Improving the K40 Optics: Mirror #2 Replacement

K40 Mirror Mount and Adjustment Redesign: Part 2

DRAFT

This the 2cnd part is a continuation of my effort to redesign and improve the K40 optical path. 

Part 1 is here .....

In this post I will outline the design and assembly of a new mount for mirror #2. The same part design philosophy used in the first post was employed for mirror #2.

There are 4 posts that pertain to improving optical components and alignment:
Improving mirror #1
Improving mirror #2
K40 optical alignment tool theory & design
Using K40 alignment tools

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Please consider donating (button to the right of this post).

Your donations help fund additional research, tools and parts that I will return to the community as information.

For other information on the K40-S build use the  K40-S BUILD INDEX with schematics

Parts

• Adjustable Lens Mount [Ebay]. This part seems to keep changing. If this link goes dead try searching for: "20MM/ 0.79'' REFLECTION MIRROR FIXTURE MOUNT FOR Co2 LASER MACHINE 1 PC Redsail"
• 1/4" Acrylic [lowes]
• 6- 4x.7mm flat head screws [Lowes]
• 1- 4x.7mm pan head screw

Design

Similar to mirror #1's design this design consists of three parts: the base plate, sub-plate and rotary sub-plate.

Note in the pictures below my experimental alignment jig is installed. The peice of acrylic screwed to the gantry in the foreground is not part of the mirror mount. Neither is the cardboard flag and clamp to the right.

Installation

The #2 mirror assembly is assembled like the #1 mirror assy:

• The rotating sub-plate is screwed to the bottom of the black mirror mount
• That sub-assembly is then screwed to the sub-plate using one screw from the bottom
• That sub-assembly is then screwed to the base-plate using two screws in the provided horizontal slots.
• The entire assembly is then screwed to the gantry using the vertical slots shown just to the left of the belt and pulley

Note: I will add pictures of the part drawings to make this more clear.

Adjustments

The mirror has three coarse adjustments as viewed from the front of the machine:

• Left-right using the two screws and slots to the left of the pulley.
• Forward-back adjustments using the screws to the left and right of the rotating sub-plate.
• Angular adjustments using the rotating sub-plate

Fine adjustments are made using the 3 brass screws on the black frame once the coarse adjustments are locked down.

Summary

A view of the cabinet showing the new optical assemblies in the homing position.

Next

I will install new mirrors and complete a full optical path alignment and report the results here.

Enjoy and comment,

Don