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.

Photos of recent 3D prints

As promised in my last post, here are some photos of the weight plate collar and the new regulator flow knob. Also a photo of the old knob for comparison.

Dacor Fury small knob

Dacor Fury new larger knob

Weight plate collar (the yellow spot marks an original collar)

This is a set of base brackets I printed to hold my PiDP8 kit at a better viewing angle (design from Thingverse)

Glass shop going hot again

It’s time to make some fall glass. Today at noon I started up the glass furnace. It’s a slow process: it takes 8 hours to heat from 100F to 900F at 100F/hour, then 16 hours to get to 1300F at 25F/hour, and then a further 6 hours to reach holding temp of 1900F.

Once it’s at 1900F, I’ll start charging with raw glass batch. The batch I use is Spruce Pine, or SP87 which is the classic batch for glassblowers. I should have a fresh pot of clear glass early next week. Then it’s time to make some nice things.

Still designing and printing

I made a few things this past week, and designed (and made) a few others.

First, I didn’t like the stark white of the new Dacor Fury flow adjustment knob, so reprinted it in black. I also flipped it so the square hole was on top for a better print of that side. When done it fitted perfectly and has already been tested in the water. It works perfectly.

I loaded cave line onto the dive spool and also took it in the water. It held up perfectly but time will tell how it holds up.

I also designed and printed a replica of the weight plate ring for my weight bench. The ring is a complex plastic part that sits in a hole in the weight plates and keeps things from banging loudly when in use. Each plate requires three (on for the center bar and two for the side slide bars) and many were missing or broken when I bought the (used) weight bench. I tried contacting the manufacturer in eastern Canada, but the bench was made in 1995 and they had no records for it at all! I designed one in Tinkercad and it printed perfectly. It’s now on the 50lb plate so that it can get some everyday use to see how it holds up before I print more.

I also designed and printed some clips for the cats’ litterbox. It’s 10 years old and the originals broke. The printed ones fit perfectly and so far are holding up very well.

Finally over a week ago now I designed some small plastic ‘buttons’ to cover assembly holes in a set of drawers Linda bought for her sewing room. You know the ones – the small white plastic 1/2in buttons that go in the screw assembly holes in pre-pack particle board furniture. This one was missing all but one (of 8) so I used it as a template to make 9 new ones. Some had to be white glued in place as the holes had enlarged, but all are on now and look great.

I notice that my photos weren’t ready for uploading, so I’ll add them soon. (New reg knob, loaded dive spool, weight ring and litterbox clips).

 

Lastly, some news on filament. The white AMZ3D filament was working very well, with only occasional snags. Thinking about it, I realized the spool did get loose during the coathanger holder creation. I decided to open the AMZ3D black filament and be very careful loading it. As a result, I’ve been able to print many things, some with over an hour print time, without any snagging at all. It would seem that a) this AMZ3D filament is awesome stuff, and b) loading procedure is critical – you cannot get any loosening of the filament when loading or you will get snags. I really like the AMZ3D white, but I absolutely love the AMZ3D black. I even ordered another roll.

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.

Awesome 3D Print

OK, I’m brilliant.

I have a SCUBA regulator that’s missing the flow adjustment knob. Years and years ago (2006?) I bought a primary second stage for my open circuit regulator set from a shop in Calgary. I got it for $100 even though it was brand new because someone unscrewed the flow adjustment knob and then lost it. I’ve been diving it that way ever since because you could not buy that knob for love nor money.

Last night before I went to sleep I thought… “why not 3d print a knob?”.

The knob fits a square shaft 7mm x 7mm x 2mm and is sized to match the regulator. It attaches with a 3mm  stainless hex bolt. Today I designed and printed the knob, and with a bit of drilling to open the bolt hole, it fits and  works perfectly.