Printing With Supports, DC Fittings

I started off wanting to create more custom dust collection fittings.  This time for my router table.  I need something to go from the back of the fence to the dust hose, and take a tight 90 degree turn.  I quickly came up with a 3D design that smoothly transitioned between the two diameters.

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This isn’t a simple print.  Previously I used a PVC elbow to make the turn, but I wanted to work on my support skills. The shape starts large on the left, but gets smaller on the right.  That means very little is ever touching the print bed.  I knew this would require a lot of support material to work, but thought it would be a good challenge to fiddle with support settings so that bottom surface was as smooth as I could get it.

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The slicer software shows in green the support material.  I can only print one material at a time.  What it does is tries to make a very sparse little structure just below the main model surface.  The printed model will droop a little bit, but hit the support and not droop any further.  If you get it right, the bottom looks good, but is able to be broken away from the support.  That is the theory at least.  In practice, anything I have printed with support has looked horrible on the bottom.


I started with the default settings that were recommended for my printer.  Instead of printing the whole thing I only let it print the bottom bit just past the support.

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It made it out alive, but looks rough.  The bottom layers are pretty loose and separated from each other.  Could I improve on this?

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Not really as it turns out.  One trick is to reduce the print temperature.  If it is cooler it will solidify faster and not droop as much.  I also tried modifying that support surface to be more solid so it would offer smoother support.  On every one, the edge would peel up and get caught by the nozzle.  They all failed at roughly the same spot.  No big deal, go back to the settings I started with.

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The left one was the original settings, and the right one had the support structure even closer than before.  All of them fail in the same way, that thin bit on the bottom right bends up and catches the nozzle.  Printing the support with no gap would make it hold well, but might make removal difficult.

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Ok, the print didn’t fail, that thin bit was firmly stuck down, but the support structure is welded on there.  Time for a re-think.


I wanted elegant, but now I am going with simple.  Instead I printed a tube to connect to the hose, a tube to connect to the router, and a block with a swept section that connects the two.  5 minute epoxy is the universal force that binds us together.

This lets me print each segment in the ideal orientation and then put them together later thus maximizing the ability of the printer in each situation.  The final result works well.  So much for increasing my supported print skills.

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Sander Dust Collection Fittings

This falls into yet another “project I started over a year ago” category.  Not sure how it fell off the radar, but it did.  Dust collection is a wonderful thing to have, but there appear to be no standards.  Every piece of equipment has a different hose size.  I wanted to plumb my two main bench-top sanders together in a clean and easy way.

I started by adapting the back of my spindle sander to a PVC elbow, and then to a ribbed segment that would accept some flexible hosing.  5 minute epoxy is all you need to join the plastic pieces.

I cut a small length of hose and attached another hose coupler.  One side is ribbed to keep the hose from coming off, the other is smooth.  The hose slides on and off easily, but seals well enough to be a good vacuum.  I printed some mounting blocks that have a path through them to pass zip ties through.  This holds the coupling down without any complex clamp mechanisms.

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Similarly I went to the stand that has my disk/belt sander and attached hosing so I could get to it on the side of the machine.

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Now the vacuum built into the disk/belt sander can service both it and the spindle sander with just a quick re-plumb.  Cheers to less dust in my lungs!