Cross Country Cyclone build

[400brian]

As we are seeing the light at the end of the Spitfire project tunnel, I have begun making plans and assembling parts for the next build.

The first step will be to fabricate another Cross Country clone suspension.

It has really been too hot here to get motivated to be outside. I have been dabbling in a couple of side jobs for the next project. I blew apart an 80 LF skid that is going to get rebuilt. Every shaft in it is seized solid! I got the upper shaft in the front arm cut out by slicing it on each side of the center spacer. I was going to show the grandson how to pull the lower hollow aluminum shaft out one afternoon, but he never saw it happen at 11:00 pm that night. I had moved it by heating and quenching to break the bond, but after several hours of minimal gains I drilled it out to a 1/2" which allowed me to get a hacksaw inside it. I split it multiple different ways but still gained little. I finally took a 3/4" bit and drilled a few inches out of it, which also cleaned the black corrosion out of the tube. I was then able to pound it out in the opposite direction. After cleaning the ID of the tube with a dingleberry hone, I was happy to see no damage inside the tube.

Today I started looking for three rebuildable rear idler wheels between three different parts skids. The first slid off the axle without issue, and I quickly disassembled it. The second was in the center of a skid with both outers missing. Apparently I had given up on it some years ago. I accepted the challenge and went to work on it this evening. After pulling, heating, quenching, on repeat, I gave up and flipped the lever over on the torch and cut the shaft on either side of the wheel. After cutting each side with the angle grinder to get a clean cut, I was able to remove the remains of the tubes. I attempted to press the shaft out of the bearing with no success. There is always another way to skin the cat. So, I drilled the rivets out and disassembled the wheel. I will attempt more heating to remove the steel spacers from the bearing.

[400brian]

So the grandson was out today eager to get some things done. It was slightly cooler here today, but the Canadian wildfire smoke has worked it's way down to southern WI., it is the worst I can remember.

After lunch we started by assembling and riveting together an idler wheel. Heading over to the shop, it seemed the smoke wasn't quite as bad, maybe that was just an optical illusion. The kid wore a mask, I thought the only thing that might have helped would be scuba gear.

The first thing we did was cut the outer race off the idler wheel bearing that was solidly stuck on the piece of shaft I had cut out out of the rear axle. After it was gone, I heated the inner race to just below red hot and quenched it. It was then set aside. We pulled out another Cyclone parts suspension that had two wheels left on it. The puller was threaded into the end a wheel had been taken off of and wound tight. No movement was detected. The two spacer tubes were heated, a bolt was threaded into the side opposite the puller and pounded on...no hint of movement. At that point the lever was flipped over and cutting commenced.

The outer wheel looked like the best candidate, it was put in the vise and the axle was pounded out. We now had the three wheels we needed. Going back to the inner race, it was put in the vise and the axle polished with emery cloth until smooth. A bearing collar was placed on the shaft to absorb the abuse, the assembly put in the vise and the shaft was driven out. Both ends of the shaft had been mushroomed by hitting it, so it had to be dressed down until the race would slide off, but it came.

We then heated the welded-on nuts on the 80 suspension rails that the 1/4" bolts the hyfax retainers use. It was obvious the bolts were going to twist off if we didn't. The fire wrench worked wonders and the little bolts screwed right out and were tossed. Then each rail was put in the vise, the front rail cap was removed, I handed the kid a brass drift and the ballpein hammer and told him to drive the hyfax off. The rails are now ready to go to the welder to get the very egged out shock shaft holes welded shut.

The last thing we had to do was fabricate a model rocket launch stand. We cut a piece of 2 x 10 out of some scrap, matched a piece of steel valley tin to it, grabbed a brazing rod to use as a launch guide, then headed back to the house to assemble it and have pizza. Also while at the house I successfully tapped the steel reducers I wanted out of the inner race.

It was a good day

[400brian]

The reason I am building another CC suspension is that I have a certain amount of parts left over from the 78 LF build, and I feel like I know how to do it now. I also found the ride of the 78 LF with the CC suspension to be a nice upgrade.

I finished the rear idler assembly.

