these dots
 

these dots look like spotwelds there are a few more around the joint.

https://cimg5.ibsrv.net/gimg/www.rcu...917d437284.jpg

Those are not spotwelds, as there is nothing to weld there, also not on the inside. They are probably clamping marks from the welding jig used to hold the two halves in position when welding the two halves together.

is this joint a weak point?
 

It appears only to have welds on the side and not the inside and outside of the joint.
And does it limit the amount of heat this cap can handle if i choose to solder?

I have never seen one of these welded caps fail. The older units (pre 2014 IIRC) were soldered, I had several, they kept well but could snap in a crash. The ones I soldered myself, held less well. One of them came loose under normal use.
I tend to replace the ignition if the cap gets damaged.

inserts are done - Always a challenge to make little pieces all the same :) had to make a couple for setup. O
https://cimg1.ibsrv.net/gimg/www.rcu...5266f9039b.jpg
nce I got rolling I could make one in 10 min.. 3 on the way Lonnie...

Parts for the printer arrived. Just need to revise the filament spool bracket and I can start printing abs and asa.


https://cimg2.ibsrv.net/gimg/www.rcu...497949c80b.jpg

Looking good Dave!! how do you like the Bed leveler? I have one but haven't got around to installing it yet.

Yes that is the new 1/4-32 plug cap design with the circle clip-loc... those come already spot welded together, just insert the hi-tension lead end into the resistor, and then attach the shield braid... you could use the spot welder to attach the braid, but the silver solder allows easier removal of the braid, if or when you need to replace the plug cap.

The ones Bert is referring too are the earlier twist-loc type... those you have to completely assemble the inner insulator, and resistor and then solder the two sections together... the solder would fail if you didn't get a good soldered joint... those twist-loc plug caps are still available from CH ignitions, but they come fully assembled now and induction welded together, all you have to do is just insert the hi-tension lead end and attach the shield braid.

I prefer the the twist-loc type myself, but the RCxel 1/4-32 spark plugs have very soft hex base to them, and wear with engine vibration ( mostly 2 strokes )... rounds off the edges and the twist-loc won't hold, that's why they came up with that circle clip-loc idea.... not too impressed with that idea either... I don't know what would be a good solution, none of the 1/4-32 plug caps are any good... CH has the higher quality twist-loc caps, and that's what I've been using along with the Rimfire VR2 / VR2L spark plugs.

Most definitely prefer the twist lock types too. Their only (slight) downside is that the cap cannot be turned on the plug to get the HT lead in the "perfect" position, but that is only a minor inconvenience.

The bed leveling is interesting. The sensor ensures the perfect z spacing for the first layer, helping adhesion. What it doesn't do: actually level the bed, especially if your gantry isn't square, so the process for me is: level the x using measurement blocks (in case the 2 z axis steppers are misaligned), tram the bed to ensure the bed is level, and then apply the bed mesh to ensure the perfect first layer

Here's where it's useful, once the sensor z offset is determined, you no longer have to use a feeler gage (sheet of paper) to zero out z. The sensor does the measuring and the deviation is displayed on the screen during tramming. It's pretty slick.
​​​​​
the machine stores a mesh of the build plate that it generated using the probe and then when you print, you issue a couple g codes and it now probes the bed in 3 or 4 spots and tilts the bed mesh to match the probed points before printing.

You should install yours and flash the new Merlin firmware.

:):):):):):):):)!!

I'm still waiting on that return address Chris. If you don't send it I'll be emotionally damaged.:D

You mean moreso than you already are? 😀😀😀

And another tested engine..
 

This .40 la was on the now black plane when i got it.
Yesterday took it apart, cleaned it and changed all crappy screws with proper socket head.
The carb mounting screws are m3.5 no idea why they choose a relative obscure size..
Found some of the screws bought almost 30 years ago to replace damaged screws on my .40 sf.
The only original screws are the air bleed and the self tapping remore needle mounts.

So today mounted on the test stand.
Just for fun used just a hand pump, chicken stick and nicd glow igniter.
The engine fired on the first flip but did not keep running.
Flipping again it kept running backwards like a way to rich engine does.
So slowly leaning and it started the right direction.
Another engine that starts by hand, runs and idles reliable, power.. not so much.
It will go on a controll line model under restoration so power is not a requirement but handstarting is verry usefull.
https://cimg3.ibsrv.net/gimg/www.rcu...35365ddfd3.jpg
os .40 la

plugin
 

Have you tried the "Bed Level Visualizer" ? It helps showing how level your plate is.

The visualization is also built right into the printer firmware too. Still not quite started using octoprint. And I'm not sure I really need it with the new Marlin firmware.

only if in another room
 

Octoprint is most usfull to do things remote when the printer is in another room.
If your printer is near your computer then its less usefull.

this does not look right
 

Don't think this plane is designed for .40 engines.
Mounting does not line up at all.
Lets see if other engines fit better.
https://cimg5.ibsrv.net/gimg/www.rcu...2aeea3b922.jpg
big plane, to small engine?

That is one of the drawbacks, and probably another reason for introducing that circle clip-loc version... possibly a hi-breed version of two... a twist-loc at the plug end, and then the center barrel section allowed to turn a few degrees either way to adjust to the angle of the hi tension plug lead... only issue there is coming up with a reliable means of rotating at the barrel that won't wear with vibration, and remains firm to hold in its position.... I can't think of anything that would not eventually wear to the point that it becomes loose and then causes electrical noise... and it needs to be compact... maybe a sprung loaded center section with a fairly stiff spring, that can turn 15 degrees or so in either direction.

about spark plug caps
 

The impression i get from looking at mine is that they are just a tube for shielding/ground and a resistor that contacts the center of th spark plug.
There are 2 plastic spacers and a spring. That is all i see.

Should not be too complicated to copy with a lathe or tube bending tools.
What if the plug side is make like a "gland" used with junction boxes.

like one of these

https://cimg1.ibsrv.net/gimg/www.rcu...c111f9706e.jpg

Make a metal version that mounts upside down (compaired to thte picture) and tighten the nut to secure.
If really paranoid about vibrations include a setscrew to lock the nut in place.
The other side could be tube bend with a radius so it can be one piece.

Likely way to expensive to mass produce but as a home made unit it might outlast all others

That would work... a compression collet type fitting, or just two flanges pinched together, that you tighten after positioning the plug lead... it could be made of metal much less bulky than your plastic example.

Full scale aircraft engines use something similar,

https://ibb.co/tKhT90x

Double post,

In "real" aviation, I have no idea how it is nowadays, but in the past, sparkplugs would have threads, and the HV leads would have some sort of screw on plug, a bit like that gland. At least, I have seen that on the big radials. EDIT, I see John allready posted that, and better than me, with a linky... :D

The spark plug itself is involved in the connection between the hi tension lead and the spark plug body...

Just found out that your rights to manage your uploaded images are take away, So I'm looking for a different image host, as the one I'm using to control access, RCU stores a copy of those images

Here an cut away image
https://ibb.co/tKhT90x

Whose rights? Mine?

RCG stores uploaded images as well. Not uncommon.