We have a look at an Uber-expensive SKF Magnetic Linear Actuator. It's not as skookum as you'd think.🔥Safety Squint T-Shirt! teespring.com/SafetySquints_us Shop Gear www.etsy.com/ca/shop/AvEwerkz
I really appreciate a youtuber who fully illustrates how they've failed or made a stupid mistake. It's a refreshing change to see an honest person without the neurotic self absorption that makes people create overly scripted, overly polished perfect "look at me", essentially selfie youtube videos that fall along the spectrum somewhere closer to an oiled up Kim Kardashian with silicone fish lips. All filmed from a selfie stick talking about the newest, most fashionable social cause, i.e. adopt a Somali pirate baby and name him after a popular tropical fruit, or how impatient Donald was by over feeding ornamental Japanese goldfish. Anyway, thanks AvE. That's what I meant to say.
Yup. Probably couldn't as he is likely a citizen of Canada not USA. Reminds me I voted last night... we have these clusterfucks of ballots with "Ranked Voting" which seems a royal PITA. We actually have some NEGATIVE vote value results. Oh, the humanity!
aserta thats what you say now, but once she finds out that is going to be really expensive loctite. It can go 2 ways. 1 will probably involve a hospital or other medical place of some sort. And the other 1 is going to involve some lawyer and you are going to lose atleast half of your stuff.
I have a caveat about the skookumness of the gearing: Yeah, they'll die slowly if they get warm, but it says right on the thing that it's rated for a 1:9 minute duty cycle. Ain't gonna get warm if you use it like that.
Yeah, but if you give the switch to the apprentice - good luck getting him to only play with it for a minute. Unless there is a temperature shut-off in the electric bits - it will get used more. Cheap stuff says "You used it wrong", good stuff doesn't break.
first of all cheap stuff dosn't say you used it wRong, it says you used it wong. Now that that is out of the way we all know that the apprentice wont last more then 30second playing with a shaft going up and down...
@AvE I cant but Im pretty sure you can calculate the force on those plastic gears so the whole actuator can withstand 6000N which is around 600kg. All in all, I’m pretty sure those gears don’t need to whitstand a lot of force. And the argument that plastic shroud around those two gears can colaps, it cant because as I saw it sits in a round aluminum tube of the same diameter so no play for that thing. Days of all metal and skookum are over but still there are good stuff, they r just made with economy in mind. If plastic is ok to whitstand 150% maybe even 200% load why bothering machining or sintering metal gears and housing. Swiss r smart, I wouldn’t question it. Btw once again a good video showing some skookum stuf
Bogdan Markovic i purchase a lot of stuff swiss made (read $$$$) and they use Acrylic Delrin FR4 Nylon for construction. Some of it is required to be RF transparent. It costs a crap ton. Most things work just fine but every now and then one of those parts fail bc of the engineering not the material, which is usually engineering with that (wrong) material in the first place.
Yep, all of the above. The beauty of good engineering is understanding the requirements of the job and building something that does that job, with the minimum of parts and cost and that will last the projected lifetime. Sure, you can build it with metal gears, but all that might do is just drive up the cost and weight. Any fule knos that it's easy to build something complicated- the art is building it as simple, as economical and as efficient as possible. In this application, metal gears may be more inefficient in terms of costs.
cheradanine that is why over engineerd means weaks as F. Something that has been over engineerd has been design to just barely stand up to the job it has to do for the amount of time it is intended to do that job. Poorly engineerd means skookum as frig. That stuff is way over build, strong as hell, no failure mode because if you dont know how strong it is and it should be better just make it a bit stronger to be on the safe side. That is probably why us amateur builders tend to build things a bit to strong. No calculations? Wel just put in a bit more then you think you need and its probably 2-3 times stronger then it needs to be.
Hey AvE, there is an anti-backdrive mechanism in that support bearing housing. Ball screws have little friction, so the actuator would extend or retract with a little load if the motor isn't holding position. Thomson linear has some pictures of their backdrive mechanism, basically a brake that locks up tight.
My swiss ol lady I bought off the eBay felt the pain when ya called her a sweed! She gets that shit all the time, then I gotta show them the bill of sale that came with wife hahaha
"Two Poles go into a Hall" sounds like the start of an ethnic joke, not a sensor description! I wonder if there's a Czech in there somewhere to keep an eye on them?
In addition to testing those rusted nuts, it would be nice to test which solution is best for keeping the bolts in place. Stuffs like loctite, nordlock wedge locking washers, spring washers and lockwire.
