I found a PWM speed reduction module in the workshop and ran the Hilda unit through it to see what happens at an even slower armature speed. It did not cause pulsing as can happen, so it does do the job reasonably smoothly on that brushed motor. Basically there's no advantage/point using one as the torque just evaporates below 17,000 rpm (minimum speed as supplied). The motor will only run above 10K and the power is useless until 17K. So basically they have reduced the speed (as supplied) to the minimum practical amount. I played around with the unit and tried drilling at various speeds. Interestingly while the no load minimum speed may be 17K, once you start drilling (I used 1/8") into hard steel, the speed drops drastically to a level you would normally use, so drill burn isn't an issue provided you apply sufficient pressure. As cutting load will increase with drill diameter, I expect you could even increase drill speed/torque and once it starts cutting the same thing will happen. Not ideal, but certainly it appeared to do the job with smallish drills. I have drilled brass and alloy with it on the lathe with no problem when I made the Stirling engine, but not steel. So it can do drilling, but not in a controlled fashion like a proper geared drill. Cheers Rob
Hi Rob ! I've had one from Dremel and it never sounded good when running - low or high speed doesm't matter and now it's dead ! I think the speed control was killing it because when run on reduced speed it got very very hot and in the end I think it simply tousted the speed control. Now I'm trying to convert a Broun Food blender using the parts from the tousted Dremel ;-))
Rob, this is very helpful. Over here we see motors rated in horsepower mostly. According to Jeremy Fielding's channel 1 hp = 746 watts. That puts this grinder just over 1/2 hp in our terms or what I can relate to. That is a quite strong little grinder. Thanks for the video. :-)
Hi Glenn, Yes, that's correct. You can convert Amps drawn to Watts or HP (or the other way round). It's all relative. This is a gutsy little unit, but it is direct drive and can't compete with an equivalent geared drill at low speed. However, it is perfect at grinding speeds and will match a genuine TPG on most things for small diameter stones. Glad you enjoyed it. Cheers Rob
Agreed, the Hilda is really a die grinder and too fast for drilling most materials. Because it has a chuck, people assume it’s a drill. Air die grinders typically come with a collet and nobody thinks they’re a drill. ;-)
Yes, totally agree. The chuck makes it a lot more versatile regarding grinding accessories, but drilling is really limited to small diameter bits and soft metal/materials. Cheers Rob
There is no measurable runout in the chuck/bearings after all the work it has done. Runs fairly quietly compared to an air grinder. I wouldn't call it "rattly". No worse than any angle grinder. I would NOT use it for wire brush work as that puts a lot of load/drag on the motor and being direct drive it will overheat. Rob
Thank you Rob. Some of my power tools for example will say they are a 10 amp or a 7 amp motor or so. They sometimes don't give anything else. How is this converted into Watts to get an idea of its strength? I really do appreciate your channel. Thanks
Hi Glenn, There are plenty of conversion sites on the web. This is just one: www.rapidtables.com/convert/power/hp-to-watt.html You can easily convert most things these days. They just use standard formula and apply as required. You can also get an upgraded Microsoft calculator for your PC with scientific and conversion factors. It just upgrades the calculator included with every version of Microsoft. www.microsoft.com/en-us/p/calculator-plus/9wzdncrdhjwd?activetab=pivot:overviewtab This is totally free and very good. Cheers Rob
Hi Chris. Yes, you can only really use small diameter drill bits in soft materials. An external speed controller would help but then you still have the issue of no gear reduction. It's really a die grinder (excellent at that type of work). Cheers Rob
Hi Rob I have watched some of your videos and I would like to get into lathe work I am looking at the lathe you recommended best bang for buck METAL LATHE & STAND - 610MM BC would you still recommend this lathe for someone with no experience and best value in Australia? I am in QLD and would really appreciate your advice thanks m8.
Yes, it's a lot of lathe for the money and has all the features you need. The ALG320G in comparison costs more, is a bit smaller and has no quick change gearbox. I certainly wouldn't go any larger than this for a beginner as you could make a mistake and things get ugly much more on the big ones. I'd still get the best bang lathe considering what else is out there and the money. Cheers Rob
Thanks for posting this Rob. After watching this i did a few tests on my own Hilda. On the lowest setting it tops out at about 16000, so similar to yours. I then connected it up to my meaty variac and dropped the voltage a bit. Even a small reduction in rpm results in almost no torque. Which, having now read the other comments i see you discovered. I use it for cross drilling on the lathe but only up to 3mm in drill bit size. As you said, if you use a fairly heavy feed rate the speed drops right down anyway. I will keep a look out for a suitable geared motor that i can use with the flexidrive for more control. Cheers, Alan.
Hi Alan, Yes, that pretty much sums it up. I wondered about a variac but the PWM results didn't give out much hope torque wise. I'm a bit annoyed that the BG spec is so wrong. There are often errors, but this one is really bad. I suppose they go on what the supplier gives them. Oh well, that's life. Cheers Rob
@@Xynudu On the plus side it is an excellent grinder, cutter, polisher and for the price i don't think there is anything to touch it for those sort of jobs.
