How to make a custom milling machine cutter.wmv
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- Опубліковано 9 вер 2024
- This video shows how I made the special cutter for my cannon ball project. I covered this info. in my "cannon ball mold" video, but with this being specialized information, I made a separate video. Don't polish objects in a lathe the way I am in the video! You can loose a finger and thanks to guys for pointing that out. I'm just a hobby machinist with no formal training so I appreciate comments from experts!
Kind of nice to find someone not afraid to be different by letting his imagination lead the way. Thank You! JD
It's easy for people to be critics, don't worry about the speed and feed, this isn't Heidenhain and Hitachi Tooling, this is basic equipment.
Great innovation - Impressed
Well, being a self-taught hobbyist, I thoroughly enjoyed the video and especially the comments. Learning more from the comments than I can learn on my own.
I appreciate the input you guys have on this. I have learned more from the comments for some of these projects than from the projects themselves!
I don't have the skills to do such creative work, but am amazed at the respect, and unselfish advice, shown towards each other on this site. This impresses me as much as the skill level.
Good video and great use of what you had to work with. Ability to accomplish more with less is what separates the men from the boys. I am a machinist in the injection molding/stamping die world, and the main recommendation I would make on this project is this: Since you already have the block of aluminum in the machine, when you finish your ball pocket, drill and ream 4 holes around it (probably 1/4" would be sufficient) in known locations say .750" from center in each direction for dowel pins.
If you need to make this type of cutter again , try making it 2 fluted like a spade drill. 2 flutes will support each other and you won't get the wobble like the one flute. This is easier than trying to get the precise back clearance angle needed for a single flute cutter to support itself. And slow down the spindle to 300 or 400 rpm. This will let you push the feed a little and the workpiece will do more to help support the cutter. I find the best cutting fluid for aluminum is kerosene. And to get a cleaner parting line on your molds take that raised edge off with sandpaper on a flat surface.
Well it didn't seem to harden when I first quenched it in oil, I didn't show that in the vid, because it was a catastophe haha. It did seem to toughen up a little when I quenched it in water, but I could easily cut it with a file afterward. Thats why I used Kasenit.
Kasenit is great stuff... For machining aluminium and brass, cutters made from mild steel and case hardened are very serviceable, as you found. You just need to take your time and keep them cool with plenty of lube for Aluminium (kerosene or diesel works best) and run them dry for brass. For 'one off' jobs it's a lot more economical than tool steel. I have also made 'flat drills' out of old worn out files for drilling large holes in everything up to medium hard steels. The file steel can be ground to a good cutting edge, mounted in the toolpost, carefully centred so as not to cut oversize, and fed into the work via the saddle traverse. Works a treat for roughing out before reaming to final size. For really large drills you can put wooden or plastic steady pads to prevent chatter..... Extra good for deep holes where a single point boring tool runs into flexing problems causing digging in and bad chatter, because the opposed cutting edges of the flat drill balance each other out. You do need a pilot hole though, but it's easy enough to turn down the shank of a twist drill a bit, and braze it into a bit of rod drilled out to fit to make an extension as long as you need, silver solder is strong enough for this, and you can retrieve your drill bit afterwards quite easily.... Stick the business end of the drill into a large potato while brazing to keep the heat away from the cutting surfaces....although that's a trick you probably knew about anyway!... :-)
Reminds me of the first tool I made in machinist class. It was a fly cutter . I was so proud of it I blue it. Teacher gave me an A for it . Made it to the tolerance of the blue print . Even did a good job of grinding the hi- speed tool bit. 1st thing I used it for was to cut the radius on aluminum piller bedding blocks for a Remington 700.
I really enjoyed watching this! I love metal working, because you can give life and function to just random pieces of metal.
Even with the little mistake of not cutting the tip off center, the end results where quite good for a great learning project.
Keep up the good work.
Even so may I add an EXCELLENT piece of engineering......Anyone who is a "proper" Engineer WILL KNOW....NOTHING IS IMPOSSIBLE...just that miracles take a little longer!!!!
Excellent video and well done on the home made tooling. I am but a novice machinist at best and when you mentioned about the lip that was left what popped into my mind for a possible solution was to taper the tool head back. You did what you needed to to get the diameter of the cut so anything that remains seems to be waste for the most part. It just seems to make sense to allow for a bit deep cut with no lip remaining. Great job...
Good work, you are learning much more by making a cutter than buying one.
A classic case of 'doing what ya gotta do to get the job done'. Warts n all, great job!
