Hobbyist Forums banner

101 - 120 of 160 Posts

·
Registered
Joined
·
118 Posts
Discussion Starter #101
Printing out what will be a foot bridge from the plateau area to the adjacent peak:

310594


The peak will have an OP on it, although I haven’t decided how that will look.

Couple possibilities:

310595


310596


310597


I'm leaning towards the last pic. Seems looking modern enough yet still has an enclosure so "observers" have a place to go to get out of the elements as well as keep things like radios and electronic safe.
 

·
Registered
Joined
·
118 Posts
Discussion Starter #103
Good choice. Size wise though will it look right in relation to the rest of the layout?
Yup.

I can scale it to whatever size I want in Cura. That watch tower is supposed to print at 16" tall. I'll just scale it down, watching to not loose too much detail in the process.

I have a couple other 3d graphics programs that I can use to alter it if need be.

Scaling is the most useful tool though. I can take whatever model I find and scale it down (or up) to the size I need.

For example: the RC boys are big into making 3d "shell" bodies. Thingiverse is full of them. Cars, trucks, you name it. All I have to do is download the STL files, scale them to HO and I have a ready made HO slot car body. If the wheels or width doesn't fall out to the right size, Cura will even let you change scale in one axis only. You just have to be careful not to distort the model so much that it doesn't look like what you started with...
 

·
Registered
Joined
·
118 Posts
Discussion Starter #104 (Edited)
Foot bridge going in:

310611

310612


Not too shabby!

It may look like its a little “tall”, but I wanted it high enough that “big rigs” would pass underneath it. At that height, the trailers just clear.

The bridge itself is actually a “train trestle” bridge, originally made for a scale train setup. It was actually quite large to start with, but I just scaled it down to foot bridge size and I think it turned out pretty good. I wanted a bridge structure that looked solid and permanent, and this one fits the bill nicely!

I still have to build up a transition on either side and make some steps up on each side, but its coming together nicely!

:)
 

·
Premium Member
Joined
·
9,016 Posts
It looks great congrats. 👍
 

·
Registered
Joined
·
118 Posts
Discussion Starter #106
"Steps" made for the bridge and starting to build the OP:

310657


310658


Currently printing out the platform railings and another two "leg" stand sections. I think I only need one more, but printing two just in case.

:)
 

·
Registered
Joined
·
118 Posts
Discussion Starter #109
Printed off a second tower trellis:

310704


310705


I think that's tall enough. I feel like another section will make it look too tall and out of scale. You can also see I've started filling in the space under the footbridge and steps.

Next:

310706


No, it's not the starship enterprise! LOL!

It's a rescue helo and landing pad. Only 21 hours to go.......:rolleyes:
 

·
Registered
Joined
·
118 Posts
Discussion Starter #111 (Edited)
Chopper and pad:

310733


That's just the rough print. Still needs filling and smoothing.The hole in the tail is where the tail rotor will go (have to print it first). I may have gotten the scale a little too small, but I'm not going to spend another couple days reprinting it. This is close enough!

;)

While the printer was running, I started finalizing the wiring:

310732


Still a long way to go, but I like the way it's shaping up so far!

:)
 

·
Premium Member
Joined
·
2,283 Posts
Very interesting 3d printing, what is your model of print & material extruding? Very interested in checking into 3d printing after seeing your excellent results. Keep posting you are making great progress & very interesting posts. One dedicated follower.
 

·
Registered
Joined
·
118 Posts
Discussion Starter #113 (Edited)
Very interesting 3d printing, what is your model of print & material extruding? Very interested in checking into 3d printing after seeing your excellent results. Keep posting you are making great progress & very interesting posts. One dedicated follower.
I use a Creality CR-10 V2, it's an FDM (Fused Deposition Modeling) printer. They range anywhere from a couple hundred to a grand or more. Mine is a bigger model (300x300x400 mm) and is higher up the price range. If you look it up online, you'll see it offered for around 499, but that's USD. I bought mine from a Cdn reseller, so it came out to closer to 800 Cdn, after taxes and shipping. But if you can make do with a smaller printer, you can get in somewhere around the 300-400 Cdn range.

I'm only using PLA right now (CR-10 will handle PLA/ABS/PETG/TPU), which is one of the easier filaments to print with. PLA breaks down in sunlight though (ie: goes brittle), so use printed stuff inside or at least paint it if exposed to sunlight.

There's also an SLA printer on the market, which essentially uses a big vat of resin. The printer "hardens" the resin layer by layer, which builds the model. Both FDm and SLA print n layers, just the process is different. My FDM printer has a spool of filament (just a roll of thermoplastic "thread") and it melts that and deposits it layer by layer to build up you item.

