Hobbymat Mill - Motor and capacitor advice

Hello,

I've just got a HM BFE 65 mill, the motor has been taken apart (and reasembled badly) I have not taken it apart yet or tested, but the previous owner tells me that the motor and possibly the start cap are faulty.

Does anyone have advice on where I could get a compatible and fit motor or a service that would look at it? Any info on a replceement start capacitor would be useful also.

Many thanks Chris

Hi Chris, this is the only help I can give you.

Regards Nick

Suppression of interference with condenser forsooth! Written by a knowledgeable person clearly. Capacitors easily and cheaply available from sources such as CPC Farnell. The motor is probably a standard frame size so a replacement should be easy to source. There are motor rewind companies around that could fix winding problems. If you did decide to replace the motor you could consider a 3 phase type with a small vfd which would be smoother and give you variable speed.

The motor and capacitor can easily be tested. Where are you ? Noel

With luck someone on the forum has replaced their motor and knows what to buy! Otherwise Chris will have to dig around to find an alternative.

The Capacitor should be easy because they often have to be replaced on this type of motor. Search for Start/Run Capacitors on the web, they're sold by Farnell, RS, CPC and many others. The spec is in the circuit diagram 8uF, 460Vac. Don't rush to buy one unless the motor can be reassembled, because new motors come with new capacitors. There are firms who rewind and mend electric motors, but the cost is likely to hurt. It's economic to repair big expensive motors, but usually cheaper to replace small ones.

Finding a replacement motor will be more difficult because the type isn't listed. However, it's single-phase, 220/240v, about 435W (say 1/3HP). Any motor that physically fits the mill between about 1/3 and 1/2HP will do. Might be a standard footprint, possibly not.

EBM 63 K2 is the maker's part number. There's almost certainly a modern equivalent. I'd start by measuring the layout of the fixing holes etc on the mill. Then look in catalogues for motors that match the fixing; the motor might not electrically correct, but the catalogue may name the fixing standard, which will make searching much easier. EBM are now EBM-Pabst, this is their current catalogue.

The sins of previous owners can be a problem when buying second-hand. We pay for the things they did and shouldn't have, and things they should have done and didn't! In this case, the most likely cause of failure was the cheap and easily replaced capacitor, and taking the motor apart was a mistake. But once a motor that fits is found, they're not difficult to install and get the mill working again.

Dave

Dave

I believe the motor Frame size is 63 with 250W power output and 2 pole for 2850rpm, as per the list posted by Nick.

Emgee

Pictures of the BFE65 show a flange mounted motor, so a 63 frame with a B14 flange, 2 pole 250W. Ebay has such an item for around £105 delivered here

One point to note is that the original motor had a small connecting box with a remote mounted cap - the modern motors seem to have a large connecting box that contains the cap. Space is rather at a premium at the top of the machine, so a large connecting box may not fit in the space available.

I suspect that while the original motor has "EBM" in the model number, it is very unlikely to be an EBM make motor. A quick Google brought up the rating plate of an original MD65 lathe motor - also 250W but foot mounted rather than flange. This showed it to be a product of the VEB Elektromotorenwerk Gruenhain with a model number of EBMW 63G2-SE11. I suspect that it is far more likely that the GDR manufacturer of the machines used a GDR motor supplier rather than a FRG maker.

Nigel B.

edited to add link

Edited By mgnbuk on 24/08/2022 13:05:55

What Nigel B says (2 pole,250w, 63-size frame) but is a B14 face mount rather than a flange - the spigot / ring is 60mm and the bolt PCD is 75mm.

A problem that you might find is that the OEM motor has a 14mm shaft and the cheaper modern ones commonly tend to be 11mm; though shouldn't be hard to sleeve or make a new drive collar if you have to.

Shaft length is 30mm and the keyway slot 5mm.

Just noticed that the link I gave earlier doens't actually have the correct motor - though the "drop down" menu allows selection of the required power, mounting & speed, the details further down show that the 0.25Kw motor they sell is 71 frame, not 63.

This supplier does list a 63 frame 0.25Kw 2 pole motor, with the face mount option available.

While Googling VEB Elektromotorenwerk Gruenhain I was pleasantly suprised to see that the company survived reunification and is still trading.

Nigel B.

Hi Noel, I am near Newport Pagnell J14 M.

Thanks everyone for your replies, very helpful and appreciated.

I got this for £130, and pleased that mechanically it is very good, gears, feed, table etc all working well and in good nick. I did one of these a while back which was seized everywhere it could be, but the motor was good so have striped one down before.

I am not great with electrics but apart from the cutting of wires, easy to resolve, the base of the motor fins do not line up, so I am pretty sure it has been opened. There is also a big dent in the blower cover, but that could have been from anything and does not interfere. Spinning by hand I can feel an area of quite hard resistance but before it frees off again.

I will look to take it apart in case of anything obvious, I don't hold out too much hope given my lack of motor knowledge.

Given the above comments on a potential replacement motor, I had a look on these guys website, when I did my Pollard to 3ph & VFD they were very helpful - I should update that Pollard drill post and will..

I've not physically measured up yet until I discount the OE motor, but ballpark spec this seems to be there abouts. Length of drive spindle looks like an issue. Any views on that other than physical dims? I don't really want/need to go 3ph VFD with this.

https://inverterdrive.com/group/Single-Phase-Motors/TEC-Single-Ph-Motor-550W-2800RPM-LST-63F-B3/

I will post some pics once I've worked it out again, and also once I have the motor apart.

Thanks again all for your help and advice.

Pics !

Hi Chris, I definitely think your motor has been reassembled incorrectly, which may account for it having a bit of resistance in one place, where things are not correctly inline.

Regards Nick.

Hi Nick, well I'll be blown...

Unbolted the motor halfs retaining screws, which were mostly missing their nuts, realigned the motor halves properly, and spinning nicely by hand.

Took the NVR switch out of the mill head and temporarily wired it all up (forgive the bodge bench rig)

Well it runs on the button very smoothly. I have no idea what the previous guys had been doing, perhaps it blew the plug fuse

So a working BFE 65 for £130 - no complaints

Hi Chris, good to hear you have a successful result.

Regards Nick.