Electric Motors/brushes

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Question
I have a Lealand 1/3 hp motor I think from the 1920's or 30's
type ra
form arwjh---some of the info is hard to decipher
the springs on the brushes have collapsed and the connector copper wire is burned off---I can find no supplier for the brushes
thank you for any suggestions you might have

Answer
Wayne,

A perfect compressor motor, but we can dial another in if this becomes a problem for whatever reason,    but I would hold onto it working or not,     just too neat of a technology from back then, and not many around,    not that it will ever be worth a fortune but it might be get to a point it has some serious value,    they do make new repulsion induction motors to spec for specific applications,  and they are HIGH DOLLAR         

If you can get your guy to clean up the segments and get some new springs and brushes in there,  if nothing else is hanging or a problem     it probably just ran out of brushe and that in turn caused the arcing,   common for that to happen  and not at all  a definite total failure     the brushes wont be cheap   unless they have a set that is close where they only have to do a bit of modifying   but to spend $75 bucks on that motor    I would,      you can write me anytime if the costs start mounting and we can go over what other options we might try   hell maybe someone has one that has no use or concern for it, and has a good set of brushes in it,   maybe pick it up for little of nothing,    never know,     



 those brushes short out the rotating element,  allowing it to act like a DC with high torque in low RPM  and then mechanically release  and the motor becomes more like a traditional induction motor,        

The motor is valuable, simply because they are very complex, and the fact that so many were scrapped for the little copper that could be harvested a shame,          

It will be some sort of PRE NEMA FRAME<    meaning before the National Electrical Manufacturers Association came into existence and started to put conventions and standards to motors by size and frame, and HP        it was sort of catch as catch can,      

A couple things,   the brushes are probably wedge shaped,  and there is probably a mechanical spool,    make sure that device is not gummed up and operates freely       whatever the design  

Next the copper braided wire from the brushes,  are shunts,      

MOST LIKELY  without seeing it,   the brushes became so short the spring pressure was not strong enough to hold minimal tension against the commutating surface,  the round area with copper segments,          

It should be dressed in a lathe   it just depends on how many pits and how distorted it got with the obvious heat          

You will need all new springs,  and brush/shunts   along with dressing the contact surface.

If the contact surface is pitted or rough and the new brushes do not make flat complete and adequate contact pressure, the current will tend to arc or jump,  and this is ongoing,   it just gets worse and worse until the new set is now burnt from the arcing,     so it is something you will need to deal with,     

To get the correct set of brushes and springs,  you will need to send a sample to Helwig Brushes        


Here is their contact info,  phone numbers, catalogs, so on,    best bet,   call for a order number,   they might be able to price you over the phone   Leland Motors were very popular for repulsion induction motors,   and there is chance they have the exact brushes and springs in stock, but it will be a long shot,       more likely they will have to manufacturer you a complete new set and there are minimums involved,      so about the only thing you can do is hope the minimum is two sets   so you have  spare set,      

I can guess at the price,  but it would be just that a guess,   just too many variations,  and minimums change all the time,       not good news but the only news,      

I know over my decades of repair I have bought hundreds of thousands of dollars of brushes from Helwig,   there are not many other choice   Carbone is one,   I have used them  prefer Helwig and most likely the original brush was Helwig,         

So even if you find it in one of their catalogs,  I would spend the few bucks on sending the best samples you have left over,     along with anything you can read off the data plate,   maybe a photo of the unit,        

Get an RA number from them,   they will send you a matrix of pricing,  and from there you decide depending on the minimum    how many to order,   like I said   say the min is 1
$150.00  and one set is $70  then there is no decision,   get two sets,      

But they will be fair,  they will sell retail,  it is not going to be "cheap" but without the correct makeup of brush, the correct makeup of shunt  the correct spring pressure it is just a waste of money and time,       

You have one hell of a motor there,     probably one of the most collectible types of old vintage motors around,       and probably could be sold to many word workers who keep old wood working tools around or rebuild them,          

Used I would not chance,   if it fails  shorts internally a week down the road,     not good,  

If you have a local motor shop, they might have the right brushes depends on the type of shop  if they still deal with vintage gear or not,   but they can machine your rotating element and check your mechanical operation along with measure your insulation values,      might be worth the rebuild price to let them do the whole thing,     

Worse to worse,  you can mail it to me,  we do obsolete motors from all over the country and know repulsion induction motors as well as any other motor,         it is an option  but locally is probably better to avoid the shipping, and I know this is no light weight motor,   

IF you take the motor down any further than the brushes    take a photo of the motor,  of the connections  of everything,    matter of fact do that anyway,      tags fall off,  marks get rubbed off,  so if you are going to go any further make sure you have photos to refer to,      

Need anything else,  let me know,  

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Three phase/ AC DC single phase motors, controls, any problems or failures, motor installation, performance issues, connections. All other electric motors/gearboxes/apparatus. Specialty repair concerns, obsolete motors and solutions. Other mechanical or specialty equipment. See my profile under Home/electrical at this site

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30 plus years in the electrical motor and apparatus repair industry. VP level management of repair facilities, current owner of my own specialty repair and consulting firm.

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