Marc's Elegoo Saturn Workbench

Yesterday a box arrived at the house with my long awaited Elegoo Saturn 3D printer. It's been a long time since June when I ordered it. I have unboxed it but I'm not allowed to play with my new toy until Monday. There was a rumour going round that it was going to come with 500ml of resin but that wasn't in the box. So my first job is to order some resin. which is a job for this afternoon.
Once its fully set up and operational I will post some pictures.

Since I ordered it I have been drawing out wagons and parts to print so I'm not going to be idle for the next few weeks. At the last count there were over 20 new items just waiting to go.

Marc

 

Marc, I’ll be watching this with interest. Looking forward to my own Saturn in a couple of months.

 

I think the difference between the two is basically the print area. As I do 7mm I went for the larger machine. I think its the same DPT. The step value is the same. The plan is to replace our cast resin with the print as it more environmentally friendly

Marc

 

First test print was done this morning. Mixed results but I have been told that the main problems were caused by not tilting the model. Resin printers don't do flat, so I have been told.So I'm going to have another go tomorrow and see what happens. the parts that did print were not bad for detail but that is overshadowed by the other bits that didn't print properly.

Marc

 

the dpi for the Mars is 0.047 for the 2K screen (2560x1440) with a size of 115x65 and 150high; and the Saturn is 0.05 for the 4K screen (3840x2400) with a size of 192x120 and 200high. Z axis on both is 0.01. All mm. Cheers Ian

 

I'm new to resin 3D printing as well, having recently bought an Elegoo Mars. I've only printed one part successfully in the flat, but that was OK and printed well. Everything else does need to be inclined and raised off the bed by around 3mm to allow space for the base plate and supports. I've probably used too many supports on some parts, but have had issues with the part detaching from the supports.

I have a few settings that work for me, having tried a few others, like some of the pre-sets for my machine, which did not work. I've now reverted to the original settings used and these seem to be working ok.

Plenty of experimentation and patience required, along with experience before can be confident that I understand enough, but that is part of the fun. I always expected a steep learning curve, and much steeper than when I bought my filament printer, which is still going strong and producing good results.

 

Print 3 was not really any better than print 2 if anything it was a bit worse. I inclined the model at 30 degs bow up and the other one I gave a 30 degs list both had a slice at 0.03. Not sure what is going on. These models printed with shapeways and I'materialise.
The were both missing detail on the edge closet to the build plate and they both had a line across about halfway up.




I'm thinking of swapping the detail quality for completeness on the next run. moving the slice to 0.5 and cranking the angle up to 50 degs to see what happens. If it prints the whole model but the quality of finish is not good then at least that's only one issue to deal with not two. And then i can reduce the slice thickness.

Marc

 

These should have been attached to the last post.
Marc

 

Marc,

If you do another print, can you take a picture of the body still on its supports, which could give a better picture of what's going on.

Jim.

 

will do the just snapped off as I took them off the plate. Do you think lifting the model off the plate by a few mill might be useful as its always the bit closest to the plate that is missing or damaged?

Marc

 

Marc,

I think that the problems you are seeing are caused by supports breaking away from the model and allowing it to "wave about in the breeze". There is a fair amount of adhesion of the resin to the FEP sheet when it has been exposed and if this is too much for the supports when the plate is lifted between exposures, then they can break away from the part. When a print has finished and you can see obvious problems while it is still on the plate, then have a look at the supports under the problem area to see if they are still connected to the part, or whether they have broken away. If they have broken away then you have to place more supports in the area, or re-orientate your part to decrease the area in contact with the FEP at any time.

I use Chitubox as my slicer and that allows me to play through every level of the slice in quick time to see each level. That can show you where you might have one or more instances where there is a large area in contact with the FEP. TGhen you might need to re-orientate to reduce the area.

I've been having similar problems to you with some of the work I've been doing recently - but with much smaller models. In my case I was trying to keep the number of supports as low as possible to avoid disfiguration by the supports on the finished model. Some of my parts would be mis=shapen or even had completely fallen off the supports into the resin bath during printing. I had to do a fair bit of re-orientation and adjustment of support placement to get success.

BT W, if you do lose parts off the plate during printing then they will most likely be stuck to the FEP and you have to drain your resin tank and get rid of any bits and pieces. If you don't you run the rick of damaging your LED screen with succeeding prints. It's a bit of a chore, filtering the resin through a fine filter to catch any loose bits and scraping off (carefully) any bits stuck to the FEP.

Jim.

 

I ran the took model through the printer this afternoon. Perfect. As these were flat to the plate in going to run a GPV chassis through tomorrow in the same way and see what happens.
Marc

 

I'm using chitubox and I did use the automatic supports. I printed a chassis for a small NER gunpowder van this afternoon. Some of the supports came away from the plate which caused some damage but usable for me.

Apart from the slight damage it was the correct shape. It was 6.5mm away from the plate and I increased the diameter of supports at 1mm and an angle of 45deg.

If the supports are coming away from the plate should I be increasing the initial exposure time?

Marc

 

Marc,

It might be worth checking that your build plate is lined up properly. It could be that it is very slightly high in the area where the supports are coming away. I'm not sure how you do that on the Elegoo machine but it is usually an operation which can be done in a few minutes.

Jim.

 

Marc, it would be helpful to see a failed print before support removal.

Supports tend to fail in one of two areas: the raft not sticking to the build plate or the supports themselves breaking. When printing takes place there is a tug of war going on between the build plate and the fep with the supports in the middle. All being well the raft adhering to the build plate and the support strength overcome the effort needed to peel the print off of the FEP.

It sounds as if the raft is sticking to the build plate OK so it is unlikely to be levelling (but it never harms to check). Support failure can occur for a number of reasons: too few supports, too thin supports, insufficient layer exposure.

Chitubox does feature an autosupport feature which to be honest leaves a lot to be desired. You can select from light/medium/heavy supports and control the support density but it is probably easier to add the supports manually. First determine if the model needs to be tilted to reduce any cross section presented during the printing process. For example a wagon parallel to the build plate will have a very large cross section when the floor prints.

I tend to use medium supports and lots of them. Too large a gap between supports allows the print to deform. I use the light supports for fine detail or where I think there is a good liklihood of damage on removing them.

Hope that helps.

 

Success I have managed to print a North British 1 plank and a chassis for a North Eastern gunpowder van with nothing going wrong.
I increased the diameter of the supports to 1mm, 45s for the first exposure then 2s after that, a 45deg tilt and 0.03mm slices.
I will post some pics in the morning.
Marc

 

So things are going well I have successfully printed the first production models of the M&GN 3 plank, the Maryport and Carlisle 3 plank, NER gunpowder van chassis, Midland Gunpowder van chassis and Mid-Wales/Cambrian brake van.

The photos are a bit poor as I took them on my phone.

Marc

 

I'm struggling with cleaning up the water soluble resin. It keeps sticking it's to the sink. It comes of the prints ok but not the sink and as you all can probably guess SWMBO is not to happy with this any one else solved this problem. we have tried very hot soapy water, kitchen cleaner even a brillo pad. Any suggestions welcome before SWIMBO makes me sell my new toy.

Marc

 

Polythene washing up bowl?

if it’s anything like the PVA that the extruded 3DP machines use, it’s not very nice, and it is very sticky, but a brush and hot water shifts it eventually.

Hth
Simon