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View Full Version : Help needed, advice on dismantelking baring holder/ballscrew



george uk
09-04-2014, 02:58 PM
Hi

I have to part dismantle and SCM Tech95 to move it and get it in my workshop

I am removing the top canitleaver section ( the full moving bit.

I think i need to remove the screw as the baring housing is fixed through the cantileaver ( Y mech )

her is a picture, can anyone suggest dismantling instructions, i think i know but its always better to ask advice from experienced people. Although any advice is welcome

12022

george uk
09-04-2014, 03:38 PM
this is the conection to the Y

12023
i think i will tyake the full bscrew off at both ends so i dont have to remove that bearing from the Y

its big

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george uk
13-04-2014, 02:00 PM
Hi

Can anyone suggest a good way to remove a pully belt under tention. Its the one pictured above, ie is the a better way than brut force, any suggestions welcome.
1205012051

Clive S
13-04-2014, 02:04 PM
What's stopping you just unbolting the motor? ..Clive

george uk
13-04-2014, 02:09 PM
Accesses is hard to the rear, but i will give it a go.

Is that the usual way,

and am removing the pully to get behined it, so i can remove the X screw, with the baring intact. I have to remove the full Y Mech to get it in,

EddyCurrent
13-04-2014, 02:13 PM
There must be a way to release tension from the belt first ?

george uk
13-04-2014, 02:24 PM
I am suspecting clive pointed out what i need to do.

I was just overthinking it, its qurquard so was looking for the lazy way. i was hoping it would have enough give so i could streach it over,

Ger21
13-04-2014, 03:16 PM
That's looks virtually identical to our Morbidelli. I didn't realize that they are apparently the same company, or one is the parent company of the other.

I would think that you can push the head towards one end, then unbolt the screw and just turn the screw through the nut. Then you don't need to remove the pulley. Be careful, though, as there's a good chance that all the balls will fall out of the nut when you pull the screw.

JAZZCNC
13-04-2014, 03:36 PM
Those four bolt heads holding motor look like could be eccentric cams to me.? Those will be whats used for tensioning the belt if there are no other signs of tensioning.

george uk
13-04-2014, 03:54 PM
Ger --- thzats my final option, am tryin g to avoid winding it off.

Jazz ---- Yes, i think if i can get them loose, that will give me the room i need. I just dont have the exact tool i need, typical,

Question. if am unable to loosen the motor, will it be problematic winding it off and just putting the balls back in . Ie is it worth me putting more effort into removing them bolts, or is it ok to wind the baring of the screw ?-- not just the pully but the baring set listed above ?

--------update-------

unwound the screw of the baring,--- needs a good clean out anyhow....

Ger21
13-04-2014, 04:34 PM
If you remove the retaining nut (part #16), you might be able to slide the ballnut right out of the housing, and leave it on the screw.

george uk
13-04-2014, 08:06 PM
had to unwind it in the end, i just didn't have the tools to hand that could access it properly, need a forklift and driver tomorrow now

magicniner
13-04-2014, 08:10 PM
Be careful, though, as there's a good chance that all the balls will fall out of the nut when you pull the screw.

Turn a length of plastic rod to the base diameter of the screw (bore to accomodate any reduced end on the screw) and run that into the nut as the end of the screw moves through, the balls will be retained by the plastic which you leave in place until re-installing the screw.

EddyCurrent
13-04-2014, 09:01 PM
This is the best video I think showing how to repack a ball nut, it worked for me no problem. It also shows the idea magicniner mentions to keep the balls in.

Linearmotionbearings C7 Ballnut Flipping and Repacking - YouTube (http://www.youtube.com/watch?v=5qbVrRYzK5U)

george uk
14-04-2014, 04:24 PM
am presuming these are vac locked, does anyone know if there is an easy way to release them without powering the machine

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Ger21
14-04-2014, 05:06 PM
I've used a machine in the past (Masterwood) where they were locked with compressed air. But they were free with no air, so I'm not sure. Are they possibly seized?

george uk
14-04-2014, 05:15 PM
I suspect its a reverse vacuum, and am looking for the release points. will give it a go by opening one point on one. There are release buttons, but they done seem to do anything when the powers off

george uk
23-04-2014, 02:53 PM
Well, we eventually got it in the workshop. Now onto the servicing.

