40+ years as a toolmaker and here I sit rapt in class.........and no place I'd rather be. This man is a true teacher, and an instrument of God's good works.
Well Lyle, you have just proved to yourself the inaccuracies of using transfer punches that I have in the past kept telling you about. The punch marks move plus any drill wander give you inaccuracies. You already had a drill jig in the form of the master plate. With it clamped you could have spotted through every hole with a close fitting drill, seperate the plates then open up your new plate to eight inch. Would have then been as good as your Hardinge plate. In my 50 plus Years of engineering here in England I have never seen let alone used transfer punches. Must be an American idea, I see other USA people on RU-vid using them. Please remember, spotting through a part you already have will always be more accurate than marking and centre punching.
@@donnerpartysupplies5187 Now you can use your half plate to make a new one, by simply transferring the good sections of hole ring by ring onto a new plate, just select a single line to be the new reference line for the new plate, as they otherwise will be all over the place.
@@donnerpartysupplies5187 You can do it with just a drill press, and a dowel pin, plus a centre mandrel to follow the inner centre closely. Just means you will be doing a few trips around the plate per diameter stepping out each time from your initial row of holes. No DRO needed, nothing complex, and should be accurate enough so long as your half plate has at least a third of the area. as you will be tossing it afterwards no need for transfer punching anyway except for the initial set of holes, to get them all in a line, if the plate does not have that aligning point. Just going to need you to have a set of new drill bits that accurately match the existing holes, they will serve as transfer punch anyway, and with cast iron should not damage the hole too much during the 3 or 4 drill passes per hole.
This was very good Lyle - Thank you. It may well have been that the poor bugger who originally made these with drafting equipment & calculator was the same man who invented optical center punches - before he went mad.....
Keith Rucker showed me what they are used for. He also said that using a torch was way faster and less tedious when cutting them, just as you did in that first video! Proves you're still the Master! :-)
G'day Tubalcain. I've been at a bit of a loose end since you stopped advising us which tools to buy, and how often, at the end of your videos. But now you've given us some direction again - "one of every tool known to mankind". Works for me!! Compliments of the season.
The versamill was made in at least two sizes. I have the smaller one mounted on old belt drive BS horizontal mill so I can use as a verticle mill also. I watch all of your videos and have learned more than in any shop class!
“Just like downtown”... wow I haven’t heard that since my first shop boss retired twelve years ago. Thanks for the memory and a Merry Christmas to you and your family.
Evidently you haven’t priced unmolested Hardinge attachments. I wouldn’t drill anything Hardinge. Besides, if he took the easy way out every project, there would be no videos to watch.
Loved the video! I nearly shot hot coffee out my nose when you said " if the lathe were to be powerd on, it would kill you!" I could see you in shop class talking to 20 or so hard headed teenagers that can't be expected to under stand, unless told specifically what will happen! Great series.
You are exactly right that this along with a versa mill would have been found on a submarine. I remember a time onboard the USS Henry Clay SSBN625 in the mid 1980's our ships machinist doing a little showing off with his. During inspections it was not uncommon for the inspectors to bring along a blueprint for a part and expect the machinist to complete it over the next 2 days. The results of these inspections was shared with all the subs so we could learn from each other's mistakes and short comings. We had gotten the result of an inspection where they had been unable to make the part asked because some tool or part of a tool was missing or broken on another sub. Our Captain came to our machinist asking him if we were asked to make a part that we would have everything needed to do it and he assured him we could. He decided to show the captain what he could do, so he took a piece of 4" brass round stock and cut on it, a gear, a taper, right hand v threads, left hand square threads, woodruff and square key slots. Polished it up and made a little stand for it and presented it to the captain. It was quite impressive for our little lathe and versa mill. When the inspectors came aboard that little shaft sat prominently in the middle of the wardroom table. Needless to say they didn't ask our ships machinist to make anything more. He was quite talented and made a number of things over the years such as complicated aluminum hydraulic valve bodies when we had one crack.
