Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version 6 Likes Search this Thread
6 Likes  #1
Modding Chinese (and other) tripod mounts to fit eg adaptall lenses
Posted By: marcusBMG, 10-06-2013, 07:35 AM

Staff note: This post may contain affiliate links, which means Pentax Forums may earn a small commission if a visitor clicks through and makes a purchase. If you would like to support the forum directly, you may also make a donation here.


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:price
65mm; 66mmH Alu Canon 70-200mm f4; EF 200mm; EF 300mm., EF 400mm ~ 10
68; 69mmH Alu Canon EF 100mm f2.8L macro IS7 - 15
68.5mm H abs Canon EF 70-200mm f/2.8L USM, Canon EF 70-200mm f/2.8L IS USM 5
70mmNH Alu Canon EF 100mm f2.8 IS USM10
71mm NH Alu Canon 100mm 2.8 micro ("old") 3 - 4
72mmH Alu Canon 180mm macro, 65mm macro11
77mm/78mmNH Alu Canon 70-200mm f2.8 5-10
81mm H Alu Canon EF 28-300mm f3.5-5.6 10
81/81.5mm H Alu Canon 70-300mmf4-5.6L IS USM 10-20
80mm/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:
  1. LENS, MOUNT
  2. protective wrap. I use old overhead projector acetate sheet. Polythene, cling film etc all work fine.
  3. 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
  1. 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.
  2. I also roughen/clean the interior surface of the mount once the felt is removed with sandpaper.
  3. Size up the mount around the lens and estimate how much filler. Typically something between large marble and golf ball size amount.
  4. 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.
  5. 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.
  6. 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.
  7. 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.
  8. 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.

Attached Images
             


Last edited by marcusBMG; 08-06-2021 at 10:24 AM. Reason: formatting
Views: 17,344
10-07-2013, 10:21 AM   #2
Site Supporter
Site Supporter
Lowell Goudge's Avatar

Join Date: Jan 2007
Location: Toronto
Photos: Gallery | Albums
Posts: 17,892
Boy that's a lot of work to achieve what a thick piece of leather can do.
10-07-2013, 12:34 PM   #3
Site Supporter
Site Supporter




Join Date: Nov 2012
Location: North Wales
Photos: Gallery | Albums
Posts: 2,870
Original Poster
QuoteOriginally posted by Lowell Goudge Quote
Boy that's a lot of work to achieve what a thick piece of leather can do.

But at least I don't have to bend over and pick the leather up every time I take the mount off! Or rummage around wondering where my vital bit of leather is when I put the mount on!
10-07-2013, 01:38 PM   #4
Site Supporter
Site Supporter
Lowell Goudge's Avatar

Join Date: Jan 2007
Location: Toronto
Photos: Gallery | Albums
Posts: 17,892
QuoteOriginally posted by marcusBMG Quote
But at least I don't have to bend over and pick the leather up every time I take the mount off! Or rummage around wondering where my vital bit of leather is when I put the mount on!
Ever hi eared of glue on the mount and leather.

That's how I hold it in place. I use a canon 100/2.8 macro mount plus a thick strip of leather on my Q adaptor

10-07-2013, 03:51 PM   #5
Site Supporter
Site Supporter




Join Date: Nov 2012
Location: North Wales
Photos: Gallery | Albums
Posts: 2,870
Original Poster
QuoteOriginally posted by Lowell Goudge Quote
Ever hi eared of glue on the mount and leather.

That's how I hold it in place. I use a canon 100/2.8 macro mount plus a thick strip of leather on my Q adaptor
That sounds great Lowell. Each to his own. Takes about 10 mins to do my trick.
03-16-2015, 10:55 AM   #6
New Member




Join Date: Jan 2015
Posts: 5
A big thank you to marcusBMG for this, in particular the tabulation of the nominal interior diameters of the rings.

Another good option for the lining material is synthetic cork, available from musical instrument repair suppliers in very precise thinknesses.