Just seeing this for the first time and kudos. I appreciate the fact that you are responsible enough to give the warning about how not sand. I was cringing as I watched but glad to see you put up some warnings. That will grab and steal a finger before you even new it happened. anyways hope to see more I have a couple questions soon
Enjoyed the video. 1) Sanding on the lathe comments...also be careful when using the sanding strips, use both hands, thumb and finger. One hand with strip around the work will catch and wrap up the strip with your thumb as an anvil. I learned that one the hard way. Two hands, open V, pads of thumb and index lightly.
Good Video, I like how you used the case hardener to solve the material problem. Now for those out there whome seem to have a problem with Metric V,s Imperial(Inch) Aus is now metric but was not always. It is this simple there is 25.400mm per inch! If you do not have enough Maths to do the conversion use your computer (online conversion) Also note the tailstock o the lathe used is graduated in both systems! The other easy one I remember is 39.37"/Meter and so 39.37 Thousanths of an inch per mm.
It's cool you're making your own tooling. A couple quick tips, When you were measuring on the lathe for the offset distance, to find the Dia of the radius on the tool nose that you made. You can use a dial indicator on a mag base. It's a lot more accurate, also drop your R.P.M. down when milling and up the feed a little. You will get much less chatter a nicer finish and the reduction in speed wont overheat the tools causing them to fail.
Don't be shy about scarfing out to the edge on your cutter for sharpness.,as long as there's enough relief behind it wont alter the radius.And TapMagic is as good as it gets for cutting fluid.(In my humble opinion)Great video.
great! i love people who make their own tools
You can buy drill blanks for doing this. I've done it. And usually with what seams like no tolerance. Also... from my stand point , your speed was off. Slow it down, give more feed and there wouldn't be chatter like there was
Since I suspect you're having trouble with your tip cutting, you might think about taking your ball nose cutter nearly to depth to get better results. The last little bit of depth should still give you the same finish effect were the tip of the butter is bottomed out, reducing your vibration/chatter. I think it's awesome you were able to make a serviceable aluminum cutter from mild steel.
a fine flat file will do the job of taking tha ridge off just fine then some crocus cloth to fine pollish the whole thing but you did a mighty fine job and my dad agrees he's a retired machinist and im learning ,nice job by the way its amazing what a little surface hardening will do
Suggestion. To make neater back clearance on your ball cutter, you could have put your four-jaw chuck in the lathe, then off set the center of the cutter a couple of thousandths directly back from your planned cutting edge. Then, using your spherical cutting tool holder, you could take off a precision bit of metal to provide the back clearance on the cutting edge.
One trick is to put the bar in the chuck way off center, maybe .020" to 1/4" and machine the shape in the flailing bar until it just cleans up all the way around. When you spin it normally the shape sweeps around and the max radius is where the cutting edge will be. The rest of the shape slopes away to provide cutter relief automatically. The offset would introduce some errors in the ball shape though, but for profile cutters that don't go to the center the method works great.
Nice job, i think a bit slower speed was called for on that size of cutter . With aluminum i know fast is always used , but old guys do have years of chatter . I too like making my own molds and tools of all kinds. We made our own tools back in vokie in the 70s . Hardened and ground , surface gages , planer gage's, squares , calipers lots i used my entire life.
They told us similarly in the early 70s. I was learning the metric system in the 5th and 6th grades. I changed schools about half way through my 8th grade year. At my new school they were just teaching metrics. It was funny that the teacher knew nothing about the metric system. I actually ended up helping her teach it, lol. 40 years later and we still haven't switched, although I believe they are trying to slowly.
thanks for the shout-out it seems to be working much better. it also looks like you need to invest in a rotary table. that would have made dishing out your cutter much easier.
My master always taught me to cut towards the solid jaw of the vice when making a cut on the side of a piece so as to introduce as little variance as possible, just a little tid bit there. And, if my math is correct, you should've been running at 400-350 rpm; but that assumes a perfect cutter and coolant and all that happy crap so really more like 300-250 rpm. The formula if you don't know is 4×110÷dia. 110 is the cutting speed for steel, its something like 290 I think for Al. Awesome job though! It looks great
just a tip for if you want to improve your cutter's finish:
try making two cutting edges(one at 0 degrees and one at 180 degrees),
This way your tool won't be so imbalanced and you won't get those bumps (caused by the vibrations) on the surface.
For a home made cutter you did a pretty good job. The RPM seemed a bit high though considering it wasn't a carbide, or even a HSS cutter. Lower RPM might help with the chatter even more. All in all, nice work :)
I'm impressed !!!
