[msimpson99]

The KRMx01 was designed and built for the sole purpose of writing my first CNC how-to book. It took me six months to design and build and another six months to write the book.





Just as I had finished the book, a friend of mine offered me several booths at the DC Science and Engineering Fair to demo the machine. I told him that it was not designed to be easily transported. He then replied, “Design another, that is.”

Six months later the KRMx02 CNC was born. I had no idea that the success of the KRMx02 book would soon orphan the KRMx01 book.

Most of my time is now spent working on and supporting the KRMx02 book. I didn’t want the work that I put into the KRMx01 to go to waste so I decided to offer the book as a free download.

The KRMx01 download page is located here:

KRMx01 Digital Download

You can download the complete KRMx01 book, BOM and configuration files.

In order to keep the book download to under 5MB, the resolution on the illustrations and layout drawings have been reduced. There are a couple that are a bit hard to read. I will post higher resolution images of those requested in this forum on a as needed basis.

Please note that the download is a interactive PDF with some links and is not printable. If you want a printed version of the book it is available at a reduced price on Amazon here:

[ame=http://www.amazon.com/gp/product/1938687108/ref=as_li_tf_tl?ie=UTF8&camp=1789&creative=9325&cr eativeASIN=1938687108&linkCode=as2&tag=kronosrobot ic-20]Amazon.com: Building the KRMx01 CNC: The Illustrated Guide to Building a High Precision CNC (9781938687105): Mr Michael Simpson: Books[/ame]

You can get more information on the KRMx01 CNC here:
Building the KRMx01 CNC

[WJHildreth]

Michael,

Just wanted to resume the conversation that we started with the contact form on your website about the KRMx01 Machine.

I will answer questions on the following forum. They have setup a section
for the KRMx01 there.
Kronos Robotics - CNCzone.com-The Largest Machinist Community on the net!


1) The upgrades for the KRMx01 are still valid and are currently in a second
book that will be released sometime in early 2013. IE its finished. It
just needs to be setup with my printer/distributer.

2) I don't know what you mean by defunct. There is a second book, and I
plan on a third as well for the KRMx01. Most of the work and projects have
been done. It's just a matter of publishing them. Please note that the
second two books will not be released as PDF. They will be printed only.


Please ask your remaining questions on the forums above.

I have downloaded and read your book. Very well done I might add! I ask about the KRMx01 being defunct or dead because I seen you were rather active on the KRMx02 version of the machine. I was thought maybe that you were no longer going to develop on the x01 model.

I have no issue with buying the books direct from you or Amazon, I just didn't want to buy something that, was being replaced by a different or better product.

So I guess the only question that remains for me to make the plunge so to speak, is would I be better off going with the x02 model?

My current machine, a homebuilt JGRO, has been ok, but I see the problems build over time from a machine that was built from wood. Still, it has been a great learning experience and some great way for a dad to spend some time with the teenage sons. Anyway, I see the need to move to a steel and aluminum machine.

Is the second machine just rack and pinion or can it be built with leadscrews as well? What are the advantages of rack and pinion? My current machine uses 450 oz/in motors. Will these be big enough to use on either the x01 or x02 models? I currently use LinuxCNC to control my machine and would like to stick with it. Do you know of anyone that has built your machine and run it with LinuxCNC?

Thanks for your patience with me. Thanks for the book!

Regards,

Joe
:wave:

[msimpson99]

The add-on upgrades to the KRMx01 are complete.

E-Chain (Dragon Cable)
Homing Switches
360 Controller
Probe
AirExchanger
EStop
SmoothStepper
Router Control

Most of the upgrades are not listed on the Kronos Robotics website because they will all be released in subsequent books. The first of which will be released at the beginning of 2013.

Since the major upgrades for the KRMx01 are complete, I personally, will do no further enhancements to the KRMx01 design. That’s not to say you can’t do enhancements. I know of at least one individual that replaced the aluminum angle rail with a hardened V Rail.

[msimpson99]

Q:
Is the second machine just rack and pinion or can it be built with leadscrews as well?

A:
The KRMx02 is R&P only



Q:
What are the advantages of rack and pinion?

A:
There are both advantages and disadvantages to both systems.
In general Lead screws will yield more precision and less speed. On larger machines lead screws tend to whip unless the speed is dropped. R&P don’t have any length limits, and tend to be faster.



Q:
My current machine uses 450 oz/in motors. Will these be big enough to use on either the x01 or x02 models?

