Which converstion would you recommend for my 3 phase graduat

[miles_hot]

I've been digging around and have found 3 companies which offer conversion kits for Graduates:
Speed Genie
LRE
newton tessla

I will post what I've found out around the varous options etc which they offer when I get home as I need to crystalise the information somehow and sharing it out seems as good a way as any

In the mean time some questions for you all:
1) does anyone have any experience of any of these kits (easy of fitment, quality, use etc)
2) the Genie uses a box to house the inverter where was the LRE and I think the NT one put all the bits and bobs inside the lathe - any preference or reasons why one is better than the other?

Many thanks

Miles

 

[Jonzjob]

I'm not sure what kind of conversion you are looking for but would these people be able to help?

http://www.drivesdirect.co.uk/our_products.htm

 

[big soft moose]

I'm not sure what kind of conversion you are looking for but would these people be able to help?

http://www.drivesdirect.co.uk/our_products.htm

good point the prices on this page http://www.drivesdirect.co.uk/Products/ ... ckages.htm are abbout half those of LRE - the only thing is that the LRE set up is tailored to the graduate so there are no probs with fitting pulleyes onto the motor spindle - that may not be the case with the drives direct package

 

[Jonzjob]

I have no connection with DD, but I have ordered and am awaiting the 3 phase motor and converter for my lowly CL1. They were very helpful in helping me with what I needed and wanted. At the moment they are in the throws of 'moving house' to a new setup, but still found the time to get my kit on its way. They didn't have my Imperial size motor in stock, but it didn't take long to get it.

Give them a try. You may be pleasantly surprised?

 

[Finial]

I have the LRE Variturn kit on my Graduate. It works fine, no problems at all. If I did it again I don't think I would put it inside the lathe, it was a bit nerve racking cutting away the lathe body to make room for it.

I fitted a different converter to my other lathe and found the instruction manual very off-putting at first but the wiring actually was straightforward once I studied it closely.

The LRE version doesn't need the converter itself wiring, just the lathe switch connections as I recall.

 

[miles_hot]

I have the LRE Variturn kit on my Graduate. It works fine, no problems at all. If I did it again I don't think I would put it inside the lathe, it was a bit nerve racking cutting away the lathe body to make room for it.

I fitted a different converter to my other lathe and found the instruction manual very off-putting at first but the wiring actually was straightforward once I studied it closely.

The LRE version doesn't need the converter itself wiring, just the lathe switch connections as I recall.

I don't suppose you can work out who did the other conversion?

Thanks for the view on the LRE, I hadn't realised it involved cutting the lathe about, still they have a very good reputation so I guess it's OK...

Miles

 

[paul-c]

i got mine from newton tessla
new motor and inverter and they do the switch unit to fit in the original switch position.
great people to deal with imho.

 

[richburrow]

I am with Paul C
Mine has just arrived and I am waiting for the right moment to fix it in.
I will give you more info as I get it, I will have another look tomorrow evening
Rich

 

[miles_hot]

Thanks Rich - I look forward to the update

Does the inverter have a speed read out on it?

Miles

 

[Finial]

The other converter is an IMO Cub unit. I fitted it myself although when I first read the manual I nearly called an electrician. The quotes I got for wiring it in were horrendous so I studied the manual more closely and it turned out quite easy when i got my head round it. It worked for years but I recently had to replace it, again with no real difficulty.

Yes, you have to cut out lumps of cast iron from the lathe pedestal using an angle grinder to put the LRE unit inside, at least you did back then. They give full instructions. But once done it worked a treat. I would happily get another similar unit but there is no real need to put it inside the lathe.

 

[dickm]

As a matter of interest, have any of you folk with inverters found that dust is a problem? Or are the units sufficiently well sealed not to worry?

 

[OldWood]

I've fitted two Direct Drives inverters to lathes - one a Graduate and the other a Wadkins Bursgreen. I've also done a motor change and controller installation on another older lathe for the local wood turning club - I can't remember the lathe type but it was a Speed Genie controller.

My experience out of all that was that the Direct Drive controllers are good, easy to install and once you've understood the structure of the instruction manual, are very flexible in what they can do. I wasn't so impressed with the Speed Genie in that its programming did not offer the number of adjustable parameters I used on the DD drives, plus I had to frig the speed control to limit the lowest speed - motors should not really be run lower than 20hz or overheating will occur.

As far as motors are concerned, I've fitted one new motor and rebuilt another. The rebuild was to convert the 440v star connected motor ont he graduate to 240v delta connection. I did hesitate in doing this but having fitted a new motor to another lathe, the star/delta re-wiring was by far the preferable task. The motor change involved a lot on the mucky side (plate cutting, drilling, pulley boring, etc).