A less permanent solution would be to slip 3–5 silicon O-rings of the appropriate diameter and thickness around the lens body.

A Very Bad Idea™ is to use rubberbands or strips of inner-tubes — anything latex-based — because such materials are not really solids but rather colloids. In dry weather they will tend to become brittle and crack; in humid weather they will tend to liquify and become a gooey mess.
03-16-2015, 12:15 PM   #7
Site Supporter
Site Supporter




Join Date: Nov 2012
Location: North Wales
Photos: Gallery | Albums
Posts: 2,870
Original Poster
QuoteOriginally posted by leonAzul Quote
Another good option for the lining material is synthetic cork, available from musical instrument repair suppliers in very precise thinknesses.
Yes I'll try that sometime... thanks for the tip.
Sheet Of Woodwind Repair Cork 2mm (Synthetic) 150mm x 100mm: Amazon.co.uk: Musical Instruments

http://www.windplus.net/supplies/best_quality_natural_cork_sheet.html

03-16-2015, 10:27 PM   #8
New Member




Join Date: Jan 2015
Posts: 5
Those look good; just be careful that 'rubberized' doesn't mean literally latex (which has its good qualities, especially for disposables) instead of a more general description of the material as flexible.

And thank you for not slagging me for the silly mistake of typing 'silicon', instead of 'silicone'.

8^0
01-08-2016, 07:43 PM   #9
New Member




Join Date: Dec 2015
Posts: 9
QuoteOriginally posted by marcusBMG Quote
That sounds great Lowell. Each to his own. Takes about 10 mins to do my trick.
I prefer your method as I have tried both
01-09-2016, 05:04 AM   #10
Pentaxian
Jean Poitiers's Avatar

Join Date: Apr 2011
Location: Lost in translation ...
Photos: Gallery | Albums
Posts: 18,076
Thanks for your article, Marcus. Salut, J
10-06-2016, 04:48 PM   #11
Veteran Member




Join Date: Dec 2008
Location: Twin Cities, Minnesota
Photos: Albums
Posts: 650
I have done this four times now.

Since August I have bought 4 of these Chinese tripod mounts for my heavier Adaptall-2 lenses and one Soligor lens. I will post pics as soon as placing items on the Marketplace allows me to get the time.

1: the Soligor 200mm f2.5 lens. I have a mint copy of this one but it's diameter and length makes it heavy enough for this 65 YO to want a monopod or tripods help. This one is also very focus critical with less DOF than I might like but it was part of a bag of Pentax gear from Goodwill so I like it. This mount went around the back of the whole body. There was just enough space between the aperture window and the focus distance window to make it work. It is about 76-77mm and I ordered a mount that did not have the hinge in the middle so it was just a continuous loop of aluminum at about 80 mm. I think those measurements on the 'bay listings are not too accurate. This one was just barely wider than the lens. I took one of those political mailings that are heavy, glossy paper and cut strips off it. Then cut the strips to width and length of the circumference inside the mount ring. One thickness was too little, two almost enough so I added some short pieces about 10mm long in 2 places and it is tight on the lens. The spacers added just enough to allow clear view of both the windows the ring is almost on top of on the lens. Success!!

2: The 75-250 and 60-300 Adaptalls needed a more inventive solution. I used another continuous ring on the larger 300 lens that was smaller in diameter but still had several mm of space open. I have some gasket rubber that was intended for use in plumbing and came in 15 to 18 inch square sheets. I say rubber but it does not compress much at all yet is very flexible. It gets used with old iron or clay pipe I think. I cut strips just smaller than the width of the ring. MarcusBMG had suggested putting the ring on the aperture ring of this lens if I had a PK/A adapter mounted. If you do this you MUST avoid clamping the ring over the release push button for obvious reasons but you also MUST avoid the black AE aperture lock push button. I had to use 2 layers of the rubber inside the ring along with a layer of the thicker paper I used above. Cutting in shorter strips allowed me to leave gaps where the buttons are located. Also with the ring just 1 or 2 mm forward from the buttons on top of the aperture ring insured no accidental dismounts. I did the same with the 75-250 mm lens except I used a smaller hinged tripod mount ring on the smaller diameter aperture ring. Both of these work very well with no slippage of the mounts and no problems in the lens. Success!!

