Next, pound the stake into the ground on either side of your 25 lb. log (or pole).
Drill a small socket at an oblique angle into the far end of the log, and you're now ready to start a fire (tinder, of course, will be needed as with any friction fire). Lift up the socketed end of the log and place the spindle top into the socket. Set the bottom end of the spindle into the fireboard such that the spindle is almost straight up and down. (A relatively stout spindle will be needed because of the weight of the log.) The log will now provide the downward pressure, and all you have to do is roll the spindle back and fourth between your palms! I have experimented with this method, and found it to work very well. I also discovered that with the heavy weight of the log, a larger spindle was easier to turn than a small one. The spindle I used was about 5/8" wide at the large end.
There are probably many other possibilities for a friction fire, including a cranking technique that Mike and I discussed. But for now, I'm happy to know a hand-drill method that works like a charm!
The ultimate fire starting gimmic - The Two-man Hand-drill set from Dick Baugh.
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EXPERIMENTS WITH THE HAND-DRILL
By Evard Gibby
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When experimenting with hand drill fires, I somewhat by accident discovered a useful technique.
I was using teasel for the drill and clematis for the fireboard. This is a combination that has worked well for me before. But this time the teasel spindle seemed to be drilling or cutting rapidly through the fireboard without producing an ember. Teasel has a hard outer layer and a pithy center, so as it is drilled it forms to the configuration as shown in the cross section (figure #1). So just as a change I grabbed a willow spindle and turned it a few times in the clematis fireboard with a bow, easily getting an ember. Spinning the harder willow spindle in the hole caused the fireboard cross section to look like (figure #2). Then I went back to the teasel spindle and again spun it by hand. To my surprise I was able to get an ember easier. After examining the equipment, the fireboard and spindle cross section looked like (figure #3). The now slanted sides of the fireboard hole caused the sides of the spindle end to conform to that shape.
Since then I have been able to start numerous fires with this same hole and spindle. The cross section has remained fairly constant, and at this time the hole has only worn down about halfway through the thickness of the fireboard, most of the wear being caused while obtaining the original configuration. I would say that well over 90% of the wear is to the spindle during operation of the equipment.
The reason, I feel, that embers are easier to obtain is that the slanted edges of the spindle and hole provide more surface area rubbing against each other, and consequently more heat, during the operation of the hand drill set.
It would be interesting to learn if others have the same results trying the same thing.
PUMP-DRILLS
Their Design, Construction and Attunement
Text and Photos By Anthony Follari
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In the past, I have manufactured and used several pump-drills. I was never really impressed with their performance and used them mostly for drilling small holes which didn't require much torque. My opinion changed, however, when I met my now good friend and firemaking colleague, Charles Worsham. Charles demonstrated and let me operate a firemaking pump-drill he had made. It worked smoothly, effortlessly, and appeared to have substantial torque. To put it simply, I was impressed and became motivated to start construction on a new pump-drill. I set a goal for myself: to construct an efficient operating pump-drill that could be made quickly and easily using only stone tools. It had to be versatile so it could be used for firemaking and drilling, yet small and light enough to conveniently pack or transport. A tall order perhaps, but not an unreasonable one.
I had seen an unusual antique pump-drill that was used during the colonial period and its design intrigued me. It had two opposed weights outrigged on a crosspiece as compared to the more traditional round flywheel. This design appealed to me. I felt I could successfully reproduce it using stones for weight. This would give me the flexibility to easily adjust the flywheels weight by simply changing stones and decided to create a flywheel assembly out of two cross-pieces which would hopefully sandwich the stones securely in place. (Stone flying off full speed at groin level would not be fun.)
I decided to construct a model out of lumber first to see if and how well this new flywheel design would work before I attempted one with stone tools. I also decided to make this test pump-drill extra large, trimming any excess off after I settled on effective dimensions. Since the weight was going to be adjustable, I decided to make the entire pump-drill adjustable. This way I could vary the height, width, weight, etc. and instantly see what impact these changes have. I could, in effect, test many different pump-drills, but only have to make one. This experimental adjustable pump-drill turned out to be a real educator. It confirmed for me that my method of securing the stones would work well. It also allowed me to study the physics involved in designing, operating, and tuning a pump-drill. After arriving at some dimensions for my new pump-drill, I gathered some basic stone and wood tools and began construction.
Using a stone axe and wooden wedges, I chopped and split out one upper and two lower cross-pieces from a four inch diameter tree. Using a bow-drill, I burned the large center holes through each crosspiece. The spindle was shaped from a branch using stone flakes and a hole for the chuck was drilled in its end with a stone and wood tipped hand drill. With two river cobbles and some cordage I completed the drill. To test its performance, I inserted a basswood fire tip into the chuck and started drilling on a cedar fireboard. Within 30 seconds I had a substantial coal. The drill turned out to be a success.
