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Topic: Pullrods and Bellcranks |
Gary Shepherd
From:
Fox, Oklahoma, USA
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Posted 4 Aug 2007 11:28 am |
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What are most pullrods made from? I assume it's some kind of aluminum rod that I could buy at any metal place. And then I'd need a tap to thread the rod and another tap to thread the nylon bushing and nylon ends.
Actually, I prefer the bellcrank system found on Sierra guitars. I have a couple of Carters and the bellcrank/pullrod system is very dependable but it's a PITA to work on. Sierra is much easier to work on and make changes. Of course, the nylong bushing occasionally slip out in the Sierra system.
Anyone got a couple of bellcranks (either Sierra or Carter) laying around?
_________________
Gary Shepherd
Carter D-10 & Peavey Nashville 1000
www.16tracks.com |
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Mike Wheeler
From:
Delaware, Ohio, USA
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Posted 4 Aug 2007 6:20 pm
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Gary, most pull rods today are made out of stainless steel, which is much more temperature stable then aluminum. With the right die, you can thread them yourself with the help of a good vise. I buy this stuff from McMaster-Carr...rod stock, dies, die handles, etc....very fast service.
The nylon hex nuts don't need to be pre-threaded. Their threads will be "cut" as they are screwed onto the threaded rod. Just make sure you get the size that's right for the diameter rod you're using.
If I'm not mistaken, the Sierra and MSA bellcrank styles are similar...a split bellcrank with a round bushing that holds the pull rod by means of a setscrew. Yeah, I love that style! It's the easiest to work with and is extremely smooth and precise.
If your rods slip in the bushings, you might need new setscrews...ones that are designed to bite into the rod.
_________________
Best regards,
Mike |
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Gary Shepherd
From:
Fox, Oklahoma, USA
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Posted 4 Aug 2007 6:24 pm
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Sierra and Carter bellcranks are slightly similar. But the difference is big enough to make Sierra WAY easier to change copedents.
Thanks for the other info.
_________________
Gary Shepherd
Carter D-10 & Peavey Nashville 1000
www.16tracks.com |
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Paul Redmond
From:
Illinois, USA
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Posted 5 Aug 2007 9:59 pm
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Any of the 300-series stainless rod will work well. I prefer 303SS, but use 306SS welding rod available at local welding supply houses everywhere if necessary. If ordering from a steel supplier, be sure to tell them that you want fully-annealed rod. If you don't, your threading die will pay the price.
PRR |
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Mike Wheeler
From:
Delaware, Ohio, USA
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Posted 6 Aug 2007 5:36 am
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Thanks for that tip, Paul.
_________________
Best regards,
Mike |
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ed packard
From:
Show Low AZ
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Posted 7 Aug 2007 6:06 am
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The Sierra cross shafts and bell cranks come in two flavors (old and new). The older cross shafts are round...the Session series (new) are square and a pleasure to work with.
Re nylon slipping out of the bell crank slots...usually only when changing strings (no tension on the finger), or if the adjustment for pedal/lever play is too great.
Check the photos of the BEAST...The use of an e clip, a compression spring, and a grommet will solve the slip out problem, and also allow feeling which rod is being activated at the changer end. |
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Ned McIntosh
From:
New South Wales, Australia
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Posted 23 Apr 2009 4:35 am
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Thanks for the tip about the rods, Paul.
I have a Carter pedal 4 pull-rod for my D10 that I want to shorten so I can use it to add a pull on the 7th string (F#) to raise it (to G/G#, split with a half-stop) via my RKR lever. Shortening it is no problem, but does anyone know what the thread on the end of the Carter pull-rod is? Is it a UNF or something more exotic?
_________________
The steel guitar is a hard mistress. She will obsess you, bemuse and bewitch you. She will dash your hopes on what seems to be whim, only to tease you into renewing the relationship once more so she can do it to you all over again...and yet, if you somehow manage to touch her in that certain magic way, she will yield up a sound which has so much soul, raw emotion and heartfelt depth to it that she will pierce you to the very core of your being. |
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Jerry Bull
From:
Republic, MO, USA
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Posted 23 Apr 2009 9:24 am
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I use a 4-40 die on mine, works good.
_________________
www.psgpicker@gmail.com (Sierra Crown D-10 keyless)2-Nashville 112's, Steelers Choice, Hilton VP, Digitech RP150, Bobro, GeorgeL's cables, BJS Bars and Picks. |
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Ned McIntosh
From:
New South Wales, Australia
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Posted 28 Apr 2009 3:37 am
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My local hobby-shop has 4-40 threaded spring-steel rod so I took my spare Carter pull-rod for a comparison. The Carter thread is much finer in pitch than the 4-40 thread. So, does anyone know what thread it actually is?