That is quite a story. And I’m so glad that you posted it. I hope that lots of people read that. And it validates what I said in the video. I only wish that I had bought that versa Mill at the auction
The versa mill is still taught to machinists mates to be a "machine tool operator" like you mentioned for underway emergency repairs. I was lucky enough to be selected to be sent to the schooling, which actually led me try to learn more about machining and lead me to this channel years ago. I never had to make any repair parts, but along with our welders we made special tools, and I would make parts drawings and try to make them to practice when in port. USS HAWAII SSN-776 From what I could see it looked like the attachment that was on the one at auction was one you could broach or cut internal keyways with. They have a few different interchangeable heads to allow you to do different operations.
Nice one Mr. Pete it is clear that you really enjoy making these videos, and VERY clear that we love seeing them. As long as this does not change, keep at it, and keep going to the auctions, they are good fun for you and ALL of us too. Merry Christmas to you and your family!!!
You can lay out a dividing plate using only a set of dividers. (I guess that name actually makes a lot of sense!) clickspring has a great video about it
Re: accuracy of the spacing... Remember that two things help here- there is no CUMULATIVE error during use, and the ACTUAL error on each hole position is reduced by the work gearing factor (usually 40). Question: Do you have a setup to drill on the Atlas lathe using the 60 hole index built in? That is yet another way to do this.
That would be a very simple and convenient way to do the intended operation of putting 20 divisions on that teaching aid. With no dividing head needed.
And furthermore, when you're using the 'spider' and reduction gear, and turning to every sixth hole in turn, for example, then the inconsistencies between adjacent holes will be averaged out.
@@stevewilliams587 Imagine that there are only two holes in the plate, nominally 180 degrees apart. In actuality, one of the holes is off by 2/3 of a degree (40 minutes) On the plate, the spacing is 179-20' and 180-40'. Ideally, the spindle will rotate 1/80th of a revolution (4-30') when traversing from one hole to the other. Due to the error, the actual rotation will be 4-29' or 4-31', as the 40-1 gearing reduces the rotation of the spindle relative to the crank by a factor of 40, and the error by the same factor (presuming a perfect worm and worm gear, of course). The error will again be 1' for a spindle rotation of 13-30' (1-1/2 rotations of the crank), and so on, as the error for a complete rotation of the crank is theoretically zero (actually controlled by the worm and worm gear accuracy)
Much simpler method. Measure from left edge of one hole to left edge of other hole to give centre to centre distance then divide by 0.8663 to give Diameter of pitch circle. If no calc available draw a line from one center to another, distance from line to third center is 3/4 or 75% of Diameter of pitch circle for three holes. Other odd holes see ZEUS book which gives 5,6, 7,8,9,10,11,12 hole spacings.
I just bought one of these and it only came with one plate. I don't know if I will really use it or not but I do have a headstock that I could attach it to and use it on the mill as a dividing head although with no angle feature.
Sir, may i make some suggestions? I think the first plate should be checking out all the gears in your lathe and mark it in the same plate, and the second plate obviously should be for your milling machine, etc etc. To accommodate the “just in case” no supply of gears situation. And, since it is for index purpose, not hugh force will be apply to the plate, i wonder.....how about 3d print these plates? Nowadays 3d printer are more easy to find than making 3/4 inch steel plates. You can also add one more episode to try one, cut the corners and let the machine doing the bean counting job while you are having a good ☕ of coffee 😎
This dividing head has seen some use...I was thinking this was just some gimmick...but, looking at the wear in the sector square seating slot and the boogered up screws shows use...I can see this being used in navy applications.
