Gear cutting on a Shaper (making the tool)

[Music] hi welcome to my shed my name is paul hopewell firstly i'd like to say thank you to all my subscribers i also want to say to those who've seen my videos for the first time please subscribe and click the bell to get the latest updates and releases today's video is about another experimental project that i've been toying with a while ago i made a eureka relieving tool big enough to work on larger cutters but after seeing a youtube video by a guy from new zealand called jeffrey crocker i decided to take up his challenge his challenge was is there an easier way to make gears on a shaper this is a prototype that's going to use a method to have seen many times on youtube this will have a few changes and i think it'll help i'm going to leave this device open for anyone to copy or modify the requirements are that the device must be able to cut between 10 and 100 teeth on any pcd using minimum tools and it must be fully adjustable and easy to set up all but one i've seen on youtube employ a strong wire supported by a fixed point at each end it's wound over a set pcd roller that in turn manipulates a gear blank under a cutter producing a gear tooth shape my idea is to use a solid bar as a push-pull link to rotate the gear blank about its axis this bar is to be connected to one fixed point on the shaper the other end connected to an adjustable pcd index arm indirectly connected to the gear blank rotation shaft via an index plate unlike an indexing head or table each hole represents a gear tooth not a division of rotation because the number of or the sequence of holes represent a gear tooth i've deduced that i need 50 sets of holes ranging from 51 to 100 holes and i'll explain more later the arm a device that manipulates the gear blank under the cutter is clamped to the indexing plate via a clasp or a clamp that works a bit like a disc caliper on the car's braking system it should easily allow the index plate to be freed indexed and then re-clamped what i'm drawing on the whiteboard is a side view of the index plate and the arm mechanism these rough sketches are my way of working things out and they've always been proven to be most successful why do i need so many index holes i hear you ask an index table uses a set of registrations that is a series of revolutions and added index holes to advance to the next position this isn't the case with the direct indexing system so in order to produce 100 teeth on a gear blank i would need 100 index positions the thing is 100 holes will also cut 50 it'll cut 25 20 and 10 holes and the 51 tooth gear registration will cut well 51 and 17. there are some numbers in the system that will only cut that number like say 71. prime numbers therefore the combination of 51 up to 100 indexing holes will enable the full sequence of 10 to 100 teeth to be formed in order to make sure that such a large number of holes can indeed be cut onto a six inch blank i use the cat package to help me devise a hole pattern to fit on as fewer plates as possible yes i've been delving into jump piles again and this lot is going to have to do i did have to buy seven six inch diameters by six millimeter plates though i suppose that means i've got to go back to eating baked beans for a week or two i suppose here's a tip to mark out on black plate try this little trick grind some chalk stick to a fine powder then add a little methylated spirits just enough to turn it to a paste then brush it onto the black plate and let it dry it doesn't take long then you can mark out and quite clearly see where you've marked here i'm marking out the center hole and marking out for the 40 millimeter three hole pcd this bit of the operation is a bit iffy um but to hold this plate i had to use the four jaw chuck even so each jaw is on its limit whilst clamping this plate each stage of the drilling process takes the ball out to 20 millimeters and from then on i have to use a boring bar to make the whole 25 millimeters diameter this is where i drill the three holes on the 40 millimeter pcd i also recess one side of the three holes to accommodate the counter sink screws to hold the plate true on the index table i'm making an adapter to hold the index plate while i drill all the index holes there's nothing too spectacular about this adapter except that both sides must be parallel to one another it'll have two spigots on it one to neatly and snugly fit into the index table and the other must be a nice firm fit into the index plate at 25 millimeters on the 40 millimeter pcd it also needs the three holes to coincide with the index plate it needs a hole through the center to accommodate the 16 millimeter cap head screw which has been pre-machined to fit into the back of the index table allowing me to tighten everything together without interfering with any other work surfaces this bush will have the job of holding the index plate while it's being drilled and once set and tightened it must never be undone until all of the index holes have been drilled as setting it up again will be quite a complicated process the three holes will allow me to exchange the index plates as and when i require them i have toyed with the idea of offsetting the index holes to these screws to reduce the amount of index holes i have to drill like having a 50 whole set offset by 50 would give me a hundred holes then by offsetting the 50 set hole plate again would still give me the 150 25 20 and 10 holes that i need even so i would still have to make sure that i had the 10 prime numbers so i decided to stick with the 50 sets of index holes to make it easy for me i've still got to drill approximately 3500 holes to complete the index plates it sort of makes me wish i'd got a cnc milling machine before i can drill the holes i need something to drill the holes with namely something to index the holes on the plates and for that i've got two devices a forty to one kearney and trekker dividing head and a ninety to one dividing table i've got to sit down to explain this next bit i use the black book reference section on dividing tables and decided to use the 90 to 1 dividing table to help me drill the index holes now i've got the full complement of indexing plates that came with this 90 to 1 indexing table and to use them to the fullest i still have 25 sets of