He forgot the combination so I built him a robot. Safe Cracking Robot - Part 1
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- Опубликовано: 10 июл 2024
- My brother-in-law has a safe that he cannot open. I may not be a locksmith, or have burglar skills, but I'm good at engineering so I'm going to build Levy a robotic auto dialer to crack the combination to the safe.
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Chapters:
00:00 - A moment of genius
02:53 - The plan and a 3D model
04:46 - Selecting a motor
05:29 - Replacing an unknown connector
08:58 - Why do I need stall detection?
10:25 - Connecting the motor driver to the microcontroller
14:23 - Finally making progress!
15:58 - Assembling an adjustable chuck
18:14 - Testing the auto dialer on a cheap safe
19:52 - Hard coding the combination
21:06 - Byte Sized Boot Camp Announcement
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Развлечения
I usually give myself a treat when I get something right. This guy is GENIUS, since he gives himself a treat for each wrong answer. I am nearly 60yrs old and cannot believe I have been doing this wrong the whole time.
Give yourself a treat
Whoa. I'm in for a while lot of treats!
Einstein and Tesla both said that they were geniuses because they saw failure as just a solution for a different question
No one saw Tesla's failures. Except Tesla which he examined in his minds eye. He stated that 99% of his prototypes were mentally visualised. Only when he saw it working via his extreamely rare gift of biological AR. Would he build a physical model.
It is said, most worked as predicted 1st time.
As a mechanical engineer I'm cringing but also loving the process and ingenuity. Well done on all fronts. Hope this goes viral.
As a locksmith, same!
How about doing it the old fashioned way. With a doctor's stethoscope?
Electronics Technologist and Locksmith. Same.
That was the best plea for Patreon patronage that I’ve seen. It worked. I immediately went over and signed up to support you. Might even clean out some contributions I’m making to creators I don’t really follow any more and swing those dollars your way.
I would surely patreon him if this would come out...
I saw the LockPickingLawyer safe cracker video a while ago, and have been interested in the build process of a DIY alternative ever since! Great video, can't wait for part 2!
I hope he posts to github too
But why doesn't Lockpicking Lawyer defend homosexual special rights ?
@@benjurqunovwut
I saw the same video. The LPL said the "robot" depended upon the sloppiness of the dial settings. (E.g.: the number 80 will also "work" for 79 and 81; it might work for 78 and 82.)
Just a small hint. If you give some heat to the connector "case" when you are trying to remove it, it will come off really easily. For heat you could use a heat gun or like a hair dryer. You don't need too much of heat to melt the solder.....just that the plastic just starts to slightly soften.
Great suggestion
You are doing everything exactly how i wouldve tackled this project. i loved every single second of it and it was even educational. im excited for part 2!
Such a cool project! Can't wait to see the second part!
Love the storytelling in this!!
Have you calculated how much time it will take for your auto-dialer to try a million different combinations? Odds are you won’t need to try all one million, but.
Retired R&D, EE enjoying this. So many things can go wrong!
I bought a expensive safe with a electronic keypad that took 4-digit number to open. Yep, I forgot my combo. I had bought it from a local company about 4 years earlier. After much begging and proving I bought it, the owner talked me through a secret way to sequence through numbers that opened it. Then, I just had to set the 4-digit number as you would normally.
Makes one wonder if a tumbler type has any such secret way.
Consider using a (heat) pressed threaded insert (PEM) on the 3D printed parts to reduce the chance of movement from stress!
Wow awesome stuff. Can't wait to see the next steps here!
looking forward to part 2!
He should have taped the paper with the combination to the top side of one of those fan blades on his ceiling fan. 😆
It's funny I came across this video because in my math class we are leaning about calculating all possible combinations. Like I was literally watching my online class videos on permutations at the same time I clicked on this.
So much suspense. I want to see that safe opened!
Man this is so cool! Haha! I love it! Amazing work, Zach
Awesome video can't wait to see the next part. If it takes a few seconds to test each combination, it will take you a few weeks/months at most to find it. Doable if you're willing to wait!
