Build an Excavator from Scratch

[skeeter]

AWESOME project!
This thing should be a beast of a machine once completed!

[pufferfish]

Originally Posted by Jared

Very nice pipe work. What is your method for bending without kinking them?

Thank you. I've choosen the easy way. 6x1mm stainless pipes are not easy to bend but with the right tools it's possible and up from 15mm radius without any kink. I'm using a "RIDGID 600 series lever bender" for 16mm radius.
with the enclosed examples you are quickly enabled to make reproducable multi-angle bendings.

Originally Posted by frizzen

Looks like a lot of progress! Shaping up into a very impressive machine

Was the totaled truck something like an Airport Fire engine, or a Trial Truck? Atleast the ejector seat worked.

It was called "s.o.f.t. superfast offroad fire truck" and should be a quick response bush fire truck.

"ejector seat"

Originally Posted by skeeter

AWESOME project!
This thing should be a beast of a machine once completed!

indeed.
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After a short vacation I've save up enough point on my patience account to begin with the last two hydraulic cylinders. Patience is needed because me and turning internal threads are not friends.
fortunately, this time it works at the first attempt and some other parts are build too.
Pistons and guide rings from brass, rod and cylinder from stainless and the cylinderhead is from aluminium. (nothing to weld on the head and very easy to turn)


The head is the most complicated part. Internal thread and a recess for the guide ring on the inner side. thereby the guide ring is oil lubricated.



On the outside are three grooves for o-ring sealings.


Threads will be sealed with loctite 542.

[pufferfish]

Todays work: The completion of the stick cylinder.

After applying the orings i've prefilled the cylinder with oil



The thread was filled with loctite



after 4 hours the glue isn't 100% but for a first little test tight enough
but before, i've made a hose-guard from 5x0,3 stainless for the hose to the front



the last cylinder for the bucket is prefilled too and can't wait to mount him





The cylinder and stick in action you can see in this little clip (self hosted)

https://blog.rb-fotos.de/wp-content/...es-stick-1.m4v
(moving from the nineth second on)

[trucker n]

man very nice and smooth