3 Attachment(s)
Horseman FA "rise lock knob" replacement.
After 15 years without a serious mishap, my beloved Horseman FA and tripod blew over on a gusty day in Escalante, UT, this past autumn.
Two components were damaged: the swing plate, and the "rise lock knob".
I was able to order the parts from Kenko Professional Imaging in Japan.
The swing plate replacement went well, but the "rise lock knob" has me baffled.
The rise lock knob is a captive thumb-screw that requires a tiny c-clip on one end to provide captivity. The problem: there is no room to insert the c-clip.
It appears one must somehow remove the threaded insert (embedded nut) from the front standard, then install/screw-in the shift lock knob into the threaded insert and attach the c-clip, then screw-in the entire tiny assembly back into the front standard. Finally it seems there must be some type of glue to hold the threaded insert into place, as there's no visible set screw (that I can see)--there would be no point of having a captive screw if the entire tiny assembly can loosen and fall out.
Does anyone have experience replacing this knob or something similar to this knob?
Three photos:
Attachment 131023
Attachment 131024
Attachment 131025
Regards,
Doug
Re: Horseman FA "rise lock knob" replacement.
I don't have my FA in front of me to see, but to ask the obvious, the knob is screwed in as far as it will go and still the e-clip won't go on?
Re: Horseman FA "rise lock knob" replacement.
Quote:
Originally Posted by
ic-racer
I don't have my FA in front of me to see, but to ask the obvious, the knob is screwed in as far as it will go and still the e-clip won't go on?
Yes, the thumb-screw is screwed-in all the way. BTW, having your FA in front of you may (?) not be useful because this c-clip area is usually hidden from view when the front standard is installed on the camera.
I'll further add that there are no slots in threaded insert to accommodate using straight screw driver to aid in removing the insert (from the outer-side of the assembly (thumb-screw side)).
I've made a tool using a 3mm screw and 3 tiny washers: the 3 washers have their outer diameters filed-down so they'll fit into the recessed hole and they're stacked onto the screw, then the screw is screwed-in in a reverse direction to remove the insert. I'm afraid to tighten the screw too much for fear of stripping the threads. I've also applied heat (boiling water) to heat the area while attempting to remove the insert, and still no luck.
Re: Horseman FA "rise lock knob" replacement.
Just to check that the thumb screw is a single piece (probably is). Any know function for the threaded insert? If not, you could grind it out with a Dremel to get the e-clip on.
Re: Horseman FA "rise lock knob" replacement.
Quote:
Originally Posted by
ic-racer
Just to check that the thumb screw is a single piece (probably is). Any know function for the threaded insert? If not, you could grind it out with a Dremel to get the e-clip on.
The thumb screw is a single 3mm screw with a thumb head on one end, a c-clip groove in the other end.
As a last resort I have considered countersinking the c-clip cavity (with dremel or drill). I haven't decided...I might opt to send it out for repair instead of countersinking, as countersinking does weaken the structure (tho probably not critically) and it's not as pretty of a solution.
I've also flooded the insert with acetone hoping it would soften any glue or thread-lock material, and then applied my extraction tool (described above)... still no luck.
I'm also waiting to hear back from Kenko, as I've posed the question to them weeks ago, but I'm not optimistic they will reply.
Re: Horseman FA "rise lock knob" replacement.
I just realized that enlarging the hole in the c-clip area isn't a good idea because it houses a little rubber flat plug that resides between the rise-lock-screw's end and the surface that it pushes against (the standard that can be raised).
One could enlarge the hole to get the c-clip in, then fill with glue, but that's kinda ugly.
Re: Horseman FA "rise lock knob" replacement.
A tiny circlip would go straight on the shaft, rather than slide-on perpendicular to the shaft.
3 Attachment(s)
Re: Horseman FA "rise lock knob" replacement.
I found the trick to removing the insert, it just took more heat than that of boiling water.
I put the assembly on a stove burner while applying my home made extraction tool, and the threaded insert became removable. It seems there's a glue Horseman used that takes high temps to remove. Regular hot-glue can generally be removed with the temperature of boiling water.
Pictures follow:
Front standard after the insert was removed.
Attachment 131757
The tiny parts and home made extraction tool.
Attachment 131758
The final assembly ready to be reinserted into the standard with a new application of hot glue.
Attachment 131759
Finally I used a laser-pointer, target (with center hole), and cut glass for the film holder and lens board, to re-align/adjust those surfaces to be parallel.
Thanks ic-racer for keeping the thread alive.
Re: Horseman FA "rise lock knob" replacement.
Quote:
Originally Posted by
Doug Sprock
I found the trick to removing the insert, it just took more heat than that of boiling water.
I put the assembly on a stove burner while applying my home made extraction tool, and the threaded insert became removable. It seems there's a glue Horseman used that takes high temps to remove. Regular hot-glue can generally be removed with the temperature of boiling water.
Pictures follow:
Front standard after the insert was removed.
Attachment 131757
The tiny parts and home made extraction tool.
Attachment 131758
The final assembly ready to be reinserted into the standard with a new application of hot glue.
Attachment 131759
Finally I used a laser-pointer, target (with center hole), and cut glass for the film holder and lens board, to re-align/adjust those surfaces to be parallel.
Thanks ic-racer for keeping the thread alive.
Thank you for a great tutorial. I own a few Horsemen and this is invaluable information. Wonderful cameras!
Re: Horseman FA "rise lock knob" replacement.
Thanks for posting. Solves my confusion...I thought the threaded insert came out the other side, thus I wasn't sure how removing it would help getting the e-clip on. Thanks for positing.
More Horseman repair info here also: http://www.largeformatphotography.in...epair&p=841777