The Ship Model Forum

Thank you Pascal!

I attribute most of the issues to my fatally slow and unreliable internet connection. Perhaps the Elon Musk Starlink might be reasonable, good thing for Ukraine. Yes I need the latest update for a recent printer. I'm trying both MAC and Win as I have both, the MAC is a laptop but what I do most of my communications and photo work on.

Being a pilot I am working by trial and "Air".

Cheers: Tom

Gentlemen,

As promised, I'm keeping a close watch on all of this....

Up to this time, I've not had an issue downloading Chitu updates....but, there's ALWAYs a first time for everything.

Pascal/Tom - glad there was a work around available.

Hank

_________________
HMS III
Mocksville, NC
BB62 vet 68-69

Builder's yard:
USS STODDARD (DD-566) 66-68 1:144, Various Lg Scale FC Directors
Finished:
USS NEW JERSEY (BB-62) 67-69 1:200
USN Sloop/Ship PEACOCK (1813) 1:48
ROYAL CAROLINE (1748) 1:47
AVS (1768) 1:48

Hank:

I think I have to slim up the light weight supports a bit and thin my rafts down. Removing the myriad of supports in awkward place on your (superb) twin 3" 50 mount is very tedious. I can see a point for printing the barrels and receivers separate from the chassis.

Cheers: Tom

Tom,

The versions of Chitubox I am using didn't know anything about my printer. But the Photon Workshop that came with the printer did, and it had all the settings for the printer. So I just copied the settings into Chitubox and everything worked fine. Then I saved the configuration so it could be loaded again if I need to (I haven't).

Phil

_________________
A collision at sea will ruin your entire day. Aristotle

I just received yesterday the new Photon Ultra of Anycubic, there is no LCD screen:

https://www.kickstarter.com/projects/an ... ultra/faqs

This printer is very accurate. I will use it for small parts:

The same file, same resin: Mono X versus Photon Ultra. 50 microns both.

You can see that the pieces are printed thinner due to the lesser diffusion of UV in the resin, cause the beam i think..
It is likely that the dimensions are close to the dimensions of the design. I need to do tests on parts that penetrate.

I will have to take this into account in my design dimensions. Because it is very thin and fragile.

Look at the size of the tubes of the vertical ladder.

Mono X to the left



Photon Ultra:


Mono X:

_________________
Pascal

•Battleship Bretagne 3D: https://vu.fr/FvCY
•SS Delphine 3D: https://vu.fr/NeuO
•SS Nomadic 3D: https://vu.fr/tAyL
•USS Nokomis 3D: https://vu.fr/kntC
•USS Pamanset 3D: https://vu.fr/jXGQ

Pascal,

Wow!! Quite a comparison of the printing abilities of newer/older tech. But, I guess that's the name of the game - nothing ever remains the same, esp. in this arena. Thanks for posting those neat photos!

Hank

_________________
HMS III
Mocksville, NC
BB62 vet 68-69

Builder's yard:
USS STODDARD (DD-566) 66-68 1:144, Various Lg Scale FC Directors
Finished:
USS NEW JERSEY (BB-62) 67-69 1:200
USN Sloop/Ship PEACOCK (1813) 1:48
ROYAL CAROLINE (1748) 1:47
AVS (1768) 1:48

Yes, the better is the enemy of the good ... looking much better indeed. This make me and my watchmaking equipment looking grossly inandequate

Still, I am not so impressed by how these horizontal rails come out. Making them in wire would be better, but putting the holes into the stanchions would be a challenge, I agree.

_________________
Eberhard

Former chairman Arbeitskreis historischer Schiffbau e.V. (German Association for Shipbuilding History)

--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

Every resin and printer has divergent working parameters. As such I am having some teething issues moving to a new printer. So I will follow Phil's method of transferring some parameters. The Mono X 6K advertises a new material on the platen to increase adhesion. Yes it does, such that the objects stuck so firmly to the platen that chunks of the material came off with the objects. Fortunately I was able to completely remove this coating and am not back to bare aluminum. This may take some adjustment to work out! At least time wounds all heals and everything comes out in the end?