Any pointer on best way to service rails and blocks. They have grease nipples but are hammered with fine particles, I would rather not fully disassemble if possible. Am thinking

1. warm the block, ram loads more grease through, till it runs clear, wipe residue, repeat every 2 weeks untill no trace of particles.

anyone advise or opinion on this

2. basic soapy water for the rail and machine, clean up with pure alcohol .

Also, i wander if anyone could talk me through some electronics questions in relation to the supply to this.

The machine ( scm tech 95l ..1998 ) says 400w 3p on the cabinet. Plugged into that, separate, its what looks like a huge but basic inverter ( am guessing 240v 3p to 380v 3p ).

If i wish to run this off a large genny, what extra power should i consider ( above the machine draw )

It look like it would run from both 240v 3p and 380v 3p, but the box says 400v 3p. the possible genny outputs are 240v 3p 380v 3p and 415v 3p. I understand that if i run it at 240v 3p, it will be lower powered, but maybe thats not a problem for me, What i really dont understand is

1. Is ther any benefit/loss using the inverter to go from 240-380
2. if the genny outputs 415v, would i have to invert that down to 380v
3. any advice or opinions on using a genny with a large machine.

mm, thinking, i may need to check the inverter, as it may be 415-380, but i doubt it, it looks like 220v to 380v inverter. ( the inverter looks like its SMC branded and purchased with the original machine

EddyCurrent
23-04-2014, 06:02 PM
Gunk might be useful for the cleanup too ?

With regard to the voltage, you need to find out what voltage each component is rated at. The spindle motor and VFD will be the first to look at, the other components will normally have a lower voltage rating but will be supplied via a transformer or power supply so you need to see what the input voltage is for those items. From the sound of "400w 3p" this indicates a control panel taking 400 watts at 3phase voltage (did you confuse this later in your post with "400v 3p" ?) If it is 400 watts then it sounds like a 3phase 415v (or thereabouts) transformer is supplying the cabinet and this could be replaced.
The inverter will have to match the spindle motor or if you want it to work on single phase you might have to replace the inverter and motor. There are other threads in this forum about running spindles and inverters from various voltage sources.

george uk
23-04-2014, 06:38 PM
Hi eddy. I will get some Gunk ( i presume thats the proper name )

on the electric side.

The main brain box ( electrics cabinet with the pc, vdf, servo drivers and controllers, has its own sets of inverters built in to get 5v 12v 240v and drive servoes and encoders and VDF ). Seporate to that box, is what looks like huge transformer or inverter. ( not statndard to the machine ). I may as well buy a genny to run the 3phaze than convert it. Its a hugh and heavy machine ( 4mt long, without the brain cabinet ). i doubt it would run on single phaze without a massive gearing system.

I suspect, that the place were i purchased the machine of, may have had 220v 3p as a supply and used the inverter to upp it to 380v 3p ( the machine standard ), but am not sure, i will take a picture tomorrow and post it up. I need to know so i can get the correct or best matched genny

GEOFFREY
23-04-2014, 09:58 PM
Hi, I think that you will need a proper 3 ph supply to run your machine, on my SCM the spindle is 7.5HP and the vac pump needs 5.5KW. G.

george uk
23-04-2014, 10:33 PM
My spindle quotes ( i think ) 5kw at 380v and 3.6kw 220v on the case, the motors on the saw and multi drill head both quote power at ranges from 220v to 400v on there cases. the servoes are .75kw.


Hi, I think that you will need a proper 3 ph supply to run your machine.

do you think a genny will have problems running it. i wasnt sure, i was thinking a big genny, something like this maybe.

