MACOR is interesting material for sure and its been around for a long time. It was used in various locations on the space shuttle Thermal Protection System where high temperature and rigidity was required. Its low CTE made it the ideal material to use inside thermal barriers primarily so the barrier would retain proper shape. As shuttle TPS components go its density was rather high but it was very effective. We often reused MACOR parts salvaged from thermal barriers because it never goes bad. I work in the facility that made 1000s of orbiter tiles for the shuttle program. We continue to machine silica tiles using Hermle 3 axis mills for other NASA programs. Both mills are equipped with very high flow dust collection systems and lead screws are covered with in house sewn bellows. These machines have been in used daily for nearly 20 years and still hold tight tolerances. We typically get between 3 and 5 years out of the ballscrews. The message is get the dust out of the machine and position the vacuum nozzle as close to the part as possible to optimize machine life.
I have just started watching your channel and as an engineering student learning about CNC, the information here is priceless! You explain everything clearly and go through all the problem solving, showing your thought process. Love your channel, keep up the good work! Cheers
Worked in optics at one point. We would use cover glass and UV hardening glue to control chipping you can also use a a clear glass panel glued to the bottom of your work. That you remove with a heat plate
Good quality tape + NOT an aluminum base + tabs helps. I cut lots of sheet brass and copper on an acrylic table and long as you keep the heat down [air, mist or coolant] + leave tabs so your tool on the finish pass is not having to cut very much + a non metal base helps a lot. That said if I were to do those parts I would tape them BUT only face enough from the top so they are smooth + leave them with say tabs connecting them with stock on the bottom. Break them out of that "matrix" and stick in a vise. Is it less efficient... erm sorta but on the flipside you got WAY better process reliability to run a giant sheet out unattended! Plus you got both sides smooth and all that lovely stuff too...
Use hot glue . We machine macor often at the University I work at and we use hot glue to hold it down. Also I noticed you cutting to the outside of the part on the surface, you should have the cutter cutting to the center to prevent chipping.
Funny thing with the Ramp option; when you hover over it, it specifically mentions that Ramping is "good for ceramics, and other materials that need a constant tool engagement" (loosely quoted) :)
Great video! What feed rate, spindle speed, and depth per pass would you recommend on Macor for a 1/8" 2 flute end mill? I'm new to milling and I gotta make something out of Macor soon
It looks as if the material was chipping on the edges of the part when facing, I would recommend using radius on the cutter, so chips occur high up on the stock, another option is to do dynamic facing from the outside. I will like to buy one of these 440's you know what size rotary fits it?
I noticed the windmill is making a pass at the end to face the material, my thought/question: would it be easier to use a face mill to deck the material to finished height rather then making passes for each individual part? Something along the lines of a 2” face mill
If you were doing a production run of these parts, would a vacuum fixture, directly pulling on the macor make more sense? You could place a vacuum slot beneath each part to hold them down.
We occasionally do a few parts out of Macor, Shapal, and Alumina, while I haven't personally investigated, another local shop said machining it will void some warranties (so use your old beat up one!). We try to cover the ways and such with plastic or towels to try and keep the dust from getting too deep into things. And obviously avoid breathing the dust.
We use a dry bed machine with powerful dust extraction. Its true that dmgmori will void warranty on their machines that we have. But dmg do have machine protection that will let you do this, but we don't have it.
I'm not a machinist, would it be smart to use a facemill to get to the depth, prior to cutting each part? Would you save time on machining, instead of taking multiple passes on each piece with the 2mm endmill?
John, what would your thoughts be on using something like a Wegstr CNC for small prototyping projects or fine detailing work? Is there a gap that a machine of that type would fill in a shop, where a progression between sizes and quality of machines hits a local maxima of productivity?
Tabs man, I would cut it like a router user would do tabs plus attached to the vacuum plate useing the vac paper you get from datron www.datron.com/blog/5-tips-holding-small-parts-vacuum-table/
The reason you’ve got the job is 99.9 % of shops will refuse to machine it causes more damage and contamination of the machine then it’s worth.Been on the Apps for 25 year in the uk we will void any warranty cutting this material, that was the policy @ Mazak,maho,and maatsuura,@ WFL it’s standard if your cutting it you needs MQL and to run extraction with suction bells
MACOR is interesting material for sure and its been around for a long time. It was used in various locations on the space shuttle Thermal Protection System where high temperature and rigidity was required. Its low CTE made it the ideal material to use inside thermal barriers primarily so the barrier would retain proper shape. As shuttle TPS components go its density was rather high but it was very effective. We often reused MACOR parts salvaged from thermal barriers because it never goes bad. I work in the facility that made 1000s of orbiter tiles for the shuttle program. We continue to machine silica tiles using Hermle 3 axis mills for other NASA programs. Both mills are equipped with very high flow dust collection systems and lead screws are covered with in house sewn bellows. These machines have been in used daily for nearly 20 years and still hold tight tolerances. We typically get between 3 and 5 years out of the ballscrews. The message is get the dust out of the machine and position the vacuum nozzle as close to the part as possible to optimize machine life.
I have just started watching your channel and as an engineering student learning about CNC, the information here is priceless! You explain everything clearly and go through all the problem solving, showing your thought process. Love your channel, keep up the good work! Cheers
I love your videos using the 770 and the 440. Cool to see how these machines can hold their own.