If no-one knows, it's not really a problem, I'll just order a RKR pull-rod from Carter when I order some more accessories. Just means I'll have to wait a bit to put that 7th string raise on my E9th neck.
_________________
The steel guitar is a hard mistress. She will obsess you, bemuse and bewitch you. She will dash your hopes on what seems to be whim, only to tease you into renewing the relationship once more so she can do it to you all over again...and yet, if you somehow manage to touch her in that certain magic way, she will yield up a sound which has so much soul, raw emotion and heartfelt depth to it that she will pierce you to the very core of your being. |
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John Fabian
From:
Mesquite, Texas USA * R.I.P.
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Posted 28 Apr 2009 5:04 am
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| The thread is definitely 4-40. |
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Jerry Bull
From:
Republic, MO, USA
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Posted 28 Apr 2009 5:19 am
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I have figured out, it is really easy to get the die started crooked, and if you do the pull rod will appear to be double threaded. so you have to be really careful getting the die started straight.
_________________
www.psgpicker@gmail.com (Sierra Crown D-10 keyless)2-Nashville 112's, Steelers Choice, Hilton VP, Digitech RP150, Bobro, GeorgeL's cables, BJS Bars and Picks. |
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Bent Romnes
From:
London,Ontario, Canada
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Posted 28 Apr 2009 5:49 am
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Also, I recommend using stainless steel set screws. they bite into the 303 ss rod a lot better since the 'cup' doesn't flatten.
Make sure it is 8-32 thread. the set screw with 6-32 thread takes a smaller allen key and strips way easier. |
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Ned McIntosh
From:
New South Wales, Australia
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Posted 28 Apr 2009 12:00 pm
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Thanks John and Jerry, I'll see if I can source a 4-40 button-die in case I need to clean up any threads in future. Looks like my 7th string raise (whole tone, F# to G#) on RKR is go! If I can get the right position on the pull-finger it may even tune with the half-stop to give me a F# to G to G# whilst not affecting the 2nd string lower via the half-stop. No shortage of adjustment on the Carter pull-finger!
_________________
The steel guitar is a hard mistress. She will obsess you, bemuse and bewitch you. She will dash your hopes on what seems to be whim, only to tease you into renewing the relationship once more so she can do it to you all over again...and yet, if you somehow manage to touch her in that certain magic way, she will yield up a sound which has so much soul, raw emotion and heartfelt depth to it that she will pierce you to the very core of your being. |
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Tom Campbell
From:
Houston, Texas, USA
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Posted 28 Apr 2009 12:13 pm
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An easy way to get the die started is to file the end of the rod to a "slight" taper and use a drop of oil on the cutting teeth of the die. I use a "cutting oil" that is made of tap and die work, but regular 'ol oil will do just fine.
Have made many rods. |
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Donny Hinson
From:
Glen Burnie, Md. U.S.A.
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Posted 28 Apr 2009 3:54 pm
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| Quote: |
| What are most pullrods made from? I assume it's some kind of aluminum rod that I could buy at any metal place. |
Aluminum is a poor choice. It expands and contracts far too much with temperature changes. Stainless steel is better, with an expansion/contraction rate about 1/3 that of aluminum. Titanium is even better, with a rate almost 50% less than stainless. However, titanium is expensive and more difficult to thread, and the only company that was using it (MSA on their Millennium) has dropped it as "standard equipment", but still (last I heard, anyway) offers it as an option. |
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Larry Robertson
From:
Denver, Colorado, USA
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Posted 28 Apr 2009 6:07 pm
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Last week I had to redo a pull rod on my MSA Vintage XL. One of the nylon nuts had stripped out. It had been loose enough to turn with my little finger.I ordered the nylon nuts off of Ebay sold by Mike Spaeth from Arkansas They were for 1/8th in. rod. When I tried them on the threaded end of my existing (but failed) rod it just slipped right over the threads. I started measuring rod & threads & discovered that in fact the rod was 1/8th in. (.125) but the threads were smaller. They also did not match a 4-40 die. It slipped right over also. I looked up a thread chart on the 'net somewhere and discovered that the 4-40 thread outside diameter is smaller than .125. That means the nylon nuts meant for 1/8 in rod will slip if the nuts are threaded before installation. I simply turned the rod around, used the other end, cut the 4-40 threads and threaded the nylon nut onto the rod. It is tight and will not slip for a long time. PS: The thread chart listed a 5-40 thread that I had never heard of that had an outside diameter of threads as .125. I thought this would be the thread originaly on the rod, but never could find a 5-40 die. And John Fabian says they were 4-40 anyway, so maybe someone had previously re-threaded the rod improperly.
