What is the difference between a supergrind 2005 and a T-4 and a T-7?

[rhammar]

Can someone tell me the differences or point me to documentation that does ?

[Ken S]

Welcome to the forum, Ross.

The primary difference between the T4 and the T7 or Supergrind 2005 is the diameter of the grinding wheel. The T4 (and also the older T3 and Supergrind 1200 models) have 200 mm (8") diameter grinding wheels. The T7 and earlier models with 2000 numbers have 250mm (10") diameter grinding wheels. At this time, the T4 and T7 are the current models.

Generally speaking, the Tormeks with the larger wheels are designed for heavier duty. The T7 has a number of improvements which have been developed over the years. Part of the Tormek philosophy is that older models should be able to be upgraded with the latest advances.

The smaller series were originally designed for use in Europe. The T3 became available with US comparable  motor. The T4 was a major redesign over the T3. The T4, while not quite as powerful as the T7, is the first smaller Tormek built to professional standards.

If you look at the news archive tab of the tormek.com website, you will see a chronology of recent improvements and model changes. Sharpen a Dull Wit has recently posted an in depth description of the improvements over the years.

This forum is probably the best source of Tormek information.

Ken

[SharpenADullWitt]

The T4 is a smaller unit.  Better in one way (size for transport), no different in some ways (some tools), and worse in others (some tools the wider stone works better on).  Price wise, it tends to be close to a T7 since certain things don't come with it but they do with a T7.  T7 and the 2005 are also rated for heavier duty (no difference to the average homeowner/user, but would be a difference if you ran a sharpening business and didn't leave it for hours on end).
The 2005 is close to the T7, as I thought the T7 came out in 2007.
The 2005 is green, the T7 is blue.
The 2005 is probably the chrome shaft, or at the very early stainless shaft model, where a current T7 has the stainless shaft with tool free knurled nut for removing the stone/lubing the shaft/maintenance.
I believe by 2005, the front tool support had two knobs on it, but it was one knob on that model at some point, the T7 has two.
The 2005 would be out of warranty, where a new T7 would have one.  (basically how close is the price)
The water trough has changed in the last couple of years to a slightly wider one on the T7 (not enough difference for most people to worry about).
One jig, MIGHT be a bit different (don't know when it changed, from the SE-60 to the SE-76) and the 2005 MIGHT have the old bit in the truing jig.

[Herman Trivilino]

The SuperGrind and the T-7 are essentially the same machine. They have a 250 mm diameter grindstone and use the same jigs, etc.

The T-4 has a 200 mm diameter grindstone. It's the little sister. Lighter and more portable. Far less common, especially around here.

[Ken S]

If you bought a new Supergrind back in the day and on the same day bought a new computer, both are probably still working. Tormek and the computer industry have both made considerable improvements over the years. The difference would be that you could retrofit these improvements onto your Supergrind, but not your computer. In fairness, that's a lot of investment in an older Tormek compared to the cost of a new T7, especially this month with the 10% sale.

The main reason the T4 size Tormek is not common in the US is because for most of Tormek history the smaller size was only manufactured with motors comparable with European electric power.

Ken