As to the wavy rails? My experience with my Rapid Black is they come out very well, after they dry fully. A vertical ladder printed for example, as I have said many times, has all the rigidity and a resemblance to cooked spaghetti till it tightens up after drying fully.

Cheers: Tom

For the railing, the design is not intended for this printer (Ultra).

On my drawing the bar is not glued to the wall, but with the Mono X the bar is glued to the wall during printing because of the UV diffusion. With the Ultra the bar is so thin that it is not glued to the wall, which leads to a lack of support and therefore the waviness. The design needs to be revised specifically for this new printer.

Monon X 4K:

Click to enlarge.

1/100 slicing:



1/350 slicing

_________________
Pascal

•Battleship Bretagne 3D: https://vu.fr/FvCY
•SS Delphine 3D: https://vu.fr/NeuO
•SS Nomadic 3D: https://vu.fr/tAyL
•USS Nokomis 3D: https://vu.fr/kntC
•USS Pamanset 3D: https://vu.fr/jXGQ

I have been printing some older items as workup items to get the new printer tuned up. As Pascal notes, perhaps some design parameter changes necessary. One of my more favorite items were the 5" twin mounts that I printed for Alaska and Missouri to replace ones Had resin cast and bought from MM. There are some very find hand rails and grab irons which print just fine but are so thin and fragile so as to require extreme care in handling. With the new printer these print thinner, more to the design, some may need beefing up.

Phil has mentioned the effect of the fluid dynamics, my initial 5" mount prints effort had wonderful detail, but the bottom edge curling up problems. An orientation change may help here? Maybe a settings change.

The adventure continues.

Tom

I think I am getting there, slowly.

This is my 1:192 Twin 5"38 mount which I had printed for AK and MO. I am very happy with the small hand and foot rails, even all the rungs on the aft of the mount printed fine. The barrels are a separate print and slip in through the hollow barbette and can be adjusted for elevation and are on a common sleeve. To eliminate issues with bottom drooping I inclined the whole unit at 15 degrees along the barrel axis.



The grab irons are tres dinkydau dinky at this scale.

Tom

Post Script, printed in Goopy Grey as opposed to the rapid black, photo in the "raw", no primer.

Further Post script for Pascal: I had success in sweeping out the bubbles, but had previous experience applying reflective mylar to a friends balcony windows in Novosibirsk. But yes some learning curve involved!

Good to know!

Nice print.

You can reduce the UV Power on Mono X only by the screen of the printer. It saves the UV lamps and the parts are more accurate.

_________________
Pascal

•Battleship Bretagne 3D: https://vu.fr/FvCY
•SS Delphine 3D: https://vu.fr/NeuO
•SS Nomadic 3D: https://vu.fr/tAyL
•USS Nokomis 3D: https://vu.fr/kntC
•USS Pamanset 3D: https://vu.fr/jXGQ

Tom,

Very nice print of the 5"/38 mount!!

Here's a question for Pascal, Tom, & Phil - what curing times do you use for your parts? I have one of those rectangular UV lamps with the multi-cube lights but still have no set time for curing - any ideas/thoughts, etc.?

Thanks,

Hank

_________________
HMS III
Mocksville, NC
BB62 vet 68-69

Builder's yard:
USS STODDARD (DD-566) 66-68 1:144, Various Lg Scale FC Directors
Finished:
USS NEW JERSEY (BB-62) 67-69 1:200
USN Sloop/Ship PEACOCK (1813) 1:48
ROYAL CAROLINE (1748) 1:47
AVS (1768) 1:48

3" 50 printed today, used on various smaller vessels, LST's, AO, DMS, DE's and whatnot allowing some AA capability and replacing the single purpose 4" on the old 4 pipers. In 1:120 scale but I have also printed some in 1:144, which Hank has also used on his T-3 project. This could be printed as one piece but sometimes separately allows the barrel to be easily printed at an angle whereas the chassis prints fine horizontally.

Something weird as these came out as the only ones out of three, which ended up as blobs in the tank. The raft showed some leaving suggesting that there was a problem with the base layers?

