For a 45 degree dovetail use pins that have a diameter of 41% of the dovetail depth. This way when measuring over the pins in both the male and female parts the dimensions will remain the same. For 60 degree dovetails the same result can be achieved with pin diameters of 1/3rd of the dovetail depth. Using the correct diameter pin for the correct angle and depth makes cutting the dovetails easier as the measurements for both are the same.
I would have explained it without the 5 '' and carried out the trig to get to the 5'' dimension . The reason is that dimension may be on a print , but not if you have to machine the other matching dovetail to an existing part . Not having a go at you mate , but the dimensions are not always present in the real world . Cheers . .
👍 nicely done as always. Are those geometry principal assigned numbers standard? Or is based on the author? How deep of a cut would be needed per side with the dovetail cutter if you measure .002" undersize? Is it 1:1? So .001" per side? Thanks
An amusing applied math problem (I say that in the singular because it's finding the same general solution, and then either adding it twice or subtracting it twice). As a math rather than a machining person though, I am somewhat baffled by the non-math aspect of this. Why, in a machine shop, would you not just grab calipers or a micrometer and measure the distances marked ? directly? I assumed that the whole point of using dowel pins in a case like this was to allow an easy direct measurement (calipers against dowel pins) and from there calculate a dimension that's very difficult to measure because the overhangs caused by the acute angles interfere with the measuring tools. This example looks backward to me. What am I missing here? Did the trig a bit differently, but in trig there are usually many equivalent options. Distance1 + 2L +2r =x, Distance2 - 2L - 2r = x, theta = interior acute angle spanned by the dowel pin L= (r + (r/cos theta))/ tan theta, r = 1/2 the diameter of the dowel pins. x= the dimension obstructed from direct measurement? by overhangs.
At 4:52 what is 2nd X-1. Mine is EE and all I get is SYNTAX Error ? I already solved the problem by 0.375/tan30= 0.64951 but I would like to know your 2nd function as I'm using a TI 30X iiS
OK never mind, I found my answer. I don't need 2nd F, my X-1 is first. I just could not make out the numbers on your calculator even with a magnifying glass. ps: good lesson, thanks.
What type of calculator are you using I only use sharp calculators Depending on the calculator you may run into problems because Texas instruments don’t work the same as sharp calculators do What type of calculator are you using?
It's the 30X iis. I've got the X-1 function but I don't need to use the 2nd function button to get to it. When you said hit 2nd 1 over that is what I did; that function for me is EE. I made a reply, to my comment, that I figured out what to do with my calculator and thanked you this lesson. I'm just now getting a handle on Sin, Cos & Tan so I'm copying the chart about the other trig functions and this is just just the information I've been looking for so again I'll say thank you Sir for this much need lesson.
Good job
Two thumbs up
thank you for the nice comment
Ray
Thanks for sharing
👍🏻
thank you for commenting
ray
Thank you for taking the time to comment
Ray
Nice, well done. simple and organized.
thank you
Ray
👍👍👍
For a 45 degree dovetail use pins that have a diameter of 41% of the dovetail depth. This way when measuring over the pins in both the male and female parts the dimensions will remain the same.
For 60 degree dovetails the same result can be achieved with pin diameters of 1/3rd of the dovetail depth.
Using the correct diameter pin for the correct angle and depth makes cutting the dovetails easier as the measurements for both are the same.
Thank you for sharing.
And thank you for taking the time to call me. It’s much appreciated.
Ray
Another great video. Thanks for taking the time to explain it in depth...
thank you
Ray
Thanks....I get it now.
I laughed so hard at the introduction to the video, not at your skill level. Good way to kill off the trolls
I wish you were my math teacher in high school, lol
I would have explained it without the 5 '' and carried out the trig to get to the 5'' dimension . The reason is that dimension may be on a print , but not if you have to machine the other matching dovetail to an existing part . Not having a go at you mate , but the dimensions are not always present in the real world . Cheers . .
👍 nicely done as always. Are those geometry principal assigned numbers standard? Or is based on the author?
How deep of a cut would be needed per side with the dovetail cutter if you measure .002" undersize? Is it 1:1? So .001" per side? Thanks
An amusing applied math problem (I say that in the singular because it's finding the same general solution, and then either adding it twice or subtracting it twice).
As a math rather than a machining person though, I am somewhat baffled by the non-math aspect of this. Why, in a machine shop, would you not just grab calipers or a micrometer and measure the distances marked ? directly? I assumed that the whole point of using dowel pins in a case like this was to allow an easy direct measurement (calipers against dowel pins) and from there calculate a dimension that's very difficult to measure because the overhangs caused by the acute angles interfere with the measuring tools. This example looks backward to me. What am I missing here?
Did the trig a bit differently, but in trig there are usually many equivalent options.
Distance1 + 2L +2r =x,
Distance2 - 2L - 2r = x,
theta = interior acute angle spanned by the dowel pin
L= (r + (r/cos theta))/ tan theta,
r = 1/2 the diameter of the dowel pins.
x= the dimension obstructed from direct measurement? by overhangs.
At 4:52 what is 2nd X-1. Mine is EE and all I get is SYNTAX Error ?
I already solved the problem by 0.375/tan30= 0.64951 but I would like to know your 2nd function as I'm using a TI 30X iiS
OK never mind, I found my answer. I don't need 2nd F, my X-1 is first. I just could not make out the numbers on your calculator even with a magnifying glass. ps: good lesson, thanks.
What type of calculator are you using
I only use sharp calculators
Depending on the calculator you may run into problems because Texas instruments don’t work the same as sharp calculators do
What type of calculator are you using?
It's the 30X iis. I've got the X-1 function but I don't need to use the 2nd function button to get to it. When you said hit 2nd 1 over that is what I did; that function for me is EE. I made a reply, to my comment, that I figured out what to do with my calculator and thanked you this lesson. I'm just now getting a handle on Sin, Cos & Tan so I'm copying the chart about the other trig functions and this is just just the information I've been looking for so again I'll say thank you Sir for this much need lesson.
👍🏻
Thanks for the positive feedback
Ray
👍🏻
Thank you