Network Update for Nov

While fretting about the ever increasing connectivity bill, I discovered that I could get faster internet for about $8 more per month from Telus, my current provider.

We don’t have fiber in our area, so all I can get is an upgrade from 25mb/s to 75mb/s download speed. Still, for $8 that’s a no-brainer. I called and an installation was arranged.

In order to get this speed, the modem needs a bonded pair of wires, so a second jack was added and the new modem connected.

Unlike past modems, this new one is full-featured and ultimately configurable. However, before I started playing I first simply plugged the old system into the new modem for a test. Just to summarize, old system was ADSL modem -> Linksys RVS4000 firewall -> house network. The initial test system was New modem -> Linksys RVS4000 -> house network. So all should be good, correct?

Before they came I did a Telus speed test. It showed 22.5 down, 1 up, which is pretty good for the 25 plan. The new plan (75) should be 75down, 10up. Once they were done, I ran another Telus speed test: 10up, but 4 down!!! What could be wrong?

On a hunch, based on a bad streaming experience some years ago as well as issues with the RVS4000 a decade ago in a co-locate, I pulled the RVS4000 and re-ran the test: 75down, 10up!

So here’s a warning to anyone using 10-year old technology with faster internet: DON’T. The old crap just can’t keep up. The RVS4000 may have been an expensive device 10 years ago, but it’s brain was an atom processor, which is about 1/100 of a modern smart phone (just guessing!).

At any rate, the little atom processor simply cannot keep up with modern high speed internet. This also confirms the RVS4000 was the problem with streaming some years ago, though I could not pull it at the time to test.

However, the new modem  is awesome. It has wifi that is incredible. My old wifi was a good 10 year old device with big antennae, but devices only ever got 2 bars max anywhere in the upstairs. Now you get 5 bars everywhere, and coupled with the high speed, downloads are amazingly fast.

So all-in-all a great upgrade for $8 more per month.

FLSUN delta printer update for 2017-10-24

Yesterday the new aluminum extruder came from amazon.ca for my delta printer. It was nicely packaged and although the instructions could have been better (b&w photos aren’t great for assembly), they were adequate.

I removed the original plastic-parts extruder and installed the new extruder. It was immediately obvious the mechanism is much better than the original. The toothed wheel is a much finer tooth count, and the idler wheel with notch is much smoother. The spring tension is not adjustable either from close examination nor from the assembly photos, but seems to work in an excellent fashion.

The only hiccup was when I tried to test the calibration. No matter what, I could not get it to extrude. Finally, after much frustration, I realized the two settings in pronterface are not extrude lenght / reverse length, but rather settings for 1.extrude/reverse length and 2. extrude/reverse SPEED. Setting it from the default of 10mm/min to 120mm/min (2mm/sec) was all it took to see some action. Unfortunately the operation was now reversed due to placement of the idler compared to the original extruder.

Fortunately there’s a setting in the configuration.h file for stepper direction which includes the extruder stepper. Flipping the binary option caused the extruder to properly extrude/reverse. Due to the finer gear spacing, asking for 1cm gave 1.4cm. It’s a quick parameter change to fix that and confirm requesting 1cm now gives 1cm extrusion (and retraction).

Finally, I reconnected the filament and tube to the hot end, burning myself severely in the process (2nd degree on a finger which slipped). Once connected I made a test print of the benchy (boat). The first layer is still off, but now at least I can make adjustments knowing the extruder is functioning properly.

Final lesson learned: 185C is VERY, VERY hot. It will cause an instant 2nd degree burn as I found out to my distress. Fortunately immediate cold water followed by ice for 2 hours has reduced the damage significantly.

So… I guess I’m NOT done with Apple

My iPhone 4 is so old now that it’s really getting flakey – freezing up at the most inconvenient times requiring a hard reboot and all that.

So I checked my Virgin mobile plan, and I have some money in the (discontinued) supertab plan. In fact, enough to get a new phone. Now I know there are new phones for $0 on a two-year plan, but I was looking at what I could get for the supertab balance I had.

This is nice as there’s no other way to use up the supertab, so why not spend it on a new phone?

Anyway, it quickly became apparent that Android was out. The phones were either way too cheap, or way too expensive. Besides, I’m not all that thrilled with Samsung phones either as they give you a Samsung mangled Android, not the pure deal.

