Make Your Own Tripod Platform Retainer

There have been discussions in this forum about the head platforms on Gitzo Series 3 and 5 Systematic Tripods falling out of their mounts with potentially disastrous results. NatureScapes now offers a machined metal retainer that will prevent accidental release of the platform head. However, the price for this metal doughnut -- typical of anything that is considered "photographic equipment" -- is nearly $70. I just made an alternative that cost me $1.76, and performs just as well:

For a Series 3 Gitzo platform get a scrap of 1/4" marine grade plywood.
Tools: compass, ruler, coping sawDrill with 3/8" bit, wood rasp and/or sandpaper.
Materials:
One 4" X 4" piece of marine grade 1/4" plywood
One stainless 3/8" - 16 cap screw 3/4" long
One stainless fender washer with 3/8" hole
Polyurethane varnish

The retainer dimensions are larger for the Series 5 tripods, but the principle is the same.

Hi Craig, interesting idea, I had also thought of doing something similar but have been put off by not knowing enough about 'engineering' to pick a bolt (you have used a stainless 3'8 bolt and washer) that I know will take the enormous shearing stress of a gimbal/500f4 and camera when carrying over shoulder.

Tell

Thanks for humorously pointing out my typo, Tell. I didn't mention the cost of the fork lift needed to carry a 3'8 bolt to the photo site. (I've now corrected the typo in my original post.)

A 3/8" diameter screw is, of course, the standard size for pro mounts, including the bottom hole in the Gitzo platform. Just be sure the thread pitch matches before screwing it fully into the tripod. Forcing a bolt with the wrong pitch will trash the threads in the tripod! If you get resistance when you try screwing in the bolt, the thread is wrong. Best bet is to take your tripod to the store and try for correct fit.

Don't you also mean a "9 cm circle"? :)

JR

Quote:

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Originally Posted by Craig Markham

Thanks for humorously pointing out my typo, Tell. I didn't mention the cost of the fork lift needed to carry a 3'8 bolt to the photo site. (I've now corrected the typo in my original post.)

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You will laugh at this then Craig - I didnt see your typo and really meant what I said - LOL - I was trying to say that I am unsure what 'specification strenght' bolt to get because the load must be quite high, obviously a brass bolt would shear but I do not know how to ask for a bolt strong enough for the purpose ? Is just asking for a 'stainless steel' bolt good enough, obviously with the right thread ?

Tell

Ask for a Grade 5 or if you want it real strong ask for Grade 8. They will have a symbol on the bolt head that will show you which is which.

http://www.rockcrawler.com/techrepor...ners/index.asp

There are many grades but the 5 and 8 can be found at most good hardware or automotive stores. Stainless is not really for strength but more for rust protection.

Bill

Make sure the thread pitch is 16. The tripod mount machine bolt is a 3/8 - 16 thread. If any of you missed the well engineered and machined plate retainer designed by a couple of serious photographers here is a link.

http://www.naturescapes.net/store/pr...?productid=453

Cheers,

Jim

Thanks, Bill,Tell and Jim, I've gone back and corrected the dimensional units in the original post above. I wrote the post at 1:00 AM last night; it looks like fatigue gained the upper hand on me!

RE the bolt strength, I think the plywood piece would fail before the bolt, regardless of grade; that's why I recommend a high grade plywood and large OD backing washer. Unless you're carrying a small SUV on your tripod, I don't think there's anything to worry about.

The retainer is an insurance policy, not an optical element. No matter how well-engineered, it doesn't have the visibility to wow the crowds as a fashion statement. It just has to keep my equipment on the tripod.
-- Craig

I have to say if I were to spend upwards of $750.00 for a tripod, I really do not feel like I still have to have it make due. Gitzo seems to be having quality issues, so until I hear differently, I will stay away, far away.

Cheers

Nancy, I kept this in mind as I photographed fireworks this weekend -- from the 19th floor balcony railing of a condo high-rise! I agree that Gitzo showed an abysmal lack of foresight in the design of the platform retention feature, and it seems silly that we should have to come up with our own retrofits for make up for that. That said, I am otherwise very happy with the performance of the tripod.

Here's a photo of my retainer.