I have purchased a significant number of parts from New Breed, and the 80 rails are at the welder's getting the shock shaft holes which were worn very oblong welded shut.

I have obtained a Trailfire rear suspension arm. If you shorten the legs of the TF arm, it is a dead ringer for the CC rear arm. On the last suspension Brock Weber suggested that I not only run the TF arm, but to install it upside-down. That seemed counter intuitive, but in the end I did it, and if installed with a good gas shock, it seems to give you a little more travel. What it does to the suspension geometry is less clear.

I documented the CC suspension build process in the 78 Liquifire build thread, but in hindsight I didn't provide the measurements of what I actually did. I didn't even write them down for my own future reference. Mainly because I was working out the exact dimensions right down until the very end. I should have measured and noted all that before the final assembly, but I did not. Each suspension build could be slightly different, but my numbers might be used as a guide.

[400brian]

So when it comes to the rear arm for the suspension project, the obvious choice would be the original 80 arm, and on my previous effort that was the direction I was planning to go. But then Brock Weber suggested I might use a modified Trailfire arm for even better results. His claim was that a modified Trailfire arm installed upside down added some travel to the suspension. After using a trailfire arm in my last build, and testing it a bit, I was convinced to do the same on this one.

To use the Trailfire arm in this setup, approximately 2" has to be cut off. The Liquifire arms measure about 8" from the tube to the end, with the bolt holes centered on 7 1/2 " from the tube. Shortening the arms is pretty straight forward, I marked 8" on the top of each outside arm, laid a straight edge across marked the inside two. To make the lines more visible I had first used a white paint pen to paint the arms in the areas to be cut. I then used a square to run the lines down the sides of the arms. With the arm solid in the vise, I cut the arms with a hacksaw.

It is trickier to get the holes in the ends of the arms drilled straight and true. The previous build had shown me this, so I had been thinking about how to improve my accuracy with the tools I had. The arm will not fit in my bench top drill press, so that was out. The first challenge is to get the first hole in an outside arm in the correct position. I measured and used an old vernier caliper to find the center of the arm at 7 1/2 inch from the tube. After center punching it, I drilled a small hole through that outside arm, then used a step drill to take it out to 5/16". The step drill gives you a hole that is more circular than a regular twist drill bit. After confirming that a bolt fit in the hole, the next step is to continue that hole squarely through the adjoining arm. I had found this to be easier said than done previously.

With the target area painted white, I drew a center line down the area. Then I dropped a 5/16" hole transfer punch down the previously drilled hole, keeping the point on the center line, I then used a square to align the drilling point of the second with the first and gave the punch a wack. I had to use twist drills here, but again I started small then finished with 5/16".

I repeated the process on the other side to complete the process. The proof of your work is if you can get a socket on the head and nut of the bolt.
I installed the used washers and plastic sliders between the arms to verify the fit.

[400brian]

To the best of my knowledge, 1978 marks Deere's first use of plastic rear idlers, and they showed up on the 340 Liquifire. Yes, plastic idlers were used on all the bogie sleds since the beginning, but I am talking about wheels with bearings in them used in the slide rail suspensions. The Cross Country suspensions came with aluminum center wheels throughout from the factory, but there was a later recommendation from the factory advising that if you were having problems with the aluminum side idler wheels failing, to try the plastic center wheels. Whether they thought they were more forgiving or they wanted them tested, I don't know.

So if you are cloning a CC suspension, you have to decide what wheels you want to use for aesthetics, or what wheels you have access to.

For the rear idlers you have two basic choices; aluminum or plastic. These are the 7 1/4" diameter wheels that take the 6025 bearing. The aluminum wheels can be disassembled and the bearings replaced. I believe the plastic wheels are available from New Breed.

[400brian]

For the 4" diameter auxiliary wheels that are mounted between the rails in front of the tower, you have three choices I know of;

1) Plastic wheels that are available.

2) The original aluminum center CC wheels ( unobtainium ).

3) The common aluminum center bogie wheels used on all the Deere bogie sleds 74 up.

