Forum: Maintenance and Repair Articles
10-06-2013, 07:35 AM
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Modding cheap tripod mounts for other lenses
UPDATE Aug 2021 the previously ubiquitous cheap Alu 65/66mm ID ones have for some reason become much less readily available, and a tenner seems to be now the price rather than a fiver. In fact prices of most seem now to be quite a lot higher (partly due to stricter VAT [sales tax] rules on ebay I think).
There are a range of very cheap, typically Chinese made, alloy tripod collars available. They are often described as being for Canon lenses eg a 66mm ID hinged one is described as for 70-200mm f4/Canon EF 300mm F4L/Canon EF 400mm F5.6L lenses.
UPDATE with a bit of browsing these are some of the ones available. ID = inside diameter; H/NH = hinged/not hinged, price approx in UK£ - UPDATE Feb '17 prices (UK) are higher now. ID: | H/NH | material | Described as for: | price65mm; 66mm | H | Alu | Canon 70-200mm f4; EF 200mm; EF 300mm., EF 400mm | ~ 1068; 69mm | H | Alu | Canon EF 100mm f2.8L macro IS | 7 - 1568.5mm | H | abs | Canon EF 70-200mm f/2.8L USM, Canon EF 70-200mm f/2.8L IS USM | 570mm | NH | Alu | Canon EF 100mm f2.8 IS USM | 1071mm | NH | Alu | Canon 100mm 2.8 micro ("old") | 3 - 472mm | H | Alu | Canon 180mm macro, 65mm macro | 1177mm/78mm | NH | Alu | Canon 70-200mm f2.8 | 5-1081mm | H | Alu | Canon EF 28-300mm f3.5-5.6 | 1081/81.5mm | H | Alu | Canon 70-300mmf4-5.6L IS USM | 10-2080mm/82mm | H/NH | Alu | Nikon AFS 80-200mm | 10-12 | I have found these particularly useful to use, or adapt to use, with my Tamron adaptall lenses. As is the 66mm one is just about spot on to fit around the 01F TC (update most need a little packing). I find they are pretty solid items.
Pic 1 shows a 66mm one modded to fit a Tamron Adaptall 19AH 70-210mm. This lens zooms in moving out (unlike most lenses including most of the other tamron adaptall zooms) so the TM can be mounted in front of the aperture ring at the cost of only restricting the zoom action at the 70mm end. This also fits the 54B 300mm f5.6, the 52A 70-210mm and the 85-210mm. The other lens that benefits in the same way as 19AH is the 60-300mm 23A, which also zooms in moving out (update) though recently I have moved to making a plastic shim to fit the TM on the 23A. Use about 2.5mm thick thermoplastic sheet, warm in the oven, mould around the lens and crank the TM tight on it while it's still soft, allow to cool, trim.
While it is perfectly OK to use eg cardboard, leather etc. as packing to make one of these TM's fit on a lens sufficiently well (I do so myself when the TM almost fits) I like to have a solid, stable fit. This is my relatively quick and easy way of modding eg the 66mm TM down to the ~ 62mm fit of the 23A.
NEED: - LENS, MOUNT
- protective wrap. I use old overhead projector acetate sheet. Polythene, cling film etc all work fine.
- BODY FILLER/STOPPER/REPAIR PASTE eg "isopon" or similar (epoxy based pastes will probably work too but these styrene or polyester based ones are cheaper and easier to work with).
PROCEDURE - Remove the stickyback felt from the mount. To peel it off in one piece and preserve the adhesive on it sufficiently I have usually resorted to warming it in hot water. Recently mounts have had double sided tape holding the felt on, in this case the DSS tape has normally ended up a bit trashed and discarded, and I have had to glue the felt back on or use new sticky back black velour/flocking.
- I also roughen/clean the interior surface of the mount once the felt is removed with sandpaper.
- Size up the mount around the lens and estimate how much filler. Typically something between large marble and golf ball size amount.
- IMPORTANT. don't forget to do this if you don't want the mount permanently attached to the lens. Wrap a layer of cling film around the lens where the mount is going to be used (if you have some familiarity with eg resins etc then yes waxing the lens barrel where it is going to be used as a mould is sufficient). A slight smear of paper glue eg pritt stick is good to keep the cling film in place (easily cleans off after with moistened tissue). UPDATE I am now using some heavy gauge polythene around the barrels - helps to offset the thickness of the felt and makes a smoother finish.
- Mix the filler with catalyst/hardener and smear evenly around the interior of the mount. Go easy on the hardener it's a nuisance if it goes off too quickly.
- Ease the mount into position and close it so that that the filler is moulded to the contour of the lens barrel. Align it square by eye. I find that it's best to close it about half the range on the screw thread, it's easier to sand off a little than to try to tighten the fit.
- Rather than letting the filler harden completely it is better to catch it while it is half hard or "green" - typically 5-30mins depending on how much/how old catalyst, ambient temp etc.. Then it is easy to ease the mount off the lens, peel off the cling film if used, and use a modelling knife to trim off all the excess.
- When the filler is fully hard, sand off any last excrescences and stick the felt back on, with a little glue if necessary. Voila!
PS you can also look at this article; describes making a mount from scratch.
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Forum: Pentax Camera and Field Accessories
12-14-2014, 10:54 AM
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How about the "Vanguard carbon fibre monopod" ?? I think it's very good, add a grip Ball and you're set/ 1.17 pounds , Folded:22&1/2 inches. Max wt load 22# cost: about $100.00
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