Before using this site please read the site disclaimer. Also please note that any links provided may be part of an affiliate programme (viz. eBay, Amazon) which helps support the site as I will earn a commission when visitors make a qualifying purchase.
This is all the information I have with regard to dating GMF tools and equipment.
Rowan sent in some interesting information regarding dating the GMF bench grinders. He was looking at the capacitors and found that some were made by Ducon, which have a date code in 3 numbers stamped into them (w/yy), though of course given the age it can sometimes be illegible or rubbed off. They're rectangular folded capacitors containing PCBs. Ducon apparently went out of business in 1963, and more modern GMF grinders have cylindrical capacitors in them.
Rowan has a 7" 1/2hp Industrial grinder with serial number 2121139 that has a capacitor inside with the date code of 1961.
Nock and Kirby show the Junior in 1954, and it's featured in the 1959 catalogue and in the 1967 Scruttons catalogue. It's not seen in the 1977 catalogue and I suspect it was deleted earlier in the 70s.
The 1966 McPhersons and 1967 Scrutton shows an 8" Senior grinder.
These were shown in the 1959 GMF catalogue, along with the 1966 McPhersons and 1967 Scruttons but were not shown in the 1977 listings.
The 1970s McPhersons show the 8" Heavy Duty Mark 5 grinders in single (¾hp) and three-phase (1hp).
Shown in the 1970s McPhersons. Single phase, ¼hp.
Shown in the 1970s McPhersons. No mention of Mark 3 or 5. ⅓hp single phase unit.
Rowan has sent in some pictures of a 7" Industrial Grinder with a capacitor inside it that has a 1961 date. This model is also shown in the 1970s McPhersons. Single phase only, ½horsepower. 7x1x⅝" bore.
Shown in the 1970s McPhersons catalogue. Single phase only, ½hp. Also shown in the 1972 Power Farming magazine.
The 1970s McPhersons catalogue shows the 10" Maxi Grinder in single phase 1¼hp and three-phase 1½hp variations. The wheels were 1" and 1½" wide respectively with a 1" bore. Also shown in the 1972 Power Farming annual.
This one was made in Singapore. The GMF Singapore factory appears to have opened in 1976, so I would date this model to no earlier than that.
Shown in the 1984 Power Farming magazine in single and three-phase. Timothy sent in a picture of his which has a Betts-branded plate (making it post-early-1980s), showing 750W of power:
Shown in the 1984 Power Farming magazine in a Betts advertisement, available in single and three-phase. Stated to be the most popular model.
Hugh sent in photos of one he has that was purchased in 1981 - note the horsepower measurement and pre-Betts plate:
Shown in the 1984 Power Farming magazine in single phase only. Says it's the original GMF grinder updated for the 1980s.
Shown in the 1984 Power Farming magazine in single phase only.
Shown in the 1984 Power Farming magazine in single and three-phase. Stated to be Australian made. Some plates show a horsepower rating, some in watts! Timothy sent in some pictures of his 240v 250mm Maxi plate, serial 945827:
939 watts, which is about 1.25hp. The plate shows Betts, which makes it post-early-80s.
The 1st May, 1959 catalogue lists the following:
The 1959 catalogue states that the Caddie was a then-new range of sub-fractional shaded pole motors and that they had been developed for applications such as air circulating fans and room coolers, fan heaters, oil burners, humidifiers, animated signs and small centrifugal pumps. It was available in a drip proof, a totally enclosed design and in an open bracket design with a choice of sleeve or ball bearings, except for the open design which had sleeve only. Output was up to 1/50hp at 1300rpm but it was also available in multi speed.
The 1959 catalogue also showed a metal disintegrator.
In 2019 the server has had to double in capacity to support the growing site... please consider dropping the site a donation to help cover the costs! Check out our Patreon for support options, buy a shirt, buy our apps, use my NordVPN affiliate link to sign up to their service or donate via Paypal:
| Paypal $5 link ->> | |
| Paypal $10 link ->> |