Restoration Project Considerations - Any Thoughts??

[Steve 940]

Many thanks Alan & Tannerton,

Such comprehensive information and it really has been so helpful, at least now I may stand a chance of understanding my discussion with my neighbour.

Did look on UK Power Networks and average cost for 3 phase indicated circa £3k+

Cheers
Steve

[Burdekin]

Originally Posted by Steve 940

Hi Alan,

Very valid point, and I am aware I will need to uprate my feed from the main house fuseboard or meter box to garage, my next door is retired sparks with a shed full of cabling etc. so hopefully he will be able to provide guidance and some heavy cable to cope with start up loads.

Been thinking, as if spraying, I will have compressor running and some largish extraction fans, plus sundry lighting etc so will make sure its beefy enough to cope with those loads.

One of the earlier posts, a forum user had used a phase convert or to run a 3 phase four post lift, but I couldnt really get my head around if that's a good idea or not, so I'll check with my next door.

Cheers
Steve

I have a 3kw phase converter and run the 3phase around my workshop from it for my lathe, milling machine and pillar drill and it works a treat but wasn’t cheap. The multiple compressors sound excessive but it is the cheapest way and think it’s also the best. You also get added tank volume which reduces water in the air. This is the one I have and is excellent: https://www.amazon.co.uk/Wolf-Dakota.../dp/B007VOLOHG they use to be about £250

[Othen]

Originally Posted by Steve 940

Many thanks Alan & Tannerton,

Such comprehensive information and it really has been so helpful, at least now I may stand a chance of understanding my discussion with my neighbour.

Did look on UK Power Networks and average cost for 3 phase indicated circa £3k+

Cheers
Steve

£3,000 would be a fair assumption for installing a 3 phase supply, but it could be a great deal more if the demand and diversity in your local area dictate there isn't capacity on the other 2 phases (from the one you are connected to) at your local substation. At the moment you probably have a 100a domestic supply (if you have a really old 60A supply you are probably stuck), so 1ph at 240v. That means you can have 24kW (about 32HP) of stuff going on at your house. If you add up all the things you have around the house it will come to a fair bit more than 24kW, but you never use them all at once (that is what the diversity assumptions are for).

You are going to add on a considerable workshop. There is no particular need for you to buy any generic 3ph/415v machinery or tools, so the only reason you would need a 3ph supply would be if your demand was to exceed 100A and you could not arrange the diversity to prevent that happening. Unless you have a superfast (22kW) EV charger that is unlikely to be the case, but your electrician will have to calculate how much you can spare for the garage before it starts tripping circuit breakers. Your neighbour will know how to do this of course. The design bit isn't something you can do yourself - it will have to be signed off by a competent person, as will the installation.

I never liked installing power to domestic outbuildings because almost invariably people would have underestimated the costs, often they thought it would be just running a bit of twin and earth from the back of a 13A socket. Quite often people would baulk at the cost of getting a 20A supply to the bottom of their garden for the hot tub (eventually I refused to fit supplies for hot tubs - what a waste); I rather suspected that some ran a bit of twin and earth from the back of a socket after I'd gone - but that wasn't my problem as long as they didn't tell me what they had done.

It is really good that you are thinking about what you need to do now, and not after you have bought the tools.

:-)

[Burdekin]

Originally Posted by Othen

£3,000 would be a fair assumption for installing a 3 phase supply, but it could be a great deal more if the demand and diversity in your local area dictate there isn't capacity on the other 2 phases (from the one you are connected to) at your local substation. At the moment you probably have a 100a domestic supply (if you have a really old 60A supply you are probably stuck), so 1ph at 240v. That means you can have 24kW (about 32HP) of stuff going on at your house. If you add up all the things you have around the house it will come to a fair bit more than 24kW, but you never use them all at once (that is what the diversity assumptions are for).

You are going to add on a considerable workshop. There is no particular need for you to buy any generic 3ph/415v machinery or tools, so the only reason you would need a 3ph supply would be if your demand was to exceed 100A and you could not arrange the diversity to prevent that happening. Unless you have a superfast (22kW) EV charger that is unlikely to be the case, but your electrician will have to calculate how much you can spare for the garage before it starts tripping circuit breakers. Your neighbour will know how to do this of course. The design bit isn't something you can do yourself - it will have to be signed off by a competent person, as will the installation.

I never liked installing power to domestic outbuildings because almost invariably people would have underestimated the costs, often they thought it would be just running a bit of twin and earth from the back of a 13A socket. Quite often people would baulk at the cost of getting a 20A supply to the bottom of their garden for the hot tub (eventually I refused to fit supplies for hot tubs - what a waste); I rather suspected that some ran a bit of twin and earth from the back of a socket after I'd gone - but that wasn't my problem as long as they didn't tell me what they had done.