A:
In both my KRMx01 and KRMx02 books I use the 4 axis electrics kit from CNCRouterParts (4 Steppers, G540 Controller, Power supply).
I have tested and run the CNCRouterParts electronics on all my machine builds and they are as close to plug and play as you can get. You can use other electrics but they are not covered in my books.



Q:
I currently use LinuxCNC to control my machine and would like to stick with it. Do you know of anyone that has built your machine and run it with LinuxCNC?

A:
Both books cover the installation, setup and configuration, and operation of Mach 3 control software on a Windows PC.

[msimpson99]

The KRMx01 and KRMx02 are very different machines.

The KRMx02 was built for production work. Many of the KRMx02 builders own businesses. I use my KRMx02 machines every single day.

The KRMx01 is not suitable for heavy production work because of the Derlin ACME nuts. Under heavy loads they wear. This is true of any CNC that uses Derlin ACME. Because of the wear, I use two nuts on each ACME screw and this helps. The X and Y and Z axis on the KRMx01 ride on aluminum rails. I show you how to condition these in the KRMx01 book. This helps reduce the wear, but does not eliminate it. Some have replaced the aluminum rails with hardened V rails.

The KRMx02 machine has more aluminum and steel than the KRMx01. It also will cost you more to build.

That said, if you are coming from a Wood or MDF build the KRMx01 will be a major upgrade for you.

[msimpson99]

The KRMx02 is an easier build than the KRMx01.
80/20 has created parts bundles for both, but the KRMx01 requires more fabrication.

On the KRMx02 If you purchase the parts bundles you need only drill holes and assemble to complete the KRMx02.

The KRMx02 is more modular than the KRMx01 and will support more upgrades. I am currently working on a 3D printer upgrade for the KRMx02.

[msimpson99]

Just to show my commitment I have accelerated the release of Book 2 in the KRMx01 series.

This book takes up where the first leaves off.


It should be available in the various online book stores in the next two to three weeks. Once it goes live I will start a separate thread to support the contents of the book.

Covered in the book:
Clamp Table
Fences
Basic Operation of the KRMx01
Dragon Cable (Echain)
Homing Switches
EStop
Gantry Brace

[WJHildreth]

Michael,

Thanks for all the replys. With that I would like to add that I am still trying to decide between the KRMx01 and KRMx02 models. I will most likely buy the KRMx02 book, so I can comapre the builds in a more direct manner, then decide which I went or need to pursue.

I originally built my machine to cut wood patterns for sand casting, them went to plaques and 3D puzzles. It is starting to get more use and if all works out will have an outlet to sell some stuff made with it. I don't know what you mean by production but if the KRMx01 is not suited for it, then perhaps I should lean closer to the KRMx02. Does production mean runing 24/7, 8 hours a day, 4 hours a day ...

Also,

I have invested in motors and electronics and would like to use them. The wiring part does not bother me, nor does setting up LinuxCNC to control the machine. Would you be open to USER addendums for these type of changes?

Regards,

Joe

P.S. Look for a book order next week.

[msimpson99]

If you decide to use different electrics that's fine. The configuration on both the KRMx01 and KRMX02 will most likely remain the same.

Its just the hookup that will be different. Both machines use NEMA 23 motors, On the KRMx01 you cant change from a NEMA 23 to something else unless you make changes to the motor mounts. On the KRMx02 machine the base design uses the CNCRouterParts NEMA 23 R&P design. You can use the NEMA 34 R&P drives on the KRMx02 as well.

To support the KRMx02 I have some private forums. (At least for now they are private). You are free to do a build log on my forums or the CNC Zone. However if it deviates from one of the base build designs, I will move it to the advanced section.

[msimpson99]

Let me define my view of a production machine.

First, I define production as a using a CNC machine on a daily bases every day. The machine runs continuously for more than a couple hours a day.

A production machine, would be a machine that could keep up with that work and not need tweaking and adjustments more than every couple months.

Any CNC that uses Derlin ACME nuts on the X and Y axis that is used in a production environment is going to require tweaking to compensate for wear on the bearings. In addition the KRMx01 uses aluminum rails and you were thinking of using it in a production environment, the rails should be upgraded to hardened steel.

