Nearly every day this week involved one or more friends dropping round and chatting for an hour or so.
I keep telling myself that's what it's like when you are "retired".
But I sort of have these plans . . .
Mind you sometimes I welcome the break.
Climbing all over this house part is getting quite strenuous.
I have been putting off doing the roof part because the welder only just reaches to the centre from each side and for the tricky parts I need to lift it on the fork lift.
So . . . DECIDE . . . JUST DO IT !!
This raised the question (which has been sort of running around in my mind anyway because of the gas regulations which require a minimum amount of non-closing venting) as to whether to have a roof vent. Although I am very partial to air conditioning I have this vision of going to sleep with everything closed up (ducted refrigerated air conditioning) and waking up dead due to lack of oxygen!!
It turned out to be convenient because "Sich" also wanted to get some "stuff" for his bus. A pleasant morning but with driving and then coffee which turned into an early lunch (mutual decision) there goes another half-day.
Sich has an all singing all dancing automatic rain sensing self closing satellite controlled whatever type of roof vent for his bus. I thought it was a bit over the top and the price too but it turns out if you want anything but a piece of crap you are going to have to pay about $400 !!
So after looking at quite a few the inevitable "FIAMMA" brand was decided upon.
This is a manual opening and closing type but has a shape which will cause negative pressure when travelling and hopefully keep the dust out (from this point anyway - it may well suck it in elsewhere . . .).
It also provides even when fully closed a labyrinth vent which is completely rainproof and helps to meet the gas regulations.
Finally back to the roof frames which now have to accommodate fitting this item in.
Again the inevitable "rivnuts" seems like the best idea so they are fitted into a frame made on the bench and then the whole frame offered up to the roof and welded in place.
And again from underneath.
As you can see this completes the roof main beams and there is only the cross bracing to do.
Finally with all the rest in place there is just a lot of detail work left to be done.
This is from the front.
The large low "window" type opening is just in case.
It aligns with the rear windows on the truck.
Many of the truck mounted motor homes have an access passage between the cab and the house. Although it is not legal to wander around he house while travelling it is generally included as a safety measure. There are apparently some places and situations in which it may be advisable not to exit the house but just to get in the cab and drive away.
In exotic travel situations it is advised to have the camp packed up each night so that it is possible to drive off like for example if somebody is wandering around outside with gun !!
In my case with the tilt cab it makes such an arrangement rather difficult but I have avoided putting any structure in the way just in case I manage to find some windows which can replace the truck cab windows which can be opened for emergencies. In that case I will cut the hole in the house and fit a matching escape hatch. In the mean time it is behind the cab out of the wind so it's lack of strength will not be a big drawback.
After all that climbing around for couple of days my back needed a rest so I decided to finish off the bed control mechanism.
I have managed to build it so far with reasonably readily available car parts so decided to keep with that theme.
While lots of clever electronic bits are available they are not easily sourced in out of the way places. I opted for simple car type relays and switches and analogue controls so if anything goes wrong in all likelihood a simple trip to the local car wrecker will provide replacement parts.
There is a minor complication in this circuit in that both the active and neutral wires need interruption as both need to be reversed to make the motors run backward. Normal car relays are single pole so you need to have two - one for each wire and drive them simultaneously. This leads to double the number of components but at $8.00 each brand new its not too much of a problem.
Until the proper fascia panels for the circuit breakers and indicators and the active and neutral bus bars are fitted I just mocked it up on a piece of plywood to keep it all together.
It works fine but I was a bit perplexed for a while by some switches which turned OFF when pressed in the desired direction rather than ON . . . seemed a bit strange.
Ended up using a three position switch instead UP - OFF - DOWN seemed logical.
Not visible in the picture is the in line fuse holder.
I couldn't find the fuse rating on the motor vehicle wiring diagram from which I took the wiper motors but I assumed they would be fairly substantial - maybe 15 amps.
Running two in parallel would require probably double.
The relays are rated at 30 amps each so they would be OK so I added a 30 amp fuse to start.
Being an inquisitive sort I wondered what sort of current was actually required. Being too lazy to set up a proper meter I decided a $0.50c fuse would be a cheap way to find out so I started replacing the fuse with 5 amp smaller versions in steps . . . when I got down to 10 amps with everything still running OK I decided to leave it there. . .
Lastly there were the limit switches to stop the movement at each end of the travel so it can just be switched up or down and left ( it takes approximately 75 secs to raise and 60 secs to lower - but if I cant wait that long it's going to have to happen on the floor) and can't be switched in the wrong direction and be over driven and break the mechanism.
It's going to be a tricky little exercise to find a way to make them inconspicuous.
Well at least it is now convenient to operate.
Tomorrow back to the welding.
The deadline to be ready for covering is rapidly approaching . . .
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