A Sick 3D Printer

Yes, the printer was sick. But it was my fault.

When I was done with PETG testing I pulled the filament and pushed through some PLA to clear it out – only I couldn’t push the PLA through. The PETG had broken off and there was now a clog in the hot end (the nozzle, heater, and the other associated stuff). No problem – I’ve seen the video on how to disassemble it and put it back together. I did that, got rid of the clog, and put it back together.

I should have watched the video again – I reassembled it incorrectly and didn’t get things properly seated together. As a result I had plastic oozing out all over the hot end making a mess and dripping plastic chunks on my prints during the printing process. It took me a couple of days to realize what the problem was and since I discovered it late in the day I put off fixing it until the following day.

I started tearing it down again and found that I was going to have to order a part. There is an insulation wrap that goes around the hot end block (a chunk of aluminum with the heater in it) and it was gunked up with plastic. It would be hard when cool and then a dripping mess when things got hot. I know where to order it so I place my order (minimum order is 2 of course) and wait about a week to get the part. In the meantime I start cleaning up the rest of the mess.

The nozzle threads were gunked up with plastic. The heat brake threads (screws into the other side of the heater block) are gunked up. These cleaned up pretty easily with my Dremel with a wire brush.

The threads inside the heater block are gunked up. The obvious way to clean this out is to run a tap down it. Do I have one? Of course not – it’s metric M6-1.0. I start hunting for one locally and find several possibilities. Menard’s listed one (and only one) in the store so I went there. Nope. It’s slot is empty. I knew I could go to Lowes but I thought that Oriley’s across the street just might have one. They did but it came with a drill bit (just like Lowes) – and a higher cost. Oh well, gotta have it so I bought it. The threads inside cleaned up nicely.

I had to remove the thermocouple temporarily so I could get the insulation wrap off. It’s held in by a silicone sealer. Not your normal silicone of course – high temperature stuff. Some research found the right stuff – the kind used to make gaskets on auto exhaust pipes. Of course it’s an auto parts store item and the tube would be able to do about a thousand of these things. I only need one drop. Probably one more tube of stuff that will be hard as a rock the next time I want to use it for something. Of course I have to wait 24 hours (maybe a little less) for it to set up properly before I can move on to the next step.

Now to clean off the block itself. Heat it up to 100C (that’s 212 Fahrenheit) so the plastic would get soft. Of course it’s now HOT and I have to hold the block with pliers and scrape off the gunk.

Time to rewrap the new insulation around the block and start putting this thing back together. The PROPER way to put the nozzle and heat brake together is to heat things up to 240C (464F) and screw in the nozzle, with my trusty 7 mm nut driver, snug and then back it out about 1/4 turn. Then you screw in the heat brake snugly (quickly before it gets too hot). Then TIGHTEN the nozzle firmly up against the heat brake. Then it’s time to let it all cool down so I can put everything back together.

Want to see what I’m talking about? Click on this YouTube video link for an explanation. It’s actually a different printer than mine but the hot end is identical to what I have.

I printed a test cube and it came out fine. I’m printing a stamp dispenser as I type this and when I left it about an hour ago it was doing fine. It’s a 2-1/2 hour print so it’s about time to check it again.

That’s all for now.

Advertisements

So Where Have I Been?

I know, I’ve been lax on posting updates. This will be a long post.

3D Printing

I’ve done a lot with the printer. I have some pretty good settings that make printing pretty reliable. I’ve printed a bunch of stuff, some useful, some just fun. I’ve bought more filament including one spool of PETG (everything else has been PLA). I now have Silver, Red, Blue, White, and Black (PETG). I know I need a few more for variety but I think I need to wait a bit before ordering..

My success with PETG has been variable but I think I have it zeroed in now. More heat (required) but none on the build surface. Cover the build surface with 3M GREEN painter’s tape (used to stick on concrete and such) and all goes well. I wasn’t able to use the blue tape because it would curl up and unstick itself from the build surface. The green stuff sticks well but has an odd smell. The PETG itself seems to be odorless which makes it an easy choice over ABS. They both have similar characteristics. I’ll be using the PETG for special things only.

I’ve been ordering filament from MatterHackers and have been pleased with the results.

I’m going to get some photos of what I’ve been doing in the next post.

Cuyahoga Falls Amateur Radio Club (CFARC)

About 3 years ago I parted from the club. I was a member since early 1998 and had been heavily involved with various activities including handling of the web page.