I've worked on some equipment designed by some Canuckistanians who didn't understand what salt and water does to steel. Black steel plates connected with f**king countersunk 1/4" allen key bolts with nordlock washers under the nut. Try disassembling that shit while hanging in a wire 60 meters above the north sea after it has been there for 2 years and it suddenly fails to everyones surprise. Oh, and during assembly they really splurged out on lunch and forgot to use grease at all. Those nordlock washer are crazy, if I need something to stay put, that's where I'll put my money. Safetywire comes second.
Have had a Centurion actuator drop a motor, and that motor was so well sealed that only after I had it out and opened it could you smell the crisp. Sealed up pretty well, the only thing was that it would run poorly, and looking after at the cremains I was not surprised. New motor and it was fine again. Now I just keep a service exchange unit, and it is a simple matter to spend 10 minutes doing the swap and then fix the other as spare. Not as nice as that, but for something that lives outdoors and runs 100 times a day getting 2 years out of them is not bad.
great point on hyd ram force being different in different directions because of the rod in the cylinder. Never even occurred to me. man i love this channel!
My wife (a Pastor, by the way) walked in the room right at the "sweet 16 and never been chooched" comment, and now I have to explain shop porn to her. Thanks for the chuckle AvE!
The outer cage is easy to stretch cause it's out of extruded aluminium housing. It has pretty tight fit there and it would definitely prevent from stretching.
This is why we build our own actuators for our foundry. Servo drive, 3000 lbf, beefy ball screws, proper seals and gaskets, hard chromed shafting, service every 3 years out of pure curiosity.
Dear Uncle B, The best way to get those nuts good and rusty is using a cyclic corrosion test setup. 12-14 days in cyclic corrosion can be equivalent to approx 1 year in a rusty environment. You need to mist (or spray) the parts with a salt water solution, then dry them with a fan or elevated temperature, and repeat. Best of luck! Ps. Would love to see you build a quick and dirty diy cyclic corrosion test chamber!
Nice to see this good stuff... I, Instead have had a lot of bad experiences with electronic stuff made in Swiss, expecially air-extractors, everything was sturdy and worked perfectly but when they broke down they always were unfixable
14:53 I cranked my head around to try to see. Wish my teachers were as "colorful" as you. Well, my military teachers were, but that was about murder lol, you can't be all too serious.
Quadrature encoding with the 90 degree separated sensors! An attached brain would be able to extract RPM and direction. The two pole magnet and the 90 angle between the sensors would allow you to extract 8 clicks per motor shaft rotation and watching the phase relation between the transitions on both sensors will allow detecting direction. Knowing the total gear train reduction would let one calculate the position of the actuator, presuming there is also a signal available for either limit. Run it to one limit, zero a counter. Each encoder tick is 45 degrees of motor rotation, from which the linear position can be calculated, within the tolerance of ball screw backlash. Love this stuff....
If you want to see some accelerated rusting I would try putting those nuts in bleach overnight. I found this out by accident when doing some experimenting with de-chroming some tools. I don't know the science behind it, but it sure did make those tools rust.
It's the chlorine. Halogens attack iron with a vengeance, producing deep pitting almost immediately. Even just off-gassing from pool bleach tablets in a tool shed can destroy steel tools.
A touch of Ferric Chloride will really speed up the rust. Since it's acidic it will remove any surface contamination and it justs likes to rust with the oxidizer side.
ok, its good to know im not the only one with a get to er later pile...lol..suggestions? your the tear down guru! no doubt my get to er pile is way bigger than yours...but i do learn alot from you. great vids.
20years ago I did my apprenticeship at Magnetic. This was before it was part of SKF but even back then the main focus was getting the price down. More and more parts were outsourced and production changed to assembly. Unfortunately I have no idea how to put this all back together but I'll ask a friend who worked there until recently
Took apart a massage chair motor after years of abusive massaging, and she was like new! The nylon gears were hardly worn. That's what makes them quiet, and no need for lubes. It was Swiss made as well. Try that with metal gears!
It's a sad world where if you want to get something really good it almost has to be exclusively swiss made. After breaking 3 garlic presses I bought a Zylis for 22 bucks. A decade later its till Chooching. $100 for a swiss made (pfletscher..sp?)double kickstand. Both appear to be made out of the same aluminum/magnesium looking alloy.