It is really good that you are thinking about what you need to do now, and not after you have bought the tools.

:-)

A lot of quality old machines are 3phase, if he wanted a lathe, milling machine etc then going three phase now would be worth it but if not then a decent 1phase supply. Needs to be decent though for the compressors and a couple of large exhaust fans.

[Tannaton]

One of the engineers at work bought an old 3-phase lathe from auction and was able to replace just the motor for a single phase one.

[Steve 940]

Originally Posted by Burdekin

A lot of quality old machines are 3phase, if he wanted a lathe, milling machine etc then going three phase now would be worth it but if not then a decent 1phase supply. Needs to be decent though for the compressors and a couple of large exhaust fans.

Ah, that touches a great point, I've been viewing quite a few online spray shop guides, you mention exhaust fans, from what I have garnered I think I need negative pressure within the garage to stop spray going outside, but not really sure how to achieve this in a diy garage with concrete floor.

Much as I would like 3 phase I think I'm sticking with single, and if needed in future I could go down that or phase converter route.

Cheers
Steve

[Burdekin]

Originally Posted by Steve 940

Ah, that touches a great point, I've been viewing quite a few online spray shop guides, you mention exhaust fans, from what I have garnered I think I need negative pressure within the garage to stop spray going outside, but not really sure how to achieve this in a diy garage with concrete floor.

Much as I would like 3 phase I think I'm sticking with single, and if needed in future I could go down that or phase converter route.

Cheers
Steve

This is a great guide to making a spray booth: https://www.hse.gov.uk/pubns/priced/hsg276.pdf

Just concentrate on moving the air and clearing the overspray in a spray room. My workshop I have two big exhaust fans that have filters fitted so air going out goes through the filters. Even with the two big exhaust fans it's no where near as good as a down draught spray booth but it will clear the room and I make sure I keep my air fed mask on until the room is properly cleared and safe. There’s like dead zones even though I have two large exhaust fans. I think an oscillating fan at the other end may help.

I added a second fan but not got a pic. The fans are 500mm axial fan which does about 150m3/min.

[Burdekin]

Originally Posted by Tannaton

One of the engineers at work bought an old 3-phase lathe from auction and was able to replace just the motor for a single phase one.

Yeah you can go that route, single phase motors aren’t as smooth but certainly doable. The good thing about the converter is it’s all plug and play for old three phase machines which I like. You can also go for VFDs for each motor. Not got any pics of the three phase wiring but that’s my converter next to my old M300 lathe and all the other machines run off 3 phase from the converter. Works a treat for me.

[Othen]

Originally Posted by Burdekin

A lot of quality old machines are 3phase, if he wanted a lathe, milling machine etc then going three phase now would be worth it but if not then a decent 1phase supply. Needs to be decent though for the compressors and a couple of large exhaust fans.

That is true enough: there are lots of old industrial machines (which were generally 3 phase) that now have almost no value because they have been replaced with CNC tools. Other factories don't want them and almost no one has a domestic 3ph supply. I have turned down quite a number of fantastic machines local companies were trying to give away for exactly that reason. The supply of those redundant machines will probably dry up in the next 10 years, but I'm pretty sure Steve could still find a free 50 year old lathe or milling machine locally with another 50 years of use left in it, but the downsides are a need for 3ph power and probably no more spare parts if they go wrong.

A large market in domestic supply machine tools has developed for the hobby/home business user, exactly because of people like Steve. Even 2 post lifts are available that only need a domestic supply! If it was me (and it is not, it is Steve), I'd stick with newer 1ph 240v machine tools. Just my opinion.

:-)

[Steve 940]

Hi Mitch & Alan,

Much to think about, one upside in the expected delays in waiting for planning I suppose is that I can mull this one over.

What a set a machines Mitch, not jealous at all

I think you've both made very valid points, and at least Mitch's experience of using converters is very reassuring, and it will enable me to continue the extension to workshop on a standard domestic wiring basis. I will put in extra draw cords from meter / fuseboard to garage though, 'just in case'.

Whilst I love the thought of 'cheap' older 3 phase kit, I do need to really put my sensible head on, space will be a priority.

Alan, yes my brother in law on the farm has a massive 18" wide surface planer circa 60-70 years old, works a treat when running, but he has had several problems in getting the odd replacement part, and when you want to use a machine, you really want to be able to plug and play.

I do have an old Record DIY / hobby combi sawbench/planer and spindle moulder, whilst it allowed me to do our whole house refurbishment, including making our oak kitchen. It isn't the best, half the time you're battling as fences are not exactly true etc. etc.

No right or wrong, but I think I will just concentrate on the basics for the moment, get my project car and prioritise the bodywork/welding and build up my tools/machines as required.

Cheers
Steve