Here’s a tip for using holes saws in thick metal: touch the hole saw onto the metal so it scribes the perimeter of your hole. Then remove it and drill 4 small holes (at 90 degrees) around the perimeter right through your material. The outside edge of each hole should be aligned to the outside edge of the perimeter. Then resume cutting with the hole saw. This allows for the chips to be pushed out through the four holes and prevents them building up and causing heat and damage to the saw. Also use cutting fluid. And then go and buy an annular cutter and never use a hole saw on thick material again 😂. Great videos btw.
The little holes on the outside, do you mean drill them so their centers go through the scribed line, or their outside circumference, putting the hole on the outside of the scribed circle?
@@albertogregory9678 Little holes should not poke outside the perimeter of the big hole. So drill them inside the big hole, with the perimeter of the little hole up against the perimeter of the big hole, from the inside.
Quick tip. If you have aluminum welded to an insert, soak it in lye water. Lye will dissolve the aluminum and won't effect the insert or steel cutter. Works great for files too.
Hey mate, a tip when drilling through anything thick with hole saw, but works especially well on steel. Drill a small hole in the path of the circle you're cutting. When drilling through thicker material, as soon as the cut is deep enough to cover the hole saw teeth, the chips have nowhere to go. The teeth will get clogged and you just end up rubbing instead of cutting.If you drill a hole first, the chips will be able to exit the cut through the bottom, and you wont have to pull the hole saw out to clear the chips every few seconds. Faster cuts, and less rubbing keeps your bits sharper for longer.
Good tip mate I spent some time trying to cut though steel with a 70mm hole saw, but couldn't get over 5mm in. Maybe i cut down 3mm with the hole saw, then i'll have a grove to guide a jobber bit.
little tip for cleaning cutting tools with aluminium welded to them: lay them in a solution of Lye (sodium hydroxide) for some time, the NaOH dissolves the aluminum right away without hurting the cutting tool. And please give this VFD some air to breathe. It might not be a lot of heat to feel, but it accumulates. And while it might not decrease it's power, it will surely affect the VFDs lifetime.
Another thing with electronic heat is that what you feel is far far away from the actual part of the component getting hot. So even if it does not feel hot it could be very hot at the source.
Two points of contact for rigidity. The base to the bench (of course) and the motor to the wall. It has made a significant improvement to my converted drill press/mill. Can’t see why it wouldn’t work similarly in your situation. The centrifugal forces in that bigger motor is getting everything else to rock-n-roll. I will be very interested to see what you come up with. Luv y’ work.
@@autumn5592 Of course the motor travels with the head. There might be a quill, it's probably longer than you are and still woefully ineffective. This isn't a knee mill, nor a drill press. Have either of you ever even been in the same room as a mini mill?
Yes inductive losses go up with frequency, but if you are only doubling line frequency, there is no issue at all: the VFD waveforms are much higher frequency anyways, and your motor is fan cooled and finned, so I would have no worries going even higher than 2x if necessary.. Just watch the torque requirements and take shallower cuts to keep the currents low, as it's I^2X, so even if the reactive losses become much higher, they are still small compared to the current squared.
Seconded. It's fine as long as you aren't trying to run it at 20,000 RPM or something, then it's more the structure of the rotor flying apart which is a problem.
What about the motor bearings though? I'd imagine there's a potential for overheating them leading to highly accelerated wear if they're the bushing type.
in fact 1400rpm and 2800rpm motor have the same base, the only difference is the wiring. So 1400rpm motor will run fine at 100Hz. I even ran 2800rpm motor a 6krpm on my mini-mill, but it was a small motor (63 frame).
Really looking forward to your rigidity improvements. I think you'd love an inexpensive plasma cutter. I've had mine for 3 or 4 years and it's still just fine. I hope I didn't just jinx myself.
Actually Aldi have a Plasma Cutter on sale at the moment for $299. It might do the job for you? You will need a compressor to provide the compressed air for the Plasma Cutter. Mark from Melbourne Australia
I just got my first lathe and a couple of days before that got accepted to a machine based highschool. I have had a lot of interest with machines since i was really small. The interest was then growing after i found "this old tony" then i gound your channel and now i have applied for that school and managed to get my dad to buy me a little lathe. Thanks
Field weakening with the VFD is no problem. However the torque will decrease and the efficiency will suffer a bit. But when you set up the current and power limit correctly in the VFD it is absolutely fine and standard practice for induction motors.
A modification that I definitely need to do to my mini mill, the lathe has a 3hp 3 phase motor on it, and it is far more usable than previous. I'll be taking inspiration from you, thanks for sharing. Cheers from the UK.
