Some early pictures of using the CNC

I mentioned yesterday that I was going to make a mouse pad of the Escher Reptile. I started on making a model in SketchUp. I then exported it into a STL file (much like I would do for 3D printing. I loaded that into PyCAM, where I was able to define the bit size from the CNC machine and have it generate the g-code.

Once that was complete I loaded it into the driving software that came with my CNC machine and ran it through some test runs to make sure I wouldn’t break the bit… Here is a view of a test run. That little yellow thing moving around represents the bit cutting the wood. Based on the size and type of the bit, many layers may be required to cut through the wood.

Once the test was done I found a scrape piece of walnut veneer I had lying around and had the machine go at it. You can see the Reptile on the left that I’ve already cut out. This GIF shows me cutting out another one.

I know I have quite a bit to learn, but I was happy with my progress so far. I’ll not be able to get back to this for about a week but plan to post about various attempts.


Finally broke down and purchased a small CNC machine

This little CNC device came out of China and seems to operate well. I did have to design and 3D print the clamps to make it easier to use.

The device itself is about 18″ x 12″ and has a vertical range of about 2 1/2″. It comes with some fairly simple software that is open source and seems easy to use. I am just getting started creating the toolpath (G-code).

The assembly manual was usable, but I did beef it up a bit as I went along. I forgot to say that it came in well over 100 pieces. It took me about 4 hours to assemble, and that was only because I made two mistakes along the way. The lack of those details were some of the areas I’d enhance the manual. I’ll have a few more posts about my learning in the coming weeks as I learn to do more and actually create some things. One of the first things I’ll create is an Escher Reptile mouse pad out of walnut, maple and cherry boards.

It also came with a laser head that I’ll need to play with at some point as well.

E-mail not as productive as we’ve been told

Some of us have thought this for a while. The ability to passively offload a task or just type off a thought to remove it from our plate is a technique that has been honed for decades.

There is a recent article in The New Yorker titled Was E-mail a Mistake? that covers some research into this question. If you’ve ever wondered how your life was consumed by ‘communications’, it is worth a read.

I’ve had e-mail in one form or another since the 1970s. For a while back at the turn of this century I would received 300-400 work emails a day, EVERY DAY of the week. Each of these being hand crafted and critical to the individual who sent it. My role was global in nature, so I am not sure how it would have worked any other way, but I do remember many a Saturday being spent catching up on all the ‘communications’ for the week. I didn’t have the admin support that some of the leaders of that organization had to sort the wheat from the chaff.

It does make me wonder what the folks who wrote this article think about the proliferation of personal life, asynchronous communications techniques (e.g., twitter and blogging). The article was focused more on business decision making in an office environment. Based on the amount of time I see folks with their nose focused on their phone, that might be a minority of time spent in modern life.

At the end of the article it states:

The era that will mystify our grandkids is ours—a period when, caught up in the promise of asynchronicity, we frantically checked our in-boxes every few minutes, exhausted by the deluge of complex and ambiguous messages, while applauding ourselves for eliminating the need to speak face to face.

Based on the current use of technology today by digital natives, I doubt that our use of asynchronous communications is what will mystify them.

Talk about having some bad luck with hard drives

About two weeks ago, my user drive began to run slow (I have an SSD for my system files and all my user files on a separate spinning hard drive). Later that day, it just failed — the OS couldn’t see it. When I took it out and put it in a USB enclosure, it just made some clicking sounds and couldn’t be seen from Windows Disk Manager. The drive was probably 8-10 years old, so it was about time. I have all my personal files backed up three different ways, two on the cloud (Google and OneDrive) and one with a physical drive using File History

I thought, “oh well at least I have a spare drive sitting around, this wont take long”. It was a 3TB drive that I was just using for storing media backups. This drive had not been used very much at all, but was quite a few years old. I piled it on the sacrificial pyre of system storage and installed it in my desktop, formatted it and then loaded on my backup files. This process probably took 4 hours and I had everything back working again.

This new drive ran great for about two weeks and then it also started to make a clicking sound. When I rebooted, the drive diagnostics stated “Hard drive failure imminent”. Foolishly, I thought “This is a new drive, it must be some kind of strange issue that can be fixed by a hard reset”. I powered down the machine and everything seemed to be working fine, until I ran the same program where I first heard the clicking sound and then down she came like a tower of bricks.

This time the computer could at least see that there was a hard drive, it just didn’t like the partition definition… So I pulled out my trusty copy of Spinrite and put it to work. No success, the BIOS and DOS could see the drive, but didn’t want to examine it (I hope the new version of Spinrite gets released soon so it will use a more modern approach to accessing the drives. This enhancement has been talked about for years).

Anyway, I went to Amazon and looked for a highly-rated but relatively inexpensive 3TB option. There are many of them out there. I chalked up the previous experience as practice and hoped that I’ll be up more quickly this time, once it arrives later today. Fortunately, I have a tablet running windows and OneDrive syncing my files so I can still function.