Would have to make a new drive or put in a new pin for the selector though, but yes would work. I suspect those original plates were made by somebody making a master plate out of tool steel, and getting all the holes in place with some dividers and scribing, plus a protractor for the angles, then drilling them. Harden the plate, then you simply have a whole stack of the production plates ready, all with the centre hole bored out, and then clamp the whole lot down, and run a drill press to transfer the holes through. Production plate probably was used till it was well wallered out, and then they would make a new one. Gets the precision work out to a single toolmaker, and then Rosie the riveter could turn out a hundred of these in a single shift, and then next day do the same for a hundred of the next size, so after a week you have 100 of the dividing heads for the order, using only a small crew doing separate functions to a set plan. Hard to think that tool making is an assembly line operation, as normally the tools are doing the assembly line work, but here you are using then to assemble tooling.
@@LambertZero Don't think it is that tapered, will be a nasty thing to snag it in a hole and snap off half the pin by accident with the leverage on only a small section of pin and the tip of the hole. you could run a taper reamer through the holes after manufacture to define a small taper on the top to aid alignment, and keep a tight diameter tolerance though, only going in to around a quarter of the plate thickness.
@@SeanBZA The idea is that the pin is more tapered than the hole, so it doesn't lock in there and only makes contacts on the very edge of the hole. I think Stefan Gotteswinter talked about it recently.
@@SeanBZA My shop regularly did that sort of thing. The Item you mention was called a drill jig. I had a production screw machine shop for 50 years. JIM
You asked why no one liked . your program on the Tree D printer , the truth it it smacks of the loss of skills . & the death of the skills we need to hold on to . this is especially , required of the manual lathe. Hears a little History lesson . of the Tolpodal matters , Dorset England . check it out on you tube , That lead to the wavers rioting in what was to beginning of the start of the industrial revolution. the Tolpodal Matras. where deputed for forming the first union , & The weaver smash the loomed because it stole there job's as the industrial mill develop . this is why interest in new Teac is slow to be excepted ,
In your free time, you could make spaghetti! Thanks for class...interesting...I wonder if that Master dividing head was used in the aircraft industry in KS....
Mr Pete, quick question here: if I cut a bolt head down to a point on the lathe and harden it, would this be a good enough transfer screw?? I would have to mill a hex on the tip of course, but I must try. I have read your book about tempering. Now is a better time than ever to practice! Any insight will be highly valued.
Yes I think that would work although it’s tedious. I did not write the books. That was a deceased man from England, he was a professor, and he was brilliant unlike me
@@mrpete222 I had no idea there would be more than one Tubal Cain, writing about engineering... I was referring to "Hardening, tempering, and heat treatment", number 1 of the 'Workshop practice series', published by Special Interest Model Books... It makes no matter. You most certainly are a brilliant man, Mr Pete. You too, are worthy of being called professor. Thank you, for going through the trouble of producing your brilliant videos. They are truly fantastic, and highly inspiring. Like many other viewers I am sure, I look up to you as some sort of a reference: whenever I get stumped on one of many engineering projects that I have going on, I think 'How would Mr Pete go about this situation?' I look up your workshop videos and so far, have always found answers to all of my questions. That, Mr Pete, is quite extraordinary. Out of all the engineering RU-vid channels out there, yours is most definitely the most extensive, accurate, and diverse source of knowledge. You are truly, one of a kind. Thanks a million.
Hello my RU-vid shop teacher, could you tell me what brand of micro drill presses where the cadillac standard of quality back in the day ??? What were they mostly used for also ??? Thanks a bunch and Happy Holidays to you Sir too.
Why don't you get someone to help you with your video? You've got confections to the high school, and maybe the college. But I'm sure someone can help you so you don't need to film your computer/phone screen and print out pieces of paper to film. I'm sure there's some kids that would be dying to do some actual work.
A quick google search turned up several programs to print bolt circles and circles with equal spaced holes. Use one of the to laser print a pattern, glue it to a plate and transfer punch the holes. It should be accurate enough and you don't have to try and borrow a plate.
@@mrpete222 Lyle, I found this. If you look carefully, it has a dividing plate mode. Also, read the whole page. You're welcome. Stan. woodgears.ca/gear_cutting/template.html Sorry, didn't know how to link, so I just copied address verbatim from Chrome browser. Will it help?