I have a mini-mill, I ended up fitting a 750Watt sewing machine motor to it. Much better than the original puny DC motor. It's an adjustable brushless servo motor, cost AU$176.99. Do a You Tube search for it. Goes up to 4,000rpm, I bought some toothed belt pulleys and can spin the spindle up to 3,500rpm - which is a bit high, the original top speed was 2,500 and the spindle gets very warm running over that for a long time so I changed the ratio for 2,600rpm and am very happy with it. Loads of torque and variable speed. Bought a spare motor as a back up, just in case...
Great video, thank you. I have had a Sieg x3 mini mill for many years now. It has the exact same 1hp brushed motor and controller as yours. I got about 7 years of use before the controller died and like you was horrified at the cost of a replacement board. I did keep my motor and just replaced the controller with a £20 one from eBay. It has worked flawlessly but now seeing this, I wished I had replaced the motor too.
If you're using a hole saw to drill through steel, just barely start the hole so that your circle is marked, then drill a series of 3mm holes around the circumference to create a sort of dotted line. Then your hole saw will chew right through it. Those 3mm holes give the hole saw chips somewhere to go.
I've drilled 20 and 25mm steel and 304 stainless with 60+mm holesaws using a technique similar to this. Predrill the pilot hole and drill 3 or more Ø10mm holes so that the outside edge of the 10mm hole ends up under the holesaw track. The extra holes allow the swarf to drop out. Lots of neat cutting fluid, run it slow with plenty of down pressure.
@@evanbarnes9984 I've seen shade tree mechanics pack differential gears with sawdust to take up the slack space caused by wear on the gears. It works for a while, and is technique usually performed to unload a problem on the next owner.
I can recommend Suttons “Venom” cutting fluid. I was sceptical but it really works to make drilling and tapping easier and you can buy it at Bunnies. I can also recommend the Metabo WEPBA 19-125 5” / 125mm angle grinder. They’re not cheap at around $499 but, buy once, cry once and they have a lot of safety features. With a rated 1900 watts they also have the power of a much bigger grinder. That’s 700 watts more than your new Ozito and boy do you notice it. With so much extra power the blade doesn’t slow down so cutting and grinding is much faster. The difference is incredible. I bought two of them after a serious accident with a Makita. I hope this helps, Cheers Stuart. 🇦🇺
Blimey that’s one powerful grinder. I looked at the makita at Bunnings and it was less than a 1000w. For what it’s worth the Ozito is powerful for the price. I do love me some Sutton a cutting fluid, I use Sutton a cutting paste and it works wonder too. Cheers
I feel your pain, I used the same parting tool insert for months then recently broke three inserts and the tool holder on the same project in a day. In hindsight I think the first failure damaged the tool holder.
Just a tip from a 12 year Millwright, when zip cutting don't press hard. Just keep enough pressure to keep the disc from chattering and sweep the entire cut back and forth steady for the deep cuts. Your discs will last ages longer. Gentle as you can be, let the disc and tool do all the work.
most of the time it isnt any issues to run a good quality motor up to 80hz for long periods of time - tiny tip: when milling aluminium - use denatured spirit as cooling(available at any paint shop),stops the cutter to clog up
Remember Endmill size IS gearing. (I had to learn this mistake). Run the machine 100% rpm/power, use smaller diameter end mill to get right surface speed. I went from preferring 12mm cutters to 6mm. Buy long shank for those tall sidemilling ops. They are also like 1/4 the price.
Ive always thrown a thermal camera on a board thats pooped the bed. 90% of the time I find the issue, but you've done right with upgrading that nice machine
I ended up putting a 600 watt sewing machine AC servo motor and control on the mini lathe after the board died, $120 fix, stupid board was $250. Much more power although now the lack of rigidity is really showing especially when boring. Great video thanks.
I did quite the same on my machine (BF 28) last year and I would never go back ! I can drive the motor between 4 and 115Hz. and as my machine has 2 gears I can use it from 80 to 5.000+ RPM, with a bunch of torque at low speed. Huge improvement that should be done up from the beginning
Love the upgrade. I did a similar upgrade but I used an Ariston washer machine motor. Three phase at 195v and coupled that to a cheap Chinese vfd. Works very well. Now to do my lathe. Slightly larger motor and vfd ordered for the mini lathe. Love the vids.
Haven'f done much of aluminum machining but our teacher, in the year stick and stone, told us to use denaturated alcohol as coolant so the tools won't gunk up.
Yes I have heard someone say something similar. My understanding was that it was a puck of casting alloy that i was starting off with. But what alloy it is I don't exactly know.