holes i still cannot do however 8 of those 25 holes can be done on the 40 to 1 dividing head leaving me with 17 sets of holes short that means in order for me to drill the full complement of holds that i require for my index plates i've got to make some index plates for the dividing table so i've decided to make the entire set of index plates for the 90 to 1 dividing table using whatever method i can starting with the plates for these i used a bit of scrap metal and i filled the holes with a bit of weld i already know i can cut eight of the 25 holes using the 40-1 dividing head but the other 17 holes involve me having to use the computer and the cad program again and with a little bit of luck and sticky tape i managed to the remaining 17. yes i literally meant sticky tape and look calculating the amount of holes i needed for these index plates that fit on the dividing table i got the cad program to print these sets of radially lined marking points i use the lines and not dots because when i go to drill the holes i will mark the paper with the drill and then back off to check the mark against each line as i do them this method is not as good as having the index table to accurately position the holes but it is better than no method at all at least in my eyes this system may be one step up from guess work but it is working all the holes i've cut so far are to give me the full range of holes for cutting the holes in the gear index plates so here we are cutting the first set of 100 holes using the 90 to 1 indexing table i'm not going to do the full 3500 holes in one go i'm only cutting the 100 and the 51 set separated by six separate lanes representing six more sets of holes this is the main shaft being roughed out to one inch diameter when it's done it'll have a collar welded to it and the collar will have three holes at 40 pcd tapped at m6 i won't show it being welded on or after it's been welded because i think i've told you in the past that i'm not a welder and my welds look awful after making the collar then drilling it and welding it to the shaft i put it back into the lathe and tidied everything up by machining 0.4 of a mill off down to 25 millimeters i'm going to put a thread on the end of this using my thread cutter and because i'm using a two mil thread i need to put a good thread relief on the back so as not to break the tip with all threads i started with the scratch cut and checked it then proceeded to complete the thread prototype cutter still cuts a nice thread the other end of this indexing shaft i'm putting two spigots one at 20 millimeters the other at 14 millimeters then after cleaning all the dimensions up i've used a couple of my lathe change gears to test the fit there that's good enough i'm drilling the end of the index shaft to take an eight millimeter thread and then i'll relieve the end ten millimeters out to eight and a half mil this will take an eight millimeter by fifty millimeter long cap head screw this eight millimeter screw is going to be used to retain the gear blank so that the screw needs to be a good quality one i only showed you two slots being cut but i actually put four slots on all together on the 20 millimeter diameter i put a six and a five millimeter wide keyway and on the 14 millimeter dimension i put a four and a five millimeter wide keyway on after all i need it to be as universal as possible this is where i make a collection of sleeves and bushes that go together to provide packing and support for the gear blank there's also a couple of items that go to hold the indexing arm in place this will be the knurled hand locking nut that holds and supports the index arm i used a side loading knurling tool to put a grippable surface on the outside edge of this nip knot i don't like using side loading knurling tools so i only used enough surface pressure for a short time to rock the outside edge enabling me to hand tighten it this little bracket is the clamp that provides the movement free indexing transferring motion from the index arm through to the index plate with almost all of the sleeves and bushes completed i've now started work on the main body this is the upright post that will carry the indexing shaft when it's finished but before i weld it to the main base plate i'm going to rough drill and prep it for welding the base plate is being slotted so that it can be bolted to the shaper after prepping for welding i used magnets to keep everything square and used large fillet welds to make it as secure as i possibly could i put a little bit of black paint on just to hide the mess back to the milling machine i'm going to square up both ends of this main body using one side as a as a datum edge before i clamp it to the angle plate i briefly run it on the belt sander to remove any blemishes having done that i could then clean up the front face square to the side face at this stage the front slotted face is true and square to one side only it's square but it's not true to the bottom face and at this moment it doesn't matter so long as i can skim the back face as true to the datum face as i can that's enough cleaning up this back face prepares everything for the next operation putting the back face flat on the machine table and the bottom face square up against the angle plate i can now clean up a small area on the thrust face to give spacers and packers a face that won't distort them out of position mounting the back face on parallels in a milling vise allows me to finish the 25 millimeter bore using the adjustable boring bar this is a snapshot from my cad program showing the elaborate index arm i'd originally planned to machine the component out of one solid piece but as i couldn't find one solid piece i had to make do with welding two pieces together after machining each part first the top piece is the part that allows the pcr to be set the bottom piece is the indexing and clamping component of the arm we'll start with the pcr segment first after marking out the pcr segment it was back to the milling machine to set the center hole and to cut the slot i used a six millimeter four flute cutter to make the slot which is approximately 104.5 millimeters long off camera i also centre drilled the 20 millimeter diameter relief that will have to be hand filed later with making these two pieces i will have to do a lot of