Sept 6th, 1966....
-G
-G
CK5
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'72 K5 - Greg's @MightAsWellK5 Build
- Thread starter Greg72
- Start date
This is the build description. I will improve this later. (GB)
why did I think you were younger?
you are only4 months younger than me.
Bring a walker for me Greg, I'm a year older than you FFS. 
You old fart...Bring a walker for me Greg, I'm a year older than you FFS.
I will not be needing a walker anytime soon.
maybe when I am 90
2014.06.30 - UPDATE! - BURNING THROUGH SOME G-NOTES.....
I spent some time dealing with a few smaller items this weekend.
First on the agenda was finally getting my 7075-T6 Aluminum Links spec'ed out and ordered from Branik. I've been emailing back and forth with Stan and trying to get all the little details sorted out to make sure everything is perfect with no disappointments when all those expensive parts finally arrive here.
As part of the discussion, Stan assured me that there's no reason to worry about using aluminum for the PHB, even though it has a bend in it.
So I traced out the link on my workbench and pulled dimensions from it...
Ultimately, I'm going to have Branik build me a total of 10 links:
Tie Rod
Drag Link
Front Upper Link
Panhard Bar
Front Lower Links (x2)
Rear Upper Links (x2)
Rear Lower Links (x2)
That should easily burn through a G-note, and probably half of a second one as well.
I figure at this point I'm "close enough" to the end of the suspension design/test work to have them built in their final materials (and diameters) and this will allow me to install them and check one final time for any interferences while I still have time to cut and modify brackets. A few of these links are going to be quite a bit larger in diameter than the mock-up links were, so there's a chance that something that used to have adequate clearance, suddenly may NOT anymore!
While I am waiting for the links to be machined and shipped out, there were a few lingering things that I was able to mess around with yesterday.
First was to make a few small changes to the PS steering arm. The uppermost plate needed to be clearanced for the draglink heim so that the threads would not hit the plate under droop. I reduced the radius of the curve at the end of that plate by about 1/4", so the result still looks nice but now clears in all conditions. The other thing I did was to bore a through-hole in the middle plate so that the thick-walled spud could be lengthened to pass through both plates (as a single tube, instead of 2 separate ones). You can see the basic idea here before I reinstalled it on the PS arm.
You may also remember that I had on objective to use the factory Unimog 404 steering arm on the PS as a way to reinforce the lower part of my new steering arm design. As it turned out the original hole for the draglink ended up INSANELY close to where my lower plate ended up..... sheer coincidence, but it was a great bit of luck!
The original tapered hole was just slightly off the mark, so my 5/8-11 - 8" through-bolt would not actually drop through it and allow me to secure the nut onto it. So I welded up the hole and marked it in the correct location and drilled a clean, new 5/8" hole there.
Here's the shot of the welded up arm, just before drilling.
Finally, since I had a bit of time remaining.... (and I'd already done the research and ordered up a couple of bearings) I started on the upper idler pivot....
The bearings have a 3/4" I.D. and the O.D. is reaalllly close to the same dimension as a scrap of 2" x .120" wall DOM that I had laying around. So I spent some time with a few sanding rolls and gently opened up the ID of that tube until the outer race started to drop down in there snugly.
I'll drop a second scrap of 1.75" x .120 wall DOM inside to act as a backstop for the bearing races (on both sides). My target is to have the overall width (including the installed bearings) at 2.25" wide. This will match the width of the heims that are also being installed on that steering idler, so it should keep things nice and uniform.
That's about it for now. My guess is that the links won't be here until after the 4th of July break, but once those are installed the truck should be safely able to bear it's own weight, and I might just be tempted to charge up the ORIs with some nitrogen and take some "outdoor" photos....
-G
I spent some time dealing with a few smaller items this weekend.
First on the agenda was finally getting my 7075-T6 Aluminum Links spec'ed out and ordered from Branik. I've been emailing back and forth with Stan and trying to get all the little details sorted out to make sure everything is perfect with no disappointments when all those expensive parts finally arrive here.
As part of the discussion, Stan assured me that there's no reason to worry about using aluminum for the PHB, even though it has a bend in it.
So I traced out the link on my workbench and pulled dimensions from it...
