- Joined
- Dec 11, 2000
- Messages
- 1,082
An update for folks.
My Reeder Grinder arrived last week!
On Friday I bought an IEC motor, a nice new Brook Crompton, from one of the actual bricks and mortar businesses I found after Pinoy poked and prodded me hard enough to look. W.H. Shoebridge & Sons ltd (est 1919) in Northampton. Helpful chap named Deryck helped me out. Cost £252 inc tax.
....and very disappointingly I shall be returning it this coming Friday since it is now clear that getting it to fit is not just awkward, but possibly risky, or uneconomical
In all the above discussion, I was concentrating on the diameter of the motor spigot, the bolt circle and shaft output diameter. I was willing to try a less than ideal mounting that would involve making up a spacer donut for the spigot and disassembling the whole grinder in order to drill a smaller ring of mounting holes. That was going to require making a filler piece to drill through so the drill would not wander as it broke through half of the existing mounting diameter.
The problem I didn't see was that while the NEMA shaft is 2.06" long, and the IEC shaft is 50mm long, the NEMA uses a key way cut to the very end of the shaft, and the IEC uses a pocket mounted key. That means the IEC key doesn't get up to full width until about 8mm back from the end of the shaft. With the mounting location of the drive wheel (that I had not considered) and the location of the mounting set screw in the wheel (that I hadn't considered and didn't have a dimension for) the set screw sits right on the radiused nose of the key. Also, the larger diameter of the IEC shaft meant it was engaged by only 1D compared to a NEMA shaft being 2D, which just looked wrong.
I spent much of the weekend looking at ways to make the IEC fit better and earlier today I called Shoebridges and discussed options. They suggested that they could make up a longer shaft, but that the making and fitting could add £300 to the original price. If I was having a longer shaft, I would want an extra 3/4" at least. Not having a lathe, or mill, I cannot turn my own shaft extender, nor extend the keyway, and both of those seemed like a bodge job too far.
Since I recently started a new job, right now I don't have the time or energy to put into adapters and modifications if the shaft mounting is going to be questionable. Its enough to need to build a new bench and re-arrange my shop to accommodate a new grinder. So I have ordered a Leeson 2HP 3PH from the US and will be getting a refund on the Brook Crompton later this week. At least I had the foresight to order a 5/8 bore drive wheel with the grinder as well as the 24mm special!
Live and learn.
All the best
Chris
My Reeder Grinder arrived last week!
On Friday I bought an IEC motor, a nice new Brook Crompton, from one of the actual bricks and mortar businesses I found after Pinoy poked and prodded me hard enough to look. W.H. Shoebridge & Sons ltd (est 1919) in Northampton. Helpful chap named Deryck helped me out. Cost £252 inc tax.
....and very disappointingly I shall be returning it this coming Friday since it is now clear that getting it to fit is not just awkward, but possibly risky, or uneconomical
In all the above discussion, I was concentrating on the diameter of the motor spigot, the bolt circle and shaft output diameter. I was willing to try a less than ideal mounting that would involve making up a spacer donut for the spigot and disassembling the whole grinder in order to drill a smaller ring of mounting holes. That was going to require making a filler piece to drill through so the drill would not wander as it broke through half of the existing mounting diameter.
The problem I didn't see was that while the NEMA shaft is 2.06" long, and the IEC shaft is 50mm long, the NEMA uses a key way cut to the very end of the shaft, and the IEC uses a pocket mounted key. That means the IEC key doesn't get up to full width until about 8mm back from the end of the shaft. With the mounting location of the drive wheel (that I had not considered) and the location of the mounting set screw in the wheel (that I hadn't considered and didn't have a dimension for) the set screw sits right on the radiused nose of the key. Also, the larger diameter of the IEC shaft meant it was engaged by only 1D compared to a NEMA shaft being 2D, which just looked wrong.
I spent much of the weekend looking at ways to make the IEC fit better and earlier today I called Shoebridges and discussed options. They suggested that they could make up a longer shaft, but that the making and fitting could add £300 to the original price. If I was having a longer shaft, I would want an extra 3/4" at least. Not having a lathe, or mill, I cannot turn my own shaft extender, nor extend the keyway, and both of those seemed like a bodge job too far.
Since I recently started a new job, right now I don't have the time or energy to put into adapters and modifications if the shaft mounting is going to be questionable. Its enough to need to build a new bench and re-arrange my shop to accommodate a new grinder. So I have ordered a Leeson 2HP 3PH from the US and will be getting a refund on the Brook Crompton later this week. At least I had the foresight to order a 5/8 bore drive wheel with the grinder as well as the 24mm special!
Live and learn.
All the best
Chris
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