Anycubic Photon

[narrowminded]

Need video of these running behind your tiny mech.

If you only knew how I'm anticipating that day.   It's been years in the making. 

I still have to make the chassis that goes in this one.  The one you saw was really a power truck, 44" wheelbase to be used in an eight wheel loco, therefore no compensation for pickup assistance as I will use in a four wheel chassis.  The one I need for this one will be closer to an 80" wheelbase but the key components, drive train, wheels, and motor will be the same.  The compensation lets the one axle swing to follow track irregularities and will assure constant, perfect, flawless, pickup at all times and under all conditions.   I know that and hope the chassis does, too. 

There are many brands to choose from but very little in the way of good detail drawings.  One like this from Mancha are the basic type I'm looking to build.  There's some flexibility in the details as they were routinely customized per order and customer preferences and the general style was common across brands.

[ Guests cannot view attachments ]

[Chris333]

No excuses 

[ncbqguy]

With these units you could model the Chicago Tunnel Company...
The advantage is that you don't have to buld any rail road except a short s egment above ground near the Natural History Museum where the tracks came up to grade for an ash and cinder landfill dump!
Charlie Vlk

[chessie system fan]

Not that your loco has issues, but underbody gap fillers would be a good candidate to design.

I was thinking the same thing.  Once I figure out how I want it that's probably what I'll do.

[narrowminded]

No excuses 

Believe me when I say, I've done my homework on this, especially in making an Nn3 device this small that has a chance of running. And my goal is good operation first, while maintaining the general idea of a small mine loco to the best I can.

The locos you linked to are extra small (one to a few tons) and would not likely see the surface in coal operations as they would be used underground to gather cars from different rooms.  Even vertical hoist mines used them but always underground, hauling to the hoist shaft.  In a small, several man hard rock mine out west you might see one above ground but only pulling a few cars, true to the size of the operation, and most likely purchased used.  They were also quite often cobbled together from all sorts of parts that could be shoehorned together, as most of their equipment might be.  Today you can see some used in hauling coal mine tourist trains which doesn't need the tonnage but that wouldn't be so prototype.

That brief description leads to this.  I'm making a larger tonnage locomotive just so it's physically larger in scale because, even at the larger locomotive size, it's STILL smaller than ANYTHING I've ever seen that pretended to run or pretended to run with decent control and scale speed, and still maintains some fidelity to the prototypes (chassis about 1", o'all length about 1 1/8", o'all height about 7/16").  And the next thing is weight to assure some chance at performance.  To that end, this is already as dense with metal as it can be and just by the limitations of physics it can't be much smaller without totally losing any chance at reliable running.  Next, the smaller locos would be very common but common underground, never seeing the light of day in coal operations.  The larger size loco is what might be seen above ground in a slope mine.  Also, trolley types would be most common above ground but I'll need the height of a battery unit for weight and scale integrity.  Not unheard of but not as common.  Now, if I scale this up to HO, well the possibilities become endless.   And I plan to do that some day.

The next thing you'll see is the extremely short wheelbase with a HUGE overhang out towards the coupler ends.  That's trouble navigating trains through turns, especially turns that are tight radius.  By building the longer wheelbase style, even stretching that a little more than scale, cheating it but not ever getting close to something operationally ideal, I will attempt to get the best chance at performance while maintaining some fidelity to the prototypes, even if just by style.  We are routinely using tighter than prototype radius turns in all scales and this will be no different.  I can build the prototype dimensions in this regard and maybe I will some day but the performance on turns will be severely effected. 

These are some of the considerations that are driving my decisions.  Look at the sizes you linked, 1-5 tons(?), and then the one I linked, 15 to 18 tons.  That's where I'll need to be if there's a chance in Nn3.  My testing and parts development this far with these and more considerations says there is.   Wish me luck!

[narrowminded]

With these units you could model the Chicago Tunnel Company...
The advantage is that you don't have to buld any rail road except a short s egment above ground near the Natural History Museum where the tracks came up to grade for an ash and cinder landfill dump!
Charlie Vlk

Any quick links?  I've already got some projects in the pipeline for small(ish) locos that can use really miniature power trucks so maybe that should be another.  Or is it a battery mine style?  That was actually done in some ash handling applications.  I've seen some pictures of, I believe, a Jeffrey used like this but it also had a small cab added over the operator.  Weird looking thing.

[Chris333]

You could scale one of those up to get the size and wheelbase you need.

[Mark W]

@narrowminded this is awesome!  Really think it deserves it's own progress thread so the discussion doesn't get lost in here. 



I'm on my 6th print, 3rd different model in Anycubic White, using the same settings as Gray and getting identical results.

[u18b]

I've been working towards this moment for fifteen years.  Way back I tried modifying stock fuel tanks, only to find that they all have an incorrect profile or were too much work to correct.  I next tried scratch building, with mixed success.  But now...



Everything is just quickly test fitted.  And I still need to design a few little details.

Aaron, I love it.
Great job.

And he isn't kidding.   He's been thinking/talking/working on this idea for 15 years.
IIRC,  he acquired an Atlas SD50 and couldn't stand the look under the walkway.
I think he was 15.

[narrowminded]

@narrowminded this is awesome!  Really think it deserves it's own progress thread so the discussion doesn't get lost in here. 

I'm on my 6th print, 3rd different model in Anycubic White, using the same settings as Gray and getting identical results.

Thanks, Mark.   If there's anything to it, it's largely your fault.  Thanks.

I guess if I was to start a new topic it should be in the scratch building thread.   And I guess these things do clobber up a thread with this intent. 