Love this so much! I actually just bought a house that as a built in gun safe and the old owner doesn’t know the combo (honestly the biggest selling point for me, the realtor thought I was nuts because I spent like 30 minutes looking at the safe and about 20 min on the rest of the property)😂. The door is locked open and I could easily open the back up but what would the fun be in that. Ever challenge is an opportunity to learn something new and its rare that one this exciting comes along! as a mechanical engineer turned electrical engineer I am trying to come up with the coolest way to put all my knowledge to the test and what you are doing is almost exactly what I had in mind. I’m probably the least experienced in programming side and I have always found that process to be the most maddening and rewarding when I figure something out. so now’s a good time dig in and work through the issues. Can’t wait to start pulling out my hair. Super exciting I will stay tuned to your project!
For kicks, you should try cracking the safe the manual way.
be aware that the robot he is building will spin the dial so much, that it may ruin the dial by wearing it out.
PART 2!!! Please! Hahaha, I can't wait!
Great stuff. For removing connectors like that I use low-melt-point solder. Mix it into the existing joints and it'll remain liquid long enough to remove easily.
i work on cnc s all my life i can relate to your frustration and joy nice video !!
Excellent video
Loved this video. Thanks for sharing. Nice T-Shirt too ;)
Loved the video. You got a new subscriber!
One potential problem might be the jaws loosening or slipping off over time, a potential fix would be to have a set screw for the lead screw as well, so you tighten the jaws onto the dial and then tighten the set screw to give it a bit more resistance to loosening off. It might not be a problem that becomes immediately obvious, but if the safe cracker is running for hours it might become an issue then, and you don’t want it to fail hours into trying to crack the safe, you may have to start from the beginning again.
Another potential solution would be to have some kind of elastic band to wrap around the jaws, just to give them some force holding them together, maybe you could even insert a spring between the jaws to keep the pressure up.
Very cool! I'm also not a mechanical engineer but you have to make due with the tools you have at your disposal. I'm sure you will get to buy cool tools later on and continue to grow on your channel. Great work.
Looking forward to part 2
If this guy makes gecko skin, or attempts invisibility tech I know what hes really up too
part 2 all ready please lol
Your solder work is on the cold side. Use a dab of rosin flux lightly on your connections when flowing the joints. Great project, you are a smarty pants...
Great video thanks.
For the stall detection: I would not look at a threshold of the load value but calculate the derivative of the load value (e.g. how fast it changes, simplest form last value - current value) and go against a threshold of the derivative with the stall detection. In case of a stall you have a large negative derivative and that threshold should be relativly independend of a lot of motor and application conditions.
I'm somewhat confused about this "stall." I guess there is something about the combo lock I don't understand.
Wow. The algorithm recommended this to me, im glad to have found this channel before it blows up, kudos.
I've been making videos consistently for 6 years, it's more of a slow burn!
brother in law calls back "I remember my code!"
As fas as I remember, there was some nice algorithm for generating a minimal sequence of overlapping combinations. That is the shortest sequence of numbers that contains all possible length-k combinations of numbers within a given range.
incredible plea for patreon funding. im sure every machinist who watched this immediately joined
Thank you! Evidently not many machinists are watching this video! However I did have one or two people sign up because of my pitch and I'm grateful for them!
I am glad you are not a mech engineer. Your electronics is top-tier tho.
very interesting project! one thing though. most combination locks start the opening process by spinning the dial two or more turns in the opposite direction to reset the wheels. Personally, I think you might want to give cracking the lock by sound and feel. It's often not that difficult with these inexpensive combination locks.
Nice project.
I have a question.
Why do we take load value “0” for stall state?
Can’t we use other values such as 10~20?
There is a 50/50 chance for position error with a load value of 0.
Yeah I would go ahead and code to stop motor when it sees "very heavy omg what is even happening right now?? load" and not necessarily riiiiiiight at stall. with variables in su of course because ain't no way I'm gonna go back and forth from bench to environment and back to figure out what the value is.
I wonder if a very sensitive accelerometer or maybe even a MEMS microphone could be used in a similar way to how they sometimes show safecrackers in the movies, with a device to listen to the safe. If the accelerometer or microphone can pick up sounds or vibrations from the internal mechanism of the safe, maybe it could make safe cracking a lot faster.
For removing connectors, you can get an heated solder sucker or a desolder station with a automatic vacuum pump. So you don't have to destroy the connector you're removing.
A copper braid will also help remove that last bit of solder.
