3D scanning - on the cheap!

[bwi 971]

I have a micro lathe - now selling - cheap!

So you are going to print brass, stainless steel,..... too?
How about buffing parts like prop shafts,
how about chamfer parts you have just cut,.....

Wish you luck sir.......doing all those things on your shiny china printing machine (SCPM)....You should keep your lathe……......you are gona need it, sooner or later.

Use your SCPM for what it is designed for…........but don't neglect/disrespect traditional machines and craftsmanship.

Grtz,
Bart

[Subculture]

Okay. Well if I was going to print an endcap, I would design it very differently to the one you've shown, as it makes very little use of the advantages of printing versus machining from sheet stock or casting. I would make the endcap hemispherical or ellipsoid, to thin it out and retain best strength, or if it has to be flat I would honeycomb the centre section. This will give the same strength as solid, but hugely reduce print time and material used, and should produce less shrinkage in the part as it cools off. I'd also look at integrating shaft seals in the printed cap as far as practicable.

[Kazzer]

The reason I used disks in the program, is that it seemed the simplest way to step the various dimensions. Using the SNAP tool, brings them all together.



I think folks are misconstruing my intent here. I am not doing this to produce endcaps for my use, or for anyone else. I have dozens of Mr. Merriman's molds and I can churn out any size endcap in a flash, if I wanted one. I also have plenty of seals, already made. As for building seals into the actual cap, I think that would be a folly, because if the seal failed, surely it would be impossible to replace it. With seals in their own housing, Merriman seals can easily be replaced, simply glued in place with silicone. Therefore, I only need to punch the holes using the EXTRUDE tool in negative to pull the hole through the solid.
Here's the hole punch - I snapped it to the center of the disk.



If this has any use to me, it's to send our design to someone who could reproduce it economically, like China.

I like the idea of making a honeycomb to speed up printing and reduce heat buildup, and will bear that in mind in future. Thanks

[trout]

Drawing it out is fine, the honeycomb can be set in the printing, but really there is more of a learning curve. Things such as bed alignment, warping pieces, not getting it to stick to the build table and temperature control come to mind. As long as your Chinese 3D printer is open source you will have options. If it is not open source, the working through their program or drivers will be a possible headache.
Mike once you get a few prints under your belt, you will then get the feeling of how things flow.

[Subculture]

As for building seals into the actual cap, I think that would be a folly, because if the seal failed, surely it would be impossible to replace it.

Design housings to accept simmerrings, which can be used for both drive and control shafts. These can be simply pressed in or out for service needs. Alternatively if o-rings are desired, then bayonet locked/latch could be printed making seal replacement a snap. These are the sort of things 3d printers shine at, adding things like bayonet latches using conventional building techniques would add complexity and cost to the production. A 3d printer doesn't really care how complex the part is, all that matters is volume, and how the item is supported during the printing process.

[Scott T]

Since it is said the outside dimension of the pipes is kept at close tolerance why not make a coupling type piece that silicone glues to the outside of tube.
Then the inside of the coupling that accepts the end cap can be molded/machined to keep close tolerances.

[bwi 971]

you smart man you Scott....thats good thinking.

Grtz,
Bart

[trout]

Scott is truly a brilliant man. He thinks of creative solutions and suggestions. Thanks Scott!

[Kazzer]

My 3D printer kit eventually turned up today. I think the hurricane on the east coast messed them up because my package was due last Friday, but turned up today. I was hoping I'd be able to spend the weekend setting it up.
Anyhow, it's here and today I started putting it together.






The parts are all precision cut and fit perfectly. I was immediately impressed with the packaging, and all the black parts are 1/4" thick acrylic sheet, even coated in paper to protect the parts. Actually the most difficult part is removing the paper - so far.
The stepping motors look extremely well made and I'm confident I'll have the machine assembled in quick time. My worry is the wiring, but if the videos supplied show how that is done, then I should be fine. So far I'm impressed with the videos.

I've even got my wife excited about this gizmo. She usually rolls her eyes when I mention submarines and models, so there's hope yet! I've even been allowed to do this in the kitchen! (My workshop is a disaster lately)

[Kazzer]

AND -- this kit cost $215 including shipping from China. I think the Chinese don't care whether they make a profit or not as long as they extract money from our economy. No wonder we have such a deficit.

[Kazzer]

I've actually finished assembling the kit, and no shortages, everything fits and it was a fairly pleasant experience. The videos helped a lot and were on a small card. All the tools were also supplied. All I have to do now is read the flippin' manual and plug it in.






I'm really impressed with the quality of the parts, and the precision everything went together. Maybe tomorrow I'll fire it up!

[Kazzer]

My first attempt at printing wasn't so good. I ended up with a load of vermicelli strings, not bonded to each other. It looked a little like a fishing net lattice. So, I've obviously got something wrong. Perhaps the extruder head isn't hot enough, or it is too far away from the bed. Maybe even a bit of both?

[trout]

Many 3D printers will want you to put something down to help stick those first few layers. Many people use Blue Painters masking tape. You are correct about not getting close enough to the bed can also create a mess. Did any of the base print? If so, I would lean to laying down a layer of tape.

[Kazzer]

The kit had tape, and I covered the platen with it, so it wasn't that. I'll give it another go tomorrow.