Harrison Lathe M250 motor mount, is it pivoted?

[Ian PParticipant @ianp]

[Ian PParticipant @ianp]

I have just taken delivery of an M250 and in the last couple of hours have powered it up and started to feel my way round it. It is running off a static converter and my first job will be to replace it with a VFD.

I have the original manual but its rather vague (useless actually) at describing how the motor is actually mounted. If I pinch the V belt runs together the motor moves but I cannot tell if that's because its bolts are loose or whether its on a pivoted plate hence asking the question here.

Normally I would delve in and examine the machine myself but the lathe (heavy!) is back up against a brick wall although obviously I will have to gain access eventually to convert the motor wiring.

Ian P

[Nick_GParticipant @nick_g]

.

I cannot help you with your question.

But I would like to congratulate you on the delivery of a very, very nice lathe.

Nick

[Chris HembryParticipant @chrishembry84309]

Hi Ian,

Pivoted horizontally in the middle, with a jacking bolt on top right corner. Motor foot may also be fitted on slots on the mounting plate, but not checked that.

Chris

[Chris HembryParticipant @chrishembry84309]

Just a thought : since motor is moving, check jacking bolt is actually tight (M8)

[Carl Wilson 4Participant @carlwilson4]

Congratulations on your purchase of a first class machine. I would recommend joining the Yahoo Harrison Lathe users group. It has a wealth of information on the M250 and a very helpful group of members who will help you with any queries you may have. It has been a great help to me.

Carl.

[Ian PParticipant @ianp]

Carl/Chris

Thanks for both suggestions. In the manual there is a diagram that shows what could be a pivoted plate but whilst all the components on the diagram are numbered there is no table that identifies what each part is, something that looks like a washer might be a bearing but having no description makes it pretty useless.

I don't know why I did not think about the Yahoo group so thanks for reminding me.

Ian P

[Carl Wilson 4Participant @carlwilson4]

Hi Ian,

Having just consulted my manual I have page 26 which is the motor mounting breakdown. My M250 is a factory single phase version, but the motor mount is the same. There is a pivot and an M8 jacking screw as Chris mentions above.

Winding the screw in pushes the motor out against the belt tension and vice versa. Page 26a shows the component key, but as you say doesn't give much useful information, I have good access to the rear of my M250 so I will try to take some good photographs later today and post them here. It is about a year since I checked the tensiopn so it is about time. I cleaned the whole machine yesterday anyway.

Carl.

[Carl Wilson 4Participant @carlwilson4]

Here are the photos as promised. The first picture shows an overview of the adjustment arrangement. The pivot and upper and lower adjustment screws can be seen.

The second photo gives a close up of the pivot. The securing rawl pin and M6 bolt can be seen, as well as the keeper washer and it's M5 securing bolt.

The next two pictures show the upper and lower adjustment screws and lock nuts, respectively. By tightening/loosening these two against each other, the motor mount is pivoted and hence the belt is tensioned or slackened off.

[Ian PParticipant @ianp]

Thanks for those Carl, it makes much more sense now. I think that on my machine both screws are backed off and the weight of the motor is providing the belt tension. As it happens the belt is covered in oil and the rubber is all soft and swollen so a new one is in order.

Somehow I will have to move my machine away from the wall so that I can access the motor to change it to suit the VFD. I'm hoping the presence of oil is because of enthusiastic over oiling of the change wheels.

Ian P

[Carl Wilson 4Participant @carlwilson4]

Hi Ian,

I have moved mine a few times and here is how I went about it. You will need an engine crane and possibly a pallet truck/pallet, you can hire the first two. Most haulage places or even supermarkets have so many pallets lying around that they'll let you have one. This is a two man operation.

There is a lifting point on the bed, just below the chuck, You may find this has a protective grub screw threaded in. From memory it is M10. Take the chuck off the machine and thread an eyebolt into this hole. Then choke a strop through this, or a loop of polyprop rope. adjust your engine crane to reach this and bring it in from the headstock end, hook it up. Move your tailstock as far up to the headstock as you can get it, this will help with the balance of the machine as you lift.

Pump away on your engine crane. Your machine will come up headstock end first, After only a couple of inches on the headstock, the tailstock will come up. Once you have the machine in the air, two of you will be able to shimmy it into the new position, then slowly lower, carefully. Ensure that as you lower the machine it does not catch on the legs of the engine crane. If it does, disaster will ensue.

If you need to move it further, you'll need to get yourself a pallet. Chop your pallet up until it is an exact fit to the base of the machine. You may need to reinforce it a bit with some of the discarded timber. Lift as above, then put the pallet in under the machine. Lower the machine onto the pallet. Clear the engine crane and then you can get your pallet truck in. It is highly advisable to secure the machine to the pallet with a cargo strap before you move it. Take it steady, and have your helper push the machine whilst you steer it.

Carl.

[Ian PParticipant @ianp]

Carl

Thanks you for your very comprehensive instructions for moving a lathe. I fully understand that yours is the right way to do it but I want access to the rear for a short time and at the moment dont want to borrow or hire special lifting kit.

The lathe is on some 1" thick wooden pads and what I will do with long bar is lift each end in turn until I can slide in (front to back) lengths of steel bar or tube that the lathe cabinet feet can be slid on. I already have a 6" gap at the back so another foot or so will give me enough room to get to the motor.

Ian P

[Carl Wilson 4Participant @carlwilson4]

Hi Ian,

Ah, ok no worries. Hope you get everything sorted so you can start enjoying using your new machine!

Carl.

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