I would have promised him you can open the safe, 1e6 combinations, its a finite number. Good choice on de-soldering the pins one by one. I wonder what data an accelerometer or load sensing might give regarding the lock mechanism state. Those logic analysers are super helpful. I hope you can buy a lathe, just a small one, that groove was upsetting. Great video. seen auto dialers in other videos but this is a very nice close in . subscribed.
No, it simply gathers three disks one by one, then rotates the lot to the free position.
Lyrics: Tobacco Road
"Bring dynamite, and a crane,
blow it up, start all over again ..."
@4"47 - I though I was the ONLY person to have a roll of Scott Tissue on my bench. It's what I use for my nose instead of tissues.
amazing video! got my Subscription and i cant wait for part 2. thankfully it wasnt an all digital safe he got locked out of those are the WORST. wishing you luck you get the code within 20 min of starting.
OMFG U REELY NEED UH LATHE! Thanks for the video! :)
Depending on the lock, you might be able to exclude a number of permutations as some locks specify that you cannot have one number within a certain range of the one before such as +- 10.
Since that stepper motor has that "load" value I wonder if it could be made to "feel" the little stops that happen when you go past the right number like human safecrackers do instead of just brute-forcing.
Now we are talking, Boston Dynamics style. Copy humans, then do it a whole lot better. This is a job for the yong dude who makes dart boards & basket hoops you can't miss.
Safe auto-dialers are NOT a nondestructive entry technique -- the wear on the combination mechanism from using one is significant, and the wheels, gate, and bushings need to be replaced after using one.
Looks like the RUclips algorithm is forcing you to the created second part of this video as soon as possible))
dupont connectors can fit on almost any pin, good to have a kit of those.
In the past I've had a lot of luck pulling off the connector housing and sliding a new housing of the same pitch over the pins, side stepping any need for desoldering. I think this would've worked here, a trick for next time.
Exactly, I would sooner modify the plug or make an adaptor than risk voiding warranty on a new controller.
It looked like your jaws were slipping on the dial on slow when it changes direction so on fast that would be magnified
Also on the more expensive safe lock the combination has to be dialled in within a very close limit.
If you are out by a small amount it may not open
For mounting it to the safe maybe an angled sheet from the floor or side of the safe if you don’t want to drill holes but magnets alone may also introduce movement in the motor unit..
In no way criticising and don’t want to offend
I Just want to see you succeed in this project
I think I would build in a way to actually clamp it all to the safe in addition to sticking it on with magnets just to ensure it doesn't shift at all while it's working. You mentioned close to the end where you might have allowed your hand to turn some while it was dialing in the combination. It would be a shame for it to shift just a hair while it's working and go through every possible combination without finding the right one
As someone who is in the trade and having successfully manipulated well over 1,000 safes over the last 35 years, I have dealt with both of the safes that you show in this video. Unfortunately unlike most modern safe comb locks, with both that Sentry and that Field &Stream safe, the dial will not come to a stop indicating that correct code has been entered and the lock bolt has retracted. Which means you will have to try the handle every time a different code is entered. And that would not be quick nor fun.
Nice Mr. Rodgers reference
Another tip for removing connectors and other components with lots of pins is to use low-melt solder. You melt the solder on to all the pins then you can use hot air to melt them all at once relatively easily. Be sure to remove the low-melt solder after you're finished though.
Excellent Tip. 8^) a keeper
Hello to Levi. YNWA.
Watched the video on Hackaday. It looks like a fun project.
You'll never walk alone!
For a little bit of backyard turning in reference to your retaining ring grooves without a lathe, spinning in a drill whilst using a dremel with a cutting disk should do a fairly good job.
lol, I was just watching ordinance lab blow holes in hot rolled steel with a 3-D printed shaped charge, and while I recognize that is completely not the way that this person wants to solve the problem, and also requires several licenses he probably doesn’t have, that was the first thing my brain jumped to. 😂
Thanks 😁
what a bummer having to replace the plug to the motor controller! Surely the existing plug was a standard component?
Good job. It’s great when you’re talking - back off a bit on the background “music”
Don’t you need to operate the handle after each combination trial?
I worked for a lock and safe company a very long time ago. I took a class on safe manipulation. I never got to try it other than a few safes in the office. My boss was a fanatic about safes and took the few customer calls we got. I think the method I learned became obsolete because it relied on turning the dial after engaging the handle and measure the arc that the dial is allowed to do. I think most safes now have a simple mechanism that locks the dial from rotating when the handle is moved.