Very surprised to see mild steel work so well.
I have subbed to see what else you come up with.
Matt
that is a great job you did on that cutter, good video very informative. Making the tool out of mild steel is fine , but if you want to make better mild steel tools get yourself some case hardening powder. Easy stuff to use, just heat up the part to bright orange then bury in the powder and leave it to cool. Only problem is you cant sharpen it too much or youll go back through the case hardened layer.
I enjoied the video. The cutter seemed to work well for what you were using it to acomplish. During the process with the custom cutter one can clearly see the wobble of the cutter as you were bottoming it. This likely due to the offset weight of the cutter head and the fairly high speed you were using. A design with two opposite cutting surfaces would have made a balanced end. Also increasing the body diameter of the cutter shaft in the middle would tend to dampen the offset weight of the end, as would slower speed. Highly innovative! keep up the good work.
Nice job for a Home machinist , i would suggest for safety ( if not already mentioned ) use your lathe chuck to hold the work piece when using the dremel to grind it down - less chance of loosing skin on ya hands and you can work a lot more accurately - just put lathe into very low gearing to stop chuck turning
Alternatively you could use a boring bar head set to the diameter you desire then turn it on a 45deg angle to the work with the work on a rotary table, and by rotating the rotary table you will generate a perfectly concave hole of the proper diameter. This will also make for chatter free single point cutting. Great job on the one off cutter though!
A suggestion to make setting your radius tool more accurately than the "eyeball" caliper method you used. Assuming you don't have access to gage blocks, make one the appropriate size. Turn a piece of scrap down to the .546 you were looking for and manually touch off on the cutting tooltip and the center of your arc (in the video it was a square). You could also grab a few items of known dimension and make up the difference with some feeler gages.
hey, im not sure how useful this may be for you but if your endmills are high speed steel i highly recommend using some form of coolant, if you dont they burn out, their rockwell changes and can snap for no good reason and cost you more just having to replace them
And that's the beauty of being a machinist. Don't have the tool/bit you need? No problem, just make one.
Great project . Just a tip of sharpening (anything) you can see if something is sharp just by looking directly down at the cutting edge and looking for bright spots (try it 1st with knife blades) if you can see any reflected light its blunt! You can clearly see in your video a big bright spot (21.30) on the edge exactly were you worked out it was dull by the bur it left. i would use a diamond burr (they dont chatter like stones) in the dremmel to clean the live left by the ball mill
Nicely made cutter. If you want to be good to it, you can without a doubt turn down the rpm's when using it. Custom cutters of that size are usually more effective with low rpm's. Also when working with aluminum, using methylated spirit or ethanol is much better than cutting oil. Gives it a nice shine aswell.
Ok, thanks. I rarely change the mill speed but will now with larger cutters.
Your cutter made great looking chips, nice job!
That was a superb effort to say the least. Don't be to hard on yourself either. Very cool. Greetings from Arizona.
+Thema inproblem Thanks! Hello from GA.
The measurement method matters not. The job was done with precision using the imperial system. The results speak for themselves and the machinists skill. Thanks for a great show of your skill. Experience wins over the metric system when you have grown up with it and all your machines and instruments are imperial. There is always more than one way to obtain the desired end result.
Great stuff! If you want to get the face of the molds nice and flat, try putting a piece of oiled ~800 wet & dry sandpaper on an old photo copier glass and polish it in a circle 8 pattern. The copier glass is very thick, quite tough (for glass!), and VERY flat (like, optical flat! Go figure!). You can also get it for free if you find a place that's tossing an old dead machine. I get all I can find, then stash it for when an "oops" happens and I kill one. :)
it seems to have worked well. one thing you can cosider is that the closer you are to the center the cutting force/speed goes to 0. so like you would when drilling for a larger diameters. try predrilling so the outer side is doing most of the work and leave some material for the last depth cut. less preasure and loading ont he cuting edges and less chatter. good luck. =)
The end result is the only thing that matters, but I do have some input. When you dished the face out initially, any material removal beyond the profile edge changes the profile and will be obvious on the final part. For steel, that same dish didn't need to be so deep. Same thing goes for the backside relief. Anyone trying this needs to be patient and careful. I also agree with some of the other comments, you may have been better served with a multi flute cutter, and your spindle RPM was way too fast.
Very informative... I don't have a project at the moment... but definitely will find it useful at some point. Thanks.
not bad for making your first 'ball' cutter ! :) next stop, multi flute to stop the spindle wobble (slight). noticed it on video.
