JD 5 sickle mower restoration

[Oldgreenpaint]

So I bought a JD-5 mower and overall it isn’t in terrible condition. Working through the machine and mostly blasting and painting. Wear plates all needed replacing and found most of what I needed at Cutting Components in NE. Made my own new pitman arm. Some of the guard ledger plates are worn quite a bit, and I was able to find old stock JD plates that are similar, but not a perfect match. New ones are beveled, much like a serrated knife section. I decided to try drilling out the plate side of the single rivet. This worked OK and I was able to pry out the old ledger plate.

Looking at the guard bottom, I cannot see the other end of the rivet at all. I am assuming that it does penetrate bottom of guard and perhaps peened into a corresponding countersink, but I do not know this. I am looking to learn from anyone that has changed ledger plates. What is best method to remove rest of rivet shank? I could through drill it, but will likely not follow the old rivet very well. I tried a punch and hammer and it didnt seem to move at all. Of course, it is 80 years old and well rusted by now. Anyone have tips to share?

New and old plate, top side

New and old plate, bottom side

Drilled top side of rivet, plate pried out. Shank of rivet is embedded

Bottom side of rock guard shows no hint of a rivet.

 

[DanielW]

They do poke through. As you suspected, into a little countersunk divot. After years of rubbing along the ground it'll be worn smooth and even so you can't see it. You should be able to punch/press it out, but I'll bet it's pretty rusted in there. It may be best to drill through the centre with a pilot bit to try and relieve some of the pressure, or maybe add some heat.

Make sure the new one fits tight, make sure there's no loose rust/debris on the mating surfaces, make sure the semi-circle locating tab fits snug, and make sure you clamp the ledger down somehow as you rivet. Just like with sections on a knife, if it's not clamped tight (or if rust/junk works its way out from between the mating surfaces) it'll feel tight at first, but vibrate lose very soon.

Were you able to find the proper countersunk rivets? A few years ago TSC still sold them - they probably still do. You need to support a good hefty punch on an anvil or bottomed out in a vice to hold the head on the ledger side while you hammer from the bottom. JD used to sell a specual punch with a groove for that purpose, but you can use any large punch (I used to use a drawbolt with a flat end). And make sure you rivet properly: Smack straight down for the first few whacks to expand the rivet body, then peen the head over. Lots of folks only peen the head over without expanding the body of the rivet first, and that just isn't good enough. One advantage of rivets over bolts (even today with new sickle knives) is that when installed properly, the rivets are hit/swaged so that the body expands and they fill the entire cavity and have some residual compressive stresses, so there's no ability for vibration/movement/fatigue. Bolted knives have serrated shanks to try and accomplish the same thing but they don't offer nearly as much contact area in the bore as a rivet does.

You mentioned you made a new pitman. Did you get the centre-to-centre distance between ball socket and pin the correct length? If not correct, the knife will be out of register and won't cut worth a dang. Not a big deal: You can adjust the register on the knife, so chances are your pitman will work dandy as long as you check/adjust the register. That's a step that a lot of people overlook with sickle mowers, and it's one of the primary reasons so many people have difficulty with them plugging and end up dumping them in a fence row.

 

[wore out]

They do poke through. As you suspected, into a little countersunk divot. After years of rubbing along the ground it'll be worn smooth and even so you can't see it. You should be able to punch/press it out, but I'll bet it's pretty rusted in there. It may be best to drill through the centre with a pilot bit to try and relieve some of the pressure, or maybe add some heat.

Make sure the new one fits tight, make sure there's no loose rust/debris on the mating surfaces, make sure the semi-circle locating tab fits snug, and make sure you clamp the ledger down somehow as you rivet. Just like with sections on a knife, if it's not clamped tight (or if rust/junk works its way out from between the mating surfaces) it'll feel tight at first, but vibrate lose very soon.

Were you able to find the proper countersunk rivets? A few years ago TSC still sold them - they probably still do. You need to support a good hefty punch on an anvil or bottomed out in a vice to hold the head on the ledger side while you hammer from the bottom. JD used to sell a specual punch with a groove for that purpose, but you can use any large punch (I used to use a drawbolt with a flat end). And make sure you rivet properly: Smack straight down for the first few whacks to expand the rivet body, then peen the head over. Lots of folks only peen the head over without expanding the body of the rivet first, and that just isn't good enough. One advantage of rivets over bolts (even today with new sickle knives) is that when installed properly, the rivets are hit/swaged so that the body expands and they fill the entire cavity and have some residual compressive stresses, so there's no ability for vibration/movement/fatigue. Bolted knives have serrated shanks to try and accomplish the same thing but they don't offer nearly as much contact area in the bore as a rivet does.

