Monday, June 30, 2014

Making Windows

Ever since we bought Tortuguita, the forward windows have been leaking.  These windows span the forward cabins and the 5th cabin (The garage).  I re-caulk them every 2 month but they always fail.  The plexiglass on the port window is cracked and both are extremely crazed.

Well, this is not the 3rd world.  There are 3 local shops that do serious thermoforming of plexiglass.  We went to all of them and chose P&M Plastics.  Initially, I did not know what was necessary to make these new windows.  I thought there was a straight bend and it would fit perfectly.  When I got the first one out, I wanted to mark the center of the bend and guess what, it was a complex curving bend.

I went to P&M to find out how this would now work.  They would now have to heat the plexiglass in a huge oven and drape it over a mold of the window.  The mold had to be 50mm larger than the actual window.  What kind of mold, I asked?  Plaster, wood, fiberglass?  They showed me some small things but there was nothing like this in their shop.  So, I bought resin, fiberglass, and wood and glassed up a mold like they wanted.  They wanted to do both at the same time so we had to pull both windows and make 2 different molds since they were mirror images of each other.
What a mess


The cabin is upper.  The garage is lower right.

















Extend the windows with wood and foam
I screwed wood around the edge and then glued 10mm styrofoam to the wood to bring it up to be level with the inside of the window

















Apply mold release agent

Mold release agent is applied to everything or so the fiberglass form will separate.















Fiberglass was laid up on to the window and then reinforced with wood slats to help keep the shape.














I used my machete to pry the pieces apart and there we go.  One window mold.













Windows and molds at P&M Plastics

Return to Australia

We arrived in Brisbane on May 5th.  It was raining which was a good thing because when I got the wipers confused with the turn signals on the rental car, nobody knew.

It was a good thing we brought our car GPS or we would have been totally lost and the left side driving thing.  The traffic does flow nicely here.  The philosophy seems to be the driver as much responsibility as possible.   There are heaps (an aussie term) of Yield signs and Roundabouts.  Of course that means fewer Stop Signs and Traffic Lights.  When you do get stuck at a light, they seem to be much longer than in the US.  I don't mind this because you end up stopping a fewer lights.  All the lights are controlled by motion sensors and other intelligent planning, so the lights won't change if no one is coming.

We are only allowed to stay on the boat a few days while it is on land so we got an apartment by the week.  This, along with the rental car has really made it nice.  Instead of being stuck in a boatyard, we have been able to get out and enjoy the area, food, and drinks.  Drink Driving, as Aussies call it, it being clamped down on.  The have a TV show like our Cops show called RBT (Random Breath Test).  In 2 months, we have been through 5 blockades and had to do 3 breathalyzers.  Good thing I had only 'a few'.  I'm having enough trouble with the left side road thing that I don't need to be more confused with alcohol.

The first apartment we were in was on Chevron Island.  Convenient but a little run down.  We stayed 3 weeks but they filled up and we couldn't extend so we found another place out on Surfer's Paradise that is definitely nicer.  I have been sewing new window screens and headliners which would have been much more difficult on the boat that on a big tile floor of the Flat.

Catamaran Row, Gold Coast City Marina

The Universal USB Power Supply

There are so many devices nowadays that use 5 volt power from USB to charge or power.
On the boat I have an Ipod, Headlamp, GPS, Mifi (Wifi), and a USB Speaker adapter that all need USB power.
The nav station was looking like a rats nest so I decided to make a power supply box that would accept any voltage and output 5 volts on USB receptacles.

 I drew up my idea in Sketchup










Printed it out.  This photo is actually an earlier version where the cooling slots were longer.  Even though the printer didn't have trouble air printing almost an inch on the layer above the slot, I decided it would be cleaner to shorten the slots.



And here is the final product:
The box accepts any voltage between 1 and 40 volts and puts out 5 volts on the USB recepticals.


Now I need to mount it under the nav station, run power to it, and I can power or charge 4 devices without having to turn on the laptop.

3D Scanner

My first project for the printer was to print brackets to attach the plexiglass to for the enclosure.
Then I printed a spool holder so that the filament wouldn't bind and cause the printer to skip.

