Build an Excavator from Scratch

[pufferfish]

Several times before, in some other projects, I've wished to be able to build my own little louvers.
A previous attempt to make a punch and die works but has imperfections to build a even row of identical louvers.

Today i've started another attempt.
the groove for the die was made with a radius mill and cut off one side.
A sharp cutting edge was added.



The die mounted on a piece of wood together with a stop and a ratched grip



with a quadrant milling cutter i've made the punch.



the punch guide


all together clamped an read for the next louver

you can use a hammer or a press.



the result. I'm happy with it and look forward to make some of them for the hull of the excavator.

[jerry56]

WOW that took a lot of work but excellent results...

[Zabco]

Very nice piece of work there. May just have to copy that. Thanks for sharing.

[frizzen]

That louver punch is wild, they look great!
How do you register alignment between the base and punch holder?

[pufferfish]

I've faced both parts sides together on the mill. Thereby they are absolutely even and a optical alignment was exact enough.

[pufferfish]

A medium issue I've found was the unwanted contact between the superstructure and the undercarriage regardless all the ball-bearings.


So i've added another dedicated flat bearing from igus. called "iglidur"
A .5mm thick plastic, easily cutable with a sciccor.
Glued direct onto the stainless steel with a combination of loctite 770 and 401.



After deburring and polishing the sprocket a first test



Then the optical improvement of the undercarriage begins

The front inner View is now this





And the side view before



and after the improvement

[pufferfish]

Second side panel is done.


the first inner rear cover too


a bit bored by all the cutting and bending I need a bit alternation. so i've milled the teeth for the bucket.

[pufferfish]

Making the working lights. Modern squared style. 15x15x8mm.
each includes 8 smd leds.

.3 mm stainless steel.

[pufferfish]

the stick need some reinforcements.

copying the shapes


apply to 1mm stainless


saw


sawed


after welding these points


turned into this


with this little tool


stick is finally finished and ready to use

[frizzen]

These parts are looking great, and it looks like you'll have a bulletproof model when its done.

[pufferfish]

bulletroof? i hope so

-----

the bucket links are done in a really quick and dirty way. they work but are very wobbly and a good portion of the hydraulic power goes not in the correct direction.



for a proper working they need more guidance.
Therefor i've turned some brass washers 10x15x1mm



and fitting bolts and screws . ( sorry no pic)

every joint is now backlash free and covered with brass bearings.

[pufferfish]

finishing the parts was much more work than expected.
improvements, making more finger friendly, welding all the lines complete and not just some points.
and at least put a brushed surface on it.

[ddmckee54]

I was going to ask how you were cutting your parts, then I saw your saw. You've got some fairly tight curves that you appear to be cutting. What are you using for a blade on that saw?

Don

[pufferfish]

Originally Posted by ddmckee54

I was going to ask how you were cutting your parts, then I saw your saw. You've got some fairly tight curves that you appear to be cutting. What are you using for a blade on that saw?

Don

Hi Don,

the saw is a Proxxon MBS 240/E and the blade a proxxon 28 172 for stainless steel.

The shown curves are the limit for this blade. Narrower curves are possible only with little steps side by side.

[Blender]

This is looking great. The beauty panels pulled it all together so well. The metalwork shows your high standards.

The hard pipes on the boom are a great detail.

[pufferfish]

thank you.

Next thing to improve is the motor mount of the rotary drive.

first attempt. principally working but too weak for the complete weight of the upper construct.




The motor is strong enough, so i need just a better adjustment technic and a more stable mount.

First part is the combined clamping and movement thing

a plan


and the real thing










more to come....

[pufferfish]

the wedge bar is done. cutted from a stainless steel bar.



fits well

[pufferfish]

Still working on the rotary drive.
Today the outer clamps and their flanges to the platform were built.

Befroe that, the old flanges have to remove from the platform. i've used the little 35 mm cuttings discs from proxxon.



The outer clamps get some recesses for the weldable flanges with m4 threads.



After this a first setup of the mechanism happens





works fine but needs some more details before completed....

[pufferfish]

Last part of the rotary drive.

clamp screws with stainless bolts to avoid damaged threads


adjustment with a simple block on the maximum position and an offset of 1/10 mm with a feeler gauge


clamps very well, no more wobble even if i simulate lateral forces like when the bucket is digging

[pufferfish]

The work on the cabin begins.

Some angle-guides...


for this little micro belt sander,...


together with a 90