Generally speaking, the bearing ID needs to be 5/8", but there are outliers. Some cross country suspensions can be found with 17 mm shafts.
The solution is to pay close attention to what you are buying. The plastic and aluminum center bogies typically use a 6202 35 mm OD bearing, but they can be found in either 5/8" or 17 mm ID. In my case, I pitch the 17mm shafts and replace them with 5/8" as 17mm is not commonly available. But no matter what you do, everything needs to match up.

The CC aux wheels use a 6203LLU 40 mm OD bearing that can also be found in 5/8" or 17 mm ID, so be aware of that.

The aluminum center bogie wheels can be disassembled and a new bearing installed. They too use the 6202 35 mm OD bearing with the 5/8" ID. As used as bogies you will find steel bushings in the inner race bringing the ID down to 3/8" for bolting on to the bogie arm.

[400brian]

And then there is the side idlers.

As previously stated, the CC sleds came with 6 3/8" aluminum center idlers mounted outside of the rails at the front arm pivot.

Nowadays these are unicorns. On the previous suspension I built that had CC bones, those had been replaced with plastic wheels. I personally feel that the aluminum center side idlers are what makes a CC sled identifiable, so my personal preference is to have them.

The best option available is 6" Arctic Cat wheels used on 76 Pantera's, at least that is what I have been told, I do not have first hand knowledge of Cat minutia. The problem is that these are obsolete as well, they were just made in greater numbers than the CC side idlers.

Plastic 6" wheels are apparently getting scarce as well, I believe I saw Luke mention at New Breed that he may have the last of them as I write this.

These wheels use the same 6205 bearing as the rear idlers based on what I have seen.

[400brian]

Another consideration is what to use for the various shafts used in the CC skid.

They used far more aluminum in this skid compared to the production suspension. It is hard to know exactly what is correct as the parts book normally doesn't say if a shaft is steel or aluminum, and the racers installed steel in some cases valuing strength over weight reduction.

Starting at the front{

The shaft at the tip of the skid that tied the rails together and had the plastic spools the front springs hooked over was aluminum.

The aux idler wheels between the rails were on steel shafts, with I believe steel spacer tubes.

On the front arm; The 3/4" upper shaft that bolted across the tunnel was steel, and the lower 3/4" shaft was a hollow aluminum tube that allowed the 3/8" tie bolt to pass through.

On the rear arm; the 3/4" shaft that bolted into the tunnel was aluminum. Also, a true CC suspension used an upper idler shaft with two 4' wheels bolted into the tunnel above the rear arm. I assume it was steel, But I have never had one in my hand. On the cloned suspensions, most of the guys seem to go with the 80 LF design and put the two idlers on the rear arm.

The rear idler axle at the very rear of the skid was aluminum. In the photo below I have a steel axle out of a Cyclone at the top, and a reproduction axle Brock supplied. Brock's axle is just a bit over 1/16" longer. In the skid I built that had the CC bones, the axle was steel and I never measured it to see if it was the same as a Cyclone axle, I assume it probably was.

[400brian]

On these CC suspensions, I have been going to the effort of welding 1/4-28 nuts to the tubes so I can add grease zerks.
The welder I have is a very basic Lincoln AC stick unit. I really miss the DC unit I had for years, but I don't weld enough nowadays to even stay in practice. I welded 7 nuts on.

The last item to finish the fab work on the rear arm was to cut out and weld on the upper idler tabs. This Trailfire arm never had idler provisions, but even if it had it wouldn't have mattered as I am installing it upside down. On my previous CC suspension build, I mounted the idler shaft about an inch higher than the stock 80 LF location, which is far lower than the CC idler shaft location. In that example the track fit very snug, so on this one I split the difference and hafe the shaft centerline about 1/2" above the LF position.

The LF tabs are very small 1/8" thick rectangles welded to the arms. In both builds I have opted to go full overkill. The tabs are now welded on and clean up and paint await.

[400brian]

The parts that will identify a CC suspension as you are looking over a pile of junk at a swap meet is right here. When I picked mine up at the Round Up back in 2013, this is what stopped me in my tracks.

A slide rail suspension with aluminum rails, but instead of two plastic idlers at the back ( ala 80s LF ) you see three with these odd spacers in between them! The aluminum teardrop shaped spacers are the dead giveaway.

