Thursday, December 9, 2010

Power Tools Trial and Error

Before I had the opportunity to work on any of this stuff I used to spend a lot of time planning how it would go.  I spent several years looking for websites of other people who may have done something similar so that I could hopefully learn from their successes and failures.  Since the point of all this is how to spend as little as possible, I thought I would go ahead and document my "investment" screw-ups.  So if you are about to spend a bunch of money on tools... this is for you.

So I had some land, but would not have power for quite a while.  With this in mind I decided to get a bunch of rechargeable tools.  My general policy is to go ahead and spend extra to get tools that will last (within reason), so I bought mostly Dewalt 18 volt since they seem to be the top on the consumer line and generally had good reviews.  My first mistake was buying them in pieces.  I needed a reciprocating saw while I was clearing land so I got that.   Then I discovered that the battery only lasts for a couple of minutes of run-time, so I got a couple more batteries.  Then I needed a drill so I got that.  In the last couple of days I needed a circular saw.  Luckily my dad gave me an extra black and decker 18v... so at least I did not have to buy one of those.  Buying these in pieces at the local Lowes was my first mistake.  If you get them as a whole set you will pay a lot less.  Also Amazon is about 30% cheaper.

Some tools work very well off batteries.  You can accomplish a lot with a Dewalt 18 volt drill.  Other stuff I have to conclude was not really meant to be cordless.  I would say reciprocating saws and circular saws fall into this category.  With a new fully charged battery I get about two minutes out of the reciprocating saw... which is not great, but may be worthwhile as you can cut a lot of limbs and small trees with two minutes of run time.  The circular saw (Black and Decker) however is almost completely worthless.  Basically on a full charge you can cut an untreated 2x10 about 6 times.  I spent the last four days cutting steps out for a staircase to the trampoline.  The reciprocating saw could have done it but it is hard to make a straight cut.  I cut a few out with a hand saw but for some reason all my cuts ended up bending as I went.   In the end it took four days to do a 20 minute job because I had to keep driving 15 miles to recharge a battery to make six more cuts.

Having now spent over $500 on rechargeable tools I can think of a few alternatives that may have been better.  I would probably still get the cordless 18v drill.  That works great.  Instead of the reciprocating saw I would have just got a $20 axe or machete.  After that there are a couple of good options:

1. Get a Generator:  These can be found surprisingly cheap. has a variety of sizes but a 2200 watt generator which should run almost all power tools is about $300.  Then you can get the other tools you need used or at a pawn shop for almost nothing.  Also when all the building is done, you never know when you might need a generator.

2. Get an Inverter:  You can get a 2000 watt inverter for about $160 also from which you then hook to your car battery and let your engine idle.  Then use corded power tools from this.  If you plan to go off the grid at some point you are going to need one of these eventually anyway.

To find the max size inverter or generator you will need multiply the amps used by your biggest tools by 120 and add about 10%.  You will need at least that many watts.  2000 watts will run anything up to about 15 amps.

3. Get a bunch of old used rechargeable tools and "zap" the battery.  Last week we threw away about a dozen 14.4 volt battery packs that would no longer hold a charge.  Then a couple of days ago I find this:  I have not tried it yet but apparently you can revive an old nicad battery to where it is almost as good as new by briefly running a bunch of high voltage power into it.  The voltage needs to be DC and about twice what the battery capacity is.  This can be done with a bank of car batteries in serial, or a welder (about 40ish volts), or a capacitor from a disposable camera.  My brother has a battery that will soon be dead so I will let you know if it works.  BTW: be careful if you do this as the battery could explode.

Other possibilities that you can find fairly easily with a google search include modifying an old battery so that you can hook the rechargeable tool with a cord to your car battery. Or making an adapter so that you can use cheaper batteries from other manufacturers on whichever brand you end up going with. Both these really only require a little cutting and soldering and broken parts to accomplish.

One other thing I should probably mention.  If you are going to be ordering a bunch of stuff you might want to become an "Amazon Prime" member.  Basically for $80/year you get free second day air shipping on everything that is "prime eligible" which is everything shipped by them and some of their associates, which is basically most stuff.  I actually bought the $250 trampoline from them which weighed about 130lbs and they had to ship it free second day air.  I am fairly sure shipping for that was more than the cost of the trampoline.  Had I been feeling especially nasty I could have upgraded that to next day air for $3.  For people in rural areas this can save a lot of time an money in the long run.  Also now you get a bunch of free online videos with it... kind of like netflix.

Wednesday, December 8, 2010

Small Papercrete Mixer Version 1.

Behold my first papercrete mixer!  Well... actually the first was technically a five gallon plastic bucket and a paint mixer attached to a little cordless drill, but this one is a lot more impressive.

It started when my father showed up with this gigantic drill.  This thing is so huge that you would have to be somewhat insane to try to use it on just about anything.  The drill by itself weighs about 40lbs.  The new version seems to have a lighter casing.  This one is all cast-iron.  I am hoping some day someone asks me if I have a drill they can borrow to put in a few screws.  I can't wait to pull this out for them.

Anyway, I was getting ready to make a tow-mixer and was kind of wishing I had something for medium size batches that I would not have to drive around when drillzilla showed up.  $10 on a metal 55-gallon drum and some welding and I now have this thing.  Basically I put a bolt in the bottom of the drum facing inward, put a couple of washers on the bolt then welded a couple of lawn mower blades to a pipe to put over the bolt.  Then a bolt in the other end of the pipe for the drill to hold on to.  The rest is just a frame to hold the drill in place.


The first test lasted about 10 seconds... my welding around the bolt that the drill attached to broke and I had to reinforce that. On the second test it seemed to be going pretty well until the entire barrel started spinning and lurching all over the porch. I guess the torque from the drill was too much for the weight I had in it (about 15 gallons at the time). Like an idiot I grabbed the barrel while it was flopping around and forgot that the edge was sharp. I now have three impressive cuts on the ends of my fingers.

