My goal today was to get the crankcase vent tube forward angled segment —which cracked off while I was bending it— welded to the remainder of the tube, and then hopefully move on to getting the dipstick rod joined to the dipstick cap.

But first, I kicked off the morning with some cowling repair by adding some carbon fiber plies to some low/concave spots and divots.  In these small areas I would rather add smaller patches of carbon fiber and sand it down even, then to have thicker applications of micro which tends to crack over time on the ever-vibrating thin-walled cowlings.  So using a small amount of mixed up epoxy and a few selectively cut carbon fiber scraps, I made my repairs (I’ll note that I used the ProSet epoxy which I recently heated up to bring back to liquid vs big glob form).

I then left my cowling repair layups to cure as I did a bit of research on welding 6061 aluminum.

Once back out in the shop, I trimmed down the cracked edges at the break in the crankcase vent tube and got to work on welding that back together.  I first did a good amount of TIG runs on some scrap 6061 and felt I had decently warmed up for this welding session.  However, I have to say that I’m bit flummoxed with the sheer ugliness that ensued.  I’m not a great welder, but I’ve held my own in a number of welding projects in the past: stick, MIG and TIG, so I’m not trying to blame my equipment… it could certainly be me.  But I just don’t seem to be striking good arcs, getting good puddle action or decent melting in of my welding rod.  I’m guessing I may need to do a total swap-out and deep cleaning of my electrodes, consumables, etc. because strange things are afoot at the Circle K.

I really didn’t want to keep attempting a bad position, so I stepped away from welding for a bit and concentrated on another required engine task: the dipstick.

Here we have the older, shorter stock Lycoming oil level tube and dipstick, as well as a 3/16″ diameter 6061 rod and an eBay special properly-threaded and o-ringed cap for the taller gold-anodized Superior oil level tube.  BTW, I found out about this aluminum cap from an RV bubba on the VAF forum.

It was time to join rod and cap to create a proper dipstick.

I started by taping up the knurled edge of the oil dipstick cap and mounting it into my lathe’s chuck.  I then set up a center drill (pic 1) and fired up the late to get me a nice center drill starter hole for my drill bit (pic 2).

I then drilled a 0.75″ deep hole into the underside of the oil dipstick cap…

which allowed me tap 10-32 threads into the hole (pic 1).  I then tested out my tapped hole with an AC grade bolt (pic 2).  All looking good this far.

I removed the oil dipstick cap from the lathe chuck and replaced it with the now cut-to-length 3/16″ oil dipstick rod, and then proceeded to create 10-32 threads on the top end of the rod with a manual die.

Here we have the cut-to-length 3/16″ diameter oil dipstick rod with 10-32 threads at the top end.

I left the dipstick rod chucked up in the lathe as I then secured the oil dipstick cap in the milling machine’s vise, with protective tape on each side as to not scratch the finish!

I then drilled a hole into the side of the cap down into the center of the cap to allow me to tap 8-32 threads into the hole….

which I did next.  This threaded hole will secure an 8-32 setscrew, which in turn will secure the 10-32 dipstick rod threaded into the dipstick cap.

With all my holes and rods threaded, I then gooped up the dipstick rod’s threads with Steve Beert’s magic Toyota hi-temp RTV before threading the dipstick cap onto it.

Last year I had to buy some 8-32 thread-locking cup-point setscrews for my AeroLED Nav/Strobe light assemblies (one would have thought they would be included in the light kit, but I digress…) and have quite a few left over, so I grabbed one to use here (pic 1) and started threading ‘er in (pic 2).

And Voila!  Here we have a new, functional dipstick rod and cap unit.  I put it next to the old one for contrast.

I then installed it into the Superior oil level tube (pic 1) and tightened ‘er up (pic 2).  Appears to work a treat.

Now, I clearly still need to create the oil level marks on the dipstick for it be of any real use, but I’ll do that when the plane is in more of a half grazing position as the bird would be during preflight.

I’ll do some more pondering on my crankcase vent tube issue, but it’s very late and I’m packing it in for the night.  Pressing forward!