So what did come up in my search within my (no cost) budget? An iPhone 7. Yep. Apple stuff.

So I went out last week and got it, and it’s actually a very nice phone. More cool, I was able to move all my stuff off the old phone to the new phone in two painless steps as I still have the Macbook available. All I had to do was turn it on, update whatever was out-of-date (including iTunes) and then backup the old phone and restore the new one (data and apps only).

The new phone is, as I said, pretty cool. It’s nice to have something that will last for a few years before getting orphaned again. If the iphone 4 is any indication, that was not really a bad deal for me.

The only thing I had to do was sign up for my same plan for 2 years, which I was using anyway.

So I’m an apple dude again. Kind of. 😉

3D Delta Printer Update

I was not happy with the first prints out of the delta printer. In spite of upgrading the firmware from Marlin 1.0 to Marlin 1.1.3 and running the auto-calibrate several times, things were not as good as I wanted.

One problem was with one axis end stop, which turned out to be loose on the rail. The square nuts (instead of true “T” nuts) was the problem. After much fussing I was able to tighten it, but I think I’ll be buying some proper “T” nuts soon. With that fixed, things were better, but still not great.

I realized another problem was the “probe offset” might not be correct. The Marlin 1.0 default was 0.2mm, but the Marlin 1.1.3 default was 0.7mm. I was using 0.7 and the first layer height seemed high (it wasn’t printing the first layer at all).

Yesterday (Oct 12) I manually calibrated the printer using the paper strip method, then checked the additional distance from “0” to where the probe end stop triggered. It turns out to have a bit of a dead zone. Using the default test height of 315mm, zero was found at 1.13mm. The probe end stop triggers ON at 0.83 but OFF at 0.93. In the middle is a dead zone (0.83) that is either ON once triggered, or OFF before triggering.

As the auto-calibrate uses the probe trigger point, the distance between zero and trigger on was 1.13 – 0.73 = 0.4mm. This was more than 0.2 and less than 0.7 explaining why the auto-calibrate height number was off.

Using the new depth (315 – 1.13 = 313.87) and probe offset (0.4), The prints should be good.

Except they are not.

Watching closely while it started printing, I saw the problem immediately. The bowden extruder mechanism which decouples the extruder from the hot end was not feeding filament properly. Frequently the extruder gear was turning, but no filament was moving. There’s an adjustment wingnut to set the tension, but I found with experimentation that it is just too finicky to work reliably. It seems there is not setting of the tension that will always work first time, and you can’t be fiddling with tension all the time during a long print.

Examining the bowden extruder mechanism, I think I see the problem and the solution. The mechanism is plastic. The idler is a bearing and washers, but the tensioner is just a bolt and wingnut. What is required is a good quality aluminum housing with spring tension similar to that on my cartesian 3d printer that I built.

A quick search on amazon.ca found several excellent choices in the $13 range, so I ordered an appropriate one. It should arrive next week and I’ll resume the testing. I’m quite certain a good extruder will solve the final problems, and perhaps with a final auto-calibrate I’ll be up and running.

Of course, Marlin is now at version 1.1.6, but I’ll hold off trying that until after I get the current version working.

Printer update

I’ve been busy blowing glass the past week or so, so haven’t spent much time with the 3d printers. I did print 8 more weight collars for the weight bench, installing 4 of them last week. They work really well and are easy to print. Printing 4 at a time is easy and takes about 2 hours. What  is even nicer is the new brand of filament is not jamming at all feeding the original cartesian printer, so I don’t have to monitor the print all the time.

The delta almost printed a nice cube. Only the base was off, and on reflection I think it’s because the setting for ‘probe offset’ is too large. The probe offset is basically the distance between the extruder tip touching the printer base and moving enough (into the base) to trigger the probe microswitch. There were two values in the Marlin firmware – 0.2 and 0.7. I’m using 0.7 right now and I think it’s too much, so when you calibrate the printer the final distances are out by a small amount. Not much, but just enough that the extruder is farther away from the bed on layer one than necessary for a proper first layer.

I need to spend some time with raw gcode to find the actual probe distance for my printer and then use that to recalibrate. Perhaps later this week or sometime next week.

 

FLSUN Delta not quite there yet…

I’ve been working with the FLSUN delta printer I built from a kit this week, and although it has printed a few of the test cubes, it’s still not quite fully functional yet.