_________________
Website: www.Music2myEars.net
MSA D-10, Carter U12, Fessy SDU-12,Emmons P/P D-10, Emmons P/P U-12,Emmons S-10 ShoBud SuperPro, Lap steel, keyboards, 6-string Guitars.. too many |
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ed packard
From:
Show Low AZ
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Posted 28 Apr 2009 6:13 pm too hot to handle
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Ned M...your footnote says a lot!
Rod metals...choose for workability, availability, and environmental tolerance re rust/corosian etc.
The wound strings usually have SS cores of various diameters with wraps of different materials of various dimensions.
The plain strings are usually of SS.The strings may have different string length to scale length ratios, or may have similar string length to scale length ratios (as in keyless/gearless).
The key issue is detuning with temperature change (and some force induced distortions in the mechanisms, usually lumped as "cabinet drop/body flex").
The SS plain and cored strings grow in length as the temp rises.The body and/or frame also grows in length as the temp rises...different wood at different rates, aluminum at another, carbon fibre at supposedly very little, none, or even a bit negative.
The rods also grow in length as the temp rises; the rods may be anything from a couple of inches to about as long as the body.And then there are the pedal stops and associated rods...a number of different lengths and values here that are temp sensitive to various degrees.Throw in the finger materials and geometrics.
So we have things changing in all kinds of ways and in different amounts with temperature. No two designs, or even different setups of the same design giving the same dimensional results.
The basic test would seem to be how many cents change per degree of temp change, and on which strings (they won't all change the same amount/rate).
PSG makers are not going to tell you this...is it possible that they do not know what their product does? I would suggest that the rod material is of secondary or less importance re thermal considerations.
Finer threads will give finer tuning capability.
RE the SIERRA type nylon slipping out of the bell crank slot...this can happen when changing some strings if the nylon has been placed in the wrong slot in the bell crank. I use retainer springs on mine. |
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John Fabian
From:
Mesquite, Texas USA * R.I.P.
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Posted 29 Apr 2009 2:17 am
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| Larry Robertson wrote: |
| Last week I had to redo a pull rod on my MSA Vintage XL. One of the nylon nuts had stripped out. It had been loose enough to turn with my little finger.I ordered the nylon nuts off of Ebay sold by Mike Spaeth from Arkansas They were for 1/8th in. rod. When I tried them on the threaded end of my existing (but failed) rod it just slipped right over the threads. I started measuring rod & threads & discovered that in fact the rod was 1/8th in. (.125) but the threads were smaller. They also did not match a 4-40 die. It slipped right over also. I looked up a thread chart on the 'net somewhere and discovered that the 4-40 thread outside diameter is smaller than .125. That means the nylon nuts meant for 1/8 in rod will slip if the nuts are threaded before installation. I simply turned the rod around, used the other end, cut the 4-40 threads and threaded the nylon nut onto the rod. It is tight and will not slip for a long time. PS: The thread chart listed a 5-40 thread that I had never heard of that had an outside diameter of threads as .125. I thought this would be the thread originaly on the rod, but never could find a 5-40 die. And John Fabian says they were 4-40 anyway, so maybe someone had previously re-threaded the rod improperly. |
MSA pull rods were threaded at 5-40. Carter threads are 4-40. |
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Larry Robertson
From:
Denver, Colorado, USA
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Posted 29 Apr 2009 5:02 pm
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Hey, Thanks John. I suspected that 5-40 was the original MSA thread. BTW: I love my Red Carter U12. Thanks to you & Bud for building a great guitar.
_________________
Website: www.Music2myEars.net
MSA D-10, Carter U12, Fessy SDU-12,Emmons P/P D-10, Emmons P/P U-12,Emmons S-10 ShoBud SuperPro, Lap steel, keyboards, 6-string Guitars.. too many |
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John Polstra
From:
Lopez Island, WA, USA
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Posted 2 May 2009 4:28 pm
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| Larry Robertson wrote: |
| PS: The thread chart listed a 5-40 thread that I had never heard of that had an outside diameter of threads as .125. I thought this would be the thread originaly on the rod, but never could find a 5-40 die. |
Larry, you can buy 5-40 dies from McMaster-Carr.
John |
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