I did the same upgrade to my Sieg X3 years ago. I also fitted a gas strut to balance the Z drive (it's now CNC'd). Filling the column and base with epoxy granite helped with the rigidity. Interestingly, I saw a Ryobi ad just after your drill crapped out. Unfortunate timing.😮
Man, this hits too close to home lately. Breaking tools is a major bummer and lately I've been having about the exact same luck as what you've had in this vid. I'm pretty sure you know this already but just in case: I have 2 suggestions. Firstly, ryobi has a massive warranty on their cordless products. I always end up somehow magically burning up my 18v tools around 2-3 weeks before the warranty expires. At least here in the states we can just take them back to home depot and straight up swap the drills and such for brand new ones (not sure if you have that option on your side of the equator but its worth a shot?). The second has to do with your smelting and casting... don't quench in water like... ever. Always use oils and preheat your quenching fluid as much as possible first. You will reduce the chances of warps and stress fracturing your parts by doing so. Ive been watching your content for some time and I have to thank you for all the time you've put into these. I'm an old geezer but you and a couple other machinist channels have taught me so much I cant even calculate it. Cheers and thanks, my dude!
Just for info ( perhaps useless) in my working career I was an electric motor specialist and did many “weird” tests and experiments. You can safely run a 4 pole motor at 100hZ without much loss of torque, however a 2 pole motor starts loosing torque at around 150% full speed ( 50hZ running at +/~ 75hZ)👍 By the way keep going with your very interesting videos👍👌😁
Also regarding use of a VSD , if you run at lower speed you need to think about cooling , I solve the problem with a “PC fan” mounted on the motor cowl
7:54 a higher frequency is no issue. The frequency printed on them is just a measurement for the optimal conditions it was designed for. So you'll look at more heat loss at the same power output, if you run it with a higher frequency. So as long as you monitor the temperature of the motor, you're fine. I would expect 50% more energy-loss if you double the frequency - at least. So if the 3 HP motor is designed for say 800 W heat loss (75% efficiency). So to keep it within the 800 W heat loss, the casing is designed for, you can only run it at 2 HP continuously, that is.
Hi Artisan, as always: Great vidoe on a great channel. Thank you for that! But one suggestion from my side. I think if you have not enough tork in your 16mm drill maybe your belt is too small. You could double up the pulleys and use two belts to transfer the whole 3HP to the tip of your drill. ...just my idea. Greetings from Germany Sascha
I had a lot of money tied up in Ryobi One tools, then after another Li battery failed, I decided to find something more suited to my needs. Eventually, I went for Milwaukee and haven't looked back. Gave all my old stuff to my son, who is only a light user, so we are both happy. At the end of the day both Ryobi and Milwaukee are owned by the same Hong Kong outfit.
Brother, you need to use cutting oil and go much slower (RPMs) for a hole that size. And use more tool pressure. Clear the chips more frequently. PS: that's not a timing belt. It's a drive belt. Unless you guys call it that down under. Good work though.
@@artisanmakes You can fashion a makeshift "drill press" by tack welding a rod or bar vertically in front of the hand drill, attaching another bar horizontally to the vertical such that it pivots up and down and then fastening the drill to the middle of the horizontal bar and guiding it with one hand and pulling down with the other on the horizontal bar. Might not have helped here, but it's a good trick to have in your tool bag.
Mate, you desperately need a drill press. It will save you a ton of time and effort and reduce tool breakage. I would also recommend getting a set of annular cutters rather than using a hole saw. Alternatively, you can drill some holes around the diameter of the holesaw to allow the swarf to fall through. It will prevent you from overheating the holesaw and breaking teeth off on swarf. Also, when machining gummy aluminium, you can touch up the carbide on a diamond hone to give it a sharp edge. Also, give it generous servings of WD40 while cutting it and this will help reduce chipwelding.
I swapped my spindle pulley sleeve when I converted to a belt drive. I found the spline profile I needed on aliexpress and just turned it down to fit my bearing.
Rigidity issues limit the effective use of HP.. My Bridgeport mill was built in 1948. It only has a 1/2 HP motor, yet it performs with excellence. As a mentor in the machine tool trade told me many years ago "rigidity is a key factor in all machining operations"
Replacement boards are available from 3 party sellers for less than $50.00 US here and there are many better DC controllers for that motor that will probably fit in that enclosure
I hope you include some air vents for your VFD. Without proper air exchange for cooling almost all of these electronics will fail prematurely. Even with how cheap the VFD are, it’s more that it’s a pain in the ass to deal with. I wouldn’t leave heat dissipation up for chance by way of the machines mass, even a small vent on the underside of your new control board cover will help tremendously over none at all. If you really want a definitive answer, then just stick x1 thermocouple to the inside of the VFD case (to read the air temp immediately surrounding the circuitry) as well as one for the inside of that enclosed area (to read ambient air temp for VFD operations).