It turns out delta printers are a lot faster than cartesian (x,y,z) printers, but with that speed comes some rather unique challenges. The first is that the printer, being tripod and pendulum based, really wants to print in an arc. To counter this, the software needs to know a lot of details about the printer, such as segment lengths and arcs in order to calculate various angles and offsets to use when printing.

Fortunately the delta code firmware I’m using (Marlin 1.1) now has an auto calibrate feature that works with the built-in z-probe on the FLSUN delta. Not all deltas have the z-probe, but it’s easy enough to add to any printer. Basically it’s a microswitch down near the extruder that detects when the extruder is near the print bed. On the FLSUN, the switch is triggered by a rather ingenious lever mechanism built into the extruder mount. When the tip touches the bed, it rocks slightly and trips the microswitch. You can fine tune the triggering pressure so that it’s very accurate. There is one compensating measurement you must take, and that’s how much deflection occurs when triggering. That is, the extruder doesn’t just touch the bed, it touches it a bit MORE than when printing to tip and trigger the switch. You need to know (in mm) how much this extra movement is so the software can compensate when calculating actual bed height.

The auto calibrate touches the bed in a set number of places that can be programmed (n*n, with n=4 as default). It can then calculate various angles and offsets that you then either save in the printer firmware eeprom or hand code into the software. I chose to hand code. The default calibration runs until a set standard deviation is achieved, so it’s quite accurate.

Once the auto calibrate is done and the information encoded in the firmware and uploaded to the printer, you can print.

My first prints were terrible. I quickly realized the extruder calibration was off. Extruder calibration is done with auto calibrate but must be done separately. Mine was barely moving, so after some experiments and adjustments, I got the correct parameter (stepper steps per mm of filament) and that was OK.

However, the next several prints were all still bad. I quickly found one of the three end stops that controls the position of the extruder was loose. After adjusting and tightening, things were much better, but there’s still a problem with the print.

The first few layers (about 1mm or so) are offset from the rest of the print in one direction. It’s consistent and repeatable at this time. The rest of the cube is perfectly straight, so it’s a “first layer” problem. So far I have not found any solution on the internet.

One hint that I’ll be pursuing is that the height measurement of the cube is only 19mm, while the sides are both 20mm perfectly. That implies again a “first layer” problem, possibly too hot. I am also considering the fact that this printer is incredibly fast. It’s almost twice the print speed of my first (cartesian) printer. It’s possible that it is simply printing the first few layers too fast, which may also affect the temperature of those first layers.

My next steps are to compare speed parameters between Marlin 1.1 (my current firmware version) and Marlin 1.0 (supplied with the printer) and my cartesian printer (also Marlin 1.1, but much slower settings). I will also try slowing the first layer in slic3r as a quick test. If slowing the initial print speed works, then that will be great. For now it’s a wonderful printer that has yet to realize all it’s benefits (and yet to make it’s first perfect print). 

“I guess I’m not their demographic”… Apple

I just had the most monstrous fight with apple software this week, and had to give up. All I wanted to do was prune my songs on my iphone and ipad. There were songs I wanted to remove that I had installed via itunes on my macbook some years ago.

Well, I couldn’t. Not easily. I finally used the general settings… remove all music feature to clean it up. The only other way was to delete each song individually by swiping left and then touching ‘delete’. Not whole albums, but song by song. How stupid and user-unfreindly!

The worst mistake I made was installing itunes on my Win7 pc. Dumb, dumb, dumb! It worked, but even after connecting the ipad and iphone, it would not let me actually TOUCH the songs. It was so brain-dead that after showing me “songs on the device” it would not delete – the only option was “copy to device”. BUT IT’S ON THE DEVICE AND YOU KNOW IT!!!

Today I blew away itunes. Of course apple left behind a puddle of other crap on the PC that I could not remove via programs. Fortunately I anticipate such nonsense, so before the install I had created a “before itunes” restore point. Using this I was able to recover my PC to where I wanted, not where apple wanted to leave it.

So now I have no songs on my i-devices, but I don’t care. The whole purpose was to use one as an alarm clock playing a random song each morning. Turns out it CANNOT be done via apple. The only way is to jailbreak the device.

