slip the knuckle on, align it straight, and back-drill through the guide.

Great minds and all that rot...
.
 

Attachments

  • Tailwheel Jig1.JPG
    Tailwheel Jig1.JPG
    65.5 KB · Views: 305
Blake has that info, and more, on his website.

He probably even hijacked Dan's photo of the drilling jig! It is the best photo and worth a thousand words for sure.
 
Blake has that info, and more, on his website.

He probably even hijacked Dan's photo of the drilling jig! It is the best photo and worth a thousand words for sure.

The best? Oh gee, I dunno...I have a hard drive full of them ;)
.
 

Attachments

  • Tailwheel Jig2.JPG
    Tailwheel Jig2.JPG
    54.1 KB · Views: 203
Showed the fixture to my mate who has time on his hands and a full engineering shop with a 6 station CNC machine....

He said, I will have one to you tomorrow, but it won't be like that.

My word, it arrived this morning, I figured it out and it worked superbly. In the photos you will see it clamps on at one end with 3 grub screws, the sleeve centralises the stinger, two vertical grub screws centralise where you will cross drill. Left the knuckle in for the first hole. locked it, cross drilled the first hole, inserted a bolt then cross drilled the second hole, then inserted the knuckle and secured it. Back drilled the other way, pinning with a bolt after the first hole. Disassembled, de burred and reassembled - Ssssshhhhhhhhhhlup went the bolts as they were a friction fit !





C5D14A28-0C18-42A9-B1EF-9820C5DE8EDF-L.jpg



E2AE4263-03FC-4398-92F6-FB513AB8A053-L.jpg



IMG_9999_heic-L.jpg
 
Last edited:
Here is what we came up with a couple of years ago. The drill jig was machined from billet and is partially split with two threaded holes with bolts (on opposite side) to squeeze down, clamping it to the tailwheel spring. We used it for the socket on the right with cross-drilled fasteners (original builder config). If the fasteners had been like the ones on the other sockets (conventional config) the horizontal drill hole in the jig would have been vertical instead of horizontal. We also installed taper pins in lieu of the original bolts as an upgrade:

eagPi4a.jpg
 
Last edited:
Back
Top