16 KVA Diesel Generator 3 Phase Lister ST3 Engine Stamford Alternator | eBay (http://www.ebay.co.uk/itm/271453972140?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649)

but if i can offload the vac and compresser, i wander if i can used cheeper jenny ( used obviously )

GEOFFREY
24-04-2014, 12:05 AM
I am sure that if you use a genny that size you will have no problems running your machine, but I think that fuel costs and noise may be the downside. From the pictures you posted it looked like the machine is likely to be used in a residential area, and that is why I mentioned noise. Without a vac pump you may be able to get away with about a 10KVA unit. I don't know exactly what you are going to use the machine for, but I would not like to be without the vac hold-down system. Have you investigated the cost of installing a 3PH supply? I know that can be expensive, but it may prove to be the best answer long term. Anyway, good luck with whatever you do. G.

JAZZCNC
24-04-2014, 12:56 AM
do you think a genny will have problems running it. i wasnt sure, i was thinking a big genny, something like this maybe.

You'll not run this from a Genny. Gennys don't supply a stabel enough power and the Servo's will go bonkers.!

Also I'm no electrics expert but your thinking about Inverters changing voltage is wrong, they can only put out what goes in. So 240 in 240 out, they change phase/frequency not voltage.

Rotary converters will change voltage but they are quite inefficient and you'd need a bloody big bugger for this.!

george uk
24-04-2014, 01:44 AM
You'll not run this from a Genny. Gennys don't supply a stabel enough power and the Servo's will go bonkers.!

thats the info i need, is it get roundtable, could i stabilise the genny output. could you explain a bit more her please jazz so i can understand the problems.


Also I'm no electrics expert but your thinking about Inverters changing voltage is wrong, they can only put out what goes in. So 240 in 240 out, they change phase/frequency not voltage.

I will take pictures tomorrow so you can see what i mean, the extra box seem to have three large transformers ( windings ) or capacitors, and nothing else ( mabe four actually, will check tomorrow )

do have some money to spend on this but think the cost of supply 3 phase is prohibitive, i would rathewr have flexible options if available


Rotary converters will change voltage but they are quite inefficient and you'd need a bloody big bugger for this.!.

Maybe this is the wayi just want to have a look at all options.

I do have a full independent 1 phaze supply to my workshop ( flat at back of garden, ). the machine main box says 400v 3f 35a. But i dont need the full capacity that its rated for. I purchased this, not to use fully as is, but to convert into the type of machine i need. 2 high power motors on the other heads are not needed. I may not even need the hydrolics systems that drops motors/spindle/heads. as the Z is on full rails.

On the 3 phaze side, i may only need to drive 3 * 0.7kw ( i think ) servoes and drivers ( or maybe 4 ), the VDF and spindle, --- so push come to shove, thats what i need to power... plus if i can get exsess, i will use it...


From the pictures you posted it looked like the machine is likely to be used in a residential area, and that is why I mentioned noise
ha ha yes, i have had this house her more or less 18 years, my neigbours are great. Getting it dismantled to get it in was a bit of a communal neighbourly job, and my workshop, is right at the bottom of the garden, its was a proper flat, just small, so its double walls and sound proff to some extent. I have blown things up down there a few times ( literally ), its got its own enclosed garden with high brick walls.

GEOFFREY
24-04-2014, 09:12 AM
It is possible to get generators that will give a stabilized pure sine wave output, but I do not know if that would be economic with such a large power output. I think that even running a rotary inverter is likely to be too much for your normal domestic supply (I once ran a 3PH 4HP saw on my normal domestic single phase supply, saw worked fine, but whole house lights flickered on saw start up and I figured that the rest of my street that were on the same phase probably had the same problem!!!). Are you sure your Z axis is hydraulic? My machine has an air ram to counter balance the spindle and the auxiliary drilling heads have pneumatic plunge. The main Z axis has profiled rails and a ballscrew.Whilst I generally think "if it aint broke, don't fix it", as your usage seems to be very specialist I wonder if you would indeed be better off taking advantage of the super strong build quality of your machine mechanically and completely reconfigure the electronics to suit single phase, although that may mean downgrading the spindle power. I am glad to hear that you have good neighbours, moving that machine to the flat at the bottom of your site must have been quite difficult. G.