Lyle, this is another interesting video. I don't have access to dividing head plates, so I'm also looking forward to your follow-on videos in this series. I've read an explanation on how the "gear ratio" in the dividing head (or geared rotary table?) reduces the errors from the initial "home-made master plate" to the manufactured plate, but don't recall the details. Could you cover that, either in this series or in a later video? I'm going to have to start from _scratch_ when I build my dividing head, with the only "store-bought" parts being the worm & worm gear, fasteners, & dowels. I'll have to start with laying out the hole patterns and go through a few generations of plates to end up with plates as accurate as I can reasonably build them. I'm _really_ looking forward to the ideas & tips you show us!
I did the same test on a dividing plate many years ago to prove an inaccuracy and got the same reckoning. So, one could make his own dividing plate by using close-up vision and accurate marking-out. How close can I get? well, I have seen a clockmaker make one to divide a clock gear blank and if he can do that accurately, then I am sure I can as well. It's all about patience and accurately making the punches to do the job. I believe that if you are going to sharpen a punch, it must be machined ground so it does not warp or deviate the hole because a drill bit to follow will deviate within the punched hole beside the hole not being punched on centre. A close tolerance I believe, can be achieved. Have you carried out this method I talked about here yet? This subject always fascinates me.
A friend of mine has an x British navy lathe, it has a milling machine on it, it’s like an all in one type thing, perhaps that dividing head’s for something like that.?
This dividing head is an accessory for the master mill which was commonly used on US subs. The master mill mounts in place of the compound. With the master mill on the compound and this head on the spindle one can cut gears etc. I happened to get a master mill with my sidney cone head lathe but did not get the dividing head.
Oh sorry do I have the wrong person the toolpost kit is for sale at Hemingway kits under tool holding for myford lathes. It was design by a man by the name tubalcain
fantastic video, I have only 2 plates with my dividing head that I found in the trash bin. And always thought if I needed a special number divisions I would just make one on the mill with the DRO bolt circle feature.
I use a divider head all the time; but I use it on my wood lathe and realize the many uses for it. I use the dividing head to make basket illusion bowls and platters out of wood. You might want to do a Google search for "basket illusion bowls" to see the end results of what I do with the dividing head. My lathe is a Powermatic 4224 B and it comes with a dividing head built in it. I enjoy your videos greatly and met you out at the Summer Bash.
Our "Mr Pete" is dazzling us agin, aint he! Cuz he 'jes caint hepit". But none better. Again, and again, we are blessed to have "Mr Pete" to teach us; in a way that makes it fun. We luvs yuz Lyle. We shonuf does.
You could have made the 15 hole plate while set up in the lathe as the tool was intended along with a tool post mounted drill. 40/15 = 8/3 = 2-2/3 so 2 turns+22 holes on the 33 hole circle. Physician heal thyself.
This will be a nice series that we will all enjoy watching, but certainly you must have considered just drilling the Hardinge bolt circle into the indexing head so you could mount your Hardinge plates, right??
A cheap way of dividing is to go to the farm supply store and get a sprocket, they are sold in many sized with many different tooth counts. I mount it to an expanding mandrel in the lathe spindle and make some sort of detention to hold the sprocket in position. A 60 tooth sprocket will give many combinations of spacing. And save a lot of time and work.
great struff Thanks Lyle, now I have proper authorzation to buy more tools just incase I need them :D , I know what you mean, I bought an inside and outside CIR clip set about 4 years ago, wondered why I bought them, last week I needed to use one of them ;) , the £10 investment paid for itself years later, now I need to go out and buy 10x 17mm and 19mm spanners and 20 scribers.. then scatter them around the workshop so when I forget where I put the one I had in my hand secpnds ago I know there is another one nearby... somewhere
As much garbage is on RU-vid, it is awesome someone like mrpete can pass on the wealth of knowledge he has to thousands of people all over the world. There are good parts of RU-vid and this channel is indeed one of them.