The lessons from all this is:

  1. Keep multiple backups – drives fail
  2. If you ever see a “Hard drive failure imminent” take it seriously

There is another lesson to keep in mind that has more to do with security and that is to have your user accounts run without privileges. Have a separate admin account where you do all the “system stuff”.

A box using the 45-degree lock miter bit

Lately, I’ve been doing a great deal more woodworking. I came across this very interesting bit that you can use to make 90° angles in boxes. It is called a 45° lock miter bit. You use a router to cut the joint into the boards to make a very tight connection.

Domino box

Unfortunately, the router that I normally use isn’t precise (or maybe strong) enough to do the joint reliably. The bit keeps shifting, so the joint is not as clean as it should be.

I thought I’d share the instructions here anyway though, since relatively few folks know how to use this bit. The design creates a box that is just large enough to hold a double 12 set of dominoes.

Box explosion

Tools used:

Table saw 3/8” router bit Planer
Router table Drill press Chop saw
¾” lock miter bit ½” drill bit Band saw
½” router bit Set-up blocks Digital height gauge
1/8” round over bit Various router featherboards  
Lock miter bit
  1. To start off, prepare a finished board that is 6 ½ -7” wide ¾” thick and 40 inches long at the start of class.
  2. Using the chop saw cut from the finished board, a 12” board (the front and back) and one 13” board (the two sides). Note: Originally, I cut the boards into their final length before using the lock miter bit but found that anything less than about 5 inches long was very difficult to add the lock miter cut and likely dangerous. This plan doesn’t cut the side boards until after the lock miter joints are in place.
  3. Trim the 12” board width to 5 5/8” on the table saw and the 13” board width to 6”. Note: Keep the scrap wood, since we will use these during the router setup.
  4. There are several ways to set up the lock miter bit on the router table. If your board is EXACTLY ¾”, you can use the setup guide (white plastic) that came with the bit. I prefer to use the digital height gauge to measure and adjust the height of the bit to the same as the board thickness. Set the height of the bit to ¾”. Note: Lock the router height when you have adjusted the height appropriately.
  5. Set the guide up against the bit and adjust the fence horizontally until it just touches the guide. Once you have the fence set, you can lock down all the fence knobs. Note: You can lock down the main adjustment knobs and use the micro adjustment to move the fence in or out. Once you have the fence in place, lock down all the knobs.
  6. If your board is not exactly ¾ of an inch, it still needs to be less than ¾ of in inch validate the setting of the depth of the bit by aligning the board horizontally and ensuring a straight edge laid along the board would almost touch the cutting edge of the bit. To orient the board vertically and do the same with a straight edge, checking that it almost touches the front cutting edge of the bit.
  7. Make a test cut on a board or boards that are the same thickness (hopefully the scrap boards from earlier). Note: This is a very aggressive bit, so be sure to use feather boards to hold the board up against the bit when you run it through.
  8. Test to make sure they fit together appropriately. If you have it set up right, make sure the bit height is locked in place. If the boards don’t line up, go back to step 5 and make sure the bit hasn’t moved during the testing process. Note: If you do the alignment check on a single board, you will need to cut it in two and then connect the boards together. When the bit is setup properly, the edges of the two boards should be flush.
  9. Run the longer dimension of the 13” board (these will be the two side pieces once cut) through the lock miter bit in the router while laying the board horizontally on the router. Be sure to do both sides of the board and that the cuts are aligned in the same direction. Note: Be sure to use a feather board to help keep the board up against the router. Holding the board consistently against the deck and the fence is important.
  10. Run the longer dimension of the 12” board (the two end pieces once cut) through the router oriented vertically. Be sure to do both sides of the board. Note: Use the tall featherboard and ensure as you press down and run the board through that your hands hang over the fence, in case the board shifts unexpectedly. Be careful not to press down too hard, since your routing to a fine edge. If your board is bowed make sure you place the bow away from the bit (on the outside).
  11. Using the chop saw cut the 12” board into two 5 5/8” pieces. Cut the 11” board into one of 4 7/8” and one of 5 5/8”. You can now check the box to ensure that it fits together. Mark the left, right, front, back boards, as well as their top and bottom. Note: If you suffer any tear out, you may be able to address it when you trim the boards. Cut so the lock miter joint is facing up. Use a sacrificial board if the board you’re cutting doesn’t touch both sides of the fence.
  12. From the remaining large board, cut a 5 5/8” board, using the chop saw. This will be the bottom of the box.
  13. Using the band saw cut the bottom board width to 6”.
  14. Now we need to cut the grooves into the sides, so the top can slide into it. Install the 3/8” router bit and adjust it vertically until it will cut 3/8” into the board. Lock the height once you have the correct setting. Note: When pulling out any bit from the router DO NOT raise the router all the way, since this can warp the deck or damage the router.
  15. Adjust the fence so it will cut into the side boards, 3/8” from the top of the board. Note: A more accurate and repeatable approach would be to use the 3/8” set-up blocks located in the tool room (on the right-hand side as you enter the door – see the attached photo). Place the set-up block between the bit and the fence and adjust accordingly.
  16. Now we shift our attention to the side boards, using a 3/8” router bit, cut the groves into the sides and the larger end piece, 3/8” down from the top and 3/8” into the board.  The top board will slide into this groove when the box is assembled. Note: You should be able to lay the board flat on the router for greater control when making the cut.
  17. Now install the ½” router bit and adjust the router height to cut 3/8” into the board, similar to what was done in step 17.  Lock the router height once you have it set. Adjust the router fence so that the bit will cut 3/8” into the edge of the board. Lock down the fence. Note: We moved to the ½” router bit, so the bit extends beyond the edge of the board. We wouldn’t want any slivers of uncut wood if our adjustment is further than 3/8”.
  18. Cut a 3/8” deep rabbet around the entire bottom of the box, so it can fit inside the box sides when assembled. Note: After you make your first cut, be sure to check the width of the rabbet. It is OK to be a tiny bit wider than 3/8” but you cannot be less than 3/8”, since then the box will not fit together.
  19. Use the same settings to cut a groove (rabbet) along the bottom of all 4 sides, on the inside of the box. Now the bottom should fit within the assembled box.
  20. Run the remainder of the original board through the planer until it is 5/16” thick. This will give us a sixteenth inch clearance to slide. Note: The board should be of sufficient length to meet the length limit listed on the planer storyboard.
  21. Measure the size of the opening at the top of the box. We’d like it to fit fairly tightly within the sliding rails at the top of the box and extend out to the edges of the box.
  22. Measure the top board so it has a T shape to cover the front joints of the box.
  23. From this thin board, cut it down to the measurements identified, using the chop saw and the band saw.
  24. Optionally, you can use the drill press to make a ½” diameter hole ¾” from the edge of the board at the center of the top board.
  25. Use the band saw to trim off the unused lock miter on the sides boards above where the top slides in.
  26. Fit, sand and glue the box together. Note: Once glued, this joint is not coming apart. In fact, sometimes I have trouble getting it apart even when it is not glued.
  27. Optionally, install a 1/8” round-over bit into the router and shape the edges of the assembled box, on the sides and the top.
The finished box