3: I also really like the 52A 70-210mm lens for its so very adjustable macro functions. This unit was almost exactly 65 mm in diameter so I bought a 65mm mount ring. It closed down today around the ring But the fuzzy stuff inside the ring allowed the lens to turn. I used thin strips of paper again, one for each half, and the ring tightened down just fine. Then I took some macro shots of my wife flowers lens pointed almost straight down on the monopod with no slip no problem for 15 minutes of waiting for the breeze to stop moving things between shots. Success!!

So it is possible to buy these tripod mounts sized to fit most any lens and add a little bit of spacers to get a tight fit. However I would be careful about this with any plastic shelled lens but they are not supposed to be too heavy anyway, Right? I had no calipers to determine the diameter of the lenses and it would have helped a lot. I would not trust the fuzzy cushion stuff inside the rings. I think paper directly against the lens will prevent anything from marking or harming the lens but I did not put the rubber directly against the lens and would not advise it. If you do it just go slow till you get each piece and each step figured out.

Good Luck!!
10-07-2016, 04:46 AM   #12
Site Supporter
Site Supporter




Join Date: Nov 2012
Location: North Wales
Photos: Gallery | Albums
Posts: 2,870
Original Poster
Thanks for your contribution Alan, good info.
10-07-2016, 06:33 AM   #13
Veteran Member
Nass's Avatar

Join Date: Aug 2009
Location: The British Isles
Photos: Gallery
Posts: 2,402
Yes, good info, good contribution. Here's a couple of other materials to throw in the mix that might be useful for projects like this. I use them all the time.

1) Moldable plastic. A polymer made out of polycaprolactone (PCL), which is marketed under various names including Shapelock, Thermomorph, Polymorph, InstaMorph, CAPA, Friendly Plastic, the list goes on. Heat up a pan of water and drop it in, the beads then melt, go clear and join together in the pan, you take out the putty-like mass and it can then be shaped and reshaped as you wish whilst warm. When it cools down it retains the solid shape. Doesn't stick though, so I don't know if it is useful or not.

2) Sugru. - malleable when removed from its airtight, moisture-proof packaging, retains its plasticity for thirty minutes, and is self-curing at room temperature in approximately 24 hours. The material adheres to aluminium, steel, copper, ceramics, glass, fabric, brass, leather, plywood, and other materials, including ABS plastics. This stuff is awesome for DIY and camera stuff - shape something that'll go unshapable in 24hr. Lots of colours, small packets though so buy several if you need a collar pad.
10-07-2016, 06:58 AM   #14
Site Supporter
Site Supporter




Join Date: Nov 2012
Location: North Wales
Photos: Gallery | Albums
Posts: 2,870
Original Poster
'
QuoteOriginally posted by Nass Quote
Moldable plastic.
Yes that's interesting Nass. Immediate project comes to mind: tripod mount for my takumar 200mm f3.5. Cheapest supply seems to be 50g multiples @ ~ £1.90ish/50g from HK/China (update: 500g for 13.99 off amazon). How much do you think that might need (this is a preset lens with aperture rings at the front so there is a 2.8cm space by the mount, 18.2cm circumference, ~ 58mm dia)? And do you think this stuff is soft enough and strong enough to mould around and hold a 3/8" to 1/4" TM adapter?
And finally have you ever had any problem with this stuff getting soft eg in direct sunlight?

it also occurs to me that this stuff could be a substitute for the polyester filler I have been using to mod the tripod mount rings.

