In need of more cramps and gasping at the price of the market leader, I chanced my arm on a dozen Silverline Expert 900mm at £7.70 each (inc VAT), well under 1/3 of the price of the Records, (which are now made in China for Irwin). What did I get?
As you might expect, at this price you don't get perfection! The cramps looked the part, but close examination shows some carelessness. In every case, the clamping load was taken by the small pin that retains the moving head to the screw. This was bound to fail or jam, but easily cured by removing the pin and inserting between 2 to 4 washers (as spacers) under the end of the screw. The sole purpose of the pin is to retract the head (and also stop it falling off the end of the screw). A split pin would be a good idea, in case the washer spacer wears a bit and needs further attention. The cramp was unlubricated, I left the rolled acme thread dry (PTFE spray) and put a big blob of grease under the screw head.
The cramps work well, despite the parts being somewhat loose on the bar - this disappears as soon as the slack is taken up. A nice feature, the cramping surface is quite large (45x50mm) and machined flat, so it's easy to fit wooden cheekpieces with double sided tape if needed.
At this point, Rutland reduced the price of their blue "made in the same factory as the market leader" cramps, making them about the same price as a similar length Silverline. I ordered 12 of these (54" or ~1400mm) at the sale price of a tenner each. How did these compare? At first sight these look a little better made, but Records they ain't.
The bar is the same size as the Silverline, (the usual 1/4"x1 1/4") and plated, the screw similar but very greasy, and the pinning of the moving head to the screw looks better. However most cramps needed a washer spacer to stop tightening mangling the retaining pin. There's less play in the moving parts. The heads are lighter, and the working face of the cramp is a lot smaller (28x48mm) and is not machined flat (evidence of hand grinding to remove flashing) so not very easy to add wooden cheekpieces or even cork sheet. Some of the bars had been bent by hole punching and had to be straightened. The "Same factory" story may well be true, but very definitely meaningless hype.
Both cramps have the adjusting pin on a short length of steel cable (bowden/cycle brake inner). This looks cheap but is quite efective as the spring of the cable can be used to stop the pin falling out! Traditionalists will have to get some galv'd jack chain (for hanging industrial lighting) from an electrical factors, around a fiver for 10M.
All cramps, including Records, will bend under load. To prevent the work popping out with a loud bang (!) it shoud be supported separately from the cramp bar. The work should also be at a height to be centred on the cramping screw, with triangular clamping blocks as illustrated in David Charlesworth's book.
Value for money? I would have been very unhappy to pay the full £20 for the Rutland, but ~£10 each (sale price) OK. The Silverline, despite the need for fettling, still look good value against the Record. Now also made in China, the Record may not be all it was either... Both cheaper cramps have a lifetime g'tee. If I needed more, at these prices I think it would be the Silverline.
As you might expect, at this price you don't get perfection! The cramps looked the part, but close examination shows some carelessness. In every case, the clamping load was taken by the small pin that retains the moving head to the screw. This was bound to fail or jam, but easily cured by removing the pin and inserting between 2 to 4 washers (as spacers) under the end of the screw. The sole purpose of the pin is to retract the head (and also stop it falling off the end of the screw). A split pin would be a good idea, in case the washer spacer wears a bit and needs further attention. The cramp was unlubricated, I left the rolled acme thread dry (PTFE spray) and put a big blob of grease under the screw head.
The cramps work well, despite the parts being somewhat loose on the bar - this disappears as soon as the slack is taken up. A nice feature, the cramping surface is quite large (45x50mm) and machined flat, so it's easy to fit wooden cheekpieces with double sided tape if needed.
At this point, Rutland reduced the price of their blue "made in the same factory as the market leader" cramps, making them about the same price as a similar length Silverline. I ordered 12 of these (54" or ~1400mm) at the sale price of a tenner each. How did these compare? At first sight these look a little better made, but Records they ain't.
The bar is the same size as the Silverline, (the usual 1/4"x1 1/4") and plated, the screw similar but very greasy, and the pinning of the moving head to the screw looks better. However most cramps needed a washer spacer to stop tightening mangling the retaining pin. There's less play in the moving parts. The heads are lighter, and the working face of the cramp is a lot smaller (28x48mm) and is not machined flat (evidence of hand grinding to remove flashing) so not very easy to add wooden cheekpieces or even cork sheet. Some of the bars had been bent by hole punching and had to be straightened. The "Same factory" story may well be true, but very definitely meaningless hype.
Both cramps have the adjusting pin on a short length of steel cable (bowden/cycle brake inner). This looks cheap but is quite efective as the spring of the cable can be used to stop the pin falling out! Traditionalists will have to get some galv'd jack chain (for hanging industrial lighting) from an electrical factors, around a fiver for 10M.
All cramps, including Records, will bend under load. To prevent the work popping out with a loud bang (!) it shoud be supported separately from the cramp bar. The work should also be at a height to be centred on the cramping screw, with triangular clamping blocks as illustrated in David Charlesworth's book.
Value for money? I would have been very unhappy to pay the full £20 for the Rutland, but ~£10 each (sale price) OK. The Silverline, despite the need for fettling, still look good value against the Record. Now also made in China, the Record may not be all it was either... Both cheaper cramps have a lifetime g'tee. If I needed more, at these prices I think it would be the Silverline.
