New printer time?

This is why I’m excited about the next lowrider revision. I really borked mine up cutting corners, but wifey wants a full sheet machine in the new shop.

Tangentially related(to the thread, not Ryan’s design) …mdf seems less prone to catching fire. Is it just me?

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mdf smokes and smolders more, but once the dust catches, it goes off like gun powder.

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Guess I just need to try harder :grin:

No, try dumber, not harder; take the bag out of your dust collection and get as much MDF dust up in the air as possible, then introduce flame…

Reminds me of my childhood home, where my room was the first second-story structure on the sight-line from a grain-bin.

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That is the best thing I have ever seen :laughing:

Did you go to MRRF this year Barry? I am sorry but I forgot to tell you I heard one of the guys on a podcast say, tickets are sold out but they would not turn people away at the door. They sent me no information whatsoever except in like January asking if I wanted a refund for last year’s sponsorship or just carry it to this year. I carried it forward but received no other info.

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I was going to rebuild and enhance my MP3DP. I like the inductive proximity sensor on the Prusa i3, but some other enhancements ideas are to

  • Embed E-Z Lok(s) in the bed for the screws/springs to go through. Getting those nuts on is a pain.
  • Use a T5 lead screw with a small stepper to raise and lower the Z-Axis stepper (with a coupler), essentially a worm gear built into the left Z-Stepper bracket. Getting to the screw is a pain and requires raising the Z-axis to get to it for every small adjustment.
  • I have also been think about ways to adjust the bed screws from the bottom (using the same stepper and some printed parts), and making room underneath by increasing the base height.
  • A removable extruder would be nice, even with screws, if you had an easy way to take it off and clean up jams. Maybe use a pluggable connector like this one (actually manufactured in Germany), vs. the very expensive embedded conductors (which I considered at some point).
  • The removable beds are nice.
  • I also considered using sensors to measure the platform and X-Axis tilt relative to each other.
  • A built-in filament sensor would be nice in the extruder with a more straight feed and dual gearing like the Hemera. Or just allow the Hemera to be used.

I would love if my next printer could print up to 3-4 different materials at the same time, one of them being a gel (not a hotend).

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Nope, last I heard they weren’t letting anyone in without a ticket.

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I know what a bummer. I really hope they get someone to deal with public relations. In the podcast he said something like the most unorganized, organized event. I don’t really agree with half of that statement.

My 2 cents…

I would love to build a printer with a stationairy bed. So a core-xy is a good choice. How about a bit of Voron with a Ultimaker-style wooden enclosure…
Perhaps the x-y axis with Aluminium extrusions.

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i kind of get it. The “cool kids” are using aluminum extrusion and getting fantastic results with it, but take a step back and think of what the extrusion is for.

In a nutshell, it’s for precision placement of the fittings in it, and for getting nice square corners, for when you don’t have say, a CNC machine to get that precision.

The aluminum extrusion is not and was never intended to be an inexpensive solution. It was meant to be a solution for those who want a platform which can be used as a basis for precision fittings with relatively low weight and good rigidity.

With a CNC router, we really don’t need it. There is no reason whatsoever that we can’t get as good or better precision, nice square corners and excellent rigidity with lower cost materials, once there is a CNC router in play, assuming that the CNC router is properly squared up.

If you want the aluminum structure, we should be able to use 3/4" square tubing, which is readily available, and much less expensive than 2020 extrusion. More importantly, it doesn’t depend on the T nuts and fittings that get stupid expensive really fast. For less money you can buy thread taps for common bolt sizes and use those to fasten everything together. Or instead of tube, use angle. This can be thicker, and you can have easy access to the other side for nuts or other fasteners. With a CNC machine the options are much greater

So in terms of a CoreXY mechanism, which is really cool, and keeps the moving mass to a minimum, resulting in better possible speed and precision with less ringing and other artefacts, we have some nice lightweight options that are superior to extrusion available to us simply because we have some tools available to us that most printer builders do not.

Being able to (for example) put holes in a piece of 3/4" aluminum square tube every 25mm to bolt a piece of MGN12 linear rail to will give very similar options to a piece of 2020 extrusion, but at about a third the cost, before even getting to the specialty fasteners. Or put those holes in a piece of 1/2" MDF for the stationary rails.

I don’t mind the bed moving in the Z axis, but for sure, my next printer design isn’t going to be a bed flinger.