Ultimately, I'm going to have Branik build me a total of 10 links:
Tie Rod
Drag Link
Front Upper Link
Panhard Bar
Front Lower Links (x2)
Rear Upper Links (x2)
Rear Lower Links (x2)
That should easily burn through a G-note, and probably half of a second one as well.
I figure at this point I'm "close enough" to the end of the suspension design/test work to have them built in their final materials (and diameters) and this will allow me to install them and check one final time for any interferences while I still have time to cut and modify brackets. A few of these links are going to be quite a bit larger in diameter than the mock-up links were, so there's a chance that something that used to have adequate clearance, suddenly may NOT anymore!
While I am waiting for the links to be machined and shipped out, there were a few lingering things that I was able to mess around with yesterday.
First was to make a few small changes to the PS steering arm. The uppermost plate needed to be clearanced for the draglink heim so that the threads would not hit the plate under droop. I reduced the radius of the curve at the end of that plate by about 1/4", so the result still looks nice but now clears in all conditions. The other thing I did was to bore a through-hole in the middle plate so that the thick-walled spud could be lengthened to pass through both plates (as a single tube, instead of 2 separate ones). You can see the basic idea here before I reinstalled it on the PS arm.
You may also remember that I had on objective to use the factory Unimog 404 steering arm on the PS as a way to reinforce the lower part of my new steering arm design. As it turned out the original hole for the draglink ended up INSANELY close to where my lower plate ended up..... sheer coincidence, but it was a great bit of luck!
The original tapered hole was just slightly off the mark, so my 5/8-11 - 8" through-bolt would not actually drop through it and allow me to secure the nut onto it. So I welded up the hole and marked it in the correct location and drilled a clean, new 5/8" hole there.
Here's the shot of the welded up arm, just before drilling.
Finally, since I had a bit of time remaining.... (and I'd already done the research and ordered up a couple of bearings) I started on the upper idler pivot....
The bearings have a 3/4" I.D. and the O.D. is reaalllly close to the same dimension as a scrap of 2" x .120" wall DOM that I had laying around. So I spent some time with a few sanding rolls and gently opened up the ID of that tube until the outer race started to drop down in there snugly.
I'll drop a second scrap of 1.75" x .120 wall DOM inside to act as a backstop for the bearing races (on both sides). My target is to have the overall width (including the installed bearings) at 2.25" wide. This will match the width of the heims that are also being installed on that steering idler, so it should keep things nice and uniform.
That's about it for now. My guess is that the links won't be here until after the 4th of July break, but once those are installed the truck should be safely able to bear it's own weight, and I might just be tempted to charge up the ORIs with some nitrogen and take some "outdoor" photos....
-G
y5mgisi
1 ton status
great fun!
Wooohoo!!! Outdoor shots!
Big step man very cool can't wait to see em
Nom-nom, I like cereal.
Waiting for outdoor shots before I give ya any more " prouds". Btw.
Waiting for outdoor shots before I give ya any more " prouds". Btw.
Nom-nom, I like cereal.
Waiting for outdoor shots before I give ya any more " prouds". Btw.
That's your happy birthday update.
Maybe I should have sent YOU a Hurrycane?
-G
Saw this on FB and thought of you.
Except yours is more awesomer!
I think they even described the clearance as "buckets of clearance"
Except yours is more awesomer!
I think they even described the clearance as "buckets of clearance"
Well, I've finalized my link order and sent off the final specs to Branik for production... should have everything here in a little over 1 week. 
In the meantime, I have been struggling with the last details of the steering system as you can see here:
Here's the back story:
During the time when I was working to resolve my Ackerman steering (or lack thereof)....I disconnected the small draglink (idler) from the rest of the system. This allowed me to hit the steering stops on the knuckles without worrying about bottoming-out on the steering box stops or other interferences.
Since my new WFO steering arm arrived, I decided to drop it into position and start taking some measurements to see where the through-hole should be drilled so that I can get full-steering in both directions (against the knuckle stops). Things began to get weird....
First, I swung the steering against the steering stops (knuckles) on each side and then measured to the existing pitman arm hole (also swinging the pitman to it's internal stops in the same steering direction each time) and the dimensions for hard left turns vs hard right turns were off by more than 2 inches!!!!!! On a hard left turn, the required length for my small idler draglink would be something like 14.875" for a full-right turn, but only 12.125" for a full-left turn!!!