Had to get a new printer

Last week the HP 7610 printer that has supported me faithfully for nearly a decade died (RIP). It came up with a missing or failed printhead error?!??! I researched this error six ways from Sunday and after dismantling and reassembling the printer, I finally threw in the towel.

HP 7740

Now it was time to find a replacement. Since I tend to make quite a few designs for woodworking…  so I was looking for a large format (11×17) multi-function device. I also wanted a separate ink cartridge for each color, since I hate the waste of the multi-color cartridges. I ended up ordering the HP 7740 and it showed up in 48 hours! It was easy to set up and only took about 10-15 minutes, to get my first print out.

This printer is a pretty large device and holds quite a bit of paper in two trays (of two different sizes of paper if I want). So far, I’ve been very happy. It prints faster than my old printer. The only downside I’ve come across so far is that it doesn’t have a duplexer. I don’t really do that much two-sided printing, so it’s not that much of a loss.

I was able to purchase the printer during the Memorial Day sale, so it didn’t cost much more than buying a set of print cartridges. I still have my HP employee discount, since I retired from there, so that was an added bonus.

Probably the biggest issue for switching printers was “What am I going to do with my backup inventory of ink cartridges?” Naturally, I turned to E-bay. There is still a little over a day left and the four cartridges I am selling as a bundle are bid up to the price of getting one of them new. Usually all the action is in the last hour, so hopefully I can recoup at least half that investment back. continues to surprise me with their outstanding service

A few years ago, I purchased a doorbell from and installed it on my house in Texas. When I moved to South Carolina, I uninstalled it and mounted the doorbell button in my new home.

I had some issues with the doorbell connection, but Ring support walked me through how to get greater current to the doorbell (the builder had used some very thin twisted pair Ethernet cable, so I just used some of the extra unused wires in parallel to cut down on the resistance).

Yesterday, when I looked at the door bell, I noticed the soft button that people push had split vertically, in two places. I figure it was a few too many Amazon purchases (since they typically ring, drop and dash). I thought “That’s not good, I wonder how to get a replacement button.”

About 6:30AM (Eastern) this morning, I went to their site to see how to order a replacement. I started an on-line chat with Junmar. Like all on-line chats, they followed a script and asked a number of questions that they should have already known the answers to but the support person seemed genuinely interested in the problem. I sent him the relevant, detailed information and a photo of the problem.

Within minutes, he said that Ring realized I was outside my warranty period (probably by well over a year) but “We can replace the device.” Needless to say — I was shocked. I then went through the process of validating all the shipping information…  

Every interaction I’ve had with Ring has always exceeded my expectations. Good job!