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JohnInOttawa

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Everything posted by JohnInOttawa

  1. Good morning! It is a balmy -25C with the windchill outside, so what better time to concentrate on the indoor to do list? My usual disclaimer: I'm clearly not an engineer. I work in the end of the field that tries really hard not to break the nice toys that the engineers design for us. As I look at the growing variety of materials and prepare to set up a test environment, I was looking at the torsion boxes I've built to hold some of my heavier equipment and began to wonder - I know that infill works on a very similar principle, but if I am aiming for the strongest, truest surface to withstand loads at the lowest cost, can I expect (and predict) strength and performance improvements for given combinations of infill and skin materials? For example. We know that PLA can be very stiff but isn't particularly strong on its own and subject to longer term 'embrittlement' (pardon my abuse of the term). But what happens, say, if we embed a PLA grid inside a nylon/CF box skin? The skin provides stiffness and protection from UV, while the PLA should, in theory (depending on print orientation), serve pretty well to support the central area of the box against compression loads. I recall that some torson boxes use corrugated cardboard for their internal structures and achieve amazing load bearing capacities. Where am I going with all of this? Some of the newer materials provide us with new levels of strength and stiffness - but the cost makes using these for larger prints a serious challenge. If I was able to use an exotic filament for the skin to protect a less expensive but adequately strong matrix (and my question is really about determining 'adequately'), then all of a sudden these new materials start to look cost effective for a broader range of applications. Looking forward to your thoughts! John
  2. Depending on what the thread is for, I often have a mate in metal somewhere. In that case, once I clean up any strings or tags, I'll run the metal complementing thread (bolt, nut, camera filter, etc) and use it to 'chase' the thread more accurately. I've had pretty good luck doing this. One thing that I have had bad results with is using PVA supports with threads. The PVA just messed up the thread layers so it looked like a comb from the side. Better to go with no supports in that case. Best of Luck! Cheers John
  3. Welcome! It may take a bit more information to get a reliable answer to your question. For example, are you intending to print a mold or an end use product to rest in the eye socket? If the printed part itself will rest in the eye socket, my main concern would be infection control. I have not seen any FDM-produced surfaces that are smooth enough (totally free of surface defects or lines even at the microscopic level) and non-porous enough for such an application. That said, if you can provide a bit more information about your research and testing setup, there are some manufacturers here, with any luck one will engage and get you some useful info. John
  4. Thank you @Labern! I have reached out to George to see if I can extend from his work in any way. I won't presume to have his level of test capacity or knowledge, but if I can at least make what I do relatable in some way to his work, perhaps it will add to the body of knowledge. I also agree that there are many facets to what makes a material right for a job. I have heard from another member here that some of the characteristics that make for an excellent matte surface finish may resulting in something too rough for regular skin contact. I don't know yet how I will evaluate that. I am thinking about setting up a block of soft pine and seeing how much sawdust I can raise with the surface of each printed part. High texture might be very desirable for rough service parts where maintaining grip in wet or greasy conditions is key, whereas braces or other body contact parts might need something different. WRT to dimensions and stringing, here's where I am throwing myself on the mercy (or knowledge base if you will) of the group and your post is an excellent example of what I was hoping would happen. While I can't guarantee I'll have the capability to do the kind of testing everyone requires, the chances of me getting close are better with this kind of input. Much appreciated! John
  5. I'm happy to take input on an appropriate test model and will share the STL for that model once it's finalized. Now, I am not a test lab, so apart from maybe bringing in a force gauge (I'm thinking a 500# limit should do it), I don't want to create the impression that this is going to be high science or engineering. But now you've given me an idea, there is a proper materials lab at the nearest university and I may still have a friend or two there. If I can set that up then I'll happily accept parts printed in your preferred material. Hmmm. What are the odds I can find an engineering student interested in testing a whole bunch of things to destruction? Nah, they'd hate that...;-) J
  6. @P3D, I appreciate your help! While you're a long way away, your perspective as an active user of markforged onyx is valuable. I did ask Markforged if they could provide a pure Onyx part, no go unfortunately. I am told that they will send a nylon and an onyx/CF reinforced part, so we shall see what shows up. I'd like to know more about your experience with the Markforged, but as that would be somewhat OT, may I PM with some questions? Cheers John
  7. Yes, it is a long way from the plywood Ultimaker Original (one of which sits next to my UM3) that started this community. It's tough to be all things to all people, but it does seem to me as if there is a shift occurring here. As the angst over the Cura upgrade and S5 reliability attest to though, with a new market comes new expectations. We will all see how this plays out. J
  8. Ha! I feel better already - while still feeling too poor.... ? J
  9. I see the announcement that the CC Red is now shipping. This was my first chance to see the price. With great respect for all of the work your team has put into this product, I have to say I can't afford a $385 (CDN) print core. That's more than double the price of the other AA cores. I may feel differently after some longer term experience with the hardcore/everlast combinations, we'll see, John
