Making an electric motor adapter for Nema 56C to a B5 D71 Flange

[calgaryguy]

Per the title, I need to make, or have made, a plate adapter to go from a NEMA 56C *inch fractional* frame electric motor housing flange to a B5 D71 *metric* flange. I dont think the Craftex lathe I have access to is a) has a chuck capable of spinning a flange this size, and the RF-30 mill I have access to is beat to shit and isnt very precise anymore, nor do I have a good/accurate way to index things like the bolt holes and spacings required

NEMA 56C drawing is attached for reference. Picture of a typical Leeson 56C attached as well.

The *KEY* dimensions from the attached 56C pdf drawing needed for the 56C motor facing side of the proposed adapter plate are the BF and AJ measurements for the mounting bolt hole size and spacings AND critically the AK dimension which would need to be a recess in the motor facing side of the adapter. proper positioning of AK, BF, and AJ will ensure that the shaft stays perfectly centered in the flange.

The thickness of the adapter plate is dependant on two key measurements:
1) The ACTUAL shaft length protruding from the motor housing. The attached PDF has that measurement as 2 1/16", but I have seen NEMA 56C motor (princess auto cheapos for eg) advertised with 1 7/8" to 2".
2) The shaft length that must protrude from the face of the B5 Flange side of the adapter needs to be 1.185". This length is critical as there is a gear that gets installed on the shaft that meshes into a gearbox.


The B5 flange side of the adapter needs to meet D71 metric specs. Please see the attached IEC B5 D Flange dimensions PDF. Note again I need a Frame 71 size. Also important to note that IEC Frame 56 and NEMA frame 56 are NOT the same.

I dont have CAD and my fusion360 skills are non-existent. I did HOWEVER find the a CAD/STEP file for a NEMA frame 56C to IEC B5 *D80* adapter flange at https://grabcad.com/library/56c-frame-to-b5-frame-motor-adaptor . Can this be easily modified to have a D71 face instead of a D80? I've downloaded the .stp file and zipped it and the available redering from grabcad and attached it here for anyone curious.

 

[eotrfish]

Yes - I'm curious.

There may be a problem. Here's a drawing of the adapter with B5 D71 dimensions. Note that the AK dimension (a recess in the motor facing side of the adapter) comes very close to the 10mm mounting holes. Also the major OD can not be reduced to 160mm from 200mm per B5 D71 but that should not be a problem.

 

[Proxule]

Post in thread 'New to me RF 45 ..... In the shop'

Dec 31, 2024

close enough flange dimensions, but there were some variations to the shaft length/diameter/key

This is why I made my own adapter to go from the 145TC ( 56c is an option too ) to that metric shit on the RF45.
I also bought a larger shaft motor ( 145 TC ) and opted for the 3600 rpm version, Turned the shaft down and milled a new key way ( diameter is metric and keyway is metric ). Attached it to my 3d printed adapter ( PETG ) and bobs your uncle!
None of that silly metric motor garbage.

• Proxule

• 

 

[calgaryguy]

The major outside dimension of the piece can stay 200 or even 180 I think, I'll have to check the gearbox housing for clearance.

The end application here is a 'made in italy' by 'SCM' https://www.scmgroup.com/en_CA/scmwood/products/edge-banders-squaring-edge-banders.c863 The EU manufacture explains the IEC motor use.

I obtained this machine for essentially scrap value. It is a 'Basic 1' model from the late 90's. Edgebanders of this type are worth a few thousand dollars and up depending on age and condition. I'd like to see if I can get it back into good nick and either use it for the odd jobs I do, or sell it. barring getting it running, I'll part it out and take the 800lb carcass to the recyclers.

Sadly the motor in this one was a) an oversized (a 1hp and not the original 3/4hp) single phase replacement for an original 3 phase unit, b) pretty much cooked field windings and an armature whose shaft ends look like they've been mashed by a 13 year old with a ball peen, and c) as mentioned a IEC metric frame motor. The motor control cabinet wiring has been altered to for the whole machine to run on 220v single phase. The motor Still sorta ran but would start to squeal loudly after 30-60 mins of use and was running excessively hot for a TEFC motor (outer housing measured at 100C or higher during operation), I put new bearings in it as the originals were cooked (FAG 6204 2RS) and it cooked those bearings in about 2 hours of non-loaded bench runtime. I can buy a cheapo 1/2 or 3/4hp TEFC C flange motor for 270 bucks (Princess auto) so its not really worth pursuing a motor rewind/repair IMO.

Here's some pics of the armature mounted in the B5 71 integral housing flange

Oddly the casting letters seems to imply its a D80 flange, but all dimensions clearly show its a D71 flange and it does not appear that its been machined down from a D80. Major diameter, bolt hole spacings and the integral locating ring are all D71 specs.

 

[Janger]

An edge bander… I had a vague idea of those machines. Now I know more..

 

[calgaryguy]

An edge bander… I had a vague idea of those machines. Now I know more..

They are a fairly complicated machine, almost rube goldberg in nature. Requires shop air to drive relay/service triggered air pistons for the trimmers and guillotines. The one I have is entirely analog (well almost) but the new ones are a mix of analog and digital.

 

[Janger]

@calgaryguy hey Chris I could CAD up a drawing for you and we could potentially drill those bolt holes on my mill. If you wanted to draw the part with dimensions on paper and post pictures I expect it would be quick. And then I could see the machine work?

 

[Janger]

Shop air required.
Probably dry shop air and lots of it. are electromechanical solenoids a substitute for air pistons?

 

[calgaryguy]

@calgaryguy hey Chris I could CAD up a drawing for you and we could potentially drill those bolt holes on my mill. If you wanted to draw the part with dimensions on paper and post pictures I expect it would be quick. And then I could see the machine work?

Is the CAD Step file I posted in my original post modifiable? The B5 D80 side (metric side) needs to be modified to the B5 D71 flange dimensions. @eotrfish posted a measured drawing above that I *think* is right?

 

[calgaryguy]

Probably dry shop air and lots of it. are electromechanical solenoids a substitute for air pistons?

Quite possibly? This is probably the most complex machine I've had my grubby hands into. I've been around cabinet shops but they've always been 'Dont touch it except basic maint, we call the vendor for service' situations.

I have it half disassembled for inspection, cleaning, and de-rusting. I'll snap some pics for peoples interest.

 

[eotrfish]

Is the CAD Step file I posted in my original post modifiable?

Well - sort of

I opened the STEP file and modified the required dimensions. The countersunk holes are boogered in the STEP file so would need to be done correctly. What type of fastener do you plan to use in the 0.385" mounting holes? 82Deg included angle would be appropriate for normal 3/8-16 flat head machine screws. Also the STEP file is done with a mixture of metric and inch dimensions. It would be best if the part was redrawn from scratch - no problem. Let me know if you would like a dimensioned drawing and/or STEP file. Also what thickness would you like the part to be?

 

[Janger]

Well if it is to be drilled on my mill the simplest solution is the all the bolt hole positions in X and Y coordinates from an origin, the centre is probably best.

 

[calgaryguy]

@Janger First off, thanks for everything so far. I think at this point its best if I send you a PM and maybe we can arrange a meet and I can bring what I have and explain the setup and constraints?

 

[calgaryguy]

I'm touching base with Janger in the next while and will update the thread once there is some progress.