Cheers: Tom

Hank,

Good question! I have a 20 Watt UV light like this:



It has the light powered turntable to rotate the parts during exposure. I mounted it in a hole in the side of a cardboard box and lined the box with crumpled aluminum foil to get good light scattering.

Some sites say to expose for very short periods - a minute or less - for small parts and up to 5 minutes for "large" parts. However, like a lot of what you see on the Internet, they never say what light intensity they use. And I have never seen any data on the proper exposure times for resins on manufacturer's web sites.

I have been guessing at exposure time to cure the printed parts. I read that overexposed parts have crusty white areas, and I have seen this happen on some Anycubic Basic Grey parts that were exposed for more than 10 minutes. For very thin and small parts I have been exposing for a total exposure time of a minute or two. Larger (1" to 2") parts have been exposed up to 6-9 minutes total exposure times without getting the white "burn."

I typically expose parts in two to three separate short intervals, rotating the parts between burns to get a more even exposure. So a 9 minute exposure is done with three separate 3 minute exposures.

I am guessing because the manufacturer's don't give a clue as to shat light intensity (lumens) and exposure times are needed to properly cure the parts. The Anycubic Basic Grey cures to a firm surface in just a few minutes, but the Pfrozen Fast Black seems to be a bit sticky with the same cure times.

Tom has mentioned that he allows the Fast Black parts "dry" for a while (unspecified time) after printing, and I think he means before curing. This may be a consideration for water washable resins.

Like I said, I am just guessing.

Phil

_________________
A collision at sea will ruin your entire day. Aristotle

Phil:

Yes for the Rapid Black I let it dry till it assumes a flat matte but smooth non specular surface. For that resin I find a first alcohol was before several water baths useful. If there are rails etc, let dry till these tighten up. Stickiness or a glossy surface suggests an insufficient wash.

Tom

Tom,

Your "leaving" in the tank - was this due to the base layers becoming unattached from the print platform, or was it the printed part separated from the supports?

Here is how I think I understand the print failures I have had.

The adhesion force for the base layers has to be greater than the adhesion force for the printed part to the FEP film at the bottom of the resin tank. These forces are dependent upon the surface area on the platform and FEP film. And the relative forces probably vary with different types of resins. The surface area for the base layers is the same for the platform and film, and I haven't had the base layers separate from the print platform, so the attachment to the platform is stronger than the attachment to the FEP film.

But this will depend upon how clean the print platform is. If the surface is dirty, oily, has fingerprints, etc. the resin may not adhere strongly. I have been scrubbing the platform with alcohol and/or water after each print job to be sure it is clean.

The same is true for the supports between the base layers and the printed part - the same cross section area where the supports attach to the base layers as the cross section on the FEP film. But Chitubox defaults to a conical end to the supports where they attach to the printed part, with a much smaller cross section at the attachment point to the part. So the base layers and supports have a larger area/stronger attachment to the print platform than the support attachments to the printed part. These attachment points between the supports and part are the weak link. Chitubox allows you to reduce the attachment point diameter. This leaves smaller "pimples" where the support attaches to the part but also weakens the attachment.

If the cross section of the part being printed is a lot larger than the cross section area of the support attachment points, the force needed to separate the part from the FEP film may be greater than the attachments can take, and the printed part breaks away and remains as a blob on the FEP film. Been there, done that!

The separation force is dependent upon the Lift Speed. So a part may print OK with a slow lift speed but fail with a faster lift speed. Increasing the number of supports (total cross section area of the support attachment to the part) should allow a faster lift speed.

However, if the cross section area of the printed part is greater than the cross section area of the base layers/raft on the print platform, the separation force may become greater than the attachment strength of the base layers to the print platform, and the whole thing could come loose from the platform and remain stuck to the FEP film. Making large parts hollow will reduce the cross section area on the FEP film and reduce the force necessary to separate the printed part from the film.

Reducing the wall thickness of hollow parts will further reduce the force necessary to separate the print from the FEP film. I have been using 3mm and 2 mm wall thickness in Chitubox, but I have seen 1.5 mm recommended on some web sites. I suppose this might also depend upon the type of resin, but I have seen nothing written about this.