Depending on your skills, you can build your own controller box or buy one in; don't consider using the controls on the inverter as they will drive you scatty, plus the inverter should be mounted on the wall a bit out of the way of dust, etc.

You cannot get a direct read out of speed as the motor is controlled by the variable frequency generated by the inverter so it shows frequency on its display; with a direct drive such a readout would be possible but on a conversion, pulley ratios come into play. You have to buy a cheap tacho off Ebay and make a calibration chart.

I bought a small rev counter module off Ebay and interfaced it with an optical sensor from Maplin to get direct revs.

Rob

 

[miles_hot]

I've fitted two Direct Drives inverters to lathes - one a Graduate and the other a Wadkins Bursgreen. I've also done a motor change and controller installation on another older lathe for the local wood turning club - I can't remember the lathe type but it was a Speed Genie controller.

My experience out of all that was that the Direct Drive controllers are good, easy to install and once you've understood the structure of the instruction manual, are very flexible in what they can do. I wasn't so impressed with the Speed Genie in that its programming did not offer the number of adjustable parameters I used on the DD drives, plus I had to frig the speed control to limit the lowest speed - motors should not really be run lower than 20hz or overheating will occur.

As far as motors are concerned, I've fitted one new motor and rebuilt another. The rebuild was to convert the 440v star connected motor ont he graduate to 240v delta connection. I did hesitate in doing this but having fitted a new motor to another lathe, the star/delta re-wiring was by far the preferable task. The motor change involved a lot on the mucky side (plate cutting, drilling, pulley boring, etc).

Depending on your skills, you can build your own controller box or buy one in; don't consider using the controls on the inverter as they will drive you scatty, plus the inverter should be mounted on the wall a bit out of the way of dust, etc.

You cannot get a direct read out of speed as the motor is controlled by the variable frequency generated by the inverter so it shows frequency on its display; with a direct drive such a readout would be possible but on a conversion, pulley ratios come into play. You have to buy a cheap tacho off Ebay and make a calibration chart.

I bought a small rev counter module off Ebay and interfaced it with an optical sensor from Maplin to get direct revs.

Rob

I'd be interested in the details of your rev counter

Miles

 

[Anonymous]

Hi Miles,

I didn't need a new motor as mine was dual voltage. I got an invertek all in one unit from here:

http://www.inverterdrive.com/default.aspx

It's a nice unit with the bonus that it's IP55. When I bought it I checked if I could wire it up to use an external potentiometer (speed dial) and they said yes. I haven't tried yet though. I think it was this one that I got:

http://www.inverterdrive.com/group/AC-I ... fault.aspx

Mounted it just above the lathe. For bigger bowls a bigger motor would be nice but I really don't turn enough at the moment to give two hoots.

Cheers,

Dave

 

[miles_hot]

How does one post a table on here?

 

[miles_hot]

Ok, here's some information about the 3-4 options I've looked at. Also my first go at coding a table from scratch so this'll be a labour of love I suspect!

All prices need VAT and delivery added.

Goodness knows why the table has taken to hiding at the bottom of the message - sorry about that. (Mod Edit: good job someone does :lol: CHJ)

I can't really comment on Drives Direct as I've not been in touch with them (I'm put off by the lack of Graduate specific focus). The others have been pretty responsive and free with information, pictures and advice. The first of equals has been NT who has even done my hand sketches of the layout to allow the interconnects to be wired in. I am waiting for follow up responses from the others concerning some of the "unknown" items.