You might take the board to a electronic repair shop (make sure they know what the board goes to) and see if they can't figure out which part popped, it might be a cheap fix.
Feeds and speeds also apply to holes saws and drill bits. You ran them too fast for steel. If your cutters ever get gummed up, use lye or drain cleaner to dissolve away the aluminum. Also, use kerosene, or even better coconut butter as a lubricant to prevent the aluminum from sticking.
@@artisanmakes Oh, yeah. They were cordless. It's why I still have my 30 year old Makita drill. I can dial it down to a crawl and still have lot's of torque. The Brushless are supposed to be better in that regard as well. You can clutch them down.
For sure the hp line of Ryobi is a lot better that the compact line of one+ Get a 3d printer, it would had made the job of getting a pulley much easier (and trust me, printed parts are much stronger that what usually people give credit for)
When you go above base frequency you will trade speed for torque, however comparing the torque curve of this motor to your last motor id suggest even at 2x base speed torque will still be greater
I started to have concerns over rigidity when it appeared to take less effort to move the machine than the significantly oversized metal for the new motor mount.
I HAD BOTH THE MINI MILL AND MINI LATHE, LOVED THE MACHINES BUT DUE TO THOSE CARDS BURNING ON BOTH WITHIN MONTHS I GAVE THE MACHINES BACK, I MISSS BOTH THOSE MACHINES
@@artisanmakes I actually came here to say all this :) You don't need a four jaw chuck for your two horizontal mills - just chuck up the drill and mount the metal on the cross slide ...
I hope that motor is inverter ready. I’ve converted several machines. I always take out the old motor, even when it’s three phase, as they aren’t suited for variable speed use. You can seriously damage a standard three phase motor using a VFD as a speed control device. At low speeds my motors can be used down to 6 rpm. It has torque compensation from 6 hz to 60 hz and constant speed from 60 to 120 hz. This is important as a three phase motor will lose serious torque at low speeds, pull a lot more current, and eventually burn out. Problems at high speeds as well. If you hear a whining sound as the speed is increased, increase the modulation frequency. The manual should give the recommended frequencies. Be careful of vibrations. VFDs really don’t like them. I mount mine with anti vibration mounts. Also, you can’t put them in close areas, you need room for good air circulation and heat removal. Talking from a lot of experience with these.
@artisan makes ... look into the settings for your VFD, there should be a setting that lets you modify the torque values at low frequencies and even boost the torque throughout the rpm range.
Speaking of inserts made for aluminium... TiN coated inserts like the one shown are notorious for aluminium welding to them. Its better to use uncoated carbide for this. Also, if you squirt a little bit of isopropylalchohol on the workpiece will medigate this effect and lubricate for a much better surface finish. But please do this in a ventilated space only. Also: i love your channel - keep up making good content
Recommendations, and I'm sure you've heard this hundreds of times :) Some annular cutters for the lather and a bandsaw. I want to cry every time you pull out your hacksaw.
if you want the vfd to last longer it needs some ventilation, not dissipating heat kills electronics .I wonder if the original control board would of lasted longer with better ventilation?
btw, the type of VFD you have there is designed for running things like fans, it drops the voltage as your RPM decreases to maintain constant current across the coils for maximum longevity of the motor. Thats why the torque is so poor when trying to drill large diameter holes. Two things you can do to improve the performance, swap out the VFD for a sensorless vector drive unit, these provide way more torque at lower rpms and can recover if the motor begins to stall. Next would be to replace the silly 3HP motor for a 1 1/2HP one with 6 poles as apposed to 4. Due the the lower rotor mass the max speed is far higher than the plate speed, that number is simply what the motor will run at when connected directly to 3 phase power while you will find that the same motor model family with 2 poles has a plate speed of 3600rpm with 150% overrun margin so you actual self disassembly speed is like 6k+ RPM lmao.
Whilst this motor wasn’t my first choice, I don’t want to make it out like I have little torque at low speed. It’s quite a lot for what it is. I am sure we can do better but I’m over sinking money into motors and drive units
@@artisanmakes haha, that's always the way. I ended up changing to a gear head machine myself so no more torque problems. But you will end up running into trouble with annular cutters with that setup, you simply wont have enough HP at the speeds those work at, for everything else you should be okay.
