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View Full Version : Frankensinar: upgrading the F/F1 front standard



fishbulb
30-Jan-2015, 18:19
Well, I broke my Sinar F front standard. Due to the design of these, they can easily be broken if over tightened, or even just during regular use due to the 30 year old plastic and the thinness of the weak area.

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So, after reviewing the Sinar F service manual I devised a plan to buy an extra Sinar F rear standard and convert it to work as a front standard. There are several ways of doing this, including just putting the extra rear standard on the front and connecting the bellows. Easy to do, no tools needed, but all the knobs are on the wrong side. So I decided to use the original front frame, and connect it to the monorail clamp of the extra rear standard.

When my eBay rear standard arrived, however, there was a surprise. I didn't notice it in the photos, but this rear standard was slightly different than my old one. Sinar must have changed the design mid way through it's life. Indeed, the service manual confirms this. So ideally, try to find a rear standard the same as your old one.

As shown below there are subtle differences. More Phillips screws, black instead of aluminum screws and sides, and most importantly the gear scale is on the opposite side of the rail clamp! Oh well, live and learn. One big advantage of the first generation F standard is that it has about 1.5cm more right shift on the rear standard (4.5cm vs 2.5cm) because the first generation F lacks the umbrella attachment hole (for a compendium shade or whatever accessory you'd put here). Note that these are both F standards, not F1 or F2 standards.

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fishbulb
30-Jan-2015, 18:19
Anyway, first thing to do is get a heat gun or hair dryer and heat up these screws on the bottom of the rise/fall rails. These screws are held in with Loctite 221, which needs a little heat to get loose. This is in the loctite specs as well as the Sinar F service manual. I omly heated each one for about 30 seconds. Then grab them with a pair of pliers and some rubber (I used a piece of an old bicycle inner tube to pad the pliers).

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Then just unscrew them and repeat the process for both the old front standard and the second rear standard (four screws total). From there you can swap the rear monorail clamp onto your original front standard rise/fall rails. Don't loose the little grey piece of plastic that goes between the rise/fall rail and the screw that is used to clamp down the rise/fall of the standard. It protects your rise/fall rail from getting scratched and dented by the rise/fall clamping screw).

Next you have to swap the tilt lever from the second rear standard onto your front standard. As shown in the photo below (of the completed project), you need the longer bolt to clear the microfocus knob. This bolt can be removed just by unscrewing the end cap screw with a coin, and then backing out the bolt all the way.

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fishbulb
30-Jan-2015, 18:25
Here are some photos of the finished product. Note that if I had been more careful and bought a matching rear standard instead of a later production one, the micro focus rulers would be on the same sides for both standards.

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The only major disadvantage of doing this is that you loose about 10mm of bellows compression. Here is a picture for comparison, with me holding the original front standard (with holes in it) next to the installed replacement front standard. As you can see, the original front standard could get a little closer to the rear standard, by about 10mm. This would only be relevant with a bag bellows, as the normal Sinar bellows will not allow even the amound of compression shown in the picture.

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Ideally, of course, you'd just buy a Sinar F2. But they sell for double to triple what an F or F1 sells for, and in my opinion, I like the retro aluminum colors of the original F vs the all black F2.