Amen on the cutter speed, the rest of what you said is also correct but his cutter speed was the main problem, that and the tool was dull even though he didnt think it was, it was really pushing bad. It would never have cut the block if it wasnt aluminum
Next time you made a sphere boring tool, use your lathe radius cutter to turn more than 90 degrees, so that you don't have the ridge. If you want to get correct sized balls, your cutter needs to have more than 1 cutting edge, so that it's balanced and doesn't flex when the tip gets to the bottom of the hole. The reason you have a nice surface finish is because the cutting tool is flexing into the hole, like a C shaped spring (groove?) fits into its groove.
nice video, very informative and professional! now i don't know what kind of lathe and milling machine you are using, but i would say that you need to bring the rpm's down a good bit if possible, allot of the shrieking and vibration would go away.
Hey mate you have taught me so much I can't wait to get home and have a plan with the mill
Greetings from Toowoomba Australia
Toowoomba...now I'm gonna have to google that!
I was using cutting fluid, do you think I should have been using cooling fluid also?
Continue to learn buddy, you are on the right way. Use Coolant on your tool if you can: longer life tool and this avoid to burn the piece with the tool.
The radius can also be done with just a simple roughing an d a god job with the file and a radius gage home made or not(bought) it's thaàe less expensive way to make a radius.
Very cool project. Love the learning curve thing, just keeps getting better.
That was interesting to watch Thanks for showing the corrections you made to the tool I think with the right material (steel ) you could perfect this cutter It made a nice mold I Will watch more of your videos on the cannon
Just as a tip. You should create a 2 face cutter instead as it will do double the work in each revolution, also when you heat treat it, make sure you heat it up almost red hot and then drop it into cutting or hydrolic fluid to harden it, if you harden it well enough and it is sharp enough, you'll end up with a very strong tool. Well done on the video though.
It worked so I say well done and I hope you make a vid of the rest of this project I would like to see your method of matching and sprue cutting. When I use emory cloth to polish a shank I back the cloth with a flat bar to keep from making waves in the shank the bar makes it work like a file and is easier to control
Looks good. I haven't seen a radius head for a lathe in many years. I would have run the mill a little slower though, it would have minimized the amount of chatter.
If you mix mineral oil and water, it gels up. I tried it and it works 10 times better than cutting fluid. Just brush it on, and the oil lubricates while the evaporating water cools. I can take fast heavy cuts and touch the part right afterwards and didn't even heat up. Mind you it was steel, not aluminum
I grew up as a carpenter and things can be built fast. But i wish i had the money to buy all theses tools and make metal parts.
Really enjoyed the video, great to see you making the tools as it gives us an idea what we can achieve. I'm pleased you had some problems as hearing you nut out the solution was great. Over her we would say you are "a clever bugger" Gordon, Australia
Thank you sir!
oh and i love the circle cutter you have for your lathe too
Use sandpaper in strips hold so if the strip was to break you would take a step back (behind the part) you can run the strip up the part now freely I do this alot when im finishing tolerances on manual work
Good video. always good to see different methods for home made tools.. Take a closer look at the profile on the tip of your "Ball mills" to get a better idea of how to shape it. If you have a rotary table, use that to create the relief on the cutter edge, otherwise do it with a 'dremal' or similar rotary tool by hand. As its made from 'mild steel' run it at slower RPM and it will cut alot smoother. Keep it up ;)
Your custom single fluted ball and end mill looks like the cutting edge was hand forged before heat treat. Am I right?
Very creative. It really got a nice finish.
When it chatters. Slow it down, especially with an em as rigid as that. You just have to deal with chatter on longer ems that have more flute cut away.
Your right, not getting close enough to the edge at the widest portion of the cutter didn't allow it to cut well. Thanks1
Your not the only person to mention that, thanks. I guess the best way is to just hold the sandpaper and not touch the part correct?
