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Bushings and Gears: The Prequel

Bushings and Gears: The Prequel
so I got it in my head to build something but I'm not gonna tell you what it is call me old-fashioned behind the times stubborn stuck in a rut whatever you'd like but as with most things I built I like to use parts and I'm gonna need some parts to build my thing this video will be about some of those parts I'm going to need some

gears

not these

gears

these are just deers a head laying around that I hoped I could make work but I can't I don't really have them in the right
bushings and gears the prequel
sizes these frankly are just props so you're not sitting there staring at me holding a pencil or calipers or something machinist II as with most things that use

gears

the size and number of

gears

in large part dictate what that thing will look like how big it is where other parts will go etc in a way one could say the

gears

drive the design roughly I know what

gears

I want for this thing that I'll be building and seeing that it's the future and all I was simply going to order them
but two things stop me from doing that first I'm a big fan of immediate gratification I want the

gears

right now and second I realized I already have the

gears

that I need they're just trapped inside this piece of cold-rolled steel can you hear that in the famous words of Michelangelo we need only break enough and mills to set them free so here it is in the CNC router I'd like to draw your attention to that hole that wasn't there a moment ago the purpose of that hole will become
apparent when this thing starts milling but I found for my router specifically in steel it doesn't like plunging end mills especially not small ones since this is a high speed spindle I need to use small end mills and small end mills like to brake at the slightest of excuses when I can't come in from outside the stock sort of tangentially I've taken to drilling these entry holes and that one there is located between two of the

gears

in this case the center of that hole consequently
is also the origin of my g-code anyway cue the music now what you're seeing here isn't exactly conventional in fact it might just be illegal and probably immoral these

gears

I mean aren't conventional

gears

the drill is cutting out material that will become the root of each tooth this saves me the headache of using an even smaller end mill to get in there to create a proper gear tooth profile this would be unacceptable for real

gears

but for what I'm making should be just fine
which takes us to the milling this is a 5/32 - flute carbide end mill doing 9,000 rpm and if I'm not mistaken about eight inches per minute step-down is six teeth out the 5/32 mill gets just shy of the root it's too big to get into the bottom and fully form these teeth not counting the drilling operation I'm doing this with two tool paths the first one is doing multiple depths and is leaving 10,000 in space the larger gear has four and the smaller has three the second tool path is a
bushings and gears the prequel
finishing operation at full depth using the same end mill I made three

gears

in total 222 thand 110 tooth these are spur

gears

pretty vanilla really and they started life off in cad with your standard in bluetooth form i mess with the form a bit to make milling on a router easier for me you can probably tell just by looking at them that they're well special nonetheless these are 8 pitch

gears

that's the size effectively and they're 23 degree pressure angle none of that really matters
for what i'm doing and the pressure angle is a bit of a strange one usually you'd see say fourteen and a half degree or twenty degrees the larger pressure angle gives me more space at the bottom at the root of the tooth which was my main concern because of what i mentioned earlier at the router not wanting to route steel with needle-like and mills consequently larger angles also lead to stronger teeth so more load carrying capacity which is good in my case but the operation of the gear
set won't be as smooth and they'll have a little bit more backlash or lots of lost motion between meshing

gears

which again for this particular application are trade-offs i was willing to make so all i did was really wire brush these right off the machine they feel I don't know relatively decent I'm gonna give him a couple of licks with a file right where the 2d milling tool path hit the drilled hole I don't know if you could tell but there's a little bit of a sharp the
teeth look a bit like arrowheads I did have a bit of a hiccup with one of these I had a bad start with the g-code I forgot to rezero my origin for the single gear and it managed to drill a hole before I could stop it i reesy road and started it again thinking what are the odds that that drilled hole is going to hit one of my teeth and by the looks of it I should start playing the lotto a little more often that managed to get pretty deep before I could stop it but it didn't break through to
the other side now this larger spur gear took about 25-30 minutes start to finish so instead of cutting another one I think I'm just gonna fill that in with some TIG weld and file the tooth back to form well when it comes to CNC routing I suppose the old adage is true you take the good you take the bad you take them both and there you have the facts of being wholly impartial that they it's safe for me to say that these are some of the best-looking

gears

I've ever seen next up
bushings and gears the prequel
I've got some honey bunches of

bushings

to make this is bearing bronze its head over to the lathe I've got half a dozen of these to make that'd be 0.5 dozen for the metric crab and then one oddball bushing which we'll talk about once I've made it so I'm gonna truck through these pretty fast without much fanfare they're quite simple really the only point of note perhaps is that I'll be running the lathe backwards well not backwards but spinning away from me for
that to work since I'm still cutting on my side of the stock I've flipped the tool upside down see bronze and brass have a nasty habit of throwing very fine splintery chips all over the place turning my cutting tool upside down and running the lathe backwards hopefully shoots all those chips down into the chip tray and with any luck not straight into my eyes here are six regular

bushings

I suppose these technically be called flanged

bushings

maybe thrust

bushings

I don't know but six
conventional and the seventh is the oddball I think I mentioned earlier we'll have a better look at why this looks the way it does when I put these parts together but for now suffice it to say that when you see parts like this unusual unconventional parts nine times out of ten it's a sign of a lazy design whoever engineered this momentarily fell asleep at the wheel lucky for me they don't ticket hobby machinists for weaving so seven

bushings

and three

gears

I was gonna end this video
here but seeing as I knock these out in less than 10 minutes let's keep going just a little bit further to mount all of these parts I'm going to need three short I'm doing this in a collet Chuck to help maintain the concentricity between the two ends of the stub shafts basically because I have to flip the part frankly for what I'm doing it's not that big of a deal the tolerances I would have gotten out of my three jaw would have probably been fine but forced to have it I
guess so this shaft II just saw me make will be the high speed drive it can be driven from both ends and it takes the smallest gear now the larger

gears

are keyed because frankly I have room for a key this one doesn't a key way and this would have cut the gear in two pieces so my plan is to braise this on now ideally this would be made as one solid part the gear is part of the shaft I wasn't able to do that because I don't have gear cutters and because of where this will be sitting
on the shaft sort of the depth from one end I wouldn't have been able to cut it on the CNC router the way I did just sort of a 2d profile it would have just been too long of a reach for those small end mills so let me break the torch out and we'll glue these two together would you believe I just spent 30 minutes turning my garage upside down looking for a brazing rod I know I have it because not two weeks ago I don't think I came across on a shelf thought to myself I'd better
wrap these up and put them in a dry place before all the flux starts to crack off they were the silver-based ones to know what those things cost that's like losing track of a hundred dollar bill all right well I think that does it for this video not too much happened but maybe you like something in there again this shaves some time off the official build video which hopefully should be out soon I hope you're all doing good and as always thanks for watching