As I'm sure most people would do..... I decided that the problem was that the pitman arm must not be "indexed" properly on the steering shaft... and since the WFO arm doesn't have any of those solid keyways to force me to install it a particular way, I could rotate it by one spline at a time until those two lengths were identical..... right?
WRONG.
Turns out, all you accomplish by moving the index is changing both numbers to some other value, but you really don't get them any closer to each other.
What DOES work, is changing the relationship between the idler pivot length and the hole spacing of the pitman arm itself......
Originally, I set the idler spacing at 5.5" (top hole where it pivots at the frame) down to the hole where the small upper draglink attaches to it. This value was selected because that is also the hole spacing of my original pitman arm (5.5"). My logic was that since the numbers were identical, the motion of the pitman arm would translate EXACTLY as motion of the idler arm..... In reality, this does not happen. I'm still at a bit of a loss to understand why, but I suspect it has to do with the fact that the pitman arm is travelling in an arc that is different from the arc that the idler arm travels... so the relationship is NOT linear at all.
I started screwing around with the relationship between those hole spacings, increasing the idler.... decreasing the pitman and taking measurements at full-left and full-right turns. Sure enough..... the distance between those holes became more similar to each other. At first, they were almost 2.75" different, but with a bit of trial-and-error I had a combination that got them to around 1/8" different!!! Not bad.
What I learned is that for my particular setup, the ratio of idler to pitman are is around 0.795:1 so if I want a pitman arm to be spaced at 5.17", I need to make sure my idler has hole spacing of 6.50" to make it all work.
Strange stuff.....
-G
In the meantime, I have been struggling with the last details of the steering system as you can see here:
Here's the back story:
During the time when I was working to resolve my Ackerman steering (or lack thereof)....I disconnected the small draglink (idler) from the rest of the system. This allowed me to hit the steering stops on the knuckles without worrying about bottoming-out on the steering box stops or other interferences.
Since my new WFO steering arm arrived, I decided to drop it into position and start taking some measurements to see where the through-hole should be drilled so that I can get full-steering in both directions (against the knuckle stops). Things began to get weird....
First, I swung the steering against the steering stops (knuckles) on each side and then measured to the existing pitman arm hole (also swinging the pitman to it's internal stops in the same steering direction each time) and the dimensions for hard left turns vs hard right turns were off by more than 2 inches!!!!!! On a hard left turn, the required length for my small idler draglink would be something like 14.875" for a full-right turn, but only 12.125" for a full-left turn!!!
As I'm sure most people would do..... I decided that the problem was that the pitman arm must not be "indexed" properly on the steering shaft... and since the WFO arm doesn't have any of those solid keyways to force me to install it a particular way, I could rotate it by one spline at a time until those two lengths were identical..... right?
WRONG.
Turns out, all you accomplish by moving the index is changing both numbers to some other value, but you really don't get them any closer to each other.
What DOES work, is changing the relationship between the idler pivot length and the hole spacing of the pitman arm itself......
Originally, I set the idler spacing at 5.5" (top hole where it pivots at the frame) down to the hole where the small upper draglink attaches to it. This value was selected because that is also the hole spacing of my original pitman arm (5.5"). My logic was that since the numbers were identical, the motion of the pitman arm would translate EXACTLY as motion of the idler arm..... In reality, this does not happen. I'm still at a bit of a loss to understand why, but I suspect it has to do with the fact that the pitman arm is travelling in an arc that is different from the arc that the idler arm travels... so the relationship is NOT linear at all.
I started screwing around with the relationship between those hole spacings, increasing the idler.... decreasing the pitman and taking measurements at full-left and full-right turns. Sure enough..... the distance between those holes became more similar to each other. At first, they were almost 2.75" different, but with a bit of trial-and-error I had a combination that got them to around 1/8" different!!! Not bad.
What I learned is that for my particular setup, the ratio of idler to pitman are is around 0.795:1 so if I want a pitman arm to be spaced at 5.17", I need to make sure my idler has hole spacing of 6.50" to make it all work.
Strange stuff.....
-G
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You could say you went off on a "tangent" pun intended 
I always thought the idler has to be the same length to keep those numbers good.
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So did I.....
My plan was really simple: Try to keep the dimensions uniform for as many parts as possible so that I didn't create a bunch of weird motion-ratios in the steering linkage.