Nice work. however if you ever have to make one of these cutters again instead of cutting half the material off and then splitting that material in half again(leaving you with a 1/4 of the material) giving you one cutting edge I would try(since you have use of a mill) taking off only a 1/4 then spin the stock around and repeat the process and then dish it out and so forth. It would require a bit more work but it would give you two cutting edges putting less train and wear on each edge
Look up " Russian lathe accident " and suggest it to anyone that's thinking of playing with a lathe. Im Old school , I don't calculate speeds and feeds ive learned to eyeball it and change the feed or speed to do what I need it to do. I noticed you milling at "Gorilla thug machinist " ( on Facebook ) speeds . Whenever possible do not climb mill on a manual machine and try to find a happy medium between gunsmith speed and gorilla thug machinist speed . Mr. Aumick is spot on with his suggestion of the spade style cutter , A-2 will work quite well for aluminum.....As for hardening you can try a mix of old motor oil ( not this new synthetic stuff ) and horse apples, suspend it , don't drop it in or it may warp and only harden on one side. Or a pack hardening method . its easier if you know what your starting with.
I suspect that was a bar of medium carbon steel as it hardened so easily. I used to torch heat treat tool steel. Heat soak for a longer time to increase the hardness depth. BTY, I get custom radius end ills ground a few times a year. A local shop do them for about 30 USD.
if you would drill 2 holes beside the bar with the cutter on it, you could insert to pins in there, and place a piece of flat bar against the pins, that way, you can setup the radius far more quick and accurate..
if you'd take 2 pins of ¼ inch, and drill the holes 3/8" "behind center, when you'd put a ¼" flat bar against the pins, the part facing the cutter would be over the center of the radius tool.. now you could measure between the flatbar and the cutter..
With no computer control, how did you follow the outside outline of the workpiece so precisely with the ball end mill to develop your rough cutting edge ?
Thanks for taking time out to share this video, I really enjoyed it
Also, i suggest you making two pin holes before hand so it will save you some time aligning those halves
Quick reference calculation. R.P.M.= 4X the cutting speed of the material/Dia. Mild steels: 100 sfm, brass/aluminum: 400 sfm. You can find the cutting speeds in the Machinists Handbook or online. I typically, when conventional milling take the R.P.M. that is calculated and use either 1/3 or 1/2 of it. Have fun :)
Do a search for super-quench and you'll find a solution of salt/Dawn dish detergent/Jed Dry to harden mild steel. And I wouldn't swear to it, but I believe you only need to heat the steel to the point it's not magnetic, not necessarily to an orange or yellow. Fun process, thanks.
that is a beautyful simple system.good job
I've added notes to the video explaining I'm doing it wrong. Thanks, I'm just a hobby guy learning as I go.
that worked out really good. loved the video
Please man I need your help:
I need to know what is the cutting force for low carbon steel and forward force too.
I'm trying to implement a CNC milling machine and need to know what step motor to use.
Could you help me with this stuff ?
Thank you !
I really don't know. I don't know how to measure it either.
wont it want to vibrate and possibly damage the machine if its not symetrical? ( the center of mass is out of place )
Good video! Thanks for your sharing your experiments, & resaults. If I may, I think your problem with the egg shaped contour was one I had with my first try at a sphere. The X axis was too far to the right at the start of the turning. I learned that if I set it up that I would end up cutting about .020" off the end with the ball cutter, I would attain a truer sphere, than I would if I tried to finish on the exact LH end of the blank.
Hope this helps, from another dumb amateur iron mangler.
Nice technique to make that curve!
For the price of just one foot of 4130 the dia. I needed to make the cutter, it would have put the cost of the project out of budget. I had to use what I had and hope it worked. Luckily, it worked well enough for a one time job.
Nice work! For more searching, these are better known as 'D' bits.
I hope the makes sense..I am a machinist as well and I wish I could draw a picture to better explain it. I guess it would have been easier to say take out a 1/4 of the dia spin 180 and another 1/4 dia cut.leaving two pieces that could be made into cutting edges extending the cutting life and decreasing the relative cutting forces on each edge.
that is super cool man
got me thinking about new ideas...
I guess I'd have to figure in the time I put in making the ball turning toolpost, so I'm not sure. It would well worth the money spent having a custom cutter made if you were going to make 100 of these things.
what type of steel did you use to cut the material?
Nicely done. I learned a lot watching your video. Thank you-
personly id harden everything last
but love the ball cutting tool i need 1
You go to MIT and they practically use only metric. When speaking layman terms and trying to give the scale of what they are talking about, they use imperial since people are used to understand how much is in a gallon or how long is a football field, but that's the only time when they do it.
They use metric there since it's the system of science, when converting from volume to the size of container or when converting arbitrary length into arbitrarily smaller units (kilometers to millimeters).
Not sure if this would be any better idea, just an alterative. How abut putting the job in a four jaw independent chuck and use your radius cutter facing outwards.
I need to do or bore a 5 in. X 2 1/2 deep in t 1 material , need help.?