Current front runner is NT due to the OEM switch gear and general responsiveness (and lack of cutting into the lathe)
<table border="1" padding="3"><tr><td> Features and prices</td> <td>LRE</td><td>Newton Tesla</td><td> Haydock / Speed Genie</td><td>Drives Direct></tr><tr><td>Switch Gear</td><td>OEM Plate</td><td>OEM Plate</td><td>External box</td><td>unclear - possibly just inverter?</td></tr><tr><td> Inverter mounting</td> <td>Within Lathe (some cutting required?)</td> <td>External </td> <td> External</td> <td> external</td></tr><tr><td> Options</td> <td> . </td> <td> . </td> <td> . </td> <td> . </td></tr><tr><td>Remote Foot Off Switch </td> <td> ?</td> <td>yes </td> <td> £20</td> <td> no</td></tr><tr><td> Visible frequency read out</td> <td>no </td> <td>Think so </td> <td> no</td> <td>possible (hard to see) </td></tr><tr><td>Able to wire in existing foot switch (on machine) </td> <td>unknown </td> <td>yes (instructions supplied)</td> <td>yes </td> <td>DIY </td></tr><tr><td>Abe to wire in door interconnects? </td><td>unknown </td> <td>yes (instructions supplied) </td> <td>unknown </td> <td> DIY</td></tr><tr><td> Variable ramp speed</td> <td> Selectable (2)</td> <td> yes</td> <td> Selectable (2)</td> <td> Assume so - mentioned only for "advanced" inverters</td></tr><tr><td>Advanced (vector?) control of speed </td> <td>No mentioned </td> <td> yes</td> <td>unsure </td> <td> advanced inverter only</td></tr><tr><td>Remote control pannel </td> <td> no</td> <td>no </td> <td> £50</td> <td>£45 </td></tr><tr><td>Reverse </td> <td>yes </td> <td> yes</td> <td>£5 </td> <td> yes</td></tr><tr><td colspan="5">option 1: invert existing motor (assumes dual power) </td></tr><tr><td> Cost</td> <td>.</td> <td>£198 </td> <td>£229 (from email - web site = £259) </td> <td>£275 for basic, £330 for advanced </td>
</tr><tr><td>Notes </td> <td>.</td> <td>To wire interconnects etc need an exclosure (£49). Is sorting a fully wired in box price </td> <td> . </td> <td> . </td></tr><tr><td colspan="5">option 2: new motor (similar power) - i.e. Imperial </td></tr><tr><td>Cost </td> <td> £470</td> <td>£314.89 </td> <td>£328 </td> <td>£225 </td></tr><tr><td> Notes</td> <td>Seems a very comprehensive fitting kit </td> <td>1hp, existing pulley goes straight on </td> <td> . </td> <td>strongly suspect that the inverter is basic type </td></tr><tr><td colspan="5">Option 3: Upgrade motor</td></tr><tr><td>Cost </td> <td>£540 (1.5 hp) </td> <td>£386 (1.5 hp) </td> <td>£419 (2hp), £519 (3hp) </td> <td> £300 (2hp)</td></tr><tr><td>Notes </td> <td>Seems to be a very well respected kit. Quotes 3 hour fit time. </td> <td>Upgrade = Metric. Changes to the pulley: Motor shaft shorter than pulley (not an issue) - no mention of need to bore out pulley, suggests that motor shaft is different to Speed Genie. Biggest motor = "80 frame" - thus largest option is 1.5hp </td> <td>Need to bore the pully out to 24mm (£25), 2hp easiest of the options. Makes no mention of 2 or 3 hp not fitting Graduate; maybe the external enclosure for the inverter? </td> <td>not specifically for the graduate Have advanced vector control inverters but more (330 plays 275) - strongly suspect package is simple one </td></tr><tr><td>Delivery </td> <td>17.5 + Vat </td> <td>£18 inc VAT, 2-3 days </td> <td>7 days </td> <td> . </td></tr></table>

 

[Jonzjob]

I think that there is still a bit of work on tables needed here Mark? :evil: :evil: :evil:

 

[miles_hot]

not sure what's going on with the table to be honest but all the info I know about is there...

 

[OldWood]

Mark
As someone who has done a conversion on a Graduate, I find some of your table entries a bit puzzling.

I will have to say from the beginning that I've used Drives Direct inverters on my friend's Graduate and my own Wadkins so know that type, and I've also used a Speed Genie (all 1.5hp type) for a club lathe

All inverters can be controlled on their built-in control panel. All inverters can be programmed to use an external switch and speed box. The Speed Genie and DD inverters were identical in their external box requirements which might suggest that all current inverter designs are the same in this area. If someone asked me I would say that such control boxes are in the order of £30 and it surprised me to see you quoting £50.

With reference to 'emergency stop' and 'external stop switches', the DD machines have dedicated ports that could be used for this. The Speed Genie had to have such switches wired in series with the external control box Off switch.

You cannot have 'Visible Speed Readout' as this is dependent on the pulley ratios on the lathe, and you will need to retain the multi sheeve block in order to get the full speed range. Both inverter types I've used had the option of frequency read-out.

Variable ramp up and down existed on both types of inverters I've used.

I didn't look into the advanced control of speed as I didn't see it as necessary for a wood lathe.

What did surprised me most were the prices you quoted. I have an invoice less than a year old in front of me here for a Speed Genie and 1 hp motor for £411. I know that the DD controller for the Graduate was ~£135 also within the last 12 months.

I do get the feeling that you are expecting to buy a package that you can just plug in. No way, Hosee. This a major exercise that will take some time and will require both mechanical and electrical skills and associated equipment. You are, from my knowledge of the subject, making this choice factor far too complex; the control of a small induction motor for a wood turning lathe is a very simple task for any of these controllers which are all designed for much more demanding operations. Whether you go with this one or that one, the amount of work you are going to have to do to install it is going to be much the same so you might as well go with the cheapest.

Rob

 

[miles_hot]

Rob

Many thanks for responding, frankly this is all new to be so your experience and comments are both welcome and probably carry more weight for the rest of the board than my gropings towards understanding .