I’m going to go for something that can compete with the guys who are putting out 4 digit price tags for print quality, but stay as far as I can away from things that are needlessly expensive.

I see extrusion profile as something that is a substitute for better tools, except I think that the Primo/LR2 are the better tools.

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You’re a thinker, ain’t ya?
Those are all really good points, though, especially the thoughts on angles vs extrusion.
As for placing holes with the cnc in the enclosure, that’s exactly how I did my last one to locate some printed parts, and I was just tickled at how well it went together. It really is a step above extrusion frames imo, and I don’t think i can say that emphatically enough.

Well so far it is actually pretty easy to design for both. For a printer you only need three planes, from there know that extrusions are 20mm on center and that is done. As long as you do not wrap corners it translates flawlessly, wood doesn’t care where the holes will be. So three planes…multi frame material compatible, done.

I am close to assembling a test machine. Don’t get too excited I am trying a few new to me things. One of which already has a shortcoming, just not sure how big of a deal it actually is.

I still lean very strongly to non-extrusion, but you know what it does well…quick accurate prototypes. Isn’t that what it was designed for? When I have it ready or a lot closer I will start popping holes in wood instead of all these dang t-nuts. Just working on the last tensioner part and some sort of tool mount layout.

Oh, I have a serious question. When people use these linear rails why the heck do they put a screw in every single hole? I can’t see needing more than 3 screws in a 300mm-500mm run. Am I missing something?

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I’d guess it was to ensure against either lifting or shear forces perpendicular to the rail causing deflection.

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What do you put in the extra holes? :slight_smile:

If the rail is rigid enough, 2 would be great. I definitely had it slightly twisted when I first constructed and the tight tolerances made it sound funny. I loosened everything but the two outside ones and then clamped it back down and it worked after that.

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Because “more is better!” Personally, I think it’s a recipe for bending a rail under thermal stress, but what would I know…

Edit: I remember one person describing it as the combination of the 2 parts being stiffer than either one by itself, so basically more points fastened down meaning more stiffness. I still think that it’s asking for stuff to get bent, and if something is exerting enough force against a 12mm steel rail to flex it, just maybe I want it to flex instead of threaten to break stuff.

Despite your next sentence, I find that at least a little exciting! My coreXY project seems to be drifting towards being a laser engraver first. (That’s what happens when I buy a laser/pen control board which I’d have to retrofit into my Zen table, and “finished” projects don’t always get refit attention.)

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What’s that I hear about a “delta”. :grin:

I think that everything has been said already, but to sum up I’d say:

Extrusions:
Pro:
-Looks awesome
-Dead straight
-Relatively rigid
-Available everywhere (there are different standards though, with different dimensions)
-Can be made to very precise tolerances
-Wide range of compatible fittings
-Easy to work with
-Dissipates heat (can be useful sometimes)
-Can be machined by the seller to get some features (counterbore holes, threads, etc), which saves time later
-You can hide most or maybe all the wires inside the profiles depending on your build

Cons:
-Cost, obviously, both for the extrusions themselves and the fittings
-Can be very hard to get square/parallel
-Precise 90 cuts are extremely important, if you miss a cut then it will show later in the squareness of the rest of your build
-Be careful to select the correct type of fittings for the type of profile you own (different standards)

I’m a big fan of extrusions myself (shouldn’t be a big surprise if you already saw my garage), and I do think they are better than most other materials, especially for this kind of application.

They also do make a lot of sense when you try to sell kits, because you can just subcontract cutting, drilling and tapping to a supplier, ship the parts which really don’t take much space and be sure that the customer will be able to assemble the printer no matter what (provided you did your part at quality control, and provided said customer isn’t a moron, obviously).

They feel a bit less DIY and a bit more industrial to the customer though, it’s less cute.

So I’d say it mosly comes to personnal preference and budget. But if budget is not a problem then I believe the pro and cons list is undoubtly favoring the pros.

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So far still works for both systems.

Been putting a lot of time into this thing…It was supposed to be an alpha just to test some things… That said all the XY parts are in place and in a functional state, Z is done, all endstops are in place.

Last design challenge is the bed mounting (and any wire mount points). For the fastest alpha I am not trying to worry about a full non planer system (future), just something that can be adjusted a bit at three points. Probably a plate and springs. I have to look at marlin to see how it moves the three point bed and see what is important.

:crazy_face:

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