I was hired once, to make 8 plastic disks for lapping which had 211 holes each. My boss was in a pinch so I told him I'd do it. I made a template out of thin plywood and drew it out on a drafting table. I won't go into the whole process but I ended up making about $8 an hour by the time I was done. I told him I could only guarantee about 1/4 of a millimeter accuracy. This was before I was a machinist otherwise I would have told him +/-.010" . I was kinda proud of being able to keep that tolerance with a drill press & a drafting table. The blueprint called for +/- .005 but the client didn't send them back so I guess they worked. Come to think of it, it was that job that lead a chain of event that eventually ended with me finishing manual & cnc machining courses.
If you were going to make a plate with the most commonly needed divisions, which numbers of holes do you think is most useful? I was thinking 18 and 25 would cover almost everything, because 18 gets you half degree increments, and 25 gets you 1/1000 of a circle. In terms of prime factors, you get 2*2*2*5 from the gear reduction, 18 is 3*3*2, and 25 is 5*5. After those two, maybe 21, 33, 39 and 45. Though perhaps it's a better idea to just wait until you need to make something with a division you don't have.
@@mrpete222 I know there's a lot that you can't get with the set I listed, like primes 17 and up, powers of two 32 and up, powers of three 27 and up, etc. I think I'd only make a 15 hole plate if I needed something like 75 divisions. To get 1/25 I'd just make a 5 hole plate, and leave the option open to make it a 25 hole plate later (for example if you want to add a vernier, I think that would need a 25 hole plate, for 11/250).
Lyle I would loved to have had you for my shop teacher but I'm only a couple years younger than you so it could not have been possible. I now have you as my RU-vid shop teacher and I'm learning something new with every video. Thank you for sharing your vast knowledge with the world.
I did not read all the comments here, so maybe you all will forgive me for repeating. I visited an old, shut down machine shop in Dalton, Ga. once where I purchased several pieces of equipment. One piece I would have liked to have bought was a lathe capable of 240" between centers. The problem I had with it was the swing was just too small for that length. I'm not sure I it would have swung 12" pipe. Which is a common size for rollers here in carpet country. But, I digress. This lathe had a couple shop built attachments. One was a shelf of sorts at the headstock which adapted an indexing head to the outboard end of the spindle. The other was a milling attachment that rode on the tool post carriage. I was able to figure out this setup was used to machine extruder screws/augers with multiple start threads. There were several of these lying in the warehouse which looked to be about 8 inches in diameter by about 16 feet in length. Some even had variable pitches. Not sure how they pulled off the transition from one pitch to the next though.
I've been watching your channel for a while now and really like the content. I wish I would have had a shop teacher with your knowledge and teaching skills when I was in school.
"No one in the free world needs to make plates like this" Um, i, uh, I actually need to make plates like this lol. However, i do not have a plate from which to copy. If i did, i suspect i wouldn't need to make the plates. ;)
I have what I believe is part of an indexing assembly for a Rivett lathe. The cutter is held in the lathe chuck while the work (gears primarily) are held in a 4OS collet. The index plate has notches (like teeth) around the OD of the plate instead of holes, and there is a simple spring loaded, toothed lever that locates the notches.
If you were going to create a dividing head plate from scratch on a rotary table and accuracy was paramount, you would want to use the largest practical radius for the holes, correct?
I have a rotatory table with a 90 to 1 ratio. I have only one index plate with it. I want to make the complete set. I have the 15, 16, 17, 18, 19, 20, 21plate, are all the other plates the same regardless of the gear ratio?
Probably getting too smart for my own good, but would it make sense to transfer the mounting screw holes to the blank. Then drill and thread them and use them to keep the master plate from moving? Yeah I know 9 or more ways to skin the wildcat.
