3 Phase

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Woodythepecker

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As i am interested in getting a 3 phase planer/thicknesser i am trying to find out what options i have to power it in my workshop.

I know that there is something called a inverter/converter that allows 3 phase to be run on a 1 phase system, but i have been told that this set up reduces the power of the machine?

I heard somewhere that i could get 3 phase from the old electric board but it would cost a bomb, is this right?

Are there any other options?

I realise that some will question the wisdom of taking this route, but after looking at a number of second hand machines of the wadkin, startrite, scm, minimax, felder etc variety, i believe that there are much better bargains to be had. On top of that these machines are built for the pro's and so will take a lot of stick.
They also come with a lot of accessories that were big buck options when new, such as digital and powered thicknesser's, table saws that turn 360% on the spot., power feeds on spindle molders to name just a few.

The only trouble is to get the table saw and planer/thicknesser i like i am going to have up the amount i budgeted for them from £2500 to nearer the £5,000 i mentioned first. It means waiting a little longer for some other tools, but thats life.

Many thanks

Woody
 
Woodythepecker":2ru2x7fi said:
I know that there is something called a inverter/converter that allows 3 phase to be run on a 1 phase system, but i have been told that this set up reduces the power of the machine?
Dunno. Why not ask someone like Axminster who should, as they sell them?

Woodythepecker":2ru2x7fi said:
I heard somewhere that i could get 3 phase from the old electric board but it would cost a bomb, is this right?
Apparently so :shock:

Woodythepecker":2ru2x7fi said:
Are there any other options?
http://www.team.net/www/shop-talk/hm3phase.html Don't ask me if it work though.

There's lots and lots of information available; Google is your friend. :wink:

Cheers, Alf
 
Woody...

If you're gearing up to do this commercially in a stand alone shop...it may well be worth while to check out the cost of a 3 phase mains hook-up; like everything else in the world it has swings and roundabouts... but for serious machinery, it's the only way to go...

If however... this is a hobby, allbeit a serious one, lower your sights a little and stick with single phase...
 
Woody

If you are a pro then get a workshop with 3-phase pre-installed.

If not then stay well clear of 3-phase kit as both options you mention will cost more than a Sheppach P/T and Tablesaw!

Invertors are very inefficient and you will be much better off buying kit with a single phase motor.

If you are doing this as a hobby, why are you considering very expensive over-the-top, large commercial kit when there is a very wide range of single phase kit to suit every budget that most pros use anyway?
 
Alf wrote:
Dunno. Why not ask someone like Axminster who should, as they sell them?

Oh, i just thought that by asking the question on this forum it might help others (no matter how few of them there are) who may be thinking of going down the same road as me.

Alf wrote:
Apparently so

As there are a number of Pro's on this forum, i thought that someone might have come across this before.
Many thanks for the Google link, i will use that next time.


Midnight, thank you for your input, i will bare that in mind.


Tony wrote:
If you are a pro then get a workshop with 3 phase pre-installed

As i have said in my last post i already own a workshop so unfortunately this is not a option.
Yes i am a pro, and after working as a cabinet maker for a good few years, i have finally decided to use my skill to fill my own coffers and not the bank account of the company i work for. Obviously i have not given up my job yet and i won't do until my workshop is up and running. Hence the reason for the questions i have asked.
You would think that using these machines day in and day out i would know what to buy, but it isn't like that because the machines that i use are big industrial ones with 7hp, 10hp, and even 20hp motors.

Tony wrote:
If you are doing this as a hobby, why are you considering very expensive over-the-top, large commercial kit when there is a very wide range of single phase kit to suit every budget that most pros use anyway?

Over-the-top? Bit much isn't it Tony. On my "Cast Iron or Aluminium" post you did not think that spending £5,000 on a table saw and a planer/thicknesser was "Over-The-Top". Your only concern was whether to buy a planer/thicknesser over separates. So what is the difference here? If it is alright to spend £2,000 or £3,000 on a phase 1 machine, why not spend it on an even better 3 phase machine?
Alright if i go down that route i will have to spend extra to have 3 phase installed, but as you said these professional machines are more accurate.

Even if it was just a hobby i would go for the best that i could afford, and i have always been the same. If this did not matter why doesn't the Aston Martin owner buy a Skoda instead?

Tony look at it this way. How many members on this forum have wished that they could afford a new "Felder" table saw, planer/thicknesser, or even combination machine? I do not know about you, but i am sure if they admit it there will be quite a few, and many of these will be those to which woodworking as a hobby. Why would they do this if these were just run of the mill machines?

Even though this will be run as a business i will still be using the shop for hobby woodwroking too. I love woodworking especially using hand tools. My other hobby is restoring classic cars and i will always buy the best tools i can get for this too.

