Project Choose Your Own Adventure

[Evan]

Im guessing the APAP motor runs on DC (24v?),  did you think about a DC to DC converter?  would be smaller and much more efficient.

here's a clip from the user manual (its a ResMed AirSense 10) thats relevant:



i never considered DC to DC...i'm not familiar enough about electrical systems to have ever thought of that.  so you're saying i could bypass the AC power supply completely and somehow hook a DC converter up to it?  i'm definitely intrigued although at this point i'm not sure its worth it to tear the AC inverter back out.

Yes exactly.   Going from 12vDC to 110vAC then down to 24v is very very inefficient.   Going from 12v to 24v is easy cheap and over 90% efficient.
The 2 battery thing like Adam said would work fine,  but then you have to have 2 batteries,  and they would be 24v only and you would have to charge with 24v too.  On the plus side its simple and nothing to break.
Id probably do a regular 12v,  wire 1 fused circuit to a 24v step up converter for the apap, and another fused 12v circuit for phone chargers and misc stuff. your charger can go straight to the terminals.    Get a good quality 5A step up converter and carry a spare.

[ScottyB]

We'll let you know if altitude impacts solar output as well via an 8th grade science fair project

thanks, and i'll be curious to know! we'll get out west soon enough and it would be cool to know what that could do for our power situation.

Some type of step up converter.

Going from 12vDC to 110vAC then down to 24v is very very inefficient.   Going from 12v to 24v is easy cheap and over 90% efficient.
Get a good quality 5A step up converter and carry a spare.

i'm going to do more research on this, although a quick look shows that they seem to be cheap and small which is great. i definitely hate the idea of throwing efficiency away especially in our application. as i mentioned, this isn't something that ever occurred to me, because ignorance. some thoughts:

• the APAP is a lease unit. i definitely don't want to do anything that would compromise it. to supply power, my guess is that i would need to find a plug like the one on the left of this image and then run the appropriate power and neutral lines to the step up converter? anybody know what that kind of plug is called?


• i should have mentioned this earlier but a travel-specific APAP unit called an AirMini is probably in our future as a long term investment since we're committed to carrying on with our camping/travelling dreams and its much more suited to that job. due to cost, its probably a ways off though. with that being the case, i'm not sure how far i want to go down the rabbit hole with fabbing another power solution for the current APAP since its likely temporary. the AirMini also uses a cig lighter charger which would work perfect with the 12v outlet we already have in the cabin. so, the thought on my mind right now is how many days of battery life could i get out of the current 120v AC situation before we'd have to plug in, assuming we had full shade or cloud cover so the solar couldn't charge.

No need for any converter. 2 12v batteries run in series will power that.

this is a great point but i don't have any room for 2 additional batteries as the camper was never designed for this in mind from the start. the tongue box is currently as full as it can get and the cabinet in the galley is already slated for our kitchen equipment.

genuinely appreciate the feedback and ideas. i am flying blind for a lot of this aspect of the build particularly as i have to pivot after the new power requirements. i think for now, with a much smaller and DC-powered travel APAP in the future, my goal is figuring out the least painful way to power the current APAP knowing that we aren't going to do any hardcore camping in the first year away from too many power sources (either plug in or solar exposure).

[ScottyB]

so i sat on my ass for a while and felt guilty about not working on it, then i felt guilty for working on it instead of other projects.  it didn't leave the corner of the garage.  finally my wife slapped some action into me and basically ordered me to pull it into one of the bays because if i did that, then i'd HAVE to work on it.  and she was right, as usual.  funny how these mental games can get in the way of obvious courses of action.

turned my attention to the galley and essentially finished the "center stack".  



installed the stereo and tested it. works great with my 2 6" speakers. radio reception is shit because i don't have an antenna yet, will fix that later. not easy to use but its cheap and it works for CD's and USB drives which is the main need.


then put on my big boy pants and decided it was time to make one of the last big pushes.  i actually dreaded this for a while, because its a multi-part leg of the project.  in order to put the outside "skin" on it, all the wiring has to be sorted and ready to be sealed up for good.  so, i spent a week sending more wire over the roof to the galley to finish out the wiring for the stereo, pantry light and USB outlet.  i also had to finalize the wiring for the roof fan and side "porch" lights.  then everything needed to be fully test, run through new holes drilled in the roof spars, and bundled up into one big artery of wires to run to the tongue box.

with that out of the way, the first panel went on.  "how many clamps do you need for something like this?"  well...how many do you have?


after nearly a year of having open doors it was so strange to see it sealed up.