Does anyone know of a tool or concept that could be used for Very light lathe work on a mill? I need to cut a precise 67.5° angle in 5/8” SS, and ideally need a device that will allow me controlled freedom of motion along an axis at a adjustable angle. Hopefully holding a standard insert and being able to restrain the device in a vice or on the table. Essentially the tool holder on a lathe but able to be used on a mill... has anyone done something similar and can advise. Believe me, I want a lathe and he room to place one, but have 8 parts I need ASAP. The mill does not have a adjustable angle for the head, restricted to Orthagonal movement.
You could actually make more precise plates by using the index head. Just stick your inacurate plate on there, put a raw plate in the chuck and index it for drilling. Because you have a gear reduction, you also reduce the error. You could then put that plate onto the indexer and make an even more accurate plate, and continue infinitely. Of course at one point it wouldn't be practically possible to get more accurate, but it brings you really close.
Just to expound on the point Mr. Pete made about variation in the hole positions not being extremely critical to a useful index plate. The table below shows that even if the dividing plate holes were drilled on whole-degree positions, the error in the final position of the feature (hole, gear tooth, slot, etc.) on the work piece being divided using the plate is very small because of the worm reduction. The maximum error in the work piece would be 36 arc-seconds! For most work that likely would be acceptable. If needed, a second, more accurate, plate could be made using the first plate. Assuming a 40:1 reduction, the error in the second plate would be reduced by 40. The result equates to about a half-thou on a six-inch diameter. That would be pretty tight tolerance to try to hold on a thirty or forty-year old manual machine. Using the whole-degree scheme, a spin indexer could be used to quickly create a special dividing plate for a rotary table. Of course, using the rotary table and just setting to the nearest one-half degree using the table's scale and a worksheet with the calculations for the degree setting for the desired number of holes would result in an even more accurate indexing plate. Plate hole Angle A Hole No B Angle C Nearest whole degree D "Error [decimal degrees]" Error in: E Dividing Plate Hole spacing [DMS] F work piece using 40:1 worm to index [DMS] A B C D E F 1 14.4° 14.0° -0.4° -0° 24' 0.0" -0° 00' 36.0" 2 28.8° 29.0° +0.2° +0° 12' 0.0" +0° 00' 18.0" 3 43.2° 43.0° -0.2° -0° 12' 0.0" -0° 00' 18.0" 4 57.6° 58.0° +0.4° +0° 24' 0.0" +0° 00' 36.0" 5 72.0° 72.0° +0.0° +0° 00' 0.0" +0° 00' 00.0" 6 86.4° 86.0° -0.4° -0° 24' 0.0" -0° 00' 36.0" 7 100.8° 101.0° +0.2° +0° 12' 0.0" +0° 00' 18.0" 8 115.2° 115.0° -0.2° -0° 12' 0.0" -0° 00' 18.0" 9 129.6° 130.0° +0.4° +0° 24' 0.0" +0° 00' 36.0" 10 144.0° 144.0° +0.0° +0° 00' 0.0" +0° 00' 00.0" 11 158.4° 158.0° -0.4° -0° 24' 0.0" -0° 00' 36.0" 12 172.8° 173.0° +0.2° +0° 12' 0.0" +0° 00' 18.0" 13 187.2° 187.0° -0.2° -0° 12' 0.0" -0° 00' 18.0" 14 201.6° 202.0° +0.4° +0° 24' 0.0" +0° 00' 36.0" 15 216.0° 216.0° +0.0° +0° 00' 0.0" +0° 00' 00.0" 16 230.4° 230.0° -0.4° -0° 24' 0.0" -0° 00' 36.0" 17 244.8° 245.0° +0.2° +0° 12' 0.0" +0° 00' 18.0" 18 259.2° 259.0° -0.2° -0° 12' 0.0" -0° 00' 18.0" 19 273.6° 274.0° +0.4° +0° 24' 0.0" +0° 00' 36.0" 20 288.0° 288.0° +0.0° +0° 00' 0.0" +0° 00' 00.0" 21 302.4° 302.0° -0.4° -0° 24' 0.0" -0° 00' 36.0" 22 316.8° 317.0° +0.2° +0° 12' 0.0" +0° 00' 18.0" 23 331.2° 331.0° -0.2° -0° 12' 0.0" -0° 00' 18.0" 24 345.6° 346.0° +0.4° +0° 24' 0.0" +0° 00' 36.0" 25 360.0° 360.0° +0.0° +0° 00' 0.0" +0° 00' 00.0"
Wow that is great information. And you certainly did expound. I hope lots of people read your comment. Thank you for going to the work of making your comment
Just like Downtown reminds me of the song downtown and when I was just old enough to walk and my Grandparents lived in Sioux City IA and we would walk down to the Kreskee ? store that later became the K-mart stores
I have just seen a video on the Post-apocalyptic inventor from Germany. He has a Metabo system, which is the similar idea. His ran offa drill. There were attachments to make it into a lathe, saw, router and so on. It still works.