I want to say that the nylon gears are likely the most appropriate choice to implement a design-for-failure feature. Considering that its rated load isn't relatively high, if it were to fail, the gears themselves would be the easiest and likely the cheapest to replace rather than the proprietary motor or actuator (not to say the gears aren't proprietary either). Furthermore, it wouldn't be wise to have glass filled nylon on the account that it is soaked in grease and would be susceptible to moisture ingress plus, would also reduce its wear resistance. That being said, I would argue that the nylon gears would be a fine option for this actuators intended purpose. Any thoughts?
Dude does the final position of shaft matter on Assembly I.e in your pivot end is on the diagonal to the case ? Just a an observation in my head it didn’t look right to ones I fitted on a posh house gates love the vids bro info packed and a inspiration for all peace
Hi. Thanks for the brass-shim trick! Magnetic viewing film - awesome, I'm buying that today. Plastic gears? Argh.... Well, something has to break if it jams up entirely. Sure wish it would be a plastic replaceable crush rod, instead of specific gears that are nowhere to be found.
I'd really love to see you compare the Chineseum craftsman 1/2 socket wrenches to the USA made wrenches... and those compared to kobalt and harbor fright as well... I have quite the hard on for usa made craftsman tools, to a fault.... I mean who really needs 2 dozen 1/2 inch ratchet wrenches lol, guess I do... I'd love to see full tear downs of the chinesium craftsman vs the usa craftsman as well.... I love your teardowns, keep em cummin! :-)
AVE love the intellectual content. I’m currently in a welding program in the great United States. I was wondering what type of post secondary education you have? This stuff you do really interests me. Keep it up.
Damn Right! Time to take some shit apart! Got my tool box loaded with the essentials ...Screwdriver , hammer and a pair of vise grips. That fails time to fetch the Heat Wrench!
You could try milling out the housing along the length where you're having the innards gum up on you so you can get in there with some "persuaders" to keep it in line and unbound.
ok my two cents worth the two screws on the side are to hold things in place try sliding one have down line up screw and lock her in place then slide other side in.now the first side won't be pushed to far to where the second side installed won't push the first side out of place. If it works I would love a blonde one rule and a t-shirt.
DOOOOOOD, have you seen that fancy new insert brand sawzaw with the buzzkill tech and probably other fancy words too? Looks skookum as frig man, but I bet she looks better on the inside. Plus, what man doesn't want to get more reciprocations without getting the sweats?
You need to watch the ad that was playing beforw this video: the ad was for the automated toiled bowl cleaning brush that spins around the bowl cleaning. Anyway, this might be a fun project to fabricobble on your own at the shop. Plenty room for integration of arduino, motors, solenoids, switches, relays and who knows what other dangerous devices.
I think the nylon gear housing isn't structural, it's just there to hold the gears in place while you insert it into the giant aluminum housing. Once inside, it's not deforming without bursting the AL case. (In fact, being thin is a virtue; less compression.)
Jeremiah Blatz That isn't just a nylon housing. It's one of the key mechanical parts of the force transmission in the planet gearing. The teeth on the inside actually need to take the full force of turning the actuator screw.
I got semi far in the comments and didn't see it mentioned, but this looks like an office place actuator for moving desk tops up and down. We got a couple at the power plant I work at for that purpose at our operator desks. The signal wires send a height feedback to the controller.
Perhaps you could do a video showing the difference between a ball twister and a ball screw. My plant seems to have both but they are used for wildly different applications.
Hey man great channel!! I've got a few 12v automotive linear actuators made by Dakota digital with the controllers for them also if your interested in tearing them apart. Cheers, Daniel
The nylon gears only have to overcome frictional losses on that sweet sweet thread. So they aren't under too much stress. Being nylon they are going to be alot quieter than powder metal gears just not as wear tolerant. I wouldn't bank on the resembled part locking up as a failure for AVE to reassemble it correctly. It was in the bin for a reason.
AvE, I know this isn't the forum or the subject, but I just have to get this off my chest. I'm a long time subscriber and lurker so I hope you'll forgive me; I never wanted to believe that my brother was stealing from his job as a road worker. But when I got home, all the signs were there.
Since you don't need it to be back exactly to factory specs, bore an access hole so you can assemble it, then plug it (maybe one of those flat threaded plugs they use on electrical boxes).
If the nylon gears are stronger than the maximum load produced by the drive motor at the point of stall, then they are fine. They don't carry the holding loads (that is taken by the brake assy behind the thrust bearing). The reason that actuator sounds so nice is BECAUSE of those helical cut nylon gears!