I've responded to specific comments below however I'll start by saying that all the figures and "factual" statements have come from supplier sites and emails so I'm fairly confident on these. Anything that I'm assuming or "think" I hope I've marked up as such (I'll go and check in just a moment.

I suspect (as you allude in your closing comments) that this is not actually going to be a simple thing otherwise everyone selling one would have converted it, however I am focusing on the suppliers who are know for, and market themselves as, specialising in Graduate conversions with the hope that they will have taken some of the leg/brain work out of the equation - i.e. which motors fit, motor/inverter combinations: are they all the same or do some not match up etc. Time (and my reports back to you all) will tell - hopefully I wont lose my sense of humour on this one

Any road, back to your comments:

Mark
All inverters can be controlled on their built-in control panel. All inverters can be programmed to use an external switch and speed box. The Speed Genie and DD inverters were identical in their external box requirements which might suggest that all current inverter designs are the same in this area. If someone asked me I would say that such control boxes are in the order of £30 and it surprised me to see you quoting £50.

I'm very interested that you found the SG and DD set ups so similar as I understood that the SG setup came with the external box / control panel with the controls on it; I will have to check back with them as all the literature and stuff which I've got from them so far shows a large box (which I assumed contained the inverter) with all the controls on it which you mount either on the wall or I guess off the back of the lathe in some way. They also have the option of a remote control (price a quoted so I guess there's a mark up in play here) which further supports the idea that the pictured box would be wall mounted.
When comparing setups I have looked at the "kit" as supplied by the company. II don't dispute or doubt your statement that all inverters can be controlled directly off their front panel however looking at the size of buttons (from pictures only so a sense of scale can be hard) I suspect that this is not the easiest method of control and hence I assume the supply of more "user friendly" controls - note this is my assumption! As these are supplied by the companies it is these that I am looking at when making the comparison.
In terms of the ability to programme inverters etc I'm again looking at the control panels which are supplied - the ones I've marked as 2 settings are because there is a switch on the panel and in one case at least they state that the inverter come ready programmed using this switch. Again I bow to your greater knowledge and experience on this one as it's all new to me. Nice to hear that I will / should be able to tweak settings if I feel the need.

With reference to 'emergency stop' and 'external stop switches', the DD machines have dedicated ports that could be used for this. The Speed Genie had to have such switches wired in series with the external control box Off switch.

Very interesting news on the DD - I will have to do more digging with them. The SG bumph makes mention of a foot off switch which can be connected via a jack - the only one to make this claim. I suspect that the method you state for the SG will be similar to the set up for the NT box.

You cannot have 'Visible Speed Readout' as this is dependent on the pulley ratios on the lathe, and you will need to retain the multi sheeve block in order to get the full speed range. Both inverter types I've used had the option of frequency read-out.

Ah, I see - I did mean to show "speed" as I was very uncertain that this would be anything about speed given the pulley situation - I will amend the table to show Frequency - thanks for clearing that up. Looks like there'll be another little project to get a shaft speed read out...

I didn't look into the advanced control of speed as I didn't see it as necessary for a wood lathe.

Fair enough, I'm a bit of a gadget freak and if something "advanced" is available for roughly the same price and "bog standard" I'll be drawn to advanced. Sad, but at least I'm admitting it which is possibly the start of a cure... In all seriousness I'm merely reflecting all the information I can find - that way it's there for people if they want to use it.

What did surprised me most were the prices you quoted. I have an invoice less than a year old in front of me here for a Speed Genie and 1 hp motor for £411. I know that the DD controller for the Graduate was ~£135 also within the last 12 months.

As mentioned before all prices are either off the supplier sites or from emails they've sent me (noting a discrepancy when I found it). your experience is a little worrying as it suggests that I'm missing something on the SG. My DD figures for the inverter only came from here - I'm guessing that I looked at the wrong thing - what should I have been looking at (re-enforces my concern about putting this stuff together for my self ). My figures for DD packages came from here

I do get the feeling that you are expecting to buy a package that you can just plug in. No way, Hosee. This a major exercise that will take some time and will require both mechanical and electrical skills and associated equipment. You are, from my knowledge of the subject, making this choice factor far too complex; the control of a small induction motor for a wood turning lathe is a very simple task for any of these controllers which are all designed for much more demanding operations. Whether you go with this one or that one, the amount of work you are going to have to do to install it is going to be much the same so you might as well go with the cheapest.

Food for thought - thanks for the warning shot across my confidence; better now than when I've bought the wrong kit and stuffed it up. I'm dismayed that even when purchasing from SG you found that it was not easy given that they pitch themselves as offering a dedicated Graduate package. Makes me even more suspicious of the claim from LRE that their kit can be fitted in 3 hours by anyone - or maybe that's why their kit is considerably more expensive - maybe it is considerably more comprehensive / well thought out?.

Thanks for responding and any other thoughts / experiences are more than welcome!

Miles