Thread: Fletty's new shed WIP ....or is it a retrospective??

Originally Posted by bryn23

I don't know to much about Electric Machinery Motors, because as long as they start and have enough power i don't even think about it.
but wouldn't it just be easier and cheaper to buy a single phase motor to replace the three phase motor and just rewire it, than having to add a VFD and rewire?

Well now you'll get me started.

If you want to just use the VFD just so you can generate the 3 phase power and run a 3Phase machine in stock format then your suggestion is definitely worth considering.
However VFDs offer so many other benefits that really makes them worth considering and this is why I have replaced perfectly good single phase motors on several of my machines with a 3 Phase motor and a VFD.

The most significant benefit is speed control at the turn of a knob. a VFD significantly reduces the number of belt changes on machinery and you are much more likely to drive a tool at a more correct speed rather than suffering the wrong speed. And, as indicated by Fletty you may be able to sidestep annoying vibrations by changing the speed
The ability to run machines at low speed is a good way to see if a belt or a band is tracking truly without it almost instantaneously hitting its max operating speed

Then there is soft starting, as well as limiting current rush this also reduces wear and tear and turns some so called 15A machines into 10A machines.
Conversely, there's the ability to stop machinery far faster than the usual coasting to a stop, and at an additional cost machines can be made to stop on a dime in an emergency.

Then there are jog capabilities (incremental rotation) and reverse directions at a flick of a switch - ever had a big drill bit jam in so hard you cannot take it out of a workpiece without some effort, reversing at slow speed is a very easy way to do this.

The VFD readouts useful motor parameters including the RPM and current - these will tell you about the load your motor is under well before you hear or feel these effects.

VFDs and 3Phase motors will probably eventually take over as the standard motor and speed controller in many machines and appliances. For example Asko washing machines use a cut down VFD and a 3Phase motor. Machines like lift doors, pumps and AC units are all starting to use VFDs.

Replacing a 3 phase motor with a single phase motor is not always as easy as it sounds and even replacing a single phase with a single phase has issues where an replacement motor is no longer available or you want to use a used/cheaper/better motor.
Typical problems involve, mismatched physical size, footprint alignment, and shaft/pulley sizes.
If the 3 Phase motor is convertible to 240V 3Phase at the connection box, sometimes its less work to hook up a VFD than to fix the above problems.

Unfortunately none of my conversions have been that simple but once I had one machine with a VFD I could see how useful they were and is why I have converted most of them to run this way.

However, unless you really know what you are doing with mains power and have the gear to correctly test new setups I don't advocate rolling your own.
Having some knowledge of what can be done can be useful when you discuss things with your sparky.
Not that I found many sparkies know that much about VFDs anyway although this is slowly improving.

The young sparky I bought a used 4HP 2stage 70L 3Phase compressor from said he was selling it because he had moving into a house that did not have 3Phase. When I asked if he had heard about VFDs he said "VFD what's that". Then I asked him why he didn't just replace the 3P motor with a SP motor? He said he had thought of that but then showed me his new $150 2HP 30L compressor which he had just bought as a replacement and said a SP 4HP was going to cost him $300 and a small compressor was good enough for what he did in his shed, which I suppose is fair enough. At the time for $200 he could have bought a 4HP VFD converted the motor and had a much better compressor.

The other older sparky I bought a used 1HP 3Phase motor from (for $35) said he had taken it off a used WW lathe and replaced it with a new single phase motor that cost $150.
When I asked him about using a VFD he did not know what I was talking about.
The irony was I used that 1HP 3Phase motor to replaced the perfectly good SP motor on my lathe .
At the rime the $AUS was doing OK so the VFD for that cost me $120 and for $155 I had a variable speed drive lathe.
The SP motor from my lathe was eventually used on a metal cutting BS on which the motor had started to overheat.

Originally Posted by bryn23

I don't know to much about Electric Machinery Motors, because as long as they start and have enough power i don't even think about it.

but wouldn't it just be easier and cheaper to buy a single phase motor to replace the three phase motor and just rewire it, than having to add a VFD and rewire?

Originally Posted by Chris Parks

It might be but the three phase motor and VFD has advantages over the single phase motor. The VFD can be utilised to control motor speed and reduce the current draw on start up and that can avoid having to rewire or replace switches, sub boards etc though it is not applicable in this case. The VFD can also be utilised to brake the motor to a quicker stop and in a situation where motors have long run down times stopping it earlier can be an advantage.

Chris is absolutely correct in terms of the overall benefits that a VFD can bring but each situation will need to be reviewed on its own merits.
In this case, and I haven't explained it fully before, I hit the SPARE PARTS TRAP! I bought the machine knowing that it was 3 phase so I knew that I was going to have 2 choices:

• Replace the 3 phase motor with a single phase (new motor cost $280) OR
• add a VFD ($170 to purchase + $100 to bring out star point)

However, to maximise the spare parts and repair potential, the original manufacturer installed a mechanically NON STANDARD motor with a shaft diameter 4mm smaller than standard () and the flange holes 45 deg OFF STANDARD () neither of which were driven by any reasonable mechanical need.
So, my choices then were;

• Reduce the new motor shaft diameter (fully disassemble, remove bearings and centrifugal switch, take to engineering shop = $$$) OR
• increase the bore on the impellor, broach a new key slot (= balance issues + $$$)

So, I was stuck with the old motor for mechanical (only!) reasons which then dictated a VFD AND changing the bearings.
If the installed motor had been standard, then I would most probably already be operating the DC with a brand new single phase motor?
fletty

Thanks Bob and Chris for the low down on VFD and its benefits

Quite a few benefits were pointed out, i can really see how will work in a woodworking machinery environment to machine materials at the right speed.