hack sawing because my bandsaw is a horizontal gravity fed type powered saw and hasn't the capacity to allow any freehand working this is what the pcr section looked like before it was hand filed and this is the pcr section complete and prepared ready for welding now it's the turn for the index section to have the same treatment and as if by magic here is the complete unit sporting the same 20 millimeter hole as the pcr section before i welded the two parts together i used a bit of 20 millimeter bar to align both of these two parts together after welding the two parts together i clean up the messy bits and i mounted the whole index arm in the milling machine to use the same boring bar to boil the hole through to 25 millimeter so that it slid onto the shaft because it needs to rotate and not grip like i say i'm not proud of the welding but it'll do its job originally it was my plan to use a thin bit of metal to act as a sector arm after a lot of messing about it proved to be a bit too flimsy so after delving into my box of brass bits and bobs i sourced a bit of bar that would make a brass sector arm quite nicely now i have enough components and i'm at the stage where i can at least attempt to make 150 tooth gear like the one you see in the picture if you look at the index arm you'll notice there is a nut and bolt in the slot in the center of the nut and the bolt there's a very small indent this very small punch mark plays a very important part in setting the pcr a corresponding punch mark exists in the end of the indexing shaft i'll explain its function in a moment but first i'll assemble the device the indexing spindle fits into the main body through from the back face the indexing plate is then fitted over the 25 millimeter threaded end and butts up to the receiving face on the spindle flange the three screws can be fitted and nipped up next the index arm is placed over the same end and is pushed up to the index plate the 25 millimeter threaded thumb knot is fitted and is just hand tightened the locking clamp is the next thing to be fitted and for the moment is held in place by one six millimeter hexagon screw turning the unit round all that is required now are a series of collars or packing bushes amongst which one will be the gear blank before finally having the retaining sleeve fitted and held in by one eight millimeter high tensile steel screw this is a shot of the locking clamp and the ground four millimeter dowel that will assist the indexing you'll notice that the sector arm is already set to two spaces here we are with the device bolted to the shaper at last the device is also fitted with a gear blank of 77.9 millimeters diameter in the background you'll notice there's a large section of angle iron it's attached to the shaper's main body temporarily i know but it will change to something that's a bit more usable between it and the indexing arm is the link rod earlier i mentioned a punch mark in the middle of the bolt that is attached to the slot on the indexing arm i also mentioned about the punch mark in the middle of the indexing shaft an important part of making a gear is knowing the pcd the pitch circle diameter divide that by two and the result is the pcr that's the pitch circle radius using a pair of dividers to set the pcr i can set the slider screw to the correct position with the dividers and lock it off with the lock nut you will note that the punch mark on both components are at the same level to help reduce any cumulative errors turning my attention to the cutter it's difficult looking at a gear to determine what the pressure angle is the tool you see now is set to 14.5 degree pa pressure angle and this was pure guesswork to be honest and the flat at the bottom of the tool is 1.6 millimeters wide it roughly fits inside one of the teeth on my 50 tooth gear to be honest the gear was made in china so for all i know somebody could have sat there at a bench and filed it to shape who knows after i had cut the first few teeth i compared my gear with the teeth on the blank and it didn't quite match i then ground another cutter to 20 degrees pressure angle and calculated that the flat on the bottom of the cutter needed to be 1.09 millimeters wide from then on the gear look much much better in the past i've never really had anything to do with making gears for me this is my first foray into making them and it's a bit of a steep learning curve i can thoroughly recommend that before you even venture into making your own gears that use your studies include visiting youtube sites from mr pete 222 and this old tony then getting yourself a book on making gears i can guarantee that you'll find what you're looking for but you will need to work out for yourself how to deal with the many aspects of making gears my way of dealing with the peculiarities of gear making was to make a spreadsheet that calculated and manipulated the information at hand to formulate the important calculations at the moment if i input the outside dimension or the pcd the pressure angle or and the number of teeth the spreadsheet spits out the corrected pcd the outside dimension it repeats the number of teeth the tooth thickness the depth of tooth the width of the cutting point on the tool the mod the dimetal pitch and the root dimensions pretty impressive eh well i think so didn't all go swimmingly either on my first gear the tool moved in the tool holder ruining the blank and i had the wrong pressure angle set also the link rod will need some better bushes made to greatly reduce the amount of backlash within it now all i've got to do is drill the remaining three and a half thousand holes to complete the remaining index plates that's going to be mind numbingly fun that said my first complete gear was a total success i hope you enjoyed the video thank you for watching bye for now [Music] you

Channel: The shed dweller

Views: 131,358

Rating: 4.8687615 out of 5

Keywords: Shaper, gear cutting on a shaper, gear cutting, gears, shaping, shaper gears, involute gears, involute, gear cutter tools, gear tools, gear device, cutting gears, cutting involute gears, cutting gears on the shaper, spur gears, cutting spur gears on a shaper, spur gears on the shaper, involute spur gears, cutting spur gears

Id: 7De17gyX2sU

Length: 29min 29sec (1769 seconds)

Published: Sun Aug 16 2020