  10. Thank you @P3D. I see it the same way. That adds some clarity to the capital plan. The entry barrier for the continuous fibre machines like the Mark Two or X7 is high enough that either there is a clear business case for keeping those machines operating effectively at the price of their consumables, or there isn't. As the printer costs drop (not to say Onyx is cheap, because it's not), the issue gets murkier, especially when one starts saying no to work. Would there have been enough to justify the lower cost printer? Maybe is the answer more and more often. If this test works as I hope, that question, at least, will have an answer. Thanks again! John
  11. Thank you Adam! And a direct thanks to the Owens Corning team for these samples! The tech data is very helpful. What I'd like to propose as a plan, once we have some candidate designs, will be to circle back to you guys to optimise the print settings and strategy. Thanks for your offer of support! Cheers John
  12. That helps tremendously! For sure, the addition of continuous fibre reinforcement is a game changer and Markforged has the success to show for it. Your commentary on Onyx alone speaks directly to this comparison though and adds an important consideration - how long will the part retain the properties it held at the time of printing? If XSTRAND produces better results than straight up Onyx, then it means the holder of a (modified) UM3 or an S5, or for that matter any printer that can handle the Owens-Corning product, should, in many cases, be able to produce the same results, or better than the MarkForged Onyx One printer (which cannot incorporate continuous fibre). I say 'many cases' because there are additional features like the ability to remove and replace the table while embedding parts, etc that are still rather unique and might be required for a given print. For a small shop like mine that gets request for Onyx parts more and more these days, being able to offer a truly equal or better result without the capital cost means being able to compete in a new market with a printer that, unlike the Onyx One, can print with dissolvable or breakaway support, or alternatively, mixed materials (as @SteveCox3D illustrated in one of his excellent posts). Much appreciated! John
  13. I hope I'm not practising bleeding here, but I got the hardcores to print the nylforce with is also nylon/cf,so they should hold up. If I wear out something, it should just be the nozzle, which in my case is replaceable. Yeah, I hear you on cost. That was the main reason for my request for a sample. If it makes the difference and I can justify flowing the cost to a client, then it's great to see the advance. I'll look forward to seeing how you make out with the Zytel. It sounds like getting the printer to play nice has been a challenge. J
  14. Good warning on the wear factor. I'll go with a 3dSolex HardCore with an Everlast (Ruby or Sapphire) nozzle, and the feeders are upgraded, so I am told that should avoid any issues. That said, it likely won't be a dead on match for the CC. John
  15. Well, true to their word, the Owens-Corning folks sent me two 50g samples of XSTRAND GF30, and PA6. And fast! Thank you! Now, I believe I was asked on this forum to post results. I intend to do more than that if I can. As this is an open community I'd like to leverage your smarts to help me compare this material properly. Here is what I have on hand to compare - PLA (I think that will be not be a contender but will be used for a mockups and test prints) -Ultimaker Nylon -Taulman T-glase -Nylforce CF Keeping in mind that I only have 50g of the XSTRAND to work with, I'd like to get this right on the first try if I can. Owens-Corning has a UM3 so I'll apply their print setup recommendations for the XSTRAND. My own UM3 will be modified with BondTech DDG feeders and 3dSolex Hardcore with everlast nozzles. So a bit different than the S5 with CC Red, but I hope close enough. Sadly, I don't have access to anyone printing Onyx on a Markforged at present, but if I'm able to make that connection, I will try and see about getting the same shape printed and used for the trial. Timing - this will take a few weeks, just due to other demands. All that to say, there's no rush. I'd also welcome thoughts on testing strategies. I can apply a force gauge, but the range is the thing. How much force am I expecting this part to withstand? So, thanks in advance for your help! John
  16. Clearly you folks have a business to run and these are business decisions. Fair enough. That said, Cura restricts printcore selections to only Ultimaker provided options, so it tends to backdrive the demand for as much capability in these options as possible. As an alternative, what about allowing user-specified printcore configurations? For those of us with 3rd party printcores, it would be nice to be able to specifiy a nozzle size not offered and might take a bit of pressure off your development team. You can concentrate on the configurations that make sense for you, and users with corner case applications can do their thing. For your consideration... John
  17. Your costs would be less than mine as it looks like you are in the US. I got everything from the gr5 store, he's on this forum. I found the pricing as good as it got and service was fast, even transborder. I'd recommend him. https://thegr5store.com/store/ John
  18. Good afternoon. I have just gone through the mod process, not saying what I did was right, but I have heard from a filament maker that it will work and prevent damaging wear on my UM3. The stock AA printcores cannot tolerate abrasive filaments for very long. The first thing needed is to acquire a hardened printcore. The second is a hardened feeder. I went with a 3dSolex Hardcore printcore AND everlast nozzles with ruby or sapphire. I tend to use a 0.6 size as it seems less likely to clog, but I bought a wider range as it made sense with shipping. Ultimaker has just come out with the Print Core CC Red, specified for abrasives, but I don't know how hard that will be to get. Likewise, the stock UM3 feeder uses drive components that cannot tolerate CF, whereas the S5 feeder is made of hardened material that can. My solution was to buy the BondTech DDG UM3 upgrade. There are two BondTech offerings, you can decide which is best, both are hardened for CF. I have some nylon/CF on hand and am setting up to test another brand, but haven't done anything worth reporting on yet. Others here will likely have some better experience to share. One final thought - if you decide to start out with nylon/CF as I have, you may want to invest in a filament dryer and a drybox to keep the filament as dry as possible during printing. The nylon substrate is very prone to moisture absorption and its impact on print detail and adhesion is significant- probably the only plus side of cold Canadian winters is that I can look forward to easier printing as the house humidity plummets ? Hope this helps! John
