[TwoUptons]

So my Tokina 400mm f5.6 (the old RMC manual focus one) has fungus on an inner element.

I’ve used my spanner (the kind that looks like #) to remove the rear element, but the spanner won’t fit that far down into the lens to get the next one.

I tried a pair of dividers and they wouldn’t clear, either.

And the two screwdrivers trick gets me into the slots, but I can’t put any torque on them...

Is there anything I’m overlooking? Or an alternative tool I should try?

For my next go, I’m going to try a credit card cut to size, but I’m not optimistic

-Eric

[marcusBMG]

This lens is found in various incarnations: tokina, hoya, mitsuki and vivitar TX v2. I had the rear element off my viv easily enough, it unscrews complete with rear baffle. I take it you're trying to get at the next element in. Like you my straight ended lens spanner won't do it, not without taking off all the mount to improve the access (why didn't I get one with curved ends?). I think that's what you have to do, or successfully improvise (an old steel workshop 12" ruler, trimmed to fit...).

[AstroDave]

Have you got a friend with a machine shop? You could have something fashioned out of a piece of metal - rather like the credit card you are imagining, but a lot stiffer & stronger. Or, try to find a thicker piece of plastic from which to fashion it.

[Not a Number]

Use a couple pieces of wood, a couple small C-clamps or nuts and bolts to hold the two screwdrivers together.

[AstroDave]

I think Not a Number might be envisioning something like this.

I conjured this up when I had to remove the nut from my toilet tank to toilet bowl connection. The span is more than 2 inches, and I had no wrench large enough. The metal pieces are aluminum bar stock about 1/8" thick and 1/2" wide. (The holes in the block of wood are from another project - but drilling something like that to hold your screwdrivers might be just the ticket.)

(Sorry 'bout the Canon picture!)

[TwoUptons]

I think Not a Number might be envisioning something like this.

I conjured this up when I had to remove the nut from my toilet tank to toilet bowl connection. The span is more than 2 inches, and I had no wrench large enough. The metal pieces are aluminum bar stock about 1/8" thick and 1/2" wide. (The holes in the block of wood are from another project - but drilling something like that to hold your screwdrivers might be just the ticket.)

(Sorry 'bout the Canon picture!)

That's an interesting approach.
I'll have to see if I can find something that can get all the way in there, be thin enough to fit the slots, and be strong enough to not bend...

I may have to find some metal and cut it to size instead.
I tried the credit card (thanks, Visa, for the new card this month...) method, but the plastic isn't rigid enough and just bends until it falls out of the slot.
But the card may be perfect as a template...



---------- Post added 08-17-19 at 08:25 AM ----------

Have you got a friend with a machine shop? You could have something fashioned out of a piece of metal - rather like the credit card you are imagining, but a lot stiffer & stronger. Or, try to find a thicker piece of plastic from which to fashion it.

"Have you got a friend with a machine shop" is like the engineer's version of "hey, hold my beer while I..."

Though I guess the real engineer's version is "do you like this new $3,000 machine? I needed it to make this $3 tool..."

I don't, but my mother has a bench grinder, and I have a dremel, so if I can find the right piece of metal stock to turn into a tool...

-Eric

[c.a.m]

Is there anything I’m overlooking? Or an alternative tool I should try?

I needed a narrow, long-tipped spanner for a repair job on a rangefinder (Olympus or Canon, don't recall exactly).

One of my lens spanners of the '#' variety has interchangeable tips. Similar to this: https://www.amazon.com/Neewer-Camera-Lens-Openning-Repairing/dp/B0734PH87W/r...gateway&sr=8-7


I bought two inexpensive small screwdriver sets, and modified the smallest driver to make two custom tips for the spanner.

There are many such 'precision' screwdriver sets; here's an example:6PCS Mini Screwdriver Set with Case, Precision Screwdriver Kit with 6 Different Size Flathead and Phillips Screwdrivers, Perfect mini Screwdriver Bits for Jewelry, Watch, Eyeglass Repair. - - amazon.com?tag=pentaxforums-20&

Select the driver size for which the knurled shaft will fit the spanner (there may be a slight slop in the fit, but the spanner screw will tighten it). Cut the knurled shaft to an appropriate length, and modify the tips for your purpose -- use a Dremel tool.

The drivers are not high strength -- what do you expect for $5? -- but mine worked fine for my job. This approach could work on your lens, depending on the reach that you need.

- Craig