Due to the current situation with lack of N95 masks in the stores I resorted to 3D print a pair for me and my wife.

I also made the designs freely available on thingiverse: https://www.thingiverse.com/thing:4264883

Here is the description of the project:

High airflow Respirator mask in 3 sizes: Large, Medium and Small.

Large works for a large male face. 125mm height*
Medium for a smaller male face. 115 mm
Small works for a female or a 10 y/o kid face. 105mm height.

*I measure face height from chin to the centre of the nose bridge.)

Designed to take 1 or 2 55mm cotton pads into each of 3 filter housings.
Install filter medium into the bottom of the cap and screw on to the mask body.

Make sure to print 3 caps for each mask as well. Caps are the same for all mask sizes.

Used white window insulation sticky cord on the inside to add cushion and improve insulation.

Had to also use a file and fine sanding paper to make sure the mating surfaces on the mask body are smooth and do not have any air gaps.

Disclaimer: I designed and printed this for me and my family. It has not been tested, and although I designed with safety in mind, I do not claim it can prevent any infections or viruses. Use at your own risk. PLEASE be careful when testing: different cotton pad brands have different density and 2 pads per filter may cause difficulty breathing! Please make sure to remove the filters and sanitize the mask and caps after each use.

The models are designed in Fusion 360.

Parts printed on Creality Ender 3S Printer with the following settings:

• Layer Thicknss: 0.2mm
• Infill: 20%
• Filament Material: PLA
• First Layer Speed: 35mm/s
• Wall Speed: 75mm/s
• Support: everywhere
• Support Speed 75mm/s
• Support Density: 1 line at 5%

1 mask plus 3 caps takes about 14 hours to print at: 75mm/s.

Please wash your hands and stay safe.

We will get through this!

Cap Size:0.55 MB Large Mask Size:3.29 MB Medium Mask Size:3.79 MB Small Mask Size:3.78 MB

Hello everybody!

I have not made many blog posts here lately because i have been working a lot on new features and simply did not have much time for anything.
So I decided i'd make a little report on how we are doing and where the project is.

First things first.

I just released an update to HSMAdvisor v1.503

• Drilling tools now consider Shank Diameter when calculating maximum allowed torque on the tool.
  This will lead to more safety when using, say 1" tool with a 0.5" shank.
• Thread Milling tools have been immensely improved.
  Shank diameter is now included into the calculations.
  Default Length is now 2.5 diameters
  Improved suggested cutting speeds and feeds

Our Multiple Language Translation Program is chugging along nicely

Several people messaged me about intentions to build translations so far.

At this point we have people working on translations for the following languages:

• Croatian
• Serbian
• Portuguese
• Perhaps Polish (I see someone uploading translations, but the person have not contacted me about it)

Mobile FSWizard app is due for major improvements

Major visual re-design is under way and we are working on making FSWizard Mobile accessible on more devices in more ways.
It is going to be a fully fledged WEB app, that can be run on any internet-connected device. Even on a desktop.

Integration with HSMAdvisor Machine Profiles and Tool Libraries is also planned.

Perhaps we are going to drop native support for Google Play and iOS stores. I am sick of them charging us 30% for their services.

Canned cycles are used every time we need to drill, ream or tap holes on our CNC machine

Standard Fanuc G-Code language supports more than a dozen canned cycles.

The most common cycles that will cover 99.9% of your g-Code CNC programming work are:

Subsequent holes

You can drill additional holes After your canned cycle has been initiated.
Any line with X Y position will be treated as another hole position.

Each position can have its own Retract value, feed rate and retract height modifier.

G80 - Canned Cycle Cancel Code

After all the holes of the canned cycle have been drilled, it is required to call G80 code in order to cancel the current cycle.

At my day job I am starting to do more and more manual programming.

Which i do not realy like, but since am at it anyway i have decided to keep piling little articles about G-Code programming into this new category.
This way when i forget things again i will be able to quicly refresh my memory.

Program Start

O0001 (COMMENT OR PROGRAM NAME)

Starting safety blocks

(G20 IMPERIAL UNITS, G21-METRIC)
(G17 XY ARC PLANE, G18-XZ, G19-YZ)
(G40 CANCEL TOOL RADIUS COMPENSATION)
(G49 CANCEL TOOL LENGTH OFFSET)
(G80 CANCEL CANNED CyCLE)
(G90 ABSOLUTE POSITIONING MODE)

G20 G17 G40 G49 G80 G90

Tool Change Routine

(T14 - call 2.5" Face mill)
(M6 - Perform tool change)
(G0 - rapid feedrate)
(G55-G59 - Choose Work Offset)
(X, Y - Command a Position to move to)
(S - choose spindle speed)
(M03 - Turn spindle on Clockwise, M04 - Counter-clock wise)

T14 M6
G0 G54 G90 X{X} Y{Y} S{SPEED} M03;

Apply Tool length offset at retract height, Turn on Coolant

(G43 H14 Z2.0 - All codes must be in the same line Apply cutter length offset from record #14 to cuttent tool, move to 2.0 above work at the same time )
(M8 - Turn on Coolant)

G0 G43 H14 Z2.0 M8

Rapid tool to plunge height

G0 Z{Z_PLUNGE}

Plunge to cutting depth at plunge feedrate

G01 Z{Z_DEPTH} F{F_PLUNGE}

Make a straight cut in xy direction at cutting feedrate

G1 X{X_POS} Y{Y_POS} F{F_FEED}

Retract to plunge height at either rapid or retract feedrate

G1 Z{Z_PLUNGE}

Retract to rapid height, turn off colant

(M09 - Turn OFF coolant)

G0 Z{Z_RETRACT} M09

Retract to tool change height, turn off spindle

(G28 G91 Z0 - all coes must be in the same line, move Z axis to HOME POSITION through a reference point)
(G91 Z0 - Causes reference point to be the current location, thus sending axis straight up )
(M05 - Turn off spindle)

G0 G28 G91 Z0 M05

Perform Next tool change or end program

M30(end program)

.....and this is why they are so heavy.

I have stumbled upon this video the other day.

It shows a very good reason to keep those doors closed at all times when runing your machine.

HSM or High Speed Machining is becoming more and more popular each day.
Many of us have seen those youtube videos where endmlls remove large amounts of material at high speeds/feeds.

While definitions of HSM may vary between tool manufacturers and even individual shops, the physics behind it remain the same.

In this article i would like to explore flat endmills.

HSM is not about ramping up your speed/feed overrides to 200% and puling out your smartphone to record another youtube-worth video.

What is HSM?

HSM is a complex of programming, machining and tooling techniques aimed at radical increase of productivity.

Programming

The cornerstone of HSM is low radial and high axial engagement of an endmill with the workpiece.

There are many CAD/CAM systems that allow you to create HSM tool-paths. Mastercam's Dynamic milling and SurfCAM's Truemill are some of them.

When radial cutter engagement with the material is smaller than the radius of the tool an interesting thing happens.
Chip load- the distance the tool advances per cutter revolution per tooth- does not equal the actual chip thickness anymore.
Chip thinning mainly happens at radial engagements below 30% of the diameter.

In order to get compensated chipload you need to multiply recommended by manufacturer chipload by the chip thinning factor.

Usual Radial Engagement for HSM toolpaths however is between 5 and 15%.

Axial depth of cut varies depending on geometry, but

Radial Chip Thinning HSMAdvisor Screenshot