Would the " easiest, most accurate" method be to establish OD and ID on a lathe, then use a rotary table on a mill, 1/4 inch end mill every 120 degrees on the mount screws circle, then 1/8 end mill every 24 degrees on your dividing circle?
you can take a small v block and turn it on its side and put your punch in the v to hold it at right angles to the plate. you can hold them together with one hand
Is there a reason you removed the spider in three pieces? It very much looks like all three pieces could have been removed together as it is free to spin and the tiny screw just lock the three pieces together once set for use.
THANK YOU Mr PETE. NICE VIDO, LOOKING FORWARD TO THE NEXT ONES. YOU DO RAMBEL ON A BIT BUT IT IS IMPORTENT TO MAKE SURE YOU GET THE POINT OVER. REGARDS RICHARD in U.K..
It would not be too difficult if you had a dial on the handle of a dividing head. A typical dividing head is a (40:1) ratio which is 9 degrees every rotation. For example if you wanted to make a hole every 36 degrees... 10 holes in a circle... you know that 36/9 is 4... so drill, rotate the handle 4 times, drill again. Even something like 7 holes which does not divide evenly... 360/7 = 51.4286 degrees... so divide by 9 and get 5.7142 rotations. If the dial was marked in 100 increments you get as close to 71.42 as you can. I would think the backlash would be more than the human error... and you would still end up +/- 1/100 a degree.
@askjerry if you want 10 holes there's no need to convert to degrees, just divide the gear reduction by number of holes to get your number of turns. As for dividing by 7 manually, that would work, but it would be a lot slower than using a plate.
@@sleepib The discussion is how to make the original plate for production... If you already had a plate, then why would you not use it? We are discussing the HOW the original plates were likely made.
@@Askjerry Sorry, I misunderstood you. There are a whole lot of options for making the first plate, depending on what you have access to. The lowest tech option might be a compass, step around the circumference and make small adjustments until you get back to the starting in the desired number of steps.
@@sleepib While that sounds like a good solution, consider some of the discs with a larger number of holes such as 72 for example. (5 degrees apart.) How would you start? And as you subdivide each section, any error is exasperated and becomes larger with each iteration. using a geared index, if you start at the same spot each time, any errors are limited to less than 1/100 degree, and any errors are not additive for each successive division. That's what makes it an interesting problem... they had to do it where as much accuracy as possible is maintained. Using a 40:1 gear ratio, you simply rotate the crank a total of 1.8 rotations per division. Imagine a disk on the crank with only 10 marks... for a 40:1 gear ratio, that means you have a resolution of 400:1 or better than 1 degree of accuracy. With 100 evenly spaced marks... that is a 4000:1 accuracy. Of course... your method could be used for the initial 100 marks... as afterward any errors would only contribute a small amount to any single division.
That's it! After months of pure delight of listening to your videos and wise and fair words of advice, not only in regards to tools and things, but also about manners and posture towards life, I hear your words of advice and my hope is that all men could listen: "I implore you, buy yourself hundreds of tools so you have one of every tool ever known to manking." Thank you Mr. Pete, I wish I could have met your videos when I was in my teen years, but am eternally glad to know you now and will always listen and learn from you.