Many Thanks

Woody
 
Hi Woody

Sorry if my post came over wrongly, I wasn't having a go, just wondering if there is any point in going for Wadkin class machinery for hobby use.

I don't think the skoda/Aston analogy is realistic though as my advice was to go for Sheppach etc class kit which you will find in hundreds (thousands) of pro workshops and will work perfectly well for a very long time. I do not see Sheppach as 'skoda'.

Clearly as you intend to make a living from this, it makes sense to go for well built kit that will last.

One point I would like to raise is that pro machines such as Wadkins 4 side thicknessers are not more accurate than circa £500-1000 kit, they just have much faster feed rates. I know this to be true as I have been involved in research on Wadkins kit (my university had close ties with them for years) with a view to increasing the quality of the cuts as I posted here a while back.

If I can be of any help with the 3 phase side, then please feel free to drop me a pm (it is an area I know a fair bit about).
 
Woody,

Been lurking around your thread. Just an idea but what about having a big bandsaw as a primary resaw rather than a large table saw? Could it save a lot on waste - particularly that expensive hard stuff? and have a much larger resaw capacity if you initially chose not to invest upfront in 3-phase. Could be v.useful for veneer/laminate bookmatch work etc and with a sliding carriage attachment you could buy (smallish) feature timber such as yew, pear,apple etc in the round, dry and resaw it yourself?.

I reckon you're dead right to be looking hard at 3-phase, particularly if you're confident your fledging business will expand steadily. If you've got the space and a 3-phase line running past your property, (and a business plan), just do it mate!

Just a thought.

Ike
 
Okay, I don't know about Woody but I'm confused. Time and again the suggestion has been given "if you have the space, old Wadkin and the like could be the way to go, and 3 phase stuff is very cheap" or words to that effect. It's got to the point where I say it myself, just 'cos I know if I don't someone else will. Are we now saying it isn't a good option? Or merely it's overkill to get the top of the range s/h 3ph stuff? I thought the gist was: reasonable size 3ph + inverter/converter = less £££ than new Scheppach/Jet etc single phase for a better bit of kit. Is this not so? Have I, and others, been mislead all this time? Or have I merely misunderstood. :? Clarification required. :roll:

Cheers, Alf
 
Alf....

for the likes o' thee an me, running a moderate sized 3 phase tool on a single phase supply & inverter is fine i.e. the machine would never see more than occasional use, making it easier to live with the inefficiencies and losses caused by the inverter.
If however, the tools are destined to be pushed hard for longer periods, a dedicated three phase supply is the only way to go for a couple of reasons. Firstly, the economics of the supply; you get more bang for your buck...unit costs for an industrial supply are far lower than domestic charges per kWh. I'm pretty rusty on the 2nd reason, but if I remember my apprenticeship lessons, a high current single phase motor hooked to a domestic supply can cause probs with noise induced onto that supply. This can cause probs with other equipment connected to that same supply i.e. wireless & telegraphy equipment. The last I heard, the electrickery boards imposed a cost penalty if your equipment caused such probs. That's why they (the supplier) would prefer heavy machinery to be run on seperate industrial circuits, typically three phase.
 
Alf,

For a single machine (or maybe two if not used concurrently), a 3PH convertor is a compromise solution to run a bit of cheap S/H 3 phase kit and in that context may be economically attractive compared to single phase kit.

In the context of a complete workshop, technically however it wouldn't be avery good compromise since (i) the power available through a convertor is relatively very limited compared to that of a proper mains 3 phase supply, and particularly so for power hungry machines such as P/T's of typically 5HP or more. So it could be a real ball ache switching plugs between machines all the time. (ii) There are technical issues with the performance of convertors and power efficiency, none of which I pretend to understand, only that it matters somewhat. Good convertors cost a lot and a mains supply, although costing a lot plus some more gives reliable, industrial strength juice for industrial machines.

Ike

Ike
 
If you are only buying 1-2 machines, can you not switch out the motors and replace with single phase? It can't be that expensive surely?

Adam
 
Right. Thanks, chaps. So what you're saying is "it depends"... :lol: Now why doesn't that surprise me? :roll:

Cheers, Alf
 
I don't know much about 3 ph bit in my view an industrial machine is not particularly more accurate but it retains its settings almost indefinitely.The heavier components are great for repeat operations but not a great advantage if doing a lot of one-off work.My son-in-law operates a large shoe repair machine on a rotary converter(5 hp) and he has had no problems at all athough it did cost about £800 without fitting.
 
Tony, i wasn't comparing scheppach to a Skoda. My sister has the TS4010 and she has found it to be a very good machine.
The point i was trying to make was even if this was just a hobby i would still go for the very best that i could afford. Its the same as the car owner, even if he just wants a car to get him from A to B why should he have to settle for a cheaper car (the Skoda) when he can afford the very best (the Aston Martin)?