I got a desperate call from one of the members who had been working on a new web page for the club. He tried something and then thought he put it back but something went awry. It took me a while but I finally had one of those ‘A-HA!’ moments and fixed the immediate problem.

There were other issues and I decided that I could help out a lot with some of the areas where things seemed to be falling apart. So, I’m back with the club now working on the Hamfest and web pages. I’ll no doubt get involved with other things but I’m going to try to keep it down a bit from what I was doing. Although I love Field Day my participation is not going to be at the level I had done in years past. I have to draw the line somewhere.

Promises …

I have been pretty busy lately but that’s no excuse for not putting more in here. I’m going to try to set up something on a more regular basis. I’m going to try for twice a week on as yet to be determined days.

3D Printing – 5 days later …

I’m having a blast with this thing. It’s not always gone well. There have been problems. Solving problems is what I love to do so I’m having a great time.

Several prints later I’m still liking this printer. I wish it had a bigger build volume but I knew that would be an issue at some point. I figure that if I really need something bigger that can be covered in the next printer. No time soon for that though.

I now have 3 different filaments, all PLA and in 1 kilogram spools:

  1. HatchBox PLA in silver. This is working well and gives off hardly any odor (all PLA filament has some odor – not objectionable or really toxic). The color is great as it gives off a bit of a sheen. I like it and would buy more without hesitation.
  2. PolyMaker PolyLite PLA in red. This also works well and gives off a bit more of an odor. Red is of course an important color and I’m glad I have it. I did have a couple of broken filament problems. The first one broke off right at the extruder and I had to pull the Bowden tube from the extruder to get enough filament to grab hold of to pull it back. The other break left a big enough piece to actually print something with so not too much wastage. I probably wouldn’t buy this again as it’s a bit more expensive ($25) .
  3. MatterHackers Build PLA in blue. I just got this one so I don’t have as much experience with it. It gives off the least odor of the three. It looks though that this may be my go-to filament. Unless something really turns up against it this will be it. The price is $19.99 like the HatchBox but I can order directly from MatterHackers instead of through Amazon.

I’m printing a ‘3DBenchy’ as I write this in the MatterHackers blue and I like the color. It’s about half way though right now and is looking good. I’ll add a paragraph at the end when it’s finished.

This is the first print using a new version of the slicer Cura 3.6. I was using 3.2.1 and it was working OK and I had most of the settings tweaked pretty well.

What’s a slicer you say? It’s the software that converts the 3D drawings into the command code (gcode) for the printer. If you look at the gcode you can see EVERY little step the printer has to do to print the drawing. For example, 3DBenchy has over 212,000 lines of gcode.

The 3DBenchy finished. It looks really good – very little stringing and few other flaws. The new one is on the left and the first one I did (my second print) on the right.

img_4663

The notepad these are sitting on are my semi-detailed notes for printing. I’ve been documenting everything I’ve been doing so I don’t repeat something stupid I’ve done before.

The stringing test I just ran came out CLEAN! I think the Cura upgrade did some tweaking as well as some of my own. Anyway the string problem is solved at last.

I’m printing a Gearicon (7 tooth) in the MatterHacker blue to go with the one I printed yesterday in red.

I think that’s enough for today. I should post more often so it doesn’t end up so long.

3D Printer – First Prints

My first shipment of filament arrived today via Amazon (on SUNDAY which will not happen again). It’s Hatchbox PLA in silver. Quite nice looking as it has a bit of sheen to it’s grey overall color. No issues using it. My only problem is bagging it back up because it won’t fit in a normal 1 gallon zipper bag. A temporary trash bag will have to do.

I printed off the “cat” that came on the original SD card and it worked just great. Being paranoid on the first print I was checking it every 15 minutes to see how it was doing. Just a bit of stringing which is easy to resolve with a quick once over of the heat gun. I’ll look at ways to solve that later. It took about an hour and a quarter.

The next print was the 3DBenchy – the standard benchmark print. This was the first print that I had to ‘slice’ myself from a 3D drawing file. The ‘cat’ came pre-sliced so it was ready to go directly from the supplied SD card. I had some difficulty and it’s not right yet but there is hope. The standard settings don’t seem to be quite right to set up the starting elevation and it appears that the printer is trying to print below the surface of the bed. When this happens filament can’t extrude properly and things just kind of oozes out the sides and all over. The third try I got it much closer and it looked like it was going to print OK so I let it go. Print time was 1 hour 50 minutes.

I was taking photos and short videos while doing this and I’ll post some of them up on my next entry.