Since that time I have made numerous pump-drills and have performed many experiments in an attempt to learn more about the elements that can affect the efficiency of a pump-drill. My favorite pump-drill to date was constructed with only primitive tools, it is durable, portable and very efficient, producing a coal in less than 15 seconds.
What I would like to share is my approach to constructing and tuning a pump-drill using only stone and wood tools. The design I have been using can be constructed with relative ease. To demonstrate this, we will start with a tree and record our manufacturing time until completed. We will spend very little time on aesthetics as our focus will be on how quickly we can make a durable, efficient pump-drill. Please keep in mind that although I feel confident about designing, tuning and using pump-drill, I am not claiming to have all the answers. I am constantly experimenting and revising as I learn more. I welcome any and all comments and question. With this in mind, lets build a pump-drill.
A variety of finished sets on display and ready for use.
All cutting was performed with stone tools.
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While searching for the materials for this project I came across a three inch diameter tree that had been damaged and was dying. Although it was not the ideal tree I felt called to use it. Not only would it demonstrate that less than perfect materials can be used successfully, but it would be more in-line with my philosophical views regarding selection and harvesting. I hope you use the same approach and select a tree that can meet your needs while impacting minimally on the ecosystem.
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Constructing Pump-drills
To begin, first determine what you will be using your pump-drill for, then construct it with sufficient size and power to perform that job. If you intend to use it for more than one purpose, design it to handle the most demanding one. For example, if you are going to use your pump-drill only for drilling, design it around the largest drill bit you expect to use. For firemaking, select the largest and hardest fire tip you expect to use. Larger, heavier pump-drills have more power and can handle more difficult jobs. But bear in mind too large a drill can crush finer stone bits and fire tips and actually punch through wood. If portability is a concern, you should design the s
mallest, lightest drill that can be used for firemaking and drilling. We will design and tune it to handle a 3/4 inch diameter yucca fire tip. We will intentionally be overbuilding some components of the pump-drill and reduce them once it's completed. This is to prevent any one component from affecting the tuning by being undersize. If your pump-drill's purpose requires substantially more or less power then our example, you should proportionally increase or decrease the dimensions given in this article. The approach and tuning information would remain the same regardless of the size pump-drill you construct.
The next step is to construct the components of the pump-drill. There are three main components: the vertical upright section or spindle, the large horizontal crosspiece which you place your hands on to operate the drill, and the two lower crosspieces which make up the flywheel assembly.
Spindle
Select a straight hardwood branch about 30 inches long and about 1 1/8 inches in diameter at the larger end (Photo 3). Remove the bark and slightly round both ends by abrading them against a large stationary stone (Photo 4). To ensure that the lower crosspieces wedge and fit tightly into place the spindle should gradually taper to about 7/8 inch at the tip. If your spindle doesn't naturally taper you can scrape it to shape using a large stone flake (Photo 5). Next, abrade a notch across the top end the same as you would for an arrow nock (Photo 6). This notch is for the crosspiece string to ride in.To complete the spindle you need a method of holding the fire tips and drill points. You could notch the bottom of the spindle and design your fire tips and drill bits to match. This method would require a lashing to be tied and untied each time you change fire tips or drill bits and works well in situations where bit slippage is a problem. I have come to like a collet-type chuck best. It is a little more difficult to make, but if designed properly, works great. Shaping fire tips to fit this chuck is relatively simple. All your drill bits, however, must have the appropriate size foreshaft. This may require more work initially, but will make changing bits much more convenient.
Photo 3. Chopping out the spindle section.
Photo 4. Rounding the ends by abrading.
Photo 5. Tapering the ends on a stone slab
Photo 6. Notching the top end of the spindle.
Photo 7. Stone drilling.
Photo 8. Splitting the chuck.
Photo 9. The completed chuck.
To make the chuck, first pre-drill a hole straight into the bottom center of the spindle. I used a hand-drill with a 9/16 inch wide stone bit (Photo 7). This bit drilled a hole about one inch deep tapering to a point. Next I redrilled (actually burned) the hole with a 9/16 inch diameter wooden shaft to enlarge the hole a full 9/16 inch its entire depth (Photo 10). (If your hole is off center or drilled at an angle, chop it off and start again as a crooked or off center hole will not allow the drill to spin properly.) Next, split the spindle around the hole into six evenly spaced sections. The splits should run in about two or three inches deep, measured from the end of the spindle (Photo 8). To accomplish this I used a narrow, sharp bone wedge. Once the splits are completed insert your fire tip. It should be a snug fit, spreading the splits open slightly. Tie a piece of cordage tightly around the spindle about 1 1/2 inches from the bottom, then force the cordage downward against the taper to tighten the chuck. At this point the spindle is complete (Photo 9).
Photo 10. Burn-drilling the chuck. Split stick vice is used to prevent the spindle from turing and splitting.
