ROV parts

[DavidF]

been printing the parts for my ROV, here is the bucket for the excavating arm...
[img]http://i1102.photobucket.com/albums/g446/davidflowers1/utf-8BSU1BRzA1NzkuanBn.jpg[/img]

[Eaglezsoar]

That is going to be one big machine when it is completed. I do hope you are going to post pictures of the completed project.

[DavidF]

That is going to be one big machine when it is completed. I do hope you are going to post pictures of the completed project.

I sure will. Might be a long time to complete it though....That bucket chewed thru a whole 1kg spool of filament, 2 mm walls 20% infill .2mm layer and I slowed the print speed way way down to 20mm sec, 40 hours later and I have a very nice looking bucket that can take some abuse....

[DavidF]

ill start grouping the pics into this thread. The one should give you a good idea of the size of this project...
[img]http://i1102.photobucket.com/albums/g446/davidflowers1/utf-8BSU1BRzA1NzMuanBn.jpg[/img]
[img]http://i1102.photobucket.com/albums/g446/davidflowers1/utf-8BSU1BRzA1NzYuanBn.jpg[/img]
[img]http://i1102.photobucket.com/albums/g446/davidflowers1/IMAG0571.jpg[/img]

[Eaglezsoar]

Someone is going to be very happy when this is completed. From the size of the parts this is going to be huge.

[geneb]

David, I think that 20% infill may come back to bite you if the ROV reaches a depth that can exploit the air pockets.

g.

[DavidF]

Someone is going to be very happy when this is completed. From the size of the parts this is going to be huge.

Or someone is going to be very broke from all the filament LOL.... But now you can see clearly why I bought the rostock.....

[DavidF]

David, I think that 20% infill may come back to bite you if the ROV reaches a depth that can exploit the air pockets.

g.

No it wont... this rov is meant for shallow water, its going to be used in the surf to metal detect and dredge lost jewlry. I did the calcs awhile ago with help from and engineer and 60' is not an issue, but I doubt it will ever see that depth...

[geneb]

Ah, cool!



g.

[neurascenic]

David, is this the same as your avatar?

[DavidF]

David, is this the same as your avatar?

Yes, but I have redesigned a few things that aren't shown in the avitar. It will look similar but the manipulator has been replace with a suction dredge/separator module that isn't very appealing to look at...

[Eric]

You can always add weights if it turns out to be too buoyant or if the surf pushes it around too easily.

Looking forward to some real assembly pictures.

[Woolf]

respect, really nice design work and print.

[neurascenic]

David, is this the same as your avatar?

Yes, but I have redesigned a few things that aren't shown in the avitar. It will look similar but the manipulator has been replace with a suction dredge/separator module that isn't very appealing to look at...

The uglier the breed, the more I like 'em. (Full disclosure: probably because, I can't run with the beautiful people)


And! Damn cool!

[Captain Starfish]

David, I think that 20% infill may come back to bite you if the ROV reaches a depth that can exploit the air pockets.

g.

The prints are so porous that it doesn't matter, geneb - I've printed parts at 25% infill for my rebreather that I'm diving to 60m with no problems at all but these are structural parts, nothing involved in trying to keep gas and water separate yet until I get a way of holding a decent seal. Which I suspect will come down to using the print as a plug for a silicone mould for epoxy or polyester parts.

[Eaglezsoar]

David, I think that 20% infill may come back to bite you if the ROV reaches a depth that can exploit the air pockets.

g.

The prints are so porous that it doesn't matter, geneb - I've printed parts at 25% infill for my rebreather that I'm diving to 60m with no problems at all but these are structural parts, nothing involved in trying to keep gas and water separate yet until I get a way of holding a decent seal. Which I suspect will come down to using the print as a plug for a silicone mould for epoxy or polyester parts.