  19. This discussion reminds me of a very different situation. I once had a fellow working for me who had, by all accounts, limitless potential. But almost every project he got involved in ended up with high drama situations where people were storming out of the room. I was called in to referee and try and get my staff to back away from defcon 1. It turned out that 'limitless potential' created unique focussing issues. There was never one direction that the guy would settle on. The team would agree on something, charge off in a direction, only to have this fellow rip it all down because he no longer felt it was optimal. There was always a better idea, and the cycle repeated until everyone else exploded in frustration. In the end, I had to pull him off of some of the key, time sensitive projects and look for safer spaces where he could contribute. My director called me in, 'what the heck are you thinking? He's the smartest guy you have. Limitless potential'. I said the first thing that came to mind - 'you know, lightning has just about limitless potential too. But just try to power your house with it.'. At least he laughed before kicking me out of his office, but he got the message. In this setting, there are so many ways an Ultimaker can be used, each one of them with an expansion or enhancement branch. I don't know how you corral all of that into a corporate strategy without turning your entire staff into something that looks like a transporter accident. All I can do is cheer you on and hope you guys get some breathing room. All the best John
  20. Hmmmm. @ctbeke I don't know you, indeed I have never actually met anyone from Ultimaker face to face. But your comments to Kman have really struck a nerve. I don't think it is a personal choice you are making. My concern is regarding the entire crew of the good ship Ultimaker. I am reminded of a very old conversation- 'this job would be so much easier if not for the customers'. Spoken to me by a harassed company owner just before his enterprise imploded. While it has been a rough ride on a number of fronts lately, and I would not presume to advise you on technical details of your products, allow me this - your customers' expression of frustration is not something to be pitied. It is something to be studied. There is as much data there about what you should do next as there is in the system logs you are receiving. In the airline business, the most dangerous time in the lifecycle of a company is when it is expanding. That is when unrecoverable business errors like permanent customer relation fiascos, unsustainable capital projects and loss of the core clientele while courting new frontiers are most likely. None of these steps are done intentionally but are often reactive. There is even a model that describes this. Maybe unrelated, but those in my business will know this - the first sense to falter during a task saturation event is hearing. When I see what is taking place on this forum, I wonder about a parallel condition - have you guys perhaps been in overdrive too long? There has been aggressive expansion on a number of fronts lately. A new printer, new materials, new print cores, new Cura. Likely a number of things I have missed. My hope, and I speak only for myself, is that Ultimaker leadership recognises the need to downshift and give the creative staff a shot at stablizing the products now out in the wild. Part of that is going to require giving your interface staff enough time and resources to listen, and then listen some more, without reacting, until the whole story has been told. Then start to dampen down the oscillations until the line is flat. So an early holiday wish for you - that you guys get the time you need to do what you have to do, and recharge a bit. John
  21. Thanks! While we're on the subject, I have a nylon print coming up later today, support would be good but my last PVA attempt at that wasn't great. Have you tried PLA as a support with Nylon? John
  22. FWIW I no longer use any support strategy where PVA rests atop PLA. Everything has to touch the build plate or I use a different support material. Just too many problems. In my case, I put the PVA in a dryer before and after every use, never hear sizzling or popping so I am pretty sure it's all dry. I think it's just a finicky material and the BB core takes careful management to avoid clogs. I'm sure others have a better technique. Perhaps breakaway would be a better option, but I haven't picked any up yet. John
  23. First off, thank you for organising this AMA. This was my first chance to participate in one and I found it really helpful on a number of fronts. One question I meant to ask and just did not recall on the day, was, has Owens Corning run any comparative analysis on their product vs Markforged Onyx? I appreciate that it would be hard to do this properly as the Onyx product would really have to be printed in the Markforged eco system for a fair test. That said, it occurs to me that an apples to apples comparison would greatly clarify the case for choosing an Ultimaker S5 (or UM3 with modified feeders and print cores) over a Markforged Onyx One. Probably the biggest single capital decision I face in the next 18 months, as I consolidate some of my CNC processes, is whether I can economically produce a true, equivalent-service-life additive replacement to a CNC'ed part. At present there aren't a lot of competitors in the continuous fibre reinforced printing, or office based metal printing, but then the bulk of what I do doesn't need reinforcing. So, for nylon or plastic based parts, If XSTRAND can do (most or all of) what Onyx does, then Ultimaker wins with layer height, dual extrusion and swappable print cores so I can move on to the next job with the same unit. Is there any way to route this question to our XSTRAND gurus? Thanks in advance for any help you can provide. Cheers John
  24. If you happen to run into issues with the backslashes being interpreted as control characters, there is os.path that will allow you to build this string correctly. FWIW J
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