I have a second motor for the handle
You would have to go this on a Group I, but a Group II or IIM comes to a hard stop when the combo is dialed correctly and the dial will no longer turn clockwise.
Great job. I work with robotics for semi-conductor manufacturing equipment. Due to the need for precise position control and collision detection, many robots use motion controllers, instead of steppers. For more hobby level as you don't have the TSMC Intel, or ASML budget, I would recommend building around a DC servo controller with an incremental encoder. Instead of the 1.8 degree or so of many steppers, you can have very fine position control. While a 1.8 Degree stepper does provide 1/2 steps for a 0-100 dial. A DC motor with a 500 line encoder such as an HEDL or HEDS will provide 500 lines of 4 transition resolution, or 2000 transitions per revolution. They run nearly silently. Current sensing can be used to provide direct feedback of torque at all times. A coreless DC motor eliminates cogging to a very fine ripple if you use for example some of the Maxon DC motors. Other options include integrated drive DC servo motors for another precise no skipped steps solution. Some of those solutions are industrial prices, not for the faint of heart hobbyist. Edit, recommend the DC servo driver DCS810 to replace small stepper motor drivers and a DC motor with encoder.
Wow it sounds like you have a lot of experience to draw from! My stepper motor controller has micro stepping down to 256 steps/per step. That's a whopping 51,200 pulses per revolution! Precision is not an issue here. In fact I'll be exploited the fact that you don't need to be perfectly on the combination number to open the safe
@@bytesizedengineering Yes the stepper is a good option when you write your own acceleration curves. Robotics outside the realm of steppers, uses a PID loop, to handle the acceleration, to work given a destination, speed, and go commands. The motion control does the rest for you, even with changing loads. It is an interesting filed if you choose to get into robotics and need the speed and precision for material handling. The field often uses brushless DC motors, as well as coreless brushed DC motors. Encoders control the rough position, while laser infromettry controls fine position for areas requiring sup micron positioning, such as lithography. Most of the stuff I work on the incremental encoders land a linear motor within 1/2 micron, with fine positioning handling the final nano meter positions.
I'm curious why you didn't contact the motor manufacturer to get the part number for the mating connector. It's appalling that they wouldn't list that on the web page or datasheet.
I know, I searched every datasheet I could find and it wasn't listed anywhere. I should have asked their tech support for a part number, but I had already pulled off the connector and replaced it!
As much as you spend on a good stepper motor, you’d think they’d throw in the connector. I was kind of surprised that 3D printing wasn’t involved in creating a custom connector so as not to void the warranty.
@@bytesizedengineering Check page 6 of the Datasheet, under order codes. Kind of an odd place to hide it! www.trinamic.com/fileadmin/assets/Products/Drives_Documents/PD-1076_hardware_manual_hw1.10_rev1.03.pdf
@@natelarson2800 Dang! I hate when that happens. I checked stock hoping to find none available thus saving dignity. Only 18,000 available at digikey.
@@natelarson2800 right there in the datasheet. Perfect place to put it. I used to supply industrial solutions and the datasheets and manuals were almost always very thorough. It's where I went to find the answer to any questions I didn't know. RTFM.
The datasheet on digikey calls out the connector as JST EH. It does look pretty similar to ph though
Curious about a few things (Not critiquing, there's definitely more than 17 ways to skin a Stepper Motor)
I am not an engineer, I just do a lot with 3D printers, and thus, a lot with stepper motors
I think that going with the NEMA 23/34 with the driver already built into the board may have caused you more problems than you would have had with getting a driverless NEMA 23/34 and putting the driver on whatever board you chose. Especially with having to resolder and resize the gap for the JST. You might have had to choose a different board, but some drivers also have the stall detection pre-baked into the driver. May have been easier to configure?
Alternatively, you could have gone with a Closed Loop stepper, which would have provided position feedback. Maybe i'm underthinking how difficult that would be to have the board saying "Expected position X, received position y - Stall detected" with the other equipment you used, though. I do know it's possible to have the device "correct" itself to make expected position match actual position based on the closed loop.
Past that? All of it is fascinating and I can't wait to see more.