Many thanks for your offer of help with the 3 phase, I will take you up on this.

ike, i have been looking at wide troath bandsaws which i want for resawing/book matching etc, but i must admit i have not thought of getting one instead of a table saw. I will certainly look into your idea. Many thanks.

Alf, it is very confusing isn't it? It is even more confusing when you speak to the dealers and they all say something different. This is the reason that this sort of forum is vital. Yes now and again you will still get conflicting advice, but this is from members who don't have an axe to grind, are not trying to get us to buy there product, and best of all there is always someone who's been there and got the tee shirt.

Again Mike thanks for your input. I did not think that it would be as easy as just pluging a inverter/converter into the mains. It certainly seems that the only way to go is to have 3 phase installed.

Can anyone answer Adams question?

Cheers

Woody
 
Sorry Noel i must have been writing my post when you sneaked in and posted yours.

It looks alright. I do not know what his reserve price is. It would be a bargain for £300.

Many thanks

Woody
 
Woodythepecker":2ng2yxcu said:
Can anyone answer Adams question?
Cheers Woody

Answering my own questions.... I wonder if it's the risk + time factor of it. Nobody wants to spend a few hundred, + delivery on an old machine, only to find it can't be adapted. Furthermore, you need to find a local engineering firm to make some kind of adaptor ring if the bolt layout is different, which takes time, along with gauging the motor size needed. By the time you've spend a few days sorting that out, the "cheapness" of it is not looking to be so attractive after all.

My thoughts anyway.

Adam
 
If yuo're contemplating converting a 3-phase machine back to single phase bear in mind,

(i) why was it built with a 3-phase engine in the first place - answer is GRUNT. Big machines - heavy bearings, heavier rotating mass =more inertia to start etc etc.

(ii) Starting a powerful single phase motor will require a VERY robust supply. So if you factor in the cost of strengthening the supply on top of the cost of a single phase motor, (plus any other mods), will it still be an economc option?

(iii) From (ii), theres a risk that if you go down the 1-phase conversion route, the voltage fluctuation that may occur on the feed to your property may be at detriment to your neighbours (a common example is using a single phase electric welder at high current). Advise you check first with your regional electricity company.

Ike
 
Woody,

re my hypothetical single-phase solution;

I wasn't suggesting a big bandsaw would totally replace a table saw, rather that then, a normal "trade" rated tablesaw (just for example say a Scheppach) would then be perfectly adequate for further cutting of the primary sawn stock.

Ike
 
I don't know if this is of any use but this is a reply I wrote for The Woodworker when asked about a specific type and power of 3 phase machine to run off single phase.


I want to run a three phase 3hp saw from a single phase supply. There seem to be 3 choices, a new motor (and starter I presume), an inverter, or a converter. What do these choices offer in ease of use, smooth running and last but not least cost?
Any advice gratefully received.
Yours
Josephine


Hi Josephine, you have quite a few choices but I am afraid none of them are particularly cheap.

You haven’t said what make the saw is but the first port of call is to the manufacture or importer; they may be able to give you specific information relating to your saw and hopefully provide you with the necessary parts to convert it.

Some 3 phase motors can be relatively easily converted, by rewiring the control panel and fitting a new switch unit. If you look in Yellow pages under Electric Motor Repairs you should find several firms, specialising in motor rewinds who could advise; alternatively they may be able to supply you with a replacement motor. If you do decide to go for a new motor you may have to increase the motor rating in order to get the same starting and running torque.

It is possible to convert single phase to three phase with a Static or Rotary Type Converter. The Static converter is the cheaper option (£470) but these have several drawbacks namely; each time you turn the saw on you have to turn the boost up on the converter, then manually adjust the load. This would be completely unacceptable in a professional workshop and, for a machine which was constantly being turned off and on, would drive you mad. Also they should not be used with aluminium bodied motors. Rotary converters are a far better option, in that they work completely automatically and no adjustments are needed, but they are more expensive (£775.50)

Converters are only about 30% to 40% efficient, so the load from your supply will increase two fold at least. 3hp = 2.23kW so you are looking at about 5kW; it will need its own dedicated supply from the consumer unit fed through a 32A mcb.

One final option would be to contact your electricity supplier and find out how much it would cost to have a three phase supply installed. They would give you an estimate for free, so it is worth asking. It all depends how much work is involved; if you were very lucky it could be the cheapest option.

Prices of the converters were from Axminster Power Tools 0800 371822 http://www.axminster.co.uk/


Thanks to

NMA Agencies (who now support Kity machinery)
Axminster Power Tools technical support
The electricians at Novoserve Trade and DIY Forum http://novoserve.no-ip.biz/
 
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