Gears and dividing heads are always great subjects. Clicksping showed dividing a large plate with dividers and marking out accurately and drilling to make a master holes plate. I like your explanation that any errors are reduced by 40:1 reduction.
You mention getting the "First" might be tricky, and wondering. I'm thinking the answer is basically Sine Bar. Arbitrarily accurate depending on size alone to crush problems. Glue plate to large (8+feet) table. (countersinking if needed) Drill/Ream long straghtedge *and* plate *and* table. Pin in that hole. Drill/ream ruler and table at other end. pin in table. pin-punch in ruler end. "Baseline established." Oh, no. Math. How far apart should these two pins be for (1/15) of a circle. Math says "x inches!" Measure ... punch. Since the straight edge is -straight-, the extremely large circle's 1/15th can be transferred to the little circle of the dividing plate. Both the more-accurate "calculate each hole independently!" and the "just use the new hole as the new baseline and calculate 1/15th again" methods can be used from there.
Simplish Method For making plates described by gingery in machine shop from scrap... . Measuring tape... Doesn't matter what size/divisions so long as accurate... Say it's 1mm graduations... If you wanted 360 marks to a rotation... Turn a disk so circumference is 360mm, then wrap tape around circumference, and each tape mark will define the 1/360 of rotation. If you wanted 99 divisions... turn cylinder to circumference of 99 etc. Possible to use right angle triangle to "drop perpendiculars" and scale a tape's indii up/drop to suit different circumferences, but that would get tedious... Custom index tapes can made with a laser printer these days.
Great video. Always takes me down memory lane listening to you it's like being back at Technical collage. All of a Sudan I'm back in the '80s. :) Merry Christmas to you and your family.
Hi Mr Pete! Thanks for all your videos! I built the Gingery lathes years ago and use it all the time. I wanted to add back gears. I had a dividing head with only one plate. I tried generating a missing plate using Gingerys method of dropping parallel lines. The divided strip of paper was taped around the one plate I had and a pointer told me when to stop and drill. I was as careful as I could be using a spotting drill,reamers and all. I even made duplicate plates thinking the small errors would diminish. My one factory plates hole spacings are perfect. I always had .010" errors in mine. My tools are a lot of junk and I'm not sure if I tried again if I could do any better. There, I got that off my chest.
I had the same dividing head using it on my South Bend Heavy10. Although there are many uses for it on the lathe, I found it very useful and easy to make graduated dials. Used along with a four position carriage stop made fast work of the dials.
Just got my first metal lathe at 58 years old. Wish I had gone ahead and done it sooner. Your videos have been so helpful. I have always said no "real" teacher can retire b/c teaching is their nature and not their profession. You teach understanding and do it wisely. I, too, never worked a day in my life. I was teaching science and math in Christian schools during a 20 year paid vacation before health issues made it impossible to be in the classroom anymore. Merry Christmas to you and yours and God bless you for your sharing and wisdom...its a gift.
Thank you very much for that wonderful comment. And I know the teachers and Christian schools are Grossly underpaid. I have a Niece The teachers in a Christian school, she is always struggling financially
dear mr pete, first of all love your videos sir a great honour watching them, i was wondering if you had a video on your gibraltar toolpost as i have a myford super 7 lathe that needs major help on the compound. i dont know how else to contact you so i will stay tuned thanks again
I, for one, am glad that you go into the extra detail. Having a second way to look at things, or just an extra few seconds for the information to penetrate my thick skull, is perfect for me. Also your mention of how the 40:1 attenuates any inaccuracies in the plates makes perfect sense to me. Thanks again. I really wish I had a teacher like you when I was a kid, and I'm grateful to have found your videos now.
Thanks again Mr. Pete , one never stops learning . Maybe in the future make some sectors arms so I can learn how to make some for my dividing head . Thanks