...but not for long.  the openings were routed out with a laminate bit.  the bit simply "rides" the contours of the opening that already exists, so all i have to do is push the router along and it comes out great.  added some additional wood glue where the edge wanted to pull away a bit from the adhesive not getting to every little spot.


i made use of every reasonable scrap of birch sheet so the tail end was fitted with smaller panels.  attachment was via Loctite PL Premium construction adhesive and PL300 Foamboard adhesive.  this stuff is not to be f'd with.  once its on something its IMPOSSIBLE to get off and it dries as strong as concrete.


after it dried, i routed the edge with the same laminate bit and then wood putty'd the gaps, coarse sanded flat with 80 grit, and did a little block planing to knock down any high spots along with a finish sanding of 220 grit for now.  you can notice a tiny notch cut down the tail end.  that's to make room for the rubber seal that will run down the length of the hatch.


then stood back and enjoyed a thing that was actually starting to look kinda close to finished for a change.


it wasn't total victory though.  in going through my birch sheets i realized i was 1 short.  i don't know how the hell i managed that, but i'm not driving out to atlanta again to get a single sheet.  SO.  looks like the inside of the hatch is going to be open studs for the forseeable future until i figure out something cool to cover it up    just gotta roll with the screwups....

[JPolen01]

Love the progress! Keep on trucking man. Putting that exterior up had to be a huge hurdle.

[Senor_Taylor]

Wow! Amazing! Such a large project hopefully nearing completion

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[Beej]

Hot damn it's really starting to take form now. Awesome awesome work.

Hilarious that putting it in the way is a kick in the ass to get it moving. Humans are funny.

++clamps

[Evan]

It must feel amazing to look at that and say to yourself. "I built that"

great work

[ScottyB]

thanks everyone. the closer i get to the end, the more i realize i still have a good long way to go. its been quite a challenge and i'm not sure what i'm going to do with myself when its done and i have all this free time again (HA!)

[Sijray21]

It must feel amazing to look at that and say to yourself.  "I built that"

great work

yeah, this.

amazing.

[Kaan]

brian needs one of these for his S2000 to tow to the track.

[Senor_Taylor]

brian needs one of these for his S2000 to tow to the track.

IDK who that is, but I bet Maeng would like this too.

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[ScottyB]

brian needs one of these for  his S2000 to tow to the track.

IDK who that is, but I bet Maeng would like this too.

an S2000 would probably barely notice it if wee miatas can pull 'em.  i've even seen people do it with priuses and old VW bugs.





they're definitely viable as track campers that could double as tool lockers and food prep areas.  i hope i can use mine that way at some point once i'm able to get back into HPDE's more.

[Steve85]

Fantastic! Glad you got the push to jump back on it! I can't get over just how clean all the joints and fitments look.

[ScottyB]

full strength GA sun today so i wheeled it out to finally test out the solar system and make sure its doing its photovoltaic thing before i seal it all up under insulation and wood.  you can see the 1.5" hard insulation getting run up the roof.  stuff's messy disaster to work with and to make matters worse, its highly static.  i'll be cleaning it up for years.


in order to get the rigid insulation to bend with the roofline, i'm cutting a series of table saw cuts through the length of the back that almost go through but not quite.  the resulting "kerf" the blade leaves allows a couple degrees of bend.  add 10 or 15 kerfs and you can easily get it to follow a round contour.

roughly accurate panel position on the roof.  will mount it with a hinge system for a rough ability to tilt it to catch direct sun.


YEAAAH BOYEEEEEEE.  after i realized i had my wires backwards, yellow went from blinky (fast charge) to solid which means its "floating" a constant incoming solar charge, just like it should on an already topped battery.


earlier work on the roof.  the black thing is the solar power wire "entry gland" for the external panel.  each insulation panel required a bunch of hacking, cutting, chipping, fitting, and then rinse repeat 5 times until just right.


the 2 tools of choice for cutting insulation panels and making wire channels.  my least favorite part of this by far.

[ScottyB]

nice rain last weekend so got the last of the insulation in the roof.  much easier on the more open radius at the top section of the roof but still not a job i want to do again soon.  

quick how-to guide
step 1: apply glue
step 2: tighten straps
step 3: throw your crap on the roof.  any crap will do.  



first roof panel getting adhered, second/last one went on yesterday.  screwed into the roof spars until the adhesive cures to help it contour.  shits gettin real now boys.


did a lot of this.  like, a lot.  probably 150 went in, and they all came back out.  took 2 battery swaps.


laminate bit made short work of opening the roof vent back up again.  


not shown: galley is basically done.  i didn't send screws through any wires (that i know of).  varnished the sides and inside the cabin and need to do another coat on all of it.  

current goals: within the month build and skin the galley hatch and order the aluminum skin and trim. need to double check my wheel size and order appropriate fenders. need to order both side doors.

big fancy goal: blue ridge parkway trip by october/november.  i'm feelin it.

[Senor_Taylor]

I believe in you! Great progress!!!

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[.RJ]

big fancy goal: blue ridge parkway trip by october/november.  i'm feelin it.

I'll join you

[JPolen01]

[ScottyB]

big fancy goal: blue ridge parkway trip by october/november.  i'm feelin it.

I'll join you

done and done.  you bring the dingos and we'll bring the floof boi

we're probably going to go south to north in NC over 3-4 days since its close.  no goal other than shake the camper down at slower speeds and hit up all the awesome trails/views and trout streams.  not sure if I'll have the roof rack mounted to carry bikes at that point so 2 wheels might be out for me

[.RJ]

My buddy around the corner has a teardrop, I'm sure I could bribe him with delicious hoppy beverage to arrange rental.