The KRMx02 uses steel rails and steel R&P track on the X and Y axis. Yes these will wear over time but the R&P drives are spring loaded to keep tension on the racks so you don’t have to tweak once setup. The KRMx02 uses the same X axis as the CNCRouterParts machines.
All that said, there are exceptions. My KRMx01 machine was given to my daughter and son-in-law and is used in a semi production environment for their business. It still has the stock aluminum rails, and they are quite happy with its operation.

[WJHildreth]

Michael,

Thanks for the info. As it stands, The KRMx01 will probably fit my needs nicely. I am only cutting puzzles and plaques and signs now. However, demand is rising and I need something better than what I have. But, because I don't want to make a hasty decision, I am going to mull it over the noodle for a few days keeping in mind the information you have passed along to me. I will still probably buy your KRMx02 book anyway just so I can look at the build comparisons.

Again, thanks for being so patient with me about this. I jumped head first in my JGRO build. It was a wonderful learning experience, but I want to think it through a little more this time around.

Warm Regards,

Joe Hildreth

[msimpson99]

Smart move.

[WJHildreth]

I ordered your KRMx02 book last night. I am looking forward to reading it. After I compare the two machines, I will decide then which to build. Thanks for your help and support Michael.

Joe

[msimpson99]

The KRMx01 Book 2 is now available on Amazon.

[ame="http://www.amazon.com/gp/product/1938687116/ref=as_li_tf_tl?ie=UTF8&camp=1789&creative=9325&cr eativeASIN=1938687116&linkCode=as2&tag=kronosrobot ic-20"]KRMx01 Book 2[/ame]

This book takeup where Book 1 leaves off.

[WJHildreth]

Michael,

I have ordered both KRMx01 books this morning. I figure it is the best way to support you regardless of which machine I decide to build.

Now I have a question about book 2 of the KRMx01 machine. Does it come with a cd of DXF files or other electronic information to cut the cable or other upgrade components?

Thanks,

Joe

[msimpson99]

It does not come with disk, but has private links for what you need.

[WJHildreth]

Thank you sir.

I have been thinking about the KRMx01 and x02 and have pretty much decided on the x01. Most of my CNC cutting is for patterns for sand casting, where I leave a certain amount for shrinkage and machining. Tolerance is more important for me than speed and I don't intend on doing cutting as a business, other than I have folks who like to buy plaques and 3D puzzles.

Since you developed the x01, if I were to make .250 deep cuts in lauan with a 2 spiral upcut .125 inch endmill, could I run it at 50+ inches a minute on that machine?

I bought your x02 book as well and will read it before I make my final decision, but thought I would get your valued input.

Thanks,

Joe

[msimpson99]

The KRMx01 cuts pretty good at 50IPM. However, I would not cut .25 deep with a 1/8" bit. You stand a good chance at breaking the bit. Better to make two passes.

[WJHildreth]

Michael,

Again thanks for the info. I know that 50IPM at .250 deep on an .125 endmill is pretty stressful on the bit. I have cut at 25IPM in 4.75 lauan at a 1/4" and never broke a bit. I have friends that cut at 80IPM like that and have only broke a few. I don't think I am willing to push that hard, and if the machine can run at 80" plus, then I am already faster than my current 25IPM even at 2 passes, so it is win - win. Again, I am more concerned about keeping some sort of tolerence on a pattern to be cast than speed.

I have all three of your books ordered. 2 are on their way, so hopefully here in a couple of weeks I will start building one or the other.

I just want to make one more statement. I understand the amount of time it takes to design and test, redesign and test and document. I appreciate the work you have put into these projects and giving me the opportunity to be lazy!!! HAHAHA I don't think most people realize the amount of time and energy that goes into producing something. Most people are instant potatoes and miss the benefits of the crock pot.

Thanks for sharing your work with the rest of the community! I appreciate what you have done. :-)

Joe

[msimpson99]

While lauan is a pretty soft material. You probably can cut it in a single pass. The only thing I would say here:

It sounds like you like to push things to their limmit. There is nothing wrong with that. Keeping that in mind you should lean toward the KRMx02.

When I desinged the KRMx01, I had no idea I would be designing another. Hence there is not much of an upgrade path from the KRMx01 to the KRMX02 machine. The Electrics kit, Router, K2CNC mount is about all they share.

Something you might want to look into, since you have all the books, is to build the KRMx02 Z axis and attach it to the KRMx01.

This is something I wanted to do, but never got around to it. The KRMx02 Z axis is the same that is used on the CNCRouterParts machine, with a few upgrades.