- My steering arms on the axle have a hole spacing of 8.75" each (from the upper kingpin centerline)
- My original pitman arm had hole spacing of 5.50"
When I built the idler pivot, I made sure the top hole was also at 5.50" spacing (to match the pitman arm it connected to)..... and then the lower hole (The crossover draglink) was at 8.75" to match the hole spacing of the steering arms that it connected to.
Seemed to be logical....... 5.5" pitman pushes the idler on a 5.5" pivot point, which then translates that motion to a larger 8.75" pivot on the idler.... which ultimately moves the 8.75" steering knuckles.
The motion ratio of the idler is either:
8.75 / 5.50 = 1.59 : 1
or
5.50 / 8.75 = 0.6285 : 1
Depending on which way you apply the numbers. No matter what, they don't match the ratio between the pitman arm and the upper idler hole that I just figured out last night ( 0.7954 : 1)
I think it's related to the non-linearity of the arcs that everything is traveling in, but someone a lot smarter than me is going to have to explain that part.
-G
y5mgisi
1 ton status
Oh ok.So did I.....
My plan was really simple: Try to keep the dimensions uniform for as many parts as possible so that I didn't create a bunch of weird motion-ratios in the steering linkage.
- My steering arms on the axle have a hole spacing of 8.75" each (from the upper kingpin centerline)
- My original pitman arm had hole spacing of 5.50"
When I built the idler pivot, I made sure the top hole was also at 5.50" spacing (to match the pitman arm it connected to)..... and then the lower hole (The crossover draglink) was at 8.75" to match the hole spacing of the steering arms that it connected to.
Seemed to be logical....... 5.5" pitman pushes the idler on a 5.5" pivot point, which then translates that motion to a larger 8.75" pivot on the idler.... which ultimately moves the 8.75" steering knuckles.
The motion ratio of the idler is either:
8.75 / 5.50 = 1.59 : 1
or
5.50 / 8.75 = 0.6285 : 1
Depending on which way you apply the numbers. No matter what, they don't match the ratio between the pitman arm and the upper idler hole that I just figured out last night ( 0.7954 : 1)
I think it's related to the non-linearity of the arcs that everything is traveling in, but someone a lot smarter than me is going to have to explain that part.
-G
So the pitman arm and the steering arm are different length and it's a big difference.
I know you want the pitman arm to be shorter to give you more steering range but maybe that's too much.
Are you needing all that travel?
The arc of the pitman and idler are in different planes, so things don't move with the same ratio.
'72 K5 - Greg's "Might As Well™... BURNING THROUGH SOME G-NOTES...!!!!
Yup I was going to do the math, but without the correct angles it's hard so I stopped
Yup I was going to do the math, but without the correct angles it's hard so I stopped
bp71k5
3/4 ton status
'72 K5 - Greg's "Might As Well™... BURNING THROUGH SOME G-NOTES...!!!!
I wonder if part of the problem is also that the pivot point on the small "pivot arm" (is that called the idler arm in the picture?) isn't directly above the bolt for the heim on the draglink. Assuming the picture shows everything in the "centered" position, if you draw an imaginary line from the center of the two bolts in your picture, you can see that as the assembly rotates clockwise, the heim end starts moving almost completely horizontally, and just a tiny bit downward. But as the end of the heim moves counterclockwise, the end of the link starts moving upward as well as horizontal as it follows the arc. This is why the horizontal motion being transferred to the tie-rod isn't the same for both directions. If a similar motion difference is at the pitman arm, it could exaggerate the problem even more. Not sure if that makes any sense without a diagram.
I wonder if part of the problem is also that the pivot point on the small "pivot arm" (is that called the idler arm in the picture?) isn't directly above the bolt for the heim on the draglink. Assuming the picture shows everything in the "centered" position, if you draw an imaginary line from the center of the two bolts in your picture, you can see that as the assembly rotates clockwise, the heim end starts moving almost completely horizontally, and just a tiny bit downward. But as the end of the heim moves counterclockwise, the end of the link starts moving upward as well as horizontal as it follows the arc. This is why the horizontal motion being transferred to the tie-rod isn't the same for both directions. If a similar motion difference is at the pitman arm, it could exaggerate the problem even more. Not sure if that makes any sense without a diagram.