It was all so simple when I made my first prints a few months ago, but now I am having trouble wrapping my head around all of the variables!

Phil

_________________
A collision at sea will ruin your entire day. Aristotle

Phil,

Regarding the "Curing" process & your reply above:

I have the same lamp/turntable setup as you do - however, they are simply set up in available space w/o any special box or designated area to operate. As such, I've been curing generally for anywhere from 15 minutes to a couple hours depending on how many parts are on the turntable. Again, you are quite correct in mentioning the lack of any guidance on this process from the resin mfgrs to the printer mfgrs.

Several years ago (2015-2019) when I was purchasing the Shapeways 3D printed products (generally white or frosted parts) I set them out in direct sunlight for usually 1/2 hour or so from basic guidance from whomever I purchased those parts from as none of them were cured at purchase. The SLA resins are a different type of material so obviously require a different approach to this process.

Quite recently I've been drying my parts (either Rapid Black, Matte/Model Gray resin) under a small fan usually overnight and then if any of what Tom describes as the shiny surface remains, take a pointed swab and clean off that surface film as much as possible. Then, put under the lamp and cure. For the thicker, larger hull section parts I've been curing for around 1/2 to 3/4 hour and then readjust and repeat.

At this point I've only been washing my parts in the 91% alcohol and no water bath. I may add a 2nd wash in fresh water just to see if this has any visible effect on any remaining surface resin film, etc. and then do the drying. I'll see if the shorter cure times as you mention seem to work. I've not seen any of the "crystalization" as you describe with any of these resins.

Thanks for the input, always helpful!

Hank

_________________
HMS III
Mocksville, NC
BB62 vet 68-69

Builder's yard:
USS STODDARD (DD-566) 66-68 1:144, Various Lg Scale FC Directors
Finished:
USS NEW JERSEY (BB-62) 67-69 1:200
USN Sloop/Ship PEACOCK (1813) 1:48
ROYAL CAROLINE (1748) 1:47
AVS (1768) 1:48

Wonderful discusions, thank you all for that.

Sometimes I have the feeling, the possible possibilities are sometimes making blind a bit.

There are marvellous examples of printed gems here to be found. Congratulstions. But I often wonder why it is so often tried to print all parts in one go. It IS possible to incorporate all the details in one print, but is it wise? Let me take icemans wonderful part. (Excusez moi Messieur!)

The bottom part is wonderful, the steering booth also, the details are perfect. But still on the roof one sees the layers of the printer. Deviding the whole into a lower deckshouse, the roof, the booth and the other details it would make things easier to sand, to smooth, to paint. Every part could get an optimised direction in the print, the roof possibly vertical. And afterwards just do it the oldfashind modelmakers way, glue them together and give the final color touches.

I use this technik often for my parts and it helps a lot minimizing the steps that still are appearend. Also I usually can avoid to shift the parts to odd angles, as I use vertical and horizontal planes as they come. And it makes the supports also easier, if each part has its optimized orientation.







All the best, DAniel

_________________
To Victory and beyond ...
viewtopic.php?f=59&t=99050&start=60

See also our german forum for the age of Sail and History:
http://www.segelschiffsmodellbau.com

For a couple of my models I modeled the commonly employed Bofors, twins and quads. Some were successfully printed as a single unit and some assembled with separate barrel units and shields. They can be printed OK as a single unit, however placement and more importantly, removal of supports can be much easier with the separate parts. In the manner of shields, the Quad Bofors again expedited support removal and painting of these very complex units with the wrap around shields separate. However assembly can be a PITA, so each method will have it's optimal application. Very small parts cane printed, but the smaller the parts the more problematical assembly which has mechanical and aesthetic issues. The very complex D-7 Dozer that I did was printed as one piece, assembly would not have yielded as accurate a piece.

Post script for Phil: Drying, it really shrinks and straightens those rails, such as on your MK 37 if they fully dry. This can take quite a while, currently my indoor humidity is 3% and It took an hour sitting over the warm air register to finally get them to straighten fully! Once they get cured, any waviness likely to be cast in stone.

Cheers: Tom