Being able to reverse a drill press is handy when jammed, that alone would save some belts being damaged.

Although it would be funny to watch some try and cut timber when the motor is in reverse who here has drilled a hole with a batterydrill and not realising it was in reverse


Fletty, i see know why you went down the VFD path, looking forwards to some reviews one its all up and running, i also see you have beaten Festool to the larger dusty market with your flash festool green ratchet dusty for quick removal on the work site

Originally Posted by fletty

However, to maximise the spare parts and repair potential, the original manufacturer installed a mechanically NON STANDARD motor with a shaft diameter 4mm smaller than standard and the flange holes 45 deg OFF STANDARD neither of which were driven by any reasonable mechanical need.

This is a common problem when motors are swapped.

The issue becomes more common when larger motors are installed because invariably the motors have larger diameter shafts so the pulley more needs to be enlarged. Sometimes there's not even enough metal to allow for enlargement so a larger pulley has to be used. This changes the gearing which means changing the driven pulley as well and on it goes.

Originally Posted by fletty

Bessey declined to supply spare triggers, "we don't sell spare parts" and so here is my little stash of otherwise perfectly good Bessey Klikclamps made useless by NON UV stabilised plastic and a lack of a customer service culture. I haven't bought a Bessey clamp since but, if you have, please keep them out of our Australian sunlight!

fletty

Did anything come of replicating the triggers on the 3D printer offer by Evanism a year or so ago?

Originally Posted by apple8

Did anything come of replicating the triggers on the 3D printer offer by Evanism a year or so ago?

Unfortunately no, I think evanism got very busy and it fell by the wayside. I put the wounded clamps up on a shelf above my bench and forgot about them until I needed somewhere to put my growing collection of shooting boards and bench hooks!

fletty

G'day Alan. I would have thought with a reputable company like Besseytools you'd be able to buy spares?? Cheers Peter

Originally Posted by crowie

G'day Alan. I would have thought with a reputable company like Besseytools you'd be able to buy spares?? Cheers Peter

Yes, me too Crowie. When I emailed them I explained the problem, advised them of our high UV environment and offered to pay for triggers that I would happily fit myself. The reply was simply that they do not sell spare parts!
A mate of mine was making a Blue Hills epic out of restoring an old ketch moored in Sydney. He had Klikclamps all over the deckhouse holding steam bent timber in place and they were out in the open for months. When the triggers inevitably broke, these clamps were locked, in place and immovable. He had to smash them off and replaced them with cheaper clamps he bought from (I think) Gasweld.
Anyway, I've moved on now, the verandah now shades that north facing window, I don't buy any Bessey gear, and the World is a beautiful place.
fletty

PS, as a SHAMELESS PLUG for the joinery systems workshop in June (there, I've said it!), I realised today that I hadn't use my Gifkin jig for about 12 months and that relearning how to use it in front of a critical audience would be fraught with ridicule and the throwing of sausage sandwiches from the back row! So I got it out of its drawer, brushed off the cobwebs (on me as well as the jig), cut some scrap timber, used the jig, made an acceptably fitting dovetail.......

image.jpeg

.........and put it back in its drawer!
It was also the first time I've used it under the new dust extraction set up and I was very happy with the result in terms of keeping the jig and router table surface clear of chips. I wonder if I can fluke it again in June?

fletty

Originally Posted by fletty

PS, as a SHAMELESS PLUG for the joinery systems workshop in June ... I realised today that I hadn't use my Gifkin jig for about 12 months ... So I got it out of its drawer, brushed off the cobwebs (on me as well as the jig), cut some scrap timber, used the jig, made an acceptably fitting dovetail.......
.........and put it back in its drawer!

perhaps you need to pull it out again and practice making finger joints?
that is if you have an FJ template

Originally Posted by fletty

...

Now, where can I find ivory ratchet straps.............?

fletty

Tusk Tusk OR an Elephant

Originally Posted by ian

perhaps you need to pull it out again and practice making finger joints?
that is if you have an FJ template

I fear that would be pushing the woodworking gods a step too far Ian. I fluked the dovetail only because the router set ups hadn't been changed since the last job
However, I do NEED to use the finger joint jig on the Gikkin soon because I've now got access to an Incra iBox and I want to do a comparison between the 2. I know that the Gifkin jig will give me 'only' 2 finger joint widths and limited depth and the iBox gives infinite widths and depth to 23mm but at what cost in complexity and set up?
I hope the days are getting longer for you?
fletty

yep, the days are getting longer.

Sunrise today was at 6:34 and sunset is at 20:46, so 14h 12m of sunshine -- not counting the periods of rain / snow / cloud.
plus there's another 1 hr 12 mins of twilight. So we won't really need to use the headlights till around 9:30 PM.

Originally Posted by ian

yep, the days are getting longer.

Sunrise today was at 6:34 and sunset is at 20:46, so 14h 12m of sunshine -- not counting the periods of rain / snow / cloud.
plus there's another 1 hr 12 mins of twilight. So we won't really need to use the headlights till around 9:30 PM.

So with all these additional hours of day light where is the photos of all the wood work being done Gee we are on shorter days and still knocking out wip's