I think you make a lot of really good points. Switching to a different driver is pretty simple. I'd have to do some research to find a suitable driver, but it wouldn't be that hard to switch it out
Worth having a look at the TMC2209 not sure on your amperage requirements as it’s only 2a but has all the features you should need for a project like this and can usually be obtained for a reasonable price.
Sweet content! Any idea of the song name at 20:05?
I wish i had this little machine, got a second hand safe a month or two back, never got a combo hence why i got it free. Been trying to crack it since then.
7:37 just use a solder sucker, and remove the solder pin by pin.
Easier to just use your dremel on the connector i think and leace the pcb intact
You can desolder each pin on the connector and pull them through as the plastic shroud melts.
Im a safe tech and need a manipulation aid made. Its just a digital dial position sensor that can detect .1 - .9 throughout the dial.
Great video but I have a question.
Mathematically is it better to try combinations randomly and store failed ones or is it better going up sequentially? Obviously depends on the correct combination being more random than sequential.
it's best to use feedback from the pawl/handle of a combination lock to determine if you are in a true or false gate.
In Amherst center (in Massachusetts) at the Chinese restaurant “oriental flavor” there is a safe that they have never been able to open since the place was a bank a really long time ago.
How many tries and time allowed before triggering the safe's self destruct mechanism ha, good luck cracking !
you will be needing a new mechanism inside that safe lol
FYI-your dialer could NEVER "dial" open a direct drive like the Sentry the dialer systems are made for dialing to a stop retraction point of bolt work. The direct entry never stops in that fashion.
I had to laugh at the connector part of this video. All of my projects run into this kind of roadblock.
I'm so glad someone can relate! Most of the comments are about how I'm doing everything wrong.
I have that yellowstone hoodie! I wear it all the time. Very soft and comfortable. (also, cool video :D)
It's so comfortable!
My 3-year-old also has the same hoodie
I so need the code for this. Got one that came with our house that really really needs to not be locked anymore lol
My trick for removing such a connector is to heat one pin at a time, let the heat soak for a second and while still holding the iron on, i grab the pin from the top of the connector with pliers and pull it out quickly. This is possible because the plastic softens. Works almost every single time.
Ever heard of solder wick? Looked like you were removing that connector the hard way.
I want to know how the product is made and whether it is sold abroad
You could have 3d printed a brace to hold dupont connectors in their fully inserted position. Like just allow the cable through not the connector. Good job replacing the connector tho
7:21 Not saying it’s the best way to accomplish it, but the way I do it, if I can’t get the plastic piece off like you mentioned, is to add a little extra solder to the pins, slide an Xacto #11 blade under one end of the plastic like a wedge, then run the edge of the fattest soldering iron tip I have along the pins making contact with as many pins at once as I can. Eventually it will kind of “pop” and move up a bit. Then I push the blade in a little further, repeat, and move the blade around until there’s a big enough gap I can get another wedge or lever tool under it. One downside I’ve ran into is the pads on some cheaper pcbs will peel up, presumably due to the excessive heat and prying. But, that’s pretty rare when it’s a good quality pcb.
I thought about trying that, but decided against it ultimately. I'm sure it would have worked
I usually just replace the plastic shroud, no soldering necessary. You just have to be careful not to bend the pins.
Just out of curiosity is it such a good thing that your BIL owns guns if he thinks its wise to put the combo to a safe INSIDE the safe? Of the 20 million different places he could have hidden it either in his home or on his person he chose to hide it in the safe.
is this a brute force machine or will it detect gates?
OMG the gold inside! lol
It hurt to see you file down that pandrive motor lol
I remember from the movies, that the guys cracking the safes used stethoscopes. As the safe mechanisms are not perfect, they usually produce a faint click when passing a correct number. I'd also expect some clicking in other positions. Either introduced intentionally by the manufacturer, or just by other imperfections of the mechanisms. But that would fairly reduce the amount of combinations to try. Assuming just one try per second (that seems pretty fast) the brute-forcing the combination would take up to 11 days, so - about a week if you're lucky. Using a microphone to put some "suspicious" numbers first in combinations could speed up the process significantly reducing it to hours, if not minutes. I think a program could be better at detecting anomalies than an untrained person. Coding the anomaly detection algo could take less than a week, so - I would be tempted to try it.