Could you just coat the part itself with a layer of epoxy to seal it? I know nothing about rebreathers but I have been wondering about this for awhile. It would seem that it
could work but I am looking to you for an answer because I really don't know if you or anyone has tried it.

[Captain Starfish]

I've had extremely limited success with vapour baths for ABS to get a 1 bar (14.5 or so PSI) seal but it takes a fair bit of mucking around. Even the "soak it up in a vacuum" - that's a technical term, I forget the proper one - epoxies Cope et al are using are only good for 2 atmospheres. At 100 metres if you are trying to keep something at sea level pressure you're looking at a 10 bar / 145 PSI pressure difference and nothing noone nowhere I've seen has made a 3D print capable of holding that.

Fortunately the breathing loop on a rebreather stays at whatever the ambient pressure is so you're not fighting pressure, you're just trying to keep water and gas apart from each other. Unfortunately, it means plastic choice in the loop becomes restricted because the off-gassing of plastics which continues for months after melting or mixing them up can kill you at the ambient pressures involved.

At least one rebreather manufacturer has had a serious crack at 3D printing loop parts and given it up as a bad job for now. I'll keep trying, I'm sure I'll get there eventually

[DavidF]

David, I think that 20% infill may come back to bite you if the ROV reaches a depth that can exploit the air pockets.

g.

The prints are so porous that it doesn't matter, geneb - I've printed parts at 25% infill for my rebreather that I'm diving to 60m with no problems at all but these are structural parts, nothing involved in trying to keep gas and water separate yet until I get a way of holding a decent seal. Which I suspect will come down to using the print as a plug for a silicone mould for epoxy or polyester parts.

Haven't noticed a problem with porosity on the pla printed parts, abs, different story..
Worst comes to worst ill be investment casting the pla printed parts directly.
The rov was designed to have all its parts machined, but I really don't have the time to do that. My equipment is all manual, so it would be very time consuming.
Printing the parts keeps my time freed up, let's me physically see the parts, and when printed with heavy walls and infill has great strength. So far all of the printed parts sink, except for the trailing arms which are ever so slitely bouyant.

[GBIADS]

After reading through this I think you are building one fine machine.

[foshon]

I've had extremely limited success with vapour baths for ABS to get a 1 bar (14.5 or so PSI) seal but it takes a fair bit of mucking around. Even the "soak it up in a vacuum" - that's a technical term, I forget the proper one - epoxies Cope et al are using are only good for 2 atmospheres. At 100 metres if you are trying to keep something at sea level pressure you're looking at a 10 bar / 145 PSI pressure difference and nothing noone nowhere I've seen has made a 3D print capable of holding that.

Fortunately the breathing loop on a rebreather stays at whatever the ambient pressure is so you're not fighting pressure, you're just trying to keep water and gas apart from each other. Unfortunately, it means plastic choice in the loop becomes restricted because the off-gassing of plastics which continues for months after melting or mixing them up can kill you at the ambient pressures involved.

At least one rebreather manufacturer has had a serious crack at 3D printing loop parts and given it up as a bad job for now. I'll keep trying, I'm sure I'll get there eventually

I would love to see some tests run by you water lovers. I am curious what effect varying depths would have on various percentages of fill. I'm a drylander, all I can do is wonder.

[DavidF]

Well I redesigned my tracks to standardize them to roller chain and started printing up the sprockets and some track for testing. Boy this is going to be one of those long long projects.....
[img]http://i1102.photobucket.com/albums/g446/davidflowers1/utf-8BSU1BRzA3OTkuanBn.jpg[/img]

[teoman]

Is that pla or abs?

And whatbare you using to stick on to the bed?

[teoman]

Is your rov a commercial project or a hobby?

I had also built an rov once upon a time. Great fun. But it can be fustrating at times.

[DavidF]

Printing white pla on glue stick. The ROV is my pet project that I have been playing with for about 2 years now off and on. Seems like most of the time spent has been redesigning things. Oh well maybe one day Ill get it done....