I uh, broke my TAL-M long handle - Help! (Solved)

[marcelteaching]

To my credit - It's not entirely my fault.  I managed to aquire a used one, but someone tried to use the long handle as a lever, and of course, bent it so severely it could barely rotate anymore.

DaveL59 was kind enough to help me get it apart, but at precisely the wrong moment, it gave way and broke off.  Now I have a problem.  

Is there any source of these?  Might anyone have it as a spare from a broken elsewhere TAL-M?  Could anyone machine a replacement somehow?  Not expecting a giveaway, more than happy to send a bit your way to help me out!

I would absolutely hate to lose such a fine mount.

Thank you friends

Edited February 15, 2021 by marcelteaching

[marcelteaching]

One though - a threaded rod?  It would fit.  Russians are metric.   

Now, what kind of a head could I put on it?  Is there a way to make it look nice?  A plain threaded rod won't look so great...

Another crazy idea, what if I got it machined back a bit, then rethreaded it?  Would a shortened handle really be noticable?

 

Edited February 15, 2021 by marcelteaching

[DaveL59]

Getting a spare probably won't be easy as these have been out of production for some time, but you may get lucky if someone has a broken mount or can machine one for you.

A threaded rod may well work if you can determine the thread, M4 or M5 perhaps. You could fit a long sleeve to cover the exposed threaded section and fit a nyloc nut to give a shoulder to act against the clamping collar. You could forgo the reduction in the tip for a circlip by using another nut to prevent the rod being unscrewed accidentally.

Getting a suitable knob for the other end, there's probably some available that would screw onto such as:

M2 M2.5 M3 M4 M5 M6 M8 STAINLESS STEEL HIGH KNURLED THUMB NUTS HAND GRIP KNOBS | eBay

or in plastic:
Plastic M4/M5/M6/M8 female thread seven star shaped head clamping nuts knob WY | eBay

Threadlock to keep the knob secure an/or a nut on the rod or both should keep it in place nicely during use.

 

I'd agree too on getting the end re-threaded, should work just find as the knobs are quite long so being 10mm shorter wouldn't be a problem IMHO 🙂 

Edited February 15, 2021 by DaveL59

[Peter Drew]

Pity about the distance to Oz.  I could fix it in less than 15 minutes if down your street.  I would just pop it in the lathe, drill out the remaining bit of thread, re-tap it with the correct thread and screw in a new length with some threadlock.  Surely someone close by in Oz could do this for you?   🙂

[DaveL59]

I've a feeling that the threaded end and shaft is all part of the same piece of metal Peter, from memory. 

Marcel do you have a tap & die set at all? Could be possible to run a tap down the end and then carefully reduce the thread (file it down) and then run the next size down die onto it until you get to the M6 or M5 thread you require. Crude way to do it and a proper machine shop would be able to do it better but if really stuck that might work.

[Dr_Ju_ju]

If you can find the size of the thread (diameter & pitch), then I'm sure one of those industrious chaps north of you (for OZ that is), may well be able to supply something close to what your after e.g. https://www.ebay.co.uk/itm/M8-M10-Steps-Knurled-Thumb-Screws-Aluminium-Handle-Stainless-Steel-Thread-Rod/124161416204  or AliExpress etc....

[DaveL59]

Looking back over old pics I took when I overhauled my TAL-M, reducing the shaft length may work but do measure by how much before heading down that road:

Re-threading the existing one might work but could be very close to hitting the casing at one end of the axis Slo-Mo travel.

[marcelteaching]

Hmm, with the machining a new thread on it, I am worried about the length when I look at it there in the diagram.  The thread is 20mm - so, a corresponding reduction in the handle length would become 20mm also, which could be a problem.  

Another possibility might be to use a m6 thread bar, and attach on a m6 female handle..

Peter - thanks, that was a kind offer.  I wish you were closer.  

[DaveL59]

Perhaps if the existing can be threaded at the existing diameter and a stepped threaded coupler added to screw back into the clamp?