Somewhere along the way, during the snowy winter, the heel on one of Booker's boots shattered from the cold.  I had been telling her about all the potential a 3D printer has to fabricate broken things...so now I had to prove myself.  I removed the broken heel and tried scanning the boot.  There was not enough light for a good picture so I took a picture of the remaining heel.


I then imported the picture into Sketchup, the 3D drafting program.  I took measurements and scaled the image to be exactly the same as the original.











I then outlined the perimeter and the 6 mounting holes, expanded it to 3D, and printed it.







And voilà, here is the finished product:
(printer in background)



Friday, June 27, 2014

3D Printer

On a boat, there are plenty of plastic things.  The material is corrosion resistant but they have a limited lifespan.  Now comes the 3D printer.  I have wanted one of these for a while and had the perfect job to justify it.  When the rigging was replaced in Mexico, the turnbuckles were longer and wider so I was not able to reinstall the aluminum covers. 


The tubes had plastic tapered plugs in the ends that fit the cable and stud ends.  I was looking to fabricate the plugs out of PVC rod on a lathe but since I had to make 2 halves that would have to bolt together, the job got very complicated since the rod would have to be cut down the middle, tapped and screwed, then turned on the lathe.  Possible but definitely time consuming.

Along comes 3D printing.  I have been putting off the purchase for a year and finally bit the bullet.

There are some expensive printers out there but in the end, plastic extrusion is plastic extrusion.

I chose to go with the Solidoodle 3.

 

In a sense, you are buying a kit.  Do not expect it to work directly out of the box.  They need to be tweaked and calibrated.  There is a steep learning curve to operating them but isn't that what it's all about anyway.  I have had no electronic problems except when the USB cable got yanked out of the controller board and I had to rebuild it.  Otherwise it has been the mechanical issues such as :Printbed not flat, printbed rivets loose, Y-axis belt tension calibration, extruder feed calibration (firmware), extruder feed calibration (software), filament quality problems, extruder mount cracking, spool feed friction, extruder clogged, and extruder servo clicking.

The thing that I liked about this design was the print size of 200mm and that the bed moves only in the Z-axis and the price.  I think that designs where the printbed moves in the Y axis also have inherent problems attaining maximum print speed due to the inertia of a moving printbed.   I also like the MakerBot but it cost $2200 vs $800 for the Solidoodle and is of the same design.  I paid extra for a Kapton printbed which was a total waste.  The heated printbed, however, it a must.  Plastic will not stick otherwise.  An enclosure is also a must.  I like my plexiglass enclosure because I can see everything happening.  A metal case does not permit this.  It also makes for a fun first project.

Most everything is open-source but a from scratch build is not without pitfalls.  I could attempt one now that I have learned on this one but would have wasted plenty of time building one myself and not have had as good a printer.  You also need to have access to a 3D printer to print the major parts to make a 3D printer. (Catch 22) .

The Solidoodle was inexpensive but lacked manufacturing quality control.  There were loose rivets, loose belts, loose extruder frame and needed calibrating when it arrived.  Without some type of enclosure keeping the heat in and drafts out, the parts cool unevenly and warp.  Solidoodle makes a model that has a metal enclosure but I wanted a clear plexiglass enclosure to be able to look at this thing while it was printing.  This was a good move as so much of the troubleshooting required watching with a magnifying glass as it printed.  I was able to get it to print some mounting pieces for the plexiglass that I wanted to put on it.  Then it broke again for 2 weeks.  It was shredding the feedstock plastic.  I tried everything and as I was about to give up and chuck it in the closet, I tried a different spool of material and it worked.  I think that the cheap plastic has recycled content in it which has varying melting points causing irregular extruding.



Next, what to print!




Sunday, June 15, 2014

Winter at the Shore

Just trying to catch up with the blog.  Haven't posted anything since we left for the US last November.  We stayed at the shore until May 1st and tackled a pretty major carpentry project.  The stairwell in Atlantic Ave. had been getting perpetual cracks in the drywall.  The plan was always to cover it with wood and I bought the wood shortly after the house was completed in 1996.  So I have had this project on the list for over 15 years and finally had the time.  Since we bought the boat, we have been sailing the winters and the house had been rented in the summers.  Finally, since we are down unda with opposite seasons, the project was do-able.  Unfortunately, I didn't take a picture of it.