I decided the blades were probably too long so I cut the ends off, then I decided it was not mixing fast enough so I welded them back on at an angle. I am fairly pleased with the final result, it does not throw the barrel around when you turn it on, but it still mixes pretty quickly. It will probably help if I wet and tear the papers into strips before I throw them in instead of just throwing the dry papers in. They tend to get wrapped around the shaft if you do that.

Now as soon as we get power and water at the property I will have a lot of mixing to do. Since I doubt anyone would want to buy a $700 drill for this, the same thing could probably be accomplished with an auger powerhead for $200

Dome Progress Dec 8, 2010

Well... there it is. It is waterproof, strong, tight and looks like crap.

I was kind of hoping this shrink wrap stuff would look a lot nicer when done but that does not seem to be the case.  Again, if I had done this right from the start things may have been different.  The issue is that with the bolts sticking out the wrap gets hung up on them even when they are padded which prevents even shrinking and causes it to get thin and tear.  If I were doing this again I would have made sure the bolts were facing inward and the pipe ends were all rounded off so that the plastic would slide over the joins.  I would also have wrapped the entire thing before I tried to shrink any of it.  I would fold, cut and tape all the excess material and then tape all the seams before I started to shrink anything.  Maybe if I had done all this it may have turned out cleaner.

The gun did work a lot better, but I still managed to melt a lot of holes with the result being that there is now a bunch of duct tape patching all over the place.  So it looks like I am going to be using a lot of papercrete in the near future.  First I will probably go around the base to seal the dome to the deck on the outside and inside, then I will make panels to put between the structural triangles on the inside, then I will probably spray papercrete on the outside and paint over it.

A lot of this depends on how well the papercrete can be sealed against water.  I have some test samples drying at the moment, but it will probably take a week or so for those to dry in the current climate.  Were I doing this again I think I would probably skip the shrink wrap and try using pallette wrap... basically big rolls of saran-wrap that are about three feet wide.  Since I am going to have to papercrete over it anyway, this would have saved me a couple hundred dollars on the shrink film and $360 on the heat shrink gun.  Ah well...


Wednesday, December 1, 2010

Dome Progress Dec 1, 2010

DomeWell... the trampoline is in, that went very nicely.  The shrink wrap has been problematic however.  100ft by 20ft of 9mil fire resistant shrinkwrap was $270 including shipping.  This did not seem too bad.  The special propane heat shrink torch was $350 to $1000 however... which is bad.  My theory was that surely I could use something else to basically blow a lot of hot air.  My theory was wrong.

I tried everything.  Starting with a forced air propane heater.  This kind of worked, but very slowly, it also had to be inches from the plastic and tended to touch it occasionally with the heater rim which melted holes.  I spent a couple of hours doing a 10x8 ft section and it looked pretty bad.  The leaf burner and the blowtorch caused it to shrink very quickly but only in a one inch wide strip... also melted more holes.  I made a custom tip for the blowtorch out of copper pipes with a bunch of holes drilled in it to try to spread the flame into thin even strip, but the regulator could not be adjusted and it would not burn well.  I even tried boiling various water / salt / sugar solutions to see if I could just throw hot water on it.

In the end I had to break down and buy the stupid heat shrink gun.  It should come in tomorrow and better be a huge improvement... I don't know what I am going to do with it after I have finished shrinking everything, but for $350 I am definitely going to use it for something.  Maybe a water heater or home-made rotissary.  This is the cheapest heat shrink gun I could find:




So I heard about this stuff a while back, and did not think much about it until recently. I was looking into ways to insulate the dome and was considering putting fiberglass insulation on the outside and another layer of shrink-wrap around that, or cutting foam panels into triangles and attaching them inside. Both options would be about $300. Being fundamentally cheap and since I am quickly running out of cash I decided to look into other options which brings us back to papercrete.

Basically this is like a large cement spitwad. You mix newspaper with water and blend it up into an oatmeal like slurry then you add portland cement powder. There are variations on the recipe, but the most basic seems to be equal parts by weight of dry newspaper to dry cement powder. You can pour this into blocks or molds or forms, or spray or plaster onto screens, or walls. One bag of cement will produce about 40 large blocks which will weigh about 3 lbs each. It apparently has an r-value (insulation) of about 2.5, by comparison the foam panels are about r-value:3. It is also basically fireproof and can be made waterproof by painting it with masonry sealer.

Any type of paper can be used, but newspaper is usually available for free in bulk from the local newspaper printing company or recycling center.  The blocks are strong enough to drive over and will not shatter but will compress like a really stiff sponge.  They can be made stiffer and more fireproof by the addition of more cement and sand with the trade off being greater weight and less insulation.  Some people suggest adding borax to prevent mold and to further increase fire resistance.

The finished product can be cut with woodworking tools and will not fall apart even if it becomes wet.  People have made ponds with this stuff.  The real draw for me is that along with being practical and easy to work with, it is really cheap.  The only thing you have to buy is cement and $10 worth of that will get you over 40 large blocks.

I plan to pour it into one inch sheets then cut into triangles to put on the inside of the dome.  I have a batch drying at the moment and I made a small scale mixer out of a 55-gallon drum and a huge drill.  I hope to make a tow-mixer this summer for making blocks, but this should get me through the winter at least.  I will post more pictures of the test-blocks and the mixer later.  I am currently testing different mixes portland / masonry cement / sawdust / polyurethane / leaves etc.  The blocks in the picture are still very wet but quite hard, they have been drying for about 5 days now.  Winter is probably not the best time to be doing this.

More info: