Best 1/4" to 3/8" adapter?

[Greg]

One of my high quality ball heads does not offer an OEM 3/8" tripod screw option. The only way to go is to get a 1/4" to 3/8" adapter. I have a few older ones but not that high of quality and the brass one scares me a bit to use. I would assume that a SS 1/4" to 3/8" adapter would be the best way to go or ? Can anyone recommend a high quality 1/4" to 3/8" adapter?

Only a personal observation, but 1/4" tripod screws seem to now dominate the current market. Probably just the result of digital cameras vastly outnumbering LF cameras...

[Drew Wiley]

There are different qualities of brass. But long ago mechanics and machinists discovered that it's important to preserve a primary thread by using something potential sacrificial and a little softer for the secondary thread. I don't always follow that advice myself, and generally use stainless steel instead because our marine atmosphere around here inevitably corrodes even brass or chrome to a significant degree. The local camera store sells perfectly decent adapters. But if you want a good selection of all kinds of alloys, go to any real machinist supply (if any are open at the moment), or to the McMaster Carr website. You'll pay far more for the shipping than the item itself, unless they only package it in multiples, which might make sense to have around anyway.

[Jeff Keller]

If you get one with a large flange, you won't have to worry about it getting stuck in your tripod head.
https://www.bhphotovideo.com/c/product/850351-REG/impact_ca_113_1_4_20_female_to_3_8_16.html
(I would remove any rubber pad) I tried a couple different brands and one of them had very few threads.

Probably getting one, with as many threads that will go into your tripod head as possible and still be flush, is as important as the material. Some of the adapters are short so that they are guaranteed to screw all the way in, but all the way in has very few threads. If you don't get one with a large flange, pay attention to the outside end which may have a small squared off or beveled flange. If you have to use one with a small beveled flange so that it will mount flush with your tripod head, removing it may take more than the appropriate size of screwdriver.

[Pieter]

If you get one with a large flange, you won't have to worry about it getting stuck in your tripod head.
https://www.bhphotovideo.com/c/product/850351-REG/impact_ca_113_1_4_20_female_to_3_8_16.html
(I would remove any rubber pad) I tried a couple different brands and one of them had very few threads.

Probably getting one, with as many threads that will go into your tripod head as possible and still be flush, is as important as the material. Some of the adapters are short so that they are guaranteed to screw all the way in, but all the way in has very few threads. If you don't get one with a large flange, pay attention to the outside end which may have a small squared off or beveled flange. If you have to use one with a small beveled flange so that it will mount flush with your tripod head, removing it may take more than the appropriate size of screwdriver.

I have the opposite problem: most adapters are too long and protrude beyond the camera base. Also, I prefer ana adapter that has a slot cut into it so I can remove it with a flat-blade screwdriver.

[Bob Salomon]

The best is the LInhof brass one.

[Pieter]

The best is the LInhof brass one.

And the Gitzo one?

[Drew Wiley]

A trick I use in this instance and numerous analogous applications is to use a little wrap of plumber's teflon tape around the outer threads (preferably the yellow gas line type). This prevents the insert from corroding itself shut within the tripod socket, and also makes it much easier to remove when necessary, yet without easily getting loose and falling out. Remember, even if you have an inert alloy in the case of the reducer itself, most tripod heads themselves are aluminum alloys capable of corrosion. Just hang around the beach frequently if you doubt that fact. Even the anodized aluminum trim on my slider windows is now a corroded greenish mess. Time takes its toll; yet I happen to like lifetime gear, and therefore appropriately care for it.

[Bob Salomon]

And the Gitzo one?

Not as good. Too long.

[William Whitaker]

Unless it's totally loosey-goosey and ill-fitting, I would not run screaming from your brass adapter. If you're speaking of the threaded bushing type of adapter which threads into the camera's mounting hole and provides a receptacle of the correct diameter and pitch, then it's going to operate under compression anyway and the strength of the brass won't be an issue. Besides, brass will not gall with other metals, so little chance of it getting stuck.
There's probably a reason that Linhof chose brass for their offering.

[Christianganko]

I was in this situation last week.

I got my new / old linhof back from the cla and tech told me not to use adaptors.

The technika has a 3/8but my ball head arca style release plate has a 1/4

I went onto Amazon and purchased a 3/8 release plate for $14

I have to day I feel much more comfortable.

[Greg]

The best is the LInhof brass one.

Found two Arca-Swiss 8mm 3/8"-16 to 1/4"-20 adapters that I had bought years ago, never used (still in original packaging), but stored and forgot about. They look to be a lot, I mean a lot better than my 4mm generic brass bushings that I just didn't trust to do the job. Also looks to me that there are different hardnesses of brass out there? Arca-Swiss quality and machining has to be akin to Linhof's from what I can tell. Ended up throwing away a couple of them that were between 4-5mm in "height".
Thanks to everyone who posted...

[Drew Wiley]

There's brass, and then there's brass. It's not all the same. Some types machine well and are relatively durable, some are not. Linhof is very familiar with the reason for using die-cast alloys, as would be most Euro manufacturers. Generic substitutes made in China, well, you take your chances; they might even be zinc "pot metal".