To convert an 80 suspension into a CC clone, Brock Weber has these parts available.

[400brian]

So with the rails cleaned up and new parts laying on the bench, a test fit seemed appropriate. The 80 bracket is retained with two 1/4" steel rivets, and at the tail end a 3/16 steel rivet. I approached removing these with caution, I assumed the rivets would be corroded into the aluminum tightly.

I ground the heads off the rivets with the angle grinder to start the process. Then I laid the rail across the vice jaws, supporting the area the rivets were in. I made a few test taps with a pin punch and hammer and saw no movement. I then center punched the rivets and slid the rail over onto the drill press and drilled the rivets out to about the depth of the steel bracket. The bracket came off easily, so now the challenge was to remove what was left from the rail. I drilled into the 1/4" rivets with a 3/16 bit about the depth of the rail, then took a tapered punch and knocked them out. I resized the drill bit and did the same to the smaller rivet.

After wire brushing the corrosion off the rail I went to do a test fit of the new brackets. A 1/4" bolt fit looser in the original rivet holes than I would have prefered, and they wouldn't go through the holes in the bracket at all. I weighed my options at that point, eventually deciding to drill the two holes in the steel bracket out to 1/4". With a pair of bolts holding the bracket on in a level configuration, I took a look at the alignment of the small hole at the end of the rail. I wasn't good, so I scribed a mark in the paint of the bracket and removed it from the rail to take a good look.

Drilling the rail to align the hole was out of the question as there isn't any extra material to work with. So I put the bracket in the vise and used a chain saw file to raise the hole up to the line I had scribed. A 3/16" ( number 10 ) bolt fit quite loose in the hole in the rail, so I opted to install a M5 flange head bolt with nut. Paint comes next.

[400brian]

The suspension is starting to come together. I have the idler wheels mounted on the rear arm, and am test fitting various other components. I will give the dimensions of some of these pieces when I get things nailed down.

But the rear arm idler doesn't change when you narrow the skid. I have it mounted higher than stock, but otherwise it is the same. The previous suspension I built used a hollow shaft here, with a long tie bolt through the assembly, here a solid 5/8" shaft was used with a 1" bolt threaded in from each side. The 4" wheels came from New Breed.

[400brian]

Here is the assembly.

[400brian]

In the continuing process of the suspension build, today I power washed the very dirty AC track I have had on hand for years.

Later this evening I slid the suspension into the track for the first test fit. It would no doubt work as I currently have it, but I will tweak it a little yet.

And all of this is happening after the suspension was displayed at the Badger Steam and Gas show.

[400brian]

This 121" x 16" x 2.52 pitch Yokohama track has a few issues in regard to use with a JD suspension.

There two styles of clips used on these tracks. A simple flat clip was used between half the windows, the other half used a clip with a tab that extended up the side of the drive lug, and over the top of it slightly. These cause problems as the Deere drive sprockets will make contact on some of the less than perfectly aligned clips, which will cause rapid wear on the teeth. There are a few ways this can be resolved: 1) Some ignore it. 2) You can take an angle grinder and cut the tabs off, or... 3) Those clips can be removed and replaced with the Deere style clips that have the thrust surface of the clip on the inside of the hyfax.

When I built my first CC clone suspension, I decided I was going to go all out and replace half the clips with the Deere style, and then on top of that, I would narrow the rail spacing to match the Yokohama track. As far as I know, all Deere slide suspension rails have an outside to outside distance, ( measuring at the outside edges of new hyfax ) of 9 1/4". If you measure a number of suspensions, you may find some variance in that measurement, but that is what I have settled on.

To date, I may be the only builder to go to that much effort, but it isn't really all that hard. If you want to use the CC correct 74 - 78 7 1/4" diameter rear idlers, you have to replace the steel rear axle bracket to give the 7 1/4" idlers the correct installed height for the track with clips. A stock 78 rail won't work as it used a square axle as well and a cleated track which raises the inside edge of the track upwards about a 1/4", as the hyfax runs on the cleats witch are attached to the outside surface of the track.