Welcome to Builder Bill's Wrinkles.

My Latest Power Tool Purchase

My old impact driver, sadly given up the ghost.

The other day when I went to use my favourite power tool, my Makita impact screwdriver, it wouldn't work.
What a bummer, I expect to leave a battery operated tool for months and months on end, without even opening the box, let alone giving it a bit of a blast and recharge now and again, and still expect it to work perfectly.
I must be a slow learner.  I needed it that morning, not after a check out and service job.
The photo of it on the right is from my screwdriver gun page.
On that page that I wrote about 18 months ago I made the comment, "if it got stolen I would immediately go out and buy another"

Well I did, but not immediately.  I huffed and puffed and went to our huge building/homemaker supply store (Bunnings for you Aussies}with the intention of buying a cheapie.   Come on! How much work have I got left in me at my age?   An $150 import should see me well into my dotage.
No chance, the young guy serving me had never heard of an impact driver, he kept pointing to drills and saying "this has impact".

When I finally got to a proper tool shop I quickly found out that the Chinese clone toolmakers have not yet got onto these things yet.  There are three or four quality manufacturers that make them, and they are all around the same price range, AUD$550 to $650.

• The three manufacturers that I can remember seeing are Panasonic, Hitachi and Makita.
• There was one model, around $700 that was a three in one.   That is it was a basic 1/2" square drive that would accept standard sockets, to which could be added a drill chuck and a 1/4" hex screwdriver socket.  Interesting for someone like a small engine mechanic maybe.
• There seems to be a general shift towards Li-ion (lithium-ion) batteries which are faster charging,longer lasting, more powerful and less weight than the older type.  Interestingly the Makita range still has the older (red) batteries, and they are a touch cheaper than the Li-ion type.
• One Way to reduce the price is to go for half capacity batteries.  Makita do this, but I am not to sure about other manufacturers.  The standard battery, say 14.4 volts, is rated at 3AH (3 amp hour).   I could have saved maybe $190 if I had bought a kit that used 1.5AH batteries.  This goes to show actually how much of a percentage of the tool cost is represented by the two batteries supplied with each kit.
• The top price one, over $1000, that I didn't see but was told about, is the (and here I quote from the web site, "Makita BTS130Z 14.4V Mobile Oil-Impulse Driver,  Makita built 4-pole motor design with dual steel ball bearing provides maximum torque. Incredibly low noise operation thanks to the impact mechanism using oil unit instead of anvil and hammer. Capable of long continuous operation with the cooling system for oil unit"
• "Mobile" is the new word for cordless.  So why would you spend over a grand?  The lack of noise makes it possible to use these in hospitals or other places, where noise would be a factor.

So here it is, a Makita BTD132 cordless impact driver.

• Is it worth the AUD$590 that I paid for it?   Well the old one cost only a little less a few years ago and that one certainly paid for itself.  There's an old saying that salesmen of all genres love to quote, "Tools (or trucks or machinery etc.) don't cost you money, they make money!"
• One improvement, that I hadn't picked up on, the old machine has 2AH batteries, so it was in fact closer to the 1.5AH cheaper set up.
• The new one has three separate torque settings through an electronic button which could be quite handy for wriggling in small joinery type screws.
• The charger is significantly larger, and contains a cooler fan that stops the battery from overheating.  In fact the manual recommends (yes, yes, I did read the manual) that the battery be left in position after the green OK light appears to further cool the battery.
• With these batteries they should be re-charged as soon as they show signs of slowing down.  No flattening them completely.

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A Square Peg In a Round Hole

A square peg.  These sketches are fairly exaggerated to make a point, in actual fact the taper and the twist is fairly small.

The old saying "you can't put a square peg in a round hole has always puzzled me.  It's just not right!  For centuries carpenters and boat builders have been doing just that.
In fact if you try to make your pegs fit the holes by rounding them off, then you are not doing the best job.  Round pegs just don't grip tight enough in round holes.  That's why we use glue or any of the dozens of fixings that depend on some sort of expansion force.

It may sound silly in these days of many different types of mass produced plugs, anchors and grips, but there is usually some odd bits of timber around if you happen to run short of commercial fixings.
Believe me it is always quicker and more productive to make up a few home made pegs than leap into your car and go to a hardware store.  (Plus it takes an iron will to come out of one of those places with just a single packet of Rawlplugs :-)

1. Pegs are usually split out of convenient sized timber with an axe or a chisel.
2. They are tidied up and squared with a sharp chisel.
3. A very gradual taper is put on them, if it is too steep, you will feel it resisting and wanting to pop out.
4. It is a traditional technique to put a slight twist into the pegs.
5. As the pegs are driven home the timber gets twisted and grips the side of the hole more.