You can get better resolution (ie: brick walls, smaller parts, etc) with a resin printer, but they are also more expensive than an FDM printer. A 1kg spool of filament can be had for somewhere around 30 bucks (on sale), but I have no idea how much resin costs. I am under the impression that it costs more for resin than FDM, which makes sense to me because a gallon (approx 4 liters) of polyester resin for fiberglass is around 100-150 bucks a tin when I buy it from Napa for fiberglass work.

FDM isn't perfect though. It can be weak in thin parts (remember; it's just a bunch of hot plastic lines stuck together) and you can end up with random "blobs" and a rough surface that needs sanded and filled to be perfect. But for modeling, it works fine and is fairly economical for the home user. It is a pretty slow process though.

I bought the bigger printer so I can lay multiple items on the print bed and then just let it go for a couple days.

I bought mine from a place in Ontario called "mech solutions". They've been pretty good with after sales service also.

I probably would have spent much less if I had just gone out and ordered my track/model bits "pre-made", but then you have to settle for whats available and the scale that it comes in. I put in a little time and learned how to scale and alter models, so I can pretty much make whatever I want for my track.

You can also order 3d printed parts from many places, as long as you have the file to send to them. Those places have big "mega-buck" machines, so they can print much nicer finishes and in many different materials. But you end up paying pretty dearly for even small things. Something on the order of 20 bucks for an HO car body, but the body would be much stronger than an FDM print. You just have to make sure your file you send them is exactly what you want (ie: size, shape, wheel openings, body mounts, etc), or you just wasted 20 bucks on a desk ornament.

Not to mention, my FDM printer can be used for a lot more than just modeling/toys. Just the other day, I printed off new keyboard feet for my broken ones. There's no end to what you can make with it, as long as you understand the limitations of it and the strength limitations of the different materials.

Here's a good read on the basics:


:)
 

·
Registered
Joined
·
118 Posts
Discussion Starter #115 (Edited)
So, I don't want anyone to get the impression that "3D printing" is a walk in the park. Basically, I don't want someone spending hundreds of $$$, expecting to "go town" printing stuff based on my posts only to find out it's (sometimes, perhaps often) a bit of a PITA.

True, you can make some things you otherwise might not be able to buy, but it's not like setting up an inkjet printer, hitting "print" from the drop down menu and letting it go to it.

I struggled for nearly a month to get the bed leveling right. Bed leveling refers not to leveling the bed (at least not like you would with a spirit level), but making sure the bed is a certain distance away from the nozzle across it's entire travel. That's basically the thickness of a piece of paper (about 2 thou). I threw away a lot of plastic filament in that first month....

Compounding the issue is that the glass bed is not even across it's surface (most glass isn't) and the only adjustments you have is a screw jack at each corner. If your glass has a big low spot in the middle, you're going to have a nightmare of a time getting the nozzle clearance even across the whole plate and you usually end up with bed adhesion problems. Remember, we're talking about a 2 thou difference between success or failure! Get it wrong and either the brass nozzle crashes into the glass (and scratches it) or it extrudes plastic too high. Too high means it either makes a big squiggly ball of hot plastic or it starts printing and then the "ball" breaks loose from the hot nozzle and becomes a big mess somewhere else on your print. Worse case scenario is it "sort of" adheres to the bed and somewhere into the print it just breaks loose and all become a big hot mess. I had to buy a "BLTouch" sensor (the glowing red thing on the RH side of the print head) and set the offset super low before I was able to get good bed adhesion for printing.

A BLtouch is essentially a HALL effect sensor. It sticks out a probe and when the print head lowers enough to "pop" the probe back in, the firmware records the value and remembers how low the print head had to be before the sensor touched. Then, you have to determine the "offset" value you need in order to get the head the right height for printing. The sensor checks multiple points all across the bed (somewhere around 25-30 places) and applies the offset, in order to keep the print head "X" distance off the bed. This would be your 2 thou clearance. If one point is lower (or higher), the firmware lowers (or raises) the print head a little more in that spot, maintaining the print height from the bed, regardless of bed warp-age. You don't absolutely need one to 3D print, but for 50 bucks, it makes your life sooooo much easier.