Clever trick about leaving a little bit at the bottom then keeping 3 thou in radial clearance for the final depth!
Worked in optics at one point. We would use cover glass and UV hardening glue to control chipping you can also use a a clear glass panel glued to the bottom of your work. That you remove with a heat plate
All fusion and tormach 440 videos are very helpful thanks very appreciated plus
Good quality tape + NOT an aluminum base + tabs helps. I cut lots of sheet brass and copper on an acrylic table and long as you keep the heat down [air, mist or coolant] + leave tabs so your tool on the finish pass is not having to cut very much + a non metal base helps a lot. That said if I were to do those parts I would tape them BUT only face enough from the top so they are smooth + leave them with say tabs connecting them with stock on the bottom. Break them out of that "matrix" and stick in a vise. Is it less efficient... erm sorta but on the flipside you got WAY better process reliability to run a giant sheet out unattended! Plus you got both sides smooth and all that lovely stuff too...
Use hot glue . We machine macor often at the University I work at and we use hot glue to hold it down. Also I noticed you cutting to the outside of the part on the surface, you should have the cutter cutting to the center to prevent chipping.
Funny thing with the Ramp option; when you hover over it, it specifically mentions that Ramping is "good for ceramics, and other materials that need a constant tool engagement" (loosely quoted)
:)
Miteebite mitee grip or crystalbond would help you out with work holding the plates down.
Great video! What feed rate, spindle speed, and depth per pass would you recommend on Macor for a 1/8" 2 flute end mill? I'm new to milling and I gotta make something out of Macor soon
NCVIEW, gotta check that out. May have a hold down fixture for your next time. Will drop you an email. Great vid as always...
It looks as if the material was chipping on the edges of the part when facing, I would recommend using radius on the cutter, so chips occur high up on the stock, another option is to do dynamic facing from the outside. I will like to buy one of these 440's you know what size rotary fits it?
The Carbide 3D Nomad machines Macor really well and it's so much cheaper than a Tormach.
I noticed the windmill is making a pass at the end to face the material, my thought/question: would it be easier to use a face mill to deck the material to finished height rather then making passes for each individual part? Something along the lines of a 2” face mill
how do you change the fusion colorscheme?
great video as always!
Cool and extra points for the cold war quote : ). What are these, mini brakes?
If you were doing a production run of these parts, would a vacuum fixture, directly pulling on the macor make more sense? You could place a vacuum slot beneath each part to hold them down.
Despicably Irascible Rapscallion Yes! Here's a whole video on how to do exactly what you said: th-cam.com/video/ZpDq_q3JX1c/w-d-xo.html
looks to me like a special clutch or brake pads.... or what is it?
What was the cycle time for this? I would imagine a couple hours, no?
Who makes that boxcutter at the end?
I think it's this one
www.amazon.com/Gerber-EAB-Pocket-Knife-22-41830/dp/B0016KHW2W
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Ceramic on a milling machine, doesn't the dust ruin your ways on the long run? At least I wouldn't put it onto my Maho/Deckel.
We occasionally do a few parts out of Macor, Shapal, and Alumina, while I haven't personally investigated, another local shop said machining it will void some warranties (so use your old beat up one!). We try to cover the ways and such with plastic or towels to try and keep the dust from getting too deep into things. And obviously avoid breathing the dust.
We use a dry bed machine with powerful dust extraction. Its true that dmgmori will void warranty on their machines that we have. But dmg do have machine protection that will let you do this, but we don't have it.
I'm not a machinist, would it be smart to use a facemill to get to the depth, prior to cutting each part? Would you save time on machining, instead of taking multiple passes on each piece with the 2mm endmill?
look closely the part is not flat as modelled it slopes in the CAD
Ah, didn't see that!
Some kind of insulator for an electronic device maybe?
I wondered but if they were I'd expect them to be arc segments rather than rectangular.
muito bom amigo ,top
Vacucard maybe
I think the you tube decided to post this before he wanted it to
we're launching the Wednesday Widget at 7PM EST Tues PM now ;)
GETTING A HEAD START ON THINGS NICE KEEP UP THE GREAT EDUCATIONAL VIDEOS
John, what would your thoughts be on using something like a Wegstr CNC for small prototyping projects or fine detailing work? Is there a gap that a machine of that type would fill in a shop, where a progression between sizes and quality of machines hits a local maxima of productivity?
Carbide 3D Nomad is great for this. PCBs too of course.
Can the 440 do carbide?
wow how weird is this! today was my first day ever machining this material ! very different then your standard metal.
Here I am paranoid about the glass in reinforced nylon wearing out the machine early.
Tabs man, I would cut it like a router user would do tabs plus attached to the vacuum plate useing the vac paper you get from datron www.datron.com/blog/5-tips-holding-small-parts-vacuum-table/
The reason you’ve got the job is 99.9 % of shops will refuse to machine it causes more damage and contamination of the machine then it’s worth.Been on the Apps for 25 year in the uk we will void any warranty cutting this material, that was the policy @ Mazak,maho,and maatsuura,@ WFL it’s standard if your cutting it you needs MQL and to run extraction with suction bells
2nd