You mentioned you made a new pitman. Did you get the centre-to-centre distance between ball socket and pin the correct length? If not correct, the knife will be out of register and won't cut worth a dang. Not a big deal: You can adjust the register on the knife, so chances are your pitman will work dandy as long as you check/adjust the register. That's a step that a lot of people overlook with sickle mowers, and it's one of the primary reasons so many people have difficulty with them plugging and end up dumping them in a fence row.

X 2 on the need to be SURE the knife is "in register'.

 

[Oldgreenpaint]

They do poke through. As you suspected, into a little countersunk divot. After years of rubbing along the ground it'll be worn smooth and even so you can't see it. You should be able to punch/press it out, but I'll bet it's pretty rusted in there. It may be best to drill through the centre with a pilot bit to try and relieve some of the pressure, or maybe add some heat.

Make sure the new one fits tight, make sure there's no loose rust/debris on the mating surfaces, make sure the semi-circle locating tab fits snug, and make sure you clamp the ledger down somehow as you rivet. Just like with sections on a knife, if it's not clamped tight (or if rust/junk works its way out from between the mating surfaces) it'll feel tight at first, but vibrate lose very soon.

Were you able to find the proper countersunk rivets? A few years ago TSC still sold them - they probably still do. You need to support a good hefty punch on an anvil or bottomed out in a vice to hold the head on the ledger side while you hammer from the bottom. JD used to sell a specual punch with a groove for that purpose, but you can use any large punch (I used to use a drawbolt with a flat end). And make sure you rivet properly: Smack straight down for the first few whacks to expand the rivet body, then peen the head over. Lots of folks only peen the head over without expanding the body of the rivet first, and that just isn't good enough. One advantage of rivets over bolts (even today with new sickle knives) is that when installed properly, the rivets are hit/swaged so that the body expands and they fill the entire cavity and have some residual compressive stresses, so there's no ability for vibration/movement/fatigue. Bolted knives have serrated shanks to try and accomplish the same thing but they don't offer nearly as much contact area in the bore as a rivet does.

You mentioned you made a new pitman. Did you get the centre-to-centre distance between ball socket and pin the correct length? If not correct, the knife will be out of register and won't cut worth a dang. Not a big deal: You can adjust the register on the knife, so chances are your pitman will work dandy as long as you check/adjust the register. That's a step that a lot of people overlook with sickle mowers, and it's one of the primary reasons so many people have difficulty with them plugging and end up dumping them in a fence row.

Dan,
That is some really good info. I built two aluminum airplanes, so I understand well how rivets are such good fasteners. I wish I had understood the ledger plate stuff before I had cleaned and painted all the guards!
I have not sourced the rivets yet. I need to work on that. Do you happen to know diameter and length? I will try a Search using the JD part number and see if anything pops up.
I was fortunate that the old pitman was still intact, and I just duplicated it, actually using the old part as a pattern and drilling through it into new oak wood. I’m a carpenter so that op went well. Checking register is still on my list. Just starting to put everything back together now.
Finding a new tire was one of the most difficult tasks. I don’t think they are currently in production. I was able to find one after quite a search.

 

[ET]

You should be able to get the rivets through JD.

 

[bob p mn]

I spent alot of years around JD sickle mowers started with a #4 horse mower we pulled behind our 8N & the n moved up to a #5 mower, Daniel is right I always drilled all the way through the rivet & then took a punch & drove the remaining rivet out. never had to heat one, would then set the guard on the horn of an anvil to set the new rivet, took a little time but not that bad of a job. Used to buy the rivets right from Deere but the last ones I got all came in misc boxes of stuff at auctions.

 

[Destroked 450]

I think my brother still has dads tool he got with his #5 for replacing ledger plates and sections

 

[Oldgreenpaint]

You should be able to get the rivets through JD.

Just for fun, I stopped by local JD dealer and checked on the rivets. The parts guy said they are ‘Obsolete’. But, he was able to check remaining stock availability and found a box of 29 of them 100 miles away. JD Parts network is really good. They deliver daily, so the delivery truck picked them up and brought them to local dealer. Cost…..$3.01. Told the nice young lady that was the cheapest thing I ever bought at a JD store. Told her the box was probably way older than she was.

other interesting thing is that the diameter of shank is .201” I was expecting them to be .187. So using a 13/64” drill will get me about .001” shank clearance.