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Twisted Plugs For Fixing Door Jambs

Showing no recent signs of use, and old plugging chisel, used to chip grooves in brick bed joints.  This particular one is a poor example.  A good one will have a groove on each face to help get rid of the dust and stop the chisel from jamming.

A twisted Plug, usually out of softwood.

Now this one is really a blast from the past, and I am not saying that this is what to do today.  There are better and quicker ways of fixing door jambs to masonry.
Personally, if faced with a power cut on a job, and with only a couple of door jambs left to fix, given the choice of finishing the job with a plugging chisel, or packing up and going to the pub, I'd probably go to the pub:-)

So this little technique is more in the category of "information only".

1. To fix a door jamb into a brickwork opening, circa 100BC - 1950AD.
2. Cut 8 plugs similar to the sketch out of say 3" x 1" softwood, about 6" long.  Once again, the twist is the main thing and it is done using a carpenter's axe.
3. Rake out the bed joints of the brickwork (four each side) to a width of 3" or 4" and similar depth with a plugging chisel.
4. Firmly belt the plugs into the opened up joints with the back of your axe, using a sideways stroke.  (Sometimes you get them in solid without splitting them. If you use a claw hammer they always split).
5. In an ideal world the brickie will have left between 1/2" and 1" clearance and his walls will be plumb.
6. Mark your top plug on one side half the clearance out from the brick.  get a level and plumb that mark down to the others on that side.
7. Get your sharp panel saw and cut the plugs off neatly.
8. Mark the other side measuring from the cut plug the overall width of the door jamb, plumb them up and cut off.
9. Place the door jamb in the opening and check the head for level.
10. If it is out of level then pack it up until level.  Only do this if there are floor coverings like carpets that will hide the gap, otherwise you have to cut one jamb shorter to make the head level.
11. Nail the jamb into position with say two 3" nails slightly skewed inwards.

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A preview of a new page about purlins

A sketch of different purlins on a steel beam or portal rafter.

The importance of steel in residential construction is increasing at a great rate.  Where I live we rarely see timber used structurally.
I intend to expand my series of articles on steel in residential construction because I believe that by sticking to timber construction methods many homeowners are spending more and getting less for their money.

The very first steel portal frame building that I worked on was in 1966.  Three of us formed a partnership and leased a workshop.  Part of the deal was that we had almost had to build the place first.

A detail at 1.) a joint of two timber purlins at a double punched cleat.

1. It is fairly obvious that joining timbers with bolts so close to the edge of the timber is extremely weak.  The chance of failure is high as the timber will split under load.  There are rules laid down for the minimum edge distances for bolts in structural timber.
   One way of solving the problem is to use wider cleats, to keep the bolts away from the end of the timber.
2. The way that we solved the problem in 66 was to use an extra length of purlin timber spliced over the joint.   The extra splice length was bolted to a standard single cleat, and the purlin lengths themselves were bolted to the splice, with 2 bolts at each joint with ample end distances.
   Reinforcing the joint like this is basic good practice, and it has an extra spin off in that the purlin as a whole is a lot stiffer and so stronger.
3. This stiffening effect of purlins doubled up had been long known, so that when steel purlins came along the designers must have pondered deeply to find a way to get the same effect.
   They found a way all right and they did it brilliantly.  They designed the Zed purlin.
4. Here we see a standard Cee purlin that is spanning across two bays, and as such it only need a single cleat.
5. This last one shows Cee purlins joined at a double cleat.  Because of their shape they do not have the ability to overlap at the joint, but they share the other attributes of modern roll formed sections that give them the edge over timber.  One of course is the ability to join on a double cleat.

Lapped steel "zed" purlins

• High strength to weight ratio means easier transport and less weight load on the support structure.
• They have well tested and consistent engineering properties, unlike timber which varies considerably.
• Steel roll formed sections are straight and can be made as long as it is practical to transport and handle on site.
• They can be supplied pre-punched and with all accessories needed to complete the roof structure.

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A Tip on Stair Ratios From a Reader.

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A page about a homemade stair jig.

One of the sketches from my page about making a jig to trench stairs.