Nose and nose gear - part 6

Nose gear leg (6.6 hrs)

The nose gear leg (NG-1L) is a fiberglass piece I bought from FeatherLite last year together with the main gear bow.

Main and nose gear legs

While the main gear needed a lot of BID reinforcement to add torsional rigidity, the nose leg only takes 2 layers of BID for... as the manual calls it... “split protection”.

Plan's directions

First as always, I knocked the slippery shine off the nose leg with the sander, being careful not to remove too much material.

Sanding, the EZ way.

To quickly remove the corner sharp edges, I secured (in a very unsafe manner) my router to the big table, and ran the leg past the router bit as if it were a router table.

Routing the corners

I still had a bit of manual sanding to do, but it was easily done with my perma-grit tools. Speaking of which, I’m finding myself using the flat one more than any other of them, followed by the round tube sanding tool.

These sanding tools are awesome!

Glassing was the usual sequence of cutting the glass, wetting the piece with pure epoxy, applying the glass and epoxy, and peel-plying where needed.

BID selection

Pure epoxy sponge bath

BID pre-preg application

Peel-ply added

After cure, I removed the peel-ply, flipped the part over, and Bondoed it to a couple of screws, exactly as I did when glassing the main gear, to make a sturdier setup, then repeated the glassing procedure.

Front of the leg about to get fiberglassed

Sleeping beauty curing overnight

The Saran-Wrap helped hold down the edges, and prevented air from being sucked into the layup from above.

Another overnight cure, a little trimming, and voilà... a ready to use nose gear leg.

Quick way to get rid of the sharp edges

NG-1L done

The biggest source of concern at this point was to make sure the 4 holes attaching the leg to the NG-6A casting were drilled so that the far end of the leg would be centered between both NG-30s. I used shims and a caliper to arrive at equal gaps on either sides of the leg.

Finding the center position

Desired position captured by the clamp

NG-6A and NG-5. The top of the nose gear leg needs to go in there.

With NG-6A clamped into the desired position onto NG-1L, I transferred both of them to my drill press. Since the nose gear is bowed, I used parallels to make sure that the casting’s reference machined surfaces were parallel to the table before drilling. 

Parallels (one on each side) ensure the casting is horizontal

For the actual drilling operation, I switched to a more rigid way of holding on to the work.

Nothing should move now

Holes were drilled as far as possible (half way), then finished by hand on the bench.

The holes drilled in the leg matched the ones on the casting (NG-6A) as well as the ones on the top plate I made on the mill (NG-5), and everything fit as I expected, until I tried to bolt it all down.

This just isn't going to work!

Another day in the life of a non-kit builder 

The other side is good

As if I needed another reminder that I was not building one of those exquisite Van’s RV kits, a fair amount of custom grinding with a Dremel wheel proved necessary to make sure all washers laid down flat enough to bolt it all together.

All better now!

CNC mill conversion - part 16

xbox 360 controller

Today’s addition to the CNC mill conversion project belongs both in the “cool things to have”, and the “absolutely not necessary” categories.

Walking around the shop carrying a wireless keyboard had gotten a little old, so I knew I wanted a dedicated remote controller for the mini-mill. I was prepared to spend around $100 on one, but then I saw a guy on YouTube who used an xbox controller on his CNC router table.

A quick check on eBay for genuine Microsoft xbox controller (important detail) revealed that one could be had for around $25, so I decided to give it a try.

The file and instructions on how to hook it up and run it can be found here (toward the bottom of the page). 

running the mill with an xbox controller

The wireless version of the controller is supposed to work with Mach3 as well, but I hear that most other non-Microsoft controllers run into compatibility issue (read: random nasty mill crashes), so be careful what you get into.

Nose and nose gear - part 5

Making NG-8 (and NG-5) the hard way (27.9 hrs)

With the mill mostly completed, the time has come to enlist its services in the production of the first few airplane parts, and since I’ve still got a lot of learning left to do, I tried stacking the odds in my favor by selecting two easy part to make, at least in theory.

NG-8 and NG-5 are mostly a 2D cutting job. There are a few holes, profiles, and some chamfering to top them off. 

What could go wrong?

I’ll concentrate here on NG-8, since NG-5 benefitted of all the lessons I learned in producing the former.

What I was trying to achieve

But first, the two flat panel (NG-30) that make up the nose structure needed to be drilled and sanded together to ensure they’d line up later on. That's what the NG-8s will attach to.

Matched drilling the 2 nose frames

Cleaning up NG-30s while mated

Getting back to the story... NG-8’s are aluminum round plates (2 needed) that flank the nose gear hinge mechanism (NG-6A), and bolt on the NG-30s.

NG-8 plans' description

NG-6A nose leg hinge casting

Left and right nose frame structures (NG-30)

I cut two aluminum blanks on the band saw, and went to work.

NG-8s in the making

The way things really went!

The engraving was a bit of an overkill since it won’t be visible from the outside, but what the hell, I think they look cool anyway.

Long EZ jewelry

It's hard to photograph something that shiny

Obviously, I could have knocked both NG-8s out in about an hour, had I done it by hand, instead of the 2 weeks I spent working on them. But that’s not the point. I learned a lot from making them, and NG-5 took just 2 hours, and produced no scrap pieces. Still a bit long, but exponentially shorter.

The lesson on fixtures was also not lost on me, and that’s the first thing I made (on the back side of the NG-8 one) when I made NG-5.

NG-5 fixture

Perfect countersinking on NG-5

Test fitting NG-5 to NG-6A

Next, I mounted the NG-8s on the nose frame.

Marking the hole locations

Drilling the 4 NG-8 holes

Screw inserted to prevent NG-8 rotation

Outer NG-30 pivot point hardware

Same thing on the inside

NG-8s might never be seen again

I still had the holes on the actuator brackets to transfer onto NG-30s, so I started drilling on right one.

Transferring the bracket holes to the nose frame

Later, I mated it with the left one and went through all holes once again with the drill press.

NG-30s bolted together for further drilling. Motor depressions on the top are now evident.

Same thing, different angle.

Drilling the top bracket holes through to the bottom NG-30

Last to get drilled were the clearance holes at the very top (1”, 2.5 cm), for the actuator hinge bolts. 

The biggest drill bit I own

All the holes are now drilled. The dark areas mark 34 layers of BID, and one of Kevlar.

All there was left to do was to bolt them all together, and see how they all fit.

Nose structure completed

Left view of the nose structure

The depressions in the foam to clear the motor gearbox worked out perfectly

She looks ready to go!