FYI:

https://en.wikipedia.org/wiki/Polycaprolactone

Last edited by marcusBMG; 10-07-2016 at 07:23 AM.
10-07-2016, 10:37 AM   #15
Veteran Member




Join Date: Dec 2008
Location: Twin Cities, Minnesota
Photos: Albums
Posts: 650
QuoteOriginally posted by Nass Quote
Yes, good info, good contribution. Here's a couple of other materials to throw in the mix that might be useful for projects like this. I use them all the time.

1) Moldable plastic. A polymer made out of polycaprolactone (PCL), which is marketed under various names including Shapelock, Thermomorph, Polymorph, InstaMorph, CAPA, Friendly Plastic, the list goes on. Heat up a pan of water and drop it in, the beads then melt, go clear and join together in the pan, you take out the putty-like mass and it can then be shaped and reshaped as you wish whilst warm. When it cools down it retains the solid shape. Doesn't stick though, so I don't know if it is useful or not.

2) Sugru. - malleable when removed from its airtight, moisture-proof packaging, retains its plasticity for thirty minutes, and is self-curing at room temperature in approximately 24 hours. The material adheres to aluminium, steel, copper, ceramics, glass, fabric, brass, leather, plywood, and other materials, including ABS plastics. This stuff is awesome for DIY and camera stuff - shape something that'll go unshapable in 24hr. Lots of colours, small packets though so buy several if you need a collar pad.
That Sugru sounds like a air or humidity curing epoxy? Also they have poly urethane materials that cure in the presence of air but they usually stay flexible. We sailors use the malleble epoxy stuff that sometimes comes in a carboard tube covered in plastic to fill a small hole in the hull. you can shape it all day in air but once it goes in the water it cures in minutes. Oh, the poly stuff such as 3M's 5200, 4200 series and the underwater epoxy are Very hard to remove. Been there done that have the souvenir piece of the boat hull still attached to the 5200. LOL I don't use that stuff too much now, it is one of the worlds strongest adhesives.

---------- Post added 10-07-16 at 12:58 PM ----------

I'll post a pic of that "rubber" gasket material which should be more available in areas with older plumbing. Using cork would concern me since it can stick to a surface under compression just where you don't want it plus it can dry and become brittle. I have used my sheets of rubber for many applications in heat and severe cold and have had it stick to a surface too. All kinds of ways you can keep that from happening. Automotive gasket material would not be good. Although the automotive gasket materials that come in tubes could be formed, would adhere to the TM and could be kept from sticking onto the lens. Somtimes it is hard to find over a 50g quantity.
Reply

Bookmarks
  • Submit Thread to Facebook Facebook
  • Submit Thread to Twitter Twitter
  • Submit Thread to Digg Digg
Tags - Make this thread easier to find by adding keywords to it!
adaptall, air, film, gasket, hull, lens, lenses, materials, mount, mounts, plastic, post, shape, stuff, surface, tamron, tripod

Similar Threads
Thread Thread Starter Forum Replies Last Post
Camera Mounts for other lenses Raye Pentax SLR Lens Discussion 4 04-07-2012 08:56 AM
For Sale - Sold: Tamron Adaptall-2 28mm f/2.5 lens (02B); also PKA and PK mounts Nick Siebers Sold Items 6 02-27-2012 05:07 PM
Other MF lenses to fit 67? Herb Pentax Medium Format 5 03-17-2010 12:05 PM
Zeiss lenses with CPUs for Nikon other mounts to follow late 2010 PinarelloOnly Pentax SLR Lens Discussion 8 11-18-2009 01:36 PM



All times are GMT -7. The time now is 11:46 AM. | See also: NikonForums.com, CanonForums.com part of our network of photo forums!
  • Red (Default)
  • Green
  • Gray
  • Dark
  • Dark Yellow
  • Dark Blue
  • Old Red
  • Old Green
  • Old Gray
  • Dial-Up Style
Hello! It's great to see you back on the forum! Have you considered joining the community?
register
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]
Top