Something like:
Thread Adapter Reducer Nut Clevis Joint Strut Rod End M6 M8 M10 M12 BZP Steel x1 | eBay

Thread-locked onto the shaft it might work... Finding one with a long enough thread may be a problem tho.

Alternatively get the existing screw threaded to M8 and add:

and 

and you would be sorted.

Edited February 15, 2021 by DaveL59

[marcelteaching]

Ah, interesting.

I also found this part: K0179.608X65

But...  the thread is not 20mm - I wonder what effect that would have.  Otherwise - perfect.

[DaveL59]

you could get it threaded further along the shaft but it won't have the shoulder to create a clamping action on the two parts of the collar. A nut fitted onto the thread may solve that tho, so it may be an option if you can get someone to machine a thread further along it, or buy a die and DIY it.

[marcelteaching]

Okay, so this is resolved for now.

I have an m6 threaded rod.  I can shorten that or lengthen it as long as I want.  

I am going to attach that to a nice handle (https://www.oceaniaic.com.au/products/fixed-revolving-and-fold-away-handles/series/i-222/)

Hopefully that will sort it!  A nicer solution would have been to use an m8 version handle, attach a m8 threaded end to attach it, but have it a plain shaft, then reduce it down to a m6 thread somehow, but this will allow me to test the operation of the mount properly, and confirm.  Plus, the $4 part, plus $12 shipping is not bad!  

[DaveL59]

cool, tho I do think you'll need a nut or pair of on the threaded rod in order to pinch the clamping collar. The M6 thread will screw into the far side sure but you need to be pressing the 2 parts together in order to clamp the axle. Below red arrow indicates the side which is threaded, blue arrow the part not threaded. The shoulder on the original presses the unthreaded side toward the threaded (well, draws the threaded toward the unthreaded) such that it pinches the collar and locks the axle. If you fit a pair of suitable nuts on the blue side that'd act against the unthreaded side and get you the required result.

[marcelteaching]

Ah!  That makes sense.  It would be great to have a m8 rod, and then thread both ends m6.  Attach the handle on one end, and this on the other.  

Does anyone know how I can reduce a m8 rod to m6 on it's ends?

[Davey-T]

2 hours ago, marcelteaching said:

Does anyone know how I can reduce a m8 rod to m6 on it's ends?

METRIC THREAD REDUCERS M8 FEMALE TO M6 MALE THREAD REDUCER ADAPTORS HEX 13mm BZP | eBay

[DaveL59]

The problem will be to find a reducer that has a long enough thread to work in this situation. I posted earlier with M8/M6 threaded rod and a coupler that would allow it to be screwed onto an M8 rod. I'd see if I could get the original handle threaded to M8 and then those 2 parts would fot on the end and do what's needed I believe.

Do you have any machining shops around you at all? If not then getting a tap & die set may be an alternative, I seem to use mine quite a bit since I started fettling Binos, scopes and now camera lenses.

[Davey-T]

19 hours ago, DaveL59 said:

Alternatively get the existing screw threaded to M8 and add:

Been hunting round net trying to find a T nut like the one in the picture, bit like a helical thread T nut off a 3D printer but that one looks like an ordinary thread pity they don't actually show one for sale.

Just about to order a bit of brass bar and make one with 8mm thread unless anyone knows where to find one.

Dave

[DaveL59]

I found those on the bay Dave but wasn't looking for that nut as it wouldn't be a lot of use in the TAL-M clutch assembly.

[Davey-T]

On 16/02/2021 at 17:25, DaveL59 said:

I found those on the bay Dave but wasn't looking for that nut as it wouldn't be a lot of use in the TAL-M clutch assembly.

Had a sudden flash of inspiration ( not like me ) realised it didn't need to be round for my purposes so made a rectangular plate out of a bit of brass and soldered a bit of round brass in the middle tapped out to 8mm.

Apologies to Marcel for hijacking his post.

Dave

Edited February 18, 2021 by Davey-T