george uk
24-04-2014, 10:27 AM
hi


Are you sure your Z axis is hydraulic? My machine has an air ram to counter balance the spindle and the auxiliary drilling heads have pneumatic plunge.

yes, mins the same i think.


you would indeed be better off taking advantage of the super strong build qualityof your machine mechanically and completely configure the electronics to suit single phase.

i need to cost that option.


I am glad to hear that you have good neighbours, moving that machine to the flat at the bottom of your site must have been quite difficult. G.

Will post photos when finnished. we had to achive a minumum cross section of 148 cm to get the part down the ally. and the ally floor is badley uneven.... it made it by less then 20mm, and we had to get it 40mters down the ally, then we cut a 5 mtr Ibeem into the side of the workshop, and slotted the machine in the 4500cm hole.

2 jacks, 2 pullys, 6 friends, 2-3 neighbours, lots of wood, and volumes of tea, Yorkshire tea made with lincolnshire water. PURE MANS FUEL.

EddyCurrent
24-04-2014, 11:10 AM
I wonder if you would indeed be better off taking advantage of the super strong build qualityof your machine mechanically and completely configure the electronics to suit single phase, although that may mean downgrading the spindle power.

That's the angle I was coming from in my earlier post.
Photos are going to be a must on this one I think.

george uk
28-04-2014, 11:30 PM
right, took a few days to get everything in position so i can get to work on it. I need to transfer the picture i have sofar of the electronics to post them, am picking up the extra box tomorrow. so will post picture of that. I have a number of options with power and would like to explore everyones thoughts on the options am looking at, i need to work out

1. what's possible
2. what problems each may have
3. costs

in relation to power.

as as stated above, machine is 3 phase, 3* 0.85kw yaskawa sgdb 10vd and 15vd servos plus drivers. that i definitely want to use, a 5kw or 3.4kw spindle and driver ( frenic 5000g9s ), that if possible would like to use. It also, has 2 motors to run a saw and multi ( 15 bit ) drill head mech. and an air ram attached to each to lower out of the hood. that if i can use i will, to some extent. It has a compressor ( will put KW up tomorrow ).

I have fully independant standard supply to the workshop ( 240v ac )

I am re-designing the machine to be multi use, so i can explore a number of options for electrical supply. and this is need a bit more info on the advice above, i will try post the pictures from my phone, and i still need to take a picky of one part ( additional box )., so

generator options, is it doable from a 3 phase genny, what power ( KW ) ?

conversion to single phase. would it mean totally replacing everything,

rotary converter, does this make more sense than a genny.

any opinions

EddyCurrent
29-04-2014, 10:43 AM
I worked in an electrical department during the time of the "Y2K Millennium Bug", the company had hundreds of PLC's, variable speed drives AC and DC, PC SCADA systems. Large generators were hired in the event mains power went down, tests carried out indicated the equipment would operate okay from the generators however it was an interim plan and not designed as a long term solution.
If you were to calculate costs over time for fuel, servicing, etc. and if you wanted to take advantage of the machine in it's current state, I would think installing a 3 phase supply would be the best solution or it may be possible to hire a small workshop on an industrial estate that already has it installed.
The other option as Geoffrey mentioned would be to convert the machine to single phase but I'm certain you would struggle to provide enough kW to bring it up to it's present specification.

