I don't know what to call these knobs, but they are failing at a frequent rate. The knob shown in the first picture below is the knob that is used to tighten and loosen the internal section of the prism pole (raising and lowering the rod height). The internal brass piece has an knurled surface which fails where it meets the plastic material. The torque needed to sufficiently tighten the clamping mechanism exceeds the failure torque of the knob as designed.
I called Sokkia (the maker of the prism pole) to see if I could get a replacement knob, and they told me that individual parts are not available for this prism pole, and that my choices were 1) to figure out how to fix it myself, or 2) buy a new rod for $200-300. I'd like to fix it.
This failure has occurred with other clamps as well, including data collector pole clamps (2nd picture below).
Has anyone else been having these problems, and if so, what have you done to repair them?
Thanks,
Al
Yea stop over-tightening the stuff. :p
Maybe try Seco rods instead? I've actually had a problem where the rubber grip around the knob got loose over time and would slide around it instead of tightening it. I never had the problem you've experienced, but I only ever had one Sokkia pole.
Reinstall the knob -- shimming with Teflon tape if necessary -- then drill both knob and shaft for a press-fit roll pin.
I would call Hayes Instruments, I had to replace a knob with the build in level and clamp, they said they have alot of older and used rods in the back, if they the one I needed they would ship it to me, also they gave me a great price.
Dan Patterson, post: 388827, member: 1179 wrote: Yea stop over-tightening the stuff. :p
Maybe try Seco rods instead? I've actually had a problem where the rubber grip around the knob got loose over time and would slide around it instead of tightening it. I never had the problem you've experienced, but I only ever had one Sokkia pole.
Dan,
I think the problem that you have had is the same one I'm having - the rubber grip slides around the internal brass machine part. I've had the exact same problem with SECO parts as well - it is not limited to Sokkia.
I agree that overtightening can lead to this problem - but I don't think I'm overtightening - when I back off on the torque, the internal section of the pole still moves.....
Thanks,
Al
Jim Frame, post: 388831, member: 10 wrote: Reinstall the knob -- shimming with Teflon tape if necessary -- then drill both knob and shaft for a press-fit roll pin.
Yes, that would work. I like it.
In my experience, every prim pole made, other than the brass ring compression with a metal level vial, is garbage. I have yet to see a quick release pole worth buying.
Big Al, post: 388839, member: 837 wrote: Yes, that would work. I like it.
Who did you talk to at Sokkia? Can you tell me what pole you have and how long you have had it? I'm not saying I can get the part you need but I might be able to find someone that has one available.
pmoran, post: 388863, member: 8922 wrote: Who did you talk to at Sokkia? Can you tell me what pole you have and how long you have had it? I'm not saying I can get the part you need but I might be able to find someone that has one available.
Hey Pat,
Thanks for the help.
I believe it was Vanessa that called from Topcon/Sokkia in Livermore, CA. I have the 727069 pole. She told me that this pole had been discontinued and was replaced by 727070. My pole was shipped directly from Sokkia on 12/16/2011. I was looking on SECO's website, and the twist lock mechanism on Sokkia's pole seems very similar, if not identical, to SECO's TLV. The outside diameter of the outer section of the pole is approximately 1.25". The attached diagram from SECO indicates that the part that I need may be:
No. 5, D10525, KNOB,SMALL,W/STUD,5LOBE,1",TL
Also, one other thing. Someone else at Sokkia indicated that Sokkia does not ship parts to end users, but rather that end users need to work with their dealer. In this case, I purchased the prism pole from Stakemill (John Gay), and I have been in touch with them as well for assistance.
Al
Perhaps a two-part epoxy might bond the plastic to the metal. I agree that a mechanical device like a roll pin or key would give you a distinct advantage moving forward.
Big Al, post: 388869, member: 837 wrote: Hey Pat,
Thanks for the help.
I believe it was Vanessa that called from Topcon/Sokkia in Livermore, CA. I have the 727069 pole. She told me that this pole had been discontinued and was replaced by 727070. My pole was shipped directly from Sokkia on 12/16/2011. I was looking on SECO's website, and the twist lock mechanism on Sokkia's pole seems very similar, if not identical, to SECO's TLV. The outside diameter of the outer section of the pole is approximately 1.25". The attached diagram from SECO indicates that the part that I need may be:
No. 5, D10525, KNOB,SMALL,W/STUD,5LOBE,1",TL
Also, one other thing. Someone else at Sokkia indicated that Sokkia does not ship parts to end users, but rather that end users need to work with their dealer. In this case, I purchased the prism pole from Stakemill (John Gay), and I have been in touch with them as well for assistance.
Al
Hi Al,
We don't sell or really do anything directly with the end user except for support. Our dealer network does the service and sales end of it and we support them. I don't have an old catalog but judging from the color scheme I'm guessing its an SRX pole?
That looks like a SECO D11016 "KNOB,SMALL,5LOBE W/HOLE-THRU,1/4-20" to me.
If you contact SECO, I would think it would be under warranty.
Or any SECO dealer should be able to sell you one for $3.16 (plus shipping most likely.)
pmoran, post: 388881, member: 8922 wrote: Hi Al,
We don't sell or really do anything directly with the end user except for support. Our dealer network does the service and sales end of it and we support them. I don't have an old catalog but judging from the color scheme I'm guessing its an SRX pole?
Pat,
Yes, it is an SRX pole. I have the RC-PR3 remote controller, and I believe the pole is designed to fit the RC-PR3
Al
[USER=703]@Tommy Young[/USER]
I agree, have purchased prism poles with four different type of height adjustments thru the years and have not actually been satisfied with any of them.
Something is flawed on everyone of them.
This stuff is being made by a handful of companies that are contractors who build and sell to products to the suppliers.
The rods with the toggle switch to raise and lower the prism has lasted longer for me.
Try http://www.leevalley.com/us/hardware/page.aspx?p=61657&cat=3,43576,61995&ap=1 . Lee Valley markets, among other things, bits and pieces woodworkers need to make jigs.
Thanks for all the help, everybody!
Have you tried your local hardware store? I've been able to replace knobs and other parts at my local hardware store. And the ones I couldn't find in stock I could size using the in store templates. Once you what you want, you can find almost anything on the internet.
http://www.ebay.com/sch/i.html?_from=R40&_trksid=p2047675.m570.l1313.TR0.TRC0.H0.TRS3&_nkw=knob+thru+1%2F4-20+sz&_sacat=0
huge selection, buy a handful or two
I prefer the type with a conventional hex nut inside
A Harris, post: 388890, member: 81 wrote: [USER=703]@Tommy Young[/USER]
I agree, have purchased prism poles with four different type of height adjustments thru the years and have not actually been satisfied with any of them.
Something is flawed on everyone of them.
This stuff is being made by a handful of companies that are contractors who build and sell to products to the suppliers.
The rods with the toggle switch to raise and lower the prism has lasted longer for me.
I have said it here before, so at the expense of sounding like a Leica rep (not, nor have I ever been one), Leica poles will apparently last a long time, place I worked 1990-95 had harsh conditions and harsh crews and never broke or needed a repair to a Leica pole in those five years and the poles were NOT new when I showed up in 1990. Went on my own in 1995, still have my original GLS11 Leica pole and never been taken apart or needed service and still have one of three tripods I bought new in 1995 (one was stolen and I fell against another on a steep fill slope last summer and snapped a leg off, BUT kept the digital level upright as I banged my body up, LOL). Leica definitely builds better accessories from what I have seen vs SECO and Topcon, Sokkia, etc.
SHG