[reddesert]

Brass is a good material for this kind of application because it is resistant to galling. Brass typically has good machinability and ductility, which is why it is resistant to galling, and why it is often used for bushings, etc. Obviously there are many different types of brass alloys, but these are applicable to most. Compared to other materials, brass is for example weaker than steel and heavier than aluminum, but this is an application where maximum material strength isn't as critical, *if* you screw enough threads into the adapter. Sometimes, even the tripod screw itself appears to be made of a brass or bronze. I'm sure the number of threads and the quality of the machining matter.

[Tin Can]

Bob, I often buy from reputation

I will buy a $30 Linhoff just to test it

I have been using Wimberley BS-100 3/8"-16 to 1/4"-20 Brass Reducer Bushing $4

Arca-Swiss Adapter Screw 8mm 3/8"-16 to 1/4"-20 Reducer Bushing $10


The best is the LInhof brass one.

I really like the Latest, perhaps old Deardorff method that adapts from inside the camera

I have chipped broken diecast crap out after it broke

I vastly prefer to switch the tripod male screw

The best design and adjust for length are the Majestic screws, also spring loaded popup and long enough even for a KMV

I bought the last 2 inventoried Majestic at the last warehouse from the last owner by telephone, not that long ago

in box

[Greg]

Found two Arca-Swiss 8mm 3/8"-16 to 1/4"-20 adapters that I had bought years ago, never used (still in original packaging), but stored and forgot about. They look to be a lot, I mean a lot better than my 4mm generic brass bushings that I just didn't trust to do the job. Also looks to me that there are different hardnesses of brass out there? Arca-Swiss quality and machining has to be akin to Linhof's from what I can tell. Ended up throwing away a couple of them that were between 4-5mm in "height".
Thanks to everyone who posted...

Available from B&H: Arca-Swiss Adapter Screw 8mm 3/8"-16 to 1/4"-20 Reducer Bushing BH #ARB.2538 • MFR #809011
Just ordered 2 spares.

[Drew Wiley]

I think that if Linhof sold you their bushing in a paper bag they'd charge you an extra $30 for the bag itself if their own name and logo was on it. I have no idea what the distribution markup is, other than ridiculous, but it's hard to imagine that something like the bushing in question originally cost more than fifty cents to make, no matter how allegedly good.

Tin Can - you are obviously using the terms "diecast" in a very different manner from me. I've sold literally tons of the real deal. It's an entirely different kind of brass alloy especially high in copper content, and the billets are put under extreme pressure to force out all the voids and impurities. It's very strong stuff and machines well, but is not equal to most bronze alloys. Much the the brass gearing and hardware I've personally seen on field cameras is actually a very inferior kind of brass. And most of the hardware store style reducing inserts are more in the "basement of junk" classification rather than marginally respectable ground floor junk itself.

[RivetGun]

For what it is worth silicone bronze is stronger than brass and the threads will last longer. It is sometimes used in threaded machine tool carriages.

The main thing with threads (or bushings supporting rotating shafts) is to use different types of metal or different hardness. In other words aluminum on aluminum or stainless on stainless or very hard steel on very hard steel will quickly destroy each other. Aluminum on stainless will last a long time.

[Bernice Loui]

There are various grades of bronze from silicon to zinc to marine specific bronze to bearing bronze. Majority of them are higher strength than brass.

Aluminum alloys can be higher strength than brass (7xxx series and others)
Aluminum on Stainless steel is a recipe for galvanic corrosion that can wreck havoc on the parts involved.

Fact is, these thread adapters are not that highly stressed making common yellow brass more than good enough for the stress they are will be subjected to in service. That said, Aluminum is a gosh awful material for threads. It has a fabulous tendency to gall, has an ill-defined yield point or where it begins to bend-stretch-give is variable and not well defined. High strength Aluminum alloys tend to be brittle with a similar fondness for galling.

Stainless steel is available in a variety of types, some are not as high strength or corrosion resistant than is believed, other grades of stainless steel are magnetic (4xx series), some are not. Some are extremely corrosion resistant (316, 321 and related), some are far less so.

There plenty of exotic alloys that far exceed the application demands for any 3/8-16" to 1/4"-20 tpi adapter, reality is, these exotic materials cannot make a technically proper justification for their usage in this application.


Bernice



For what it is worth silicone bronze is stronger than brass and the threads will last longer. It is sometimes used in threaded machine tool carriages.

The main thing with threads (or bushings supporting rotating shafts) is to use different types of metal or different hardness. In other words aluminum on aluminum or stainless on stainless or very hard steel on very hard steel will quickly destroy each other. Aluminum on stainless will last a long time.

[Drew Wiley]

One simply does not want something especially hard or strong. The whole point is that if something gives over time, it should be the insert device itself rather than the primary thread. Same goes for cable release materials, filter ring material etc. But the alloy does need to be consistent and reliable. Cost has damn little to do with it. Machinability does. Visit any marine supplier and see how much people are willing to spend on even a tiny silicon-bronze tie cleat. I have one on each leg of my Ries tripod for hanging the light meter, loupe, etc. I once managed the biggest selection of forged bronze and brass hardware on the West Coast, plus a lot of stainless too. Single sales tabs in the twenty to forty thousand dollar range were routine. A past era - now most items are melt-cast junk alloy instead.

[BrianShaw]

Wiser words have rarely been written:

“ Fact is, these thread adapters are not that highly stressed making common yellow brass more than good enough for the stress they are will be subjected to in service. ”

I think all that I use are stainless but that’s only because they were cheap and easy to source.

Why over-think this????

[Drew Wiley]

Why not? If this were a bass fishing forum, we'd be discussing hook alloys.