GEOFFREY
30-04-2014, 12:55 AM
I'm sure that you will not get the machine to run on single phase as it is at present. It would mean sacrificing some some elements (reduced spindle power, smaller or no vac pump etc.), but I suspect that the cost and other problems of installing 3phase or using a large generator is likely to rule out keeping the machine as 3phase. I am fairly sure that from what has been said a small unit with 3ph already installed will also be a non-starter, and anyway I know that you , your friends and neighbours will not relish the idea of moving that beast again. These machines are likely to have have a power requirement of at 10-12KVA and I think you will find that is "pushing" your luck if you try to run it on single phase in its current configuration. G.

george uk
30-04-2014, 01:23 AM
Hi,plastng to plan tomorrow, had a noseop and it runs at both 220&380v . Have seen some large rotory converters for 1500, but I need to look more into gennys, Getting it from the elecy company is problematic to get it to the workshop and would cost around 3k. Wereas, if a genny or rc can work, I have plenty of space.

I realy need to do the numbers for the electronics tomorrow to get a starting point

m_c
30-04-2014, 01:38 AM
It will be possible to run from a generator, however it will need to be sized appropriately.
Best option will be to phone a couple different generator suppliers, explain to them what you're powering, and see what they suggest.

My guess would be aim for a generator with at least twice the KVA rating of what you need in total. The big issue will be voltage dipping/surging while motors spin up/down. The main spindle shouldn't be too bad, as the VFD will ramp up to speed off load, so there's no major start-up surge. However the vacuum motors will most likely be a simple contactor control, which will most likely cause a pretty large start-up surge.

And by the time you pay for a suitable genny, that 3k to get proper 3phase will most likely appear reasonable!

george uk
01-06-2014, 12:37 PM
Just before i start neew thread, in relation to the ballscrew...

We seem to be missing a few balls, after stripping and servicing the main ballscrew, any idea of a good place to order them from if i can get the correct size... ( if anyone else servicing one of these scm morbidelli, it does not dismantle the way the service manual says, its more complete than it looks ).... any suggestions.

secondly, controller options. any suggestions for a controller that could deal with servos and steppers, industrial types. an mot stuck on this, but am thinking i want 4 more motors for positioning, 2 only need to be very light ( scan, cam, touch probe, plastic extruder, ), i also wish to add an alternate Y mech for a laser, but am thinking it will cost a lot less in steppers than servoes, if both are drivable at the same time.

any suggestions.

Lee Roberts
02-06-2014, 08:27 AM
We seem to be missing a few balls, after stripping and servicing the main ballscrew, any idea of a good place to order them from if i can get the correct size... ( if anyone else servicing one of these scm morbidelli, it does not dismantle the way the service manual says, its more complete than it looks ).... any suggestions.

Try Gary @ Zapp he may have some he can offer you.

.Me

george uk
02-06-2014, 12:02 PM
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Here is the baring after a clean, about 10 balls misplaced, here is 2 of the pictures showing what we had to do to move it. we managed to get the cross section of that green bit down to 150cm to get it down the ally, still not sure how we made it. Good job that i have great neigbours, and no onew minded us closing the road off twice. ;->

Clive S
02-06-2014, 12:28 PM
12506125071250812509
Here is the baring after a clean, about 10 balls misplaced, here is 2 of the pictures showing what we had to do to move it. we managed to get the cross section of that green bit down to 150cm to get it down the ally, still not sure how we made it. Good job that i have great neigbours, and no onew minded us closing the road off twice. ;->Well we have seen people put cnc's in there spare bedrooms study etc. But into your lounge:whistle:!! and not through the door that's what I call keen:star: Good luck. ..Clive

george uk
02-06-2014, 01:30 PM
Well we have seen people put cnc's in there spare bedrooms study etc. But into your lounge:whistle:!! and not through the door that's what I call keen:star: Good luck. ..Clive

He he he, well, at least the council will stop asking why i seem to have a livingroom,bathroom,kitchen and bedroom in the workshop... ( somewere to chuck the kids when they were teens and stroppy )... We are just planning how to get a mill am bidding on in, i underestimated the width of this by 50mm and it caused loads of work..

GEOFFREY
02-06-2014, 11:41 PM
Unbelievable, Well done. G.