Crosspieces
In total you will need three crosspieces (Photo 11). One upper for the hand piece (approximately 30 inches long) and two lower ones for the flywheel assembly (about 8 inches long). My first primitive pump-drill was made out of hickory. I selected hickory because I thought it would make a strong durable pump-drill. It did. What I didn't anticipate was spending 45 minutes burn-drilling one hole, not counting rest periods.
Photo 11. The cross pieces.
Pre-drilling with a stone tip shortened my burn-drilling time to 35 minutes per hole. Remember you need three holes, so if time is a concern and you are willing to sacrifice some durability I recommend softer woods like sassafras, cedar, etc. All the crosspieces can be split out of one block of wood. Select a straight, knot-free section of wood that appears to have all the bark furrows going in straight lines (an indication that the grain may also go and split in straight lines).
Chop out a 30 inch long section from the tree you have selected (Photo 12). You can use wooden wedges and a mallet to split the wood down into 1/2 inch thick strips (Photos 13,14 & 15). Pick the best strip for the upper cross-piece and chop out two 8 inch strips for the lower cross-pieces from the remaining strips. Abrade the rough edges by rubbing them against a coarse stone (Photo 16). With the crosspieces prepared it is now time to drill the large center holes.
I used a modified bow-drill arrangement to actually burn through the crosspieces. When burn drilling holes of this size I found that I needed a large diameter spindle which shouldered down to the size hole I wanted to burn drill (Photo 17). This allowed me the leverage to overcome the pressure and resistance I needed for burn drilling without the spindle binding or the cord slipping. (This and many other designs have many firemaking applications that will be discussed in a future article.) To facilitate the burn drilling you can pre-drill the holes with a stone bit. The size of the hole for the upper crosspiece should be about 1 /8 inch larger than the thickest portion of the spindle the crosspiece must pass. The lowest crosspiece should wedge down and stop about four inches from the bottom of the spindle and the center crosspiece about 2 1/2 inches above that. If your weights are thicker or thinner adjust this distance accordingly.
At this point, the individual pieces are completed and you can assemble your drill. For a starting point, select two, 3/4 pound weights and lash them securely between the two lower crosspieces. For weights, I prefer river cobbles that are flat and longer than they are wide. Try to find two stones that match as closely as possible in weight and shape. If there are any irregularities, they can be flaked, pecked or ground off. For a quick fix you can wrap buckskin or cordage around an undersize weight to enlarge it. You don't have to limit yourself to rocks either. Once, for a demonstration, I used my moose billet on one side and two small hammer stones on the other.
Photo 12. Selecting a section.
Having completed the lower crosspiece assembly, tie each end of a piece of cordage to each end of the upper crosspiece allowing a slack cordage length of approximately 39 inches. Now place the crosspiece over the spindle and place the center of the string in the notch. Your drill is now ready to be tuned. Before I move on to tuning, however, I would like to review the proper way to operate your pump-drill as the operator can greatly affect its performance.
Operation of Pump-drills
To get the most performance from your pump-drill, it must be operated efficiently. You should accelerate the crosspiece down authoritatively, yet smoothly, generating as much force as possible early in the stroke, as this is when the pump-drill has its greatest mechanical advantage for generating power (Photo 19). As the crosspiece approaches the bottom, the operator, anticipating its rise, offers and maintains downward resistance putting to work the flywheels momentum. Then, as the crosspiece reaches the top, the operator gets ready to start again.
Photo 13. Starting the split.
Photo 14. Maintain even mass onboth sides of the split.
Photo 15. Select the fatest, most uniform piece for the handpiece and chop the lower pieces from the remaining split.
It's common for people not to apply any resistance on the crosspiece during the upward travel, thinking it will hinder the drills performance. This may be true with a poorly designed drill as it may lack the necessary momentum and stall, but a properly designed and tuned pump-drill will easily handle downward resistance during its rewind enabling it to more efficiently utilize and generate power.
Tuning Pump-drills
With the construction and operational aspects behind us it is time to
concentrate on tuning. There are several factors which affect the pump-drill as the crosspiece goes through its upward and downward travel. Tuning consists of adjusting these factors to maximize the pump-drills efficiency. We will take a three step approach to tuning. If your pump-drill has the same or proportionally the same dimensions as our example these steps will apply. If not, refer to the trouble shooting guide as some of the components of your pump-drill may be undersize and prevent you from selecting the proper setting.
Step One - Adjusting the Revolutions Per Cycle
When the pump-drill is being operated the spindle rotates in one direction for a certain number of revolutions, then it reverses and spins in the opposite direction for an equal number of revolutions. By adjusting the number of revolutions that take place during a cycle you can have a tremendous impact on the drills performance.
The revolutions per cycle are determined and can be adjusted by the length of the string attached to the crosspiece. The shorter the string the fewer revolutions per cycle and conversely the longer the string the more revolutions per cycle.
Primitive Technology Page 9