Thanks for the info on the white.  The other night I tried lowering the exposure time on the gray just to see what it did to the final dimensions.  It was on the couplings which were adjusted and printing fine so I used them as my guinea pig.  I went from the recommended 18 seconds normal to 15.  They all printed fine and were usable but they came out very mushy/ rubbery.  I decided to cure them for a short time before to clean the holes out with the drill because they were so rubbery I feared I would distort them while handling or break the hole wall through while drilling it.  It all worked and when done, the measurement was basically no different, if anything a tenth or two, so there was nothing to be gained by this.  It was still educational.

What I am starting to see with some predictability is that there is a dimension error when opposing faces wrap about each other very closely.  The inside of that coupler is the example this time and seems to be the same in other areas, like the tapered cone inside axle pockets.  The resin must reflect the light and those faces must be close enough to see some of it.  The error seems to be about .003".  I edited this because the error was .003" but I moved it .005" for the correction plus an extra .002" for additional clearance.  At least that's the correction I've used and each subsequent print repeated the correction perfectly, making good parts.  The reduced cure time, at least that similar and required to print at all, didn't seem to make a measurable difference.  Maybe a little but a very little, hard to measure assuredly. 

And forget small holes, like .5mm +/- (for you, Mark) as the resin is just too viscous to cooperate in a hole that small.  I am still drawing them in place and that way, they serve as a perfect guide to run a drill through, nice and straight in just a pin vise, and as a result, very much on size.  I may even start drawing those kinds of small holes at .010" (.26mm)  larger than desired just to have less to clean and more assured of the good guide.  Not a big deal either way.

I'll be monitoring this as I go and will report any more observations.  Have you any to report?  And have you tried anybody's black resin?

[Mark W]

And forget small holes, like .5mm +/- (for you, Mark) as the resin is just too viscous to cooperate in a hole that small.  I am still drawing them in place and that way, they serve as a perfect guide to run a drill through, nice and straight in just a pin vise, and as a result, very much on size.  I may even start drawing those kinds of small holes at .010" (.26mm)  larger than desired just to have less to clean and more assured of the good guide.  Not a big deal either way.

I'll be monitoring this as I go and will report any more observations.  Have you any to report?  And have you tried anybody's black resin?

My Photon has been going almost non-stop building up inventory.  I'd like to take some time to experiment and really hone the settings, but I think I'll wait until I pick up a second printer.  Anycubic also states the Photon X will be out later this year too. 
Do I wait?     Do I not?   


https://i.imgur.com/sTVZbQP.jpg



https://i.imgur.com/PKEf11p.jpg


I feel like the white is just slightly less viscous than the gray, which is noticeably less viscous than the transparent green was. 
Actually, now that I think about it, I just printed an N scale Fire Hydrant with a .6mm hole to accept the blunt end of a push-pin.  That hole printed well (about .4mm opening). 

I also read an article (which I can no longer find) about print temperature.  The article didn't mention affects on details, but it did conclude that heating the resin allows for faster curing time, and there was no measurable difference in resulting print strength.  I might hypothesize that heating the resin does also improve detail, as it allows resin to drain away quicker.  Imagine a drop of resin trapped in a hole.  As each layer is exposed, that same drop is catching the light bleed, so it eventually cures itself.   However if that drop drained away and a different drop replaced it each time, the light bleed would be irrelevant. 

[narrowminded]

That's pretty cool, Mark.  It sounds like you are close in your experience with the holes.  I'm getting a hole but in those small sizes it's measurably less than intended. (.018" or .46mm).   I may review that and finalize the whole thing.  I really want to get some real world testing on the whole thing though, loco and all.  Have to get at that.

I see you are selling your parts on the platform in kit form.  I have considered making some for sale but was considering RTR.  Maybe that should be an option rather than the standard approach.  I also feel that I really need to get the loco going and make that available so a customer might have a full running train/ scene to utilize the cars.  And I'm not even sure that the interest I have in this would be shared by enough folks to even bother.  I am reaching a point of decision, though.

[Mark W]

https://i.imgur.com/sTVZbQP.jpg

Rumor mill now says  the Photon X is due in March!

Here is a photo.  Visible differences, there are now two rails for the z axis.  No more wobble. 
In the back, there are two circulation fans with some type of pre-filter.  The original photon has one fan that pushes air through an activated carbon filter hidden inside the unit.  If the filters are now accessible, changing them is a whole lot easier.

The key point for me will be whether or not the LCD is 4K rather than 2K.  That's still unconfirmed. 


https://i.imgur.com/0wMh3si.jpg

[narrowminded]

Rumor mill now says  the Photon X is due in March!

The key point for me will be whether or not the LCD is 4K rather than 2K.  That's still unconfirmed. 

Agreed.   Never too many little light thingies.

I'm not sure that the Z axis is an issue mechanically but I have also printed everything in a balanced load around center.  That may not be necessary either but in choosing a placement, why not balanced?  Then again, I may not have experienced the issue because I have always been able to balance the load.  Some shapes that consume the build area dimensions may be inherently off balance and maybe then, a problem surfaces.  Anyway, with machine tools, rigidity never hurts.

[AlwaysSolutions]

I've not personally had a problem with z wobble but I've heard of others having it.  Looks like the case will be injected molded plastic - I kind of like the solid feel of a metal unit but if they're to keep costs down after adding those rails I suppose I can see the need for it.  What I'd like to see in the next version is an upgrade to that touch screen interface so I can actually read what it's saying...elapsed time, time left in particular.

Mike