It would have been nice if he tried on a decent lock rather than a consumer POS. A S&G Group II would be a nice start, followed by a group 2M, the later having false gates and a cam on the hook. There is a trick where you can cycle through all allowed final numbers without re-dialing the first two. And getting it to work on an S&G Group II is hopeless.
Safe to assume the pre-soldered pins would not slide into the new connector with its pins removed? I've done that with several connectors. that had the wrong shell interface but the correct pin size.
I guess that would mean you would not have to remove the pins and clean out the holes on the PCB. But you would have to pull each pin out of the plastic housing. I hadn't thought of that. I probably still would have done it the same way
Greetings, I'm a mechanical PE doing something very similar to a safe I was given (without the combo). I also chose to use a stepper with a trinamic stall guard driver. I've got the dialing logic down but was struggling to register a stall. I'm using a tmc2209 which may not be 1:1 with your integrated stepper. Would you be willing to provide some sample code just relating to stall detection and identify the hardware you are using?
I'm using a TMC 1076 motor driver. It has a UART interface with TX and RX signals running at a 9600 baud rate. I used a USB to UART converter to connect the motor driver to my computer. The TMC IDE recognized the hardware and started talking to the device. I set up the stall guard parameters and watched the data that was sent in between the computer and the motor driver.
For my hardware, I'm using an ESP 32 microcontroller which also has a UART interface. I sent the same "get motor load" command I saw in the IDE to the motor driver and got a response. From what I can tell out of the 9 Byte response, the 6th and 7th byte contain the motor load. When that value gets close to zero there is a stall.
I picked this driver set up because I thought it would be the easiest way to detect a stall. Admittedly I was very wrong. It was very difficult to get to this point. It's a very clumsy solution to the problem. I will probably switch to some other driver and encoder setup to detect stalls in future versions.
@@bytesizedengineering Thanks for a quick response! Looks like it's time for me to invest in a logic analyzer. I picked my driver because they are common on 3d printers with sensorless homing. I also assumed it would be an easy implementation. I tried an iSV57T-180 integrated dc servo motor, but couldn't get the alarm to be sensitive enough to trigger reasonably. If you are going to abandon the trinamic stall guard route, maybe look into a closed loop stepper motor with an open loop driver as an easy way of getting an encoder output.
I'm looking forward to part 2.
@bytesizedengineering
ruclips.net/video/5xvXnc9eTGA/видео.html
I was able to get my stall detection working with your pointers, other's libraries and a little more RTFM. I'm quite pleased with my setup now.
I have the same lighted push button usb hub :p
@ 11:46 U start with a value around 216;... if that never drops below say 150... At all speeds...
Then use 150 as a stall threshold... Long B4 it looses steps...
It's not that simple. Reading the values is very noisy so they have to be filtered and averaged.
@@bytesizedengineering yeah you'll also have to adjust the threshold depending on the safe's dial and how you fix the motor to it (how much and for how long it dampens while moving and when it reverses direction and so on...) Maybe once in a while you can also press a button and it stops so you can check it goes to a predetermined number to make sure it's on track. Checkpoint daily, then if it's lost steps at some point, readjust and repeat the day .
I do not think that hub will stay in alignment with that shaft with just a jamnut. I think at the minimum you will need some adhesive also. Adding some flats for the grub screws would probably be a good idea too. The stepper motor will get quite warm and that heat will be conducted down the motor shaft where it will loosen the hub via either thermocycling or plastic deformation. But it will probably work well enough to get the rest of the design working, just not allow really high acceleration...
3D printing that part was not my first choice. I had planned on making it out of aluminum, but this is still a prototype. That's another reason I need a lathe!
I assume you're going to code it to take advantage of poor tolerances? For example if one number is supposed to be 91, either 90 or 92 would probably do the trick. That alone gets you to 125k tries instead of a million cause you only have to try 50 angles per number instead of 100.
Yes, I have a few ideas that may get me down to only 10,000 possible combinations
Nice vid. That connector needs a 9 pin JST EH female connector btw mate.
How come my parametric search on DK didn't come up with that!? I think the EH series are 2.5mm pitch, and I need 2.0mm pitch
Opto isolator would be good
yeaaaa really should look into getting a mini lathe. aint toooo pricy