I didn't even know what a slide rule was until a couple weeks ago, and now I'm obsessed. I have also had an interest in clocks for a few years, specifically pocket watches. The KL-1 satisfies both of those interests, and I have fallen immediately in love with it. I can't figure out why there weren't more models like them; it seems like such an elegant and practical way to make a slide rule. Anyway, thank you for the video. I'm quite excited to purchase my own soon, and I'll definitely come back here to practice using it.
an alternative that allows to perform chain calculations for multiplication as well as division is this: to perform a x b: 1. indicate 'a' under the index (ie rotate the scale so 'a' coincides with the fixed index) 2. indicate '1' on the needle 3. rotate 'b' on the scale towards the needle (this performs the multiplication by 'b', ie rotate over log(b)) 4. read the result under the index. to perform a / b: 1. indicate 'a' under the index 2. indicate 'b' on the needle 3. rotate '1' on the scale towards the needle 4. read the result under the index. The difference is where to locate the second value: below the needle, or below the fixed mark. The advantage of this method is that the result always ends up under the fixed index and can be used for a next calculation. (if a result ends up under the needle, it cannot be "transferred" to a subsequent calculation other than "manually".)
Another reason to use the fixed index as the result: to "transfer" a trig value 'a' (but not an angle) from the trig side to the other side, indicate 'a' with the needs, then flip over and rotate '1' to under the needle; the result 'a' becomes available under the fixed index.
Yeah lol. I don't know if there actually are a ton of clueless buyers out there or if some sellers just set ridiculous prices and don't mind sitting on these things for a few decades (or centuries) hoping one day they will actually be worth the asking price. With a little patience and luck, I've been able to win auctions for pretty much all of the most popular slide rules in perfect mint condition for under thirty bucks each. Kind of funny when you see a ton of the exact same rules in completely trashed conditions posted by random desperate sellers from places like Bulgaria trying to hock them for the bargain basement "buy it now" price of $250 plus something like $100 for shipping lol.
One additional trick I don't think I've mentioned is "quick" multiplication or division. It's an application of the inverse proportions. To multiply, move the needle to the first number on the trig side, then flip over and rotate the face so that the second number is at the needle. Result is at the fixed indicator. To divide, do the reverse: Start on the normal side. Rotate face so dividend is under the fixed indicator, then move needle to divisor. Quotient is now on trig side under the needle.
I want to make a circular slide rule for use as a flight computer (see E6B) and I want to know how it is I may figure out the degree spacing of the markings.
Here's the basic idea to get you started: Let's say a regular slide rule is length 1 from left index to right index, so that position 0 means the left index and position 1 means the right index. The mark which is labelled X on a regular slide rule's D scale is at position log(X) [base-10 log]. For example, the label 1 appears at position 0, the label 2 appears at position log(2) ~ 0.3010, the label 3 appears at log(3) ~ 0.4771, etc. Note that 10 should appear at log(10) = 1, the right index. For a circular slide rule, simply multiply the result by 360 degrees. The index is then at 0 deg (and 360 deg). The mark for 2 should be at 360*log(2) ~ 108.4 deg. A and B scales are half length, so just divide all length or degree measurements by 2.
I didn't even know what a slide rule was until a couple weeks ago, and now I'm obsessed. I have also had an interest in clocks for a few years, specifically pocket watches. The KL-1 satisfies both of those interests, and I have fallen immediately in love with it. I can't figure out why there weren't more models like them; it seems like such an elegant and practical way to make a slide rule. Anyway, thank you for the video. I'm quite excited to purchase my own soon, and I'll definitely come back here to practice using it.
an alternative that allows to perform chain calculations for multiplication as well as division is this:
to perform a x b:
1. indicate 'a' under the index (ie rotate the scale so 'a' coincides with the fixed index)
2. indicate '1' on the needle
3. rotate 'b' on the scale towards the needle (this performs the multiplication by 'b', ie rotate over log(b))
4. read the result under the index.
to perform a / b:
1. indicate 'a' under the index
2. indicate 'b' on the needle
3. rotate '1' on the scale towards the needle
4. read the result under the index.
The difference is where to locate the second value: below the needle, or below the fixed mark.
The advantage of this method is that the result always ends up under the fixed index and can be used for a next calculation. (if a result ends up under the needle, it cannot be "transferred" to a subsequent calculation other than "manually".)
Another reason to use the fixed index as the result: to "transfer" a trig value 'a' (but not an angle) from the trig side to the other side, indicate 'a' with the needs, then flip over and rotate '1' to under the needle; the result 'a' becomes available under the fixed index.
a translation of a Russian original seems to suggest the same procedure:
search for KL-1 manual at sliderule.ozmanor.com/man/man-download.html
Buy these on Ebay . Do not take any notice of the "RARE" descriptions . You should be able to pick one up for $30_$40
Yeah lol. I don't know if there actually are a ton of clueless buyers out there or if some sellers just set ridiculous prices and don't mind sitting on these things for a few decades (or centuries) hoping one day they will actually be worth the asking price. With a little patience and luck, I've been able to win auctions for pretty much all of the most popular slide rules in perfect mint condition for under thirty bucks each. Kind of funny when you see a ton of the exact same rules in completely trashed conditions posted by random desperate sellers from places like Bulgaria trying to hock them for the bargain basement "buy it now" price of $250 plus something like $100 for shipping lol.
Mine was $35, with shipping.
I bought one today for $27 including shipping
I bought a very pretty one with a good box and paperwork $40 shipped
u, sir convinced me to acquire one
One additional trick I don't think I've mentioned is "quick" multiplication or division. It's an application of the inverse proportions.
To multiply, move the needle to the first number on the trig side, then flip over and rotate the face so that the second number is at the needle. Result is at the fixed indicator.
To divide, do the reverse: Start on the normal side. Rotate face so dividend is under the fixed indicator, then move needle to divisor. Quotient is now on trig side under the needle.
I want to make a circular slide rule for use as a flight computer (see E6B) and I want to know how it is I may figure out the degree spacing of the markings.
Here's the basic idea to get you started:
Let's say a regular slide rule is length 1 from left index to right index, so that position 0 means the left index and position 1 means the right index. The mark which is labelled X on a regular slide rule's D scale is at position log(X) [base-10 log]. For example, the label 1 appears at position 0, the label 2 appears at position log(2) ~ 0.3010, the label 3 appears at log(3) ~ 0.4771, etc. Note that 10 should appear at log(10) = 1, the right index.
For a circular slide rule, simply multiply the result by 360 degrees. The index is then at 0 deg (and 360 deg). The mark for 2 should be at 360*log(2) ~ 108.4 deg.
A and B scales are half length, so just divide all length or degree measurements by 2.
Professor Herning thank you very much. That's precisely what I needed.
Great!