# Difference between Weiss and Precision Matthews



## AndySomogyi (Jul 6, 2020)

Looking at purchasing a Weiss WBL290F or a PM-1127VF-LB?

They both look identical, same 11.5x28” 

I can get a Weiss delivered from toolots.com for about a 3/4 the price of a PM.

Not super concerned about accessories, mostly interested if there’s any difference in bearings or other details.

Spec wise, it looks like the difference seems to be a BLDC vs AC/VFD motor.


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## matthewsx (Jul 6, 2020)

I would give both companies a call and ask that question. Even if identical there may be a reason to choose one over the other.

John


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## hman (Jul 7, 2020)

+1 on phoning both of the companies with your questions.  If nothing else, you'll probably get a feel for what kind of support/response you can anticipate in the future.

PS - I might be wrong or crazy, but isn't "BLDC" just another name for a 3 phase motor????  Far as I know, BLDC refers to the motor, and VFD refers to the drive electronics.  So they're probably identical in all respects.

Another PS - I looked up both the lathes.  Only significant difference I could find - the Weiss comes with a 4-way tool post, the PM with a QCTP.  

Other than that, the specifications appear pretty much alike (given a few rounding errors and that the specs of the Weiss sound like unedited Chinglish).  About the biggest "difference" seems to be the motor horsepower - the Weiss claims 2HP, but then they say it draws 15 amps at 120V.  Does not compute.  The PM claims 1HP, 20 amp input, which sounds like the same motor, just better documented.


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## AndySomogyi (Jul 7, 2020)

A BLDC or brushless DC motor has permanent magnets in the rotor, and uses an invert to energize different sets of windings in the stator. A induction AC motor has a stacked plates in the rotor, and uses a rotating electric field to induce a current a current in the rotor, which creates a torque. I'm not really sure of the subtleties of the difference in torque characteristics (both are constant torque at lower RPM, and fall off at higher speeds) but BLDC motors tend to be more efficient. 

2 hp is about 1500 watts, so at 120V, would be 12.5 A. 

Both of these, the 3-phase induction and the BLDC are more efficient than single phase AC. 

But I'm not super concerned about the HP, on my last 12" Clausing, I found a 1 HP was pushing the limits of rigidity. 



hman said:


> +1 on phoning both of the companies with your questions.  If nothing else, you'll probably get a feel for what kind of support/response you can anticipate in the future.
> 
> PS - I might be wrong or crazy, but isn't "BLDC" just another name for a 3 phase motor????  Far as I know, BLDC refers to the motor, and VFD refers to the drive electronics.  So they're probably identical in all respects.
> 
> ...


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## Aukai (Jul 7, 2020)

Need to find out if it's a metric conversion, if that would be an issue. PM is true imperial, don't know on the Weiss.


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## AndySomogyi (Jul 7, 2020)

Aukai said:


> Need to find out if it's a metric conversion, if that would be an issue. PM is true imperial, don't know on the Weiss.



Unfortunately they’re both imperial screws. I wish I could find one that’s all true metric.


Sent from my iPhone using Tapatalk Pro


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## Aaron_W (Jul 7, 2020)

Looks to me like you get more tooling with the PM, 3 and 4 jaw chucks, QCTP with 5 tool holders, steady and follow rest, face plate and 2 dead centers (one for head, one for tailstock). All you get with the Weiss is a 3 jaw chuck and a 4 way tool post. Seems like that tooling would account for a significant amount of the $600 difference.

DRO Pros also sells the Weiss lathes, they have the WBL290F for $3099. Same machine and equipment as buying from toollots, but DROPros provides a 5 year warranty, not the 1 year warranty from Yuutools. There is also this from the top of the DROPros page:   "We speak English - We answer our phones".   

PM includes a 3 year warranty and there are a number of posters here who have gotten good support from PM. 


I think it is a safe assumption that part of the added cost is related to customer support. PM has mentioned that they are stocking parts in the US to support the machines they sell.


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## Aaron_W (Jul 7, 2020)

AndySomogyi said:


> Unfortunately they’re both imperial screws. I wish I could find one that’s all true metric.
> 
> 
> Sent from my iPhone using Tapatalk Pro



I'm sure they make them with metric lead screws for the non-US market. If that is your preference you might be able to special order one from one of the US distributors (PM, DROPros, tool lots), the one that says yes would be a good indicator of the kind of future service you might receive.


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## hman (Jul 7, 2020)

AndySomogyi said:


> A BLDC or brushless DC motor has permanent magnets in the rotor, and uses an invert to energize different sets of windings in the stator. A induction AC motor has a stacked plates in the rotor, and uses a rotating electric field to induce a current a current in the rotor, which creates a torque. I'm not really sure of the subtleties of the difference in torque characteristics (both are constant torque at lower RPM, and fall off at higher speeds) but BLDC motors tend to be more efficient.
> 
> 2 hp is about 1500 watts, so at 120V, would be 12.5 A.
> 
> ...


Wow!  My ignorance is showing   I'd seen some BLDC motors run by 3 phase power, but forgot to notice that they were PM, not inductive.  Many thanks for the clarification.  Maybe _someday_ I'll understand motors ...


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