But even when you get it all right, sometimes it will still mess up. Take the picture below for example:

310766


That's the grandstands printing out. If you look in the center, you can see the "steps" that are part of the stands. They're messed up, even though they started out fine. What happened is that the nozzle went by once and "nicked" a piece of one of the steps. Sometimes the plastic will expand or contract once extruded and if it's not adhered to the bed properly (or it's a small part with not much structure) the nozzle will knock it loose on the next pass. What happened on this print is the nozzle knocked one step loose. So it was standing a little proud next time the print head came by. This not only knocked it a little looser (including a couple other adjacent steps), it also made the next layer laid down not contact the existing print. This meant it just squirted out of the nozzle and turned into a squiggly ball of hot, almost melted plastic.

The problem with that is now the print head was dragging a squiggly ball with it and when it got to the next piece, you get a big blob of plastic on the print. If you look at the top center piece, you can see the blob down between the lines. Luckily, it doesn't matter in that spot because it will be buried down inside the finished piece. But it just as easily could have ruined that print as well.

So what I had to do to save the remaining pieces was take some scrap pieces and glue them down to the parts that were missing pieces. Remember: you have to try and do that while the printer is still running, without negatively affecting it's freedom of movement. Not an easy thing to do.

I also had to try and cut the blob off the other piece before the nozzle came around again.

The reason I had to add scrap was that if I couldn't get the extruded filament to adhere to something, it was just going to keep making a big hot ball of plastic every time it went by that spot. Obviously, that would ruin the entire print. You could get around that by printing one piece at a time, thus being able to stop the printer and chuck the messed up part away and start again. I didn't want to waste the time (or plastic) so I kept adding scrap until the filament was able to grab it when extruded and thus prevent that big ball of hot plastic from growing every time it went over that spot.

If all this isn't enough to deal with, a 3D printer goes through a heat cycle every time you turn it off/on, so things like the bed leveling will move slightly. The BLtouch sensor helps with that, but sooner or later you will have to go through the set up process all over again.

You also have to clean the print bed after every print. Spotlessly clean. I use Windex a couple times until I can't see anything on the surface and then hit it with 99% IPA to finish it. Then I use the most extreme hold hairspray I can find on the bed before a print (immediately before printing as the bed is heating). You don't want to spray the bed any significant time before printing, or it will just grab dust and dirt and ruin the bed adhesion. The hairspray helps stick the first few layers to the bed stronger than just the plain textured glass. Then it's sterile clean all over again before the next print...

3d printing isn't perfect, but if you are willing to put in the time to get it set up right and learn it's intricacies, it can be pretty awesome. But don't be fooled into thinking it's "easy".

And yes, it's probably as close as we have gotten yet to a Star Trek "replicator".....

;)
 

·
Premium Member
Joined
·
2,283 Posts
Thanks very much for all the info but not ready for a 3d printer yet & appreciate your printer expertise in producing your track details.
 

·
BANNED
Joined
·
8,125 Posts
how about a word regarding software and how to use it?
what background is required or what is the learning curve?
 

·
Registered
Joined
·
118 Posts
Discussion Starter #118 (Edited)
how about a word regarding software and how to use it?
what background is required or what is the learning curve?
Depends. If you just want to print an .stl file, you just need the included "slicer" software and then print.

It's called "slicer" software because it takes a 3D file and chops it up into 0.4 mm layers (can be thinner or thicker, depends on the size of your nozzle), which is how the printer creates the object: 0.4 mm at a pass. Sloooooowwwwwwww........

If you want to alter or create 3D files, it gets much more complicated (and expensive).

I use Ultimaker Cura for my slicing software. It's a free download from Ultimaker. Cura lets you resize things, but not a lot more than that. I use Cura because the slicer program that comes with my Creality printer is basically a "stripped down" Ultimaker Cura program.

If you want to create 3D objects, then you have to get into things like CAD software.

As to "background": I can't say. Everyone is different. I know guys who have been trained to work in CAD and still have a hard time producing things, while some guys just pick it up as a hobby and fly though it like they've been doing it their whole life.

Keep in mind I'm just a "hobbiest" at this as well. All I know is what I've learned on my own so far.

I kind of liken learning the slicer program as opposed to CAD as learning TIG as opposed to MIG. MIG has a fairly easy learning curve and it doesn't take long before you can run a decent bead. But with TIG you can buy the fanciest welder and you can run lots and lots of beads, but you need a couple years "hands on" practice before you're any good at it....
 

·
BANNED
Joined
·
8,125 Posts
thank you for the explanation.
I have been considering getting a resin printing 3D printer.
I just don't know if I am going to be able to create files for it to print from.
you seem to have found sources for the items you print?
or are you writing files yourself?
thank you for the advice and yes, liking what you are doing with both tracks.
 
101 - 120 of 160 Posts
Top