Yes, I really like it. Way better than anything else out there and for the price. But I really wish BG would get their act together on this stuff. I've pointed out numerous description errors to them which should not occur. The Bro Inlaw saw mine cutting up some thin springy stainless steel sheet and has one on order. It really is very good at what it does best. Those 75 mm cutting discs work extremely well with it. I use these : www.smithandarrow.com.au/product/cutting-discs-wheels/metal-cutting-discs-wheels-3-75mm-x-1mm-angle-grinder/ I hardly ever use my equivalent air die grinder now. Cheers Rob
It was on AliExpress but then I read some reports that said it was way down on power and could be the 220 volt version sold as a 110. LOL. That explains a lot. I just had a look but couldn't see it.
I ordered one at AliExpress, in 110V for general purpose use including drilling with small size carbide drills in the lathe. The idea being to transfer radially located holes to a final size in a second operation. We'll see what happens on arrival. Apparently I bought it on special at U$28, now is U$58 for the basic unit. www.aliexpress.com/item/BDCAT-110V-220V-400W-Mini-Grinder-Engraving-Variable-Speed-Dremel-Rotary-Tools-Grinding-Power-Tools-with/32898769652.html
I have radially drilled brass with it no problem. But it is definitely too high a speed for steel and drill longevity. Anything soft is OK. This unit is really just a die grinder. Rob
If you live in NA do not buy this thing. I did and 120 V does not work. 0 to 3 the top speed is 0 RPM 3 to 6 it runs but I do not have a meter to measure the speed but I suspect that it runs at half the top speed. If any one knows how to rewire it to run on 120V I would love to know.
I found a PWM speed reduction module in the workshop and ran the Hilda unit through it to see what happens at an even slower armature speed. It did not cause pulsing as can happen, so it does do the job reasonably smoothly on that brushed motor.
Basically there's no advantage/point using one as the torque just evaporates below 17,000 rpm (minimum speed as supplied). The motor will only run above 10K and the power is useless until 17K. So basically they have reduced the speed (as supplied) to the minimum practical amount.
I played around with the unit and tried drilling at various speeds. Interestingly while the no load minimum speed may be 17K, once you start drilling (I used 1/8") into hard steel, the speed drops drastically to a level you would normally use, so drill burn isn't an issue provided you apply sufficient pressure.
As cutting load will increase with drill diameter, I expect you could even increase drill speed/torque and once it starts cutting the same thing will happen.
Not ideal, but certainly it appeared to do the job with smallish drills. I have drilled brass and alloy with it on the lathe with no problem when I made the Stirling engine, but not steel.
So it can do drilling, but not in a controlled fashion like a proper geared drill.
Cheers Rob
Interesting to note that the sticker on the unit itself doesn't even make a claim as to the low speed, it just says "no:25000/min".
Hi Rob !
I've had one from Dremel and it never sounded good when running - low or high speed doesm't matter and now it's dead !
I think the speed control was killing it because when run on reduced speed it got very very hot and in the end I think it simply
tousted the speed control.
Now I'm trying to convert a Broun Food blender using the parts from the tousted Dremel ;-))
Hi Keld,
AHHHHH, re-purposing. What man was always destined to do. He He. I expect to see a video on that some time.
Cheers Rob
Rob, this is very helpful. Over here we see motors rated in horsepower mostly. According to Jeremy Fielding's channel 1 hp = 746 watts. That puts this grinder just over 1/2 hp in our terms or what I can relate to. That is a quite strong little grinder. Thanks for the video. :-)
Hi Glenn,
Yes, that's correct. You can convert Amps drawn to Watts or HP (or the other way round). It's all relative.
This is a gutsy little unit, but it is direct drive and can't compete with an equivalent geared drill at low speed. However, it is perfect at grinding speeds and will match a genuine TPG on most things for small diameter stones.
Glad you enjoyed it.
Cheers Rob
Agreed, the Hilda is really a die grinder and too fast for drilling most materials.
Because it has a chuck, people assume it’s a drill.
Air die grinders typically come with a collet and nobody thinks they’re a drill. ;-)
Yes, totally agree. The chuck makes it a lot more versatile regarding grinding accessories, but drilling is really limited to small diameter bits and soft metal/materials.
Cheers Rob
It's a bit rattly, but good for wire brushing and using up worn down cutting discs. Really doesn't like high loads though!
There is no measurable runout in the chuck/bearings after all the work it has done. Runs fairly quietly compared to an air grinder. I wouldn't call it "rattly". No worse than any angle grinder.
I would NOT use it for wire brush work as that puts a lot of load/drag on the motor and being direct drive it will overheat.
Rob
@@Xynudu Yeah, I let the smoke out a couple of times!
Thank you Rob. Some of my power tools for example will say they are a 10 amp or a 7 amp motor or so. They sometimes don't give anything else. How is this converted into Watts to get an idea of its strength? I really do appreciate your channel. Thanks
Hi Glenn,
There are plenty of conversion sites on the web. This is just one:
www.rapidtables.com/convert/power/hp-to-watt.html
You can easily convert most things these days. They just use standard formula and apply as required.