My next box of filament should arrive tomorrow. I’ll use it to print my first modification to the printer – a filament guide so that the filament doesn’t rub on the side of the printer. I have a couple of other things to try out too.

3D Printer – It’s Here!

I decided a few days ago that I was going to buy the Monoprice Mini Delta. I also decided that I would wait until after Christmas to place my order – no point in jamming up the rush with all of the other packages in transit.

So, I ordered it around noon yesterday (26th). I was notified that it was shipping from Kentucky via FedEx Home Delivery. It showed up TODAY (27th) BEFORE 10 AM! I was planing on spending part of the day clearing off my desk in the library (a flat space with lots of office type stuff covering it) for the printer. I’m still finishing that up and should be done soon so I can at least unpack the printer. Gotta check out to make sure the lights at least come on.

I also ordered filament from two separate sources. One from Amazon (Hatchbox PLA – Silver) which has not yet shipped and the other from MatterHackers (PolyMaker PolyLite PLA – Red) which will enter the USPS mail stream later today.  It’s supposed to ship Priority Mail so it will no doubt get here long before the Amazon order even though I ordered from Amazon on Wednesday and MatterHackers on Thursday.

MatterHackers is out of stock on almost everything right now and the PolyLite is a bit more expensive than the Hatchbox but it gives me a chance to try out a couple of known good filaments. I’ll no doubt be ordering more and I think it will probably be from MatterHackers. Hopefully they’ll have replenished more stock by that time so I can order some Blue and Black filaments.

It will probably be at least Saturday before I can actually try out the printer. I’m HOPING that it will come in on Saturday but considering it’s coming from California I’m not going to be that disappointed if it doesn’t.

 

3D Printing – Checking Out What’s Out There

From time to time I have wondered about 3D printing and have never really carried it much farther than the wondering part. This time I got a little more serious and started some investigation.

I’m thrifty (cheap) and I don’t really know how much I would get into this so I kept my investigations to the low priced printers. I looked at 5 (so far): Creality Ender 3, Monoprice Select Mini, Anet A8, TEVO Tarantula and Monoprice Mini Delta.

All except the Monoprice Mini Delta are cartesian coordinate (XYZ) printers. The Mini Delta is a different animal in that it uses the delta style (use your favorite search engine) of positioning.

Each of these printers have their own issues. Some more than others but none of the issues are things I couldn’t resolve myself. There is LOTS of help out there about the issues and how to solve them. Often they involve printing replacement or supplementary parts on the printer itself.

Do I have a favorite? Of course! It’s looking like the Monoprice Mini Delta is going to be the winner for several reasons:

  • It has a heated bed. This makes getting the part to stick to the bed easier.
  • The bed is auto leveling – a necessity for any delta style printer. This is a time consuming manual process on the other printers.
  • It’s faster than all of the others mostly because it uses the delta system.
  • It’s fully assembled out of the box. The others, except the Monoprice Select Mini, are kits. REAL kits with a pile of parts and various levels of instructions for assembly.
  • The frame is all metal and quite rigid.

Does it have flaws? Of course! It doesn’t have an on/off switch (stupid but easily solved). The bed size is small but I wasn’t planning on printing anything big anyway. The main board fan is overly loud. It has problems feeding non-rigid filament stock. It requires some tweaking of the software slicer (pretty easy to fix).  The wifi interface is unreliable but I probably wouldn’t use it anyway.

All of these things (except the print size) are fixable or can be ignored (wifi).

All of these printers can print with a variety of materials such as PLA (by far the most popular material) and ABS. PLA (polylactic acid) operates at a lower temperature and is easy to work with and inexpensive. ABS (Acrylonitrile butadiene styrene – LEGO bricks) produces much sturdier parts but needs higher temperature and gives off nasty fumes.

I haven’t bought a 3D printer yet but with this much research (several days now) and the itch to buy myself a Christmas present you know it can’t be long now.

Traffic Circles

I can hear it now – “I hate them!”.

You’ll have to get over it. More are coming every year. They provide for increased and quicker traffic flow when used properly.

How often are you at the front waiting to enter the circle only to have someone exit leaving a nice gap – but you weren’t ready. You didn’t know you were going to get a chance because they didn’t use their turn signal.

Traffic circles work best when the flow of traffic is smooth and continuous. That only works if drivers exiting the circle let other drivers know they are exiting. If you have ever been through Tallmadge circle in rush hour you know it can work pretty well. That’s because people who use it then have learned how to use it properly.

I know there’s more to it to make it better but good communication is a good start.

So don’t be afraid of traffic circles – and use your turn signal.