As for apple, they don’t want me. They blew off objective-C for their own pathetic thingy called swift for i-device programming. That’s when I stopped app development. Then the recent crop of laptops (no desktops anymore) showed apple’s utter contempt for customers. “You can have light, or powerful, or good screen, but not all in one device. To get them all, buy more devices,” OK, I choose none.

Now the latest iphone is announced at a ludicrous price point. Honestly, the apple price and features list looks like it came from “SpaceBalls, the merchandising”.

Guess I’m not apples demographic anymore. Too bad. I really got the feeling that Steve Jobs understood me, what with us being the same age and loving tech and all. The new apple since Jobs just seems to be about “merchandising to the max”. Sad, really.

Letting the cat out of the bag (3d Printer)

OK, so I’m letting the cat out of the bag. Back in August I decided that I really wanted to try the new delta printers. They come primarily as kits, though you can buy one already  built if you are made of money. I’m not; besides I like building kits.

After much research including print and video reviews as well as many build videos, I chose the FLSUN Kossel Delta printer. There were several delta printers of almost identical value, but I chose this printer for the primary reason that it is “fulfilled by Amazon”, meaning that it comes from a N. American warehouse, not from China. That in turn means that it will arrive quickly. The price was also an incredible deal compared to many others.

It arrived in quick order, and everything was there. It was very well packed, and relatively easy to assemble. I did not make an “assembling of” video because those are pretty similar and all pretty boring, even at high speed. For the most part I followed the instructions to the letter, though I did deviate a few times when I could clearly see a better path. I only had to undo/redo one step, and that only because I wasn’t paying attention to the orientation of the extruder during assembly.

Some of the final steps were less than optimum, in my opinion. Mostly these involved routing and bundling of wires, and location of the main board and power supply. In the end I designed and printed some brackets to hold the power supply securely in a very nice location. I printed these on my other printer. I also designed and printed a spool holder to sit on top. There were available designs on Thingverse, but I really didn’t like them. I do like mine.

I will post photos of the spool holder and the power supply brackets later this week, as well as photos of the printer.

Once together, I did all the set-up, prep and calibration steps.

I still didn’t like the way I’d wired the power supply. I also didn’t like the fact that the power supply did not have an on/off switch, so I bought a switch/cord/fuse receptacle from Amazon (very inexpensive) and then printed a housing for it that sits off the end of t he power supply. It looks great and secures the cord (and all connections) inside the housing. Plus, now there’s an on/off switch for the printer.

I’ll post photos of the switch and housing later this week.

I have yet to make my first print with the printer, but it should happen quite soon.

3D Printing: more designs, fixes, prints and stuff

After printing the regulator flow knob, I was rather pleased with myself. Then the black filament ran out while printing a coaster, so I changed to the new AMZ3D filament I bought recently. I decided to try the white. The spools are smaller, both the hole and the width, so my current ABS pipe holder would not work.

I tried printing “from the box” as I’d done with the MG Chemicals filament, but it didn’t work with the smaller, side opening box. Instead it jerked the z axis at the start of a print and threw off the bed adjustment!

I managed to get that fixed, but took the opportunity to change the bed mount system to now use nylock nuts for greater vibration resistance. While I was at it, I again ran into the mess that is setting the z endstop.

So I decided to design a new adjustment system for the endstop. It uses the same new z endstop I printed a while ago and have been using with good results, but added a screw adjuster.

I designed the plastic to hold the screw using Tinkercad, then printed it. The first one wasn’t correct, but allowed me to see the problem and correct the design. The second was perfect. I mounted it on the non-motor x axis end that rides the vertical bar. One problem I discovered is the screw could not possibly touch the z endstop microswitch. I needed a lever, but turning the screw would spin the lever. I needed a round lever, a.k.a. a washer. Finding a suitable washer, I assembled the z endstop adjustment system and in the first test it worked perfectly. Better than that, it is now easy to make micro adjustments to the z endstop for quick adjustments of the extruder height. Photos attached.

Then I needed a new filament holder. During these test prints, I used a holder I made quickly from a bent metal coathanger (see photos) clamped to the table. It worked but looked like crap.

Today I designed a new spool holder, also out of a coathanger and a length of broomstick, but modified it based on what was wrong with the first one. It works great, and again photos attached.

All in all a great end of the week.