You can also get an upgraded Microsoft calculator for your PC with scientific and conversion factors. It just upgrades the calculator included with every version of Microsoft.
www.microsoft.com/en-us/p/calculator-plus/9wzdncrdhjwd?activetab=pivot:overviewtab
This is totally free and very good.
Cheers Rob
nice video Rob,see you next time......
Have come to same conclusions Rob... drill burnout potential.
Still got those darned pigeons then :-)
Hi Chris. Yes, you can only really use small diameter drill bits in soft materials. An external speed controller would help but then you still have the issue of no gear reduction. It's really a die grinder (excellent at that type of work).
Cheers Rob
Hi Rob I have watched some of your videos and I would like to get into lathe work I am looking at the lathe you recommended best bang for buck METAL LATHE & STAND - 610MM BC would you still recommend this lathe for someone with no experience and best value in Australia? I am in QLD and would really appreciate your advice thanks m8.
Yes, it's a lot of lathe for the money and has all the features you need. The ALG320G in comparison costs more, is a bit smaller and has no quick change gearbox.
I certainly wouldn't go any larger than this for a beginner as you could make a mistake and things get ugly much more on the big ones.
I'd still get the best bang lathe considering what else is out there and the money.
Cheers Rob
This is one place where getting more isn't seen as a better deal... lol
Thanks for posting this Rob. After watching this i did a few tests on my own Hilda. On the lowest setting it tops out at about 16000, so similar to yours. I then connected it up to my meaty variac and dropped the voltage a bit. Even a small reduction in rpm results in almost no torque. Which, having now read the other comments i see you discovered. I use it for cross drilling on the lathe but only up to 3mm in drill bit size. As you said, if you use a fairly heavy feed rate the speed drops right down anyway. I will keep a look out for a suitable geared motor that i can use with the flexidrive for more control. Cheers, Alan.
Hi Alan,
Yes, that pretty much sums it up. I wondered about a variac but the PWM results didn't give out much hope torque wise. I'm a bit annoyed that the BG spec is so wrong. There are often errors, but this one is really bad. I suppose they go on what the supplier gives them. Oh well, that's life. Cheers Rob
@@Xynudu On the plus side it is an excellent grinder, cutter, polisher and for the price i don't think there is anything to touch it for those sort of jobs.
Yes, I really like it. Way better than anything else out there and for the price. But I really wish BG would get their act together on this stuff. I've pointed out numerous description errors to them which should not occur.
The Bro Inlaw saw mine cutting up some thin springy stainless steel sheet and has one on order. It really is very good at what it does best. Those 75 mm cutting discs work extremely well with it. I use these :
www.smithandarrow.com.au/product/cutting-discs-wheels/metal-cutting-discs-wheels-3-75mm-x-1mm-angle-grinder/
I hardly ever use my equivalent air die grinder now.
Cheers Rob
@@Xynudu Not sure if we can get Smith & Arrow over here but i'm sure there will be something similar.
Does that even have a CE mark/RCM mark? Dodgey.
I wouldn't use that chuck at 27k RPM personally :)
humm, Looked and looked but didn't find the 110v version for use in the states, but the reviews are all very good about it.
It was on AliExpress but then I read some reports that said it was way down on power and could be the 220 volt version sold as a 110. LOL. That explains a lot.
I just had a look but couldn't see it.
Yes it wouldn't run very good at 1/2 the voltage. hahaha
I ordered one at AliExpress, in 110V for general purpose use including drilling with small size carbide drills in the lathe. The idea being to transfer radially located holes to a final size in a second operation. We'll see what happens on arrival.
Apparently I bought it on special at U$28, now is U$58 for the basic unit.
www.aliexpress.com/item/BDCAT-110V-220V-400W-Mini-Grinder-Engraving-Variable-Speed-Dremel-Rotary-Tools-Grinding-Power-Tools-with/32898769652.html
Interesting thanks Rob.
This should give a proper milling device at those speeds.
Did you check the speed under load? I'd wonder what it works out to.
How much load is the question ? Also that would not tie in with the high speed reading, as under load that would also be less.
At low rev setting the torque probably fades away as would the revs
Yes, that's what happens with AC. I doubt these use a PWM circuit to lessen the effect.
Nice video, thanks brother
The only thing you'd drill with that thing is your wallet, for the cost of new bits!
I have radially drilled brass with it no problem. But it is definitely too high a speed for steel and drill longevity.
Anything soft is OK. This unit is really just a die grinder.
Rob
Stuff that would shut thoughts pidgins up, defiantly a tool to respect cheers.
Those pigeons are on borrowed time.
If you live in NA do not buy this thing. I did and 120 V does not work. 0 to 3 the top speed is 0 RPM 3 to 6 it runs but I do not have a meter to measure the speed but I suspect that it runs at half the top speed. If any one knows how to rewire it to run on 120V I would love to know.
I suspect it's a 220 volt unit only.
You could buy a step up transformer, a 500 watt one runs less than $30 USD.
Exactly. Apparently they work very well. Most current ones convert both ways.