1948 KB5 Railway Express


The place to put your K or KB "Build Off" story.

Rusty Driver
Rusty Driver

Posts: 195

Joined: Mon Sep 04, 2017 6:22 pm

Post Mon Nov 23, 2020 10:11 am

Re: 1948 KB5 Railway Express

cornbinder89 wrote:Again, these are very common in medium and heavy trucks. the same system was used in the K series larger trucks.
With heavier trucks, the shoes need to transmit the torque to the backing plate and not the cyl like most lighter brakes do.
My K'7's use the same system. It may be new to you, but foundation brakes are not new or unusual.


---Again, I heard you the first time. My comment about Chevy brakes was stated in humor as these parts are readily available as there were many more manufactured than KB5's and still very popular as opposed to a KB5 or any International truck. It would have been much easier to simply install a contemporary rear axle, front axle, and hydroboost braking system from a late model Freightliner under the truck, but my aim is to do my best to keep this truck as original as possible which is a lot more work, fabrication, and expense.
---I understand what you are calling "foundation brakes," and never heard that term, so must be an old slang for these old brakes. Perhaps with your knowledge you might have expanded on the term for those who also have never heard that term.
---I get the torque from the shoe being transmitted to the backing plate via the adjuster cams/locator pins. I referenced the air brake system as I work in a tractor-trailer shop where we only work on trailers and guess what, the shoes are anchored to the backing plate at one end and the "S-cam" working off the slack adjuster and air chamber is what expands the brake shoes on the non-anchored side. These must be new to you?
---I have seen many styles of brakes and how they attach and work, both auto and big trucks of various ton/class size. Most all are different when comparing year-to-year, manufacturer-to-manufacturer, chassis-to-chassis, and US made-to-foreign. If I knew them all, I'd be god, but yes, many are indeed new to me and that is how I and others learn by digging in and sorting things out.
---If this feature is seemingly irritating you, I can stop adding my updates. I prefer to see a reply a little more positive than, "It may be new to you, but foundation brakes are not new or unusual" because from my end of the computer, I find that statement a little personal and offensive rather than constructive.

Golden Jubilee
Golden Jubilee

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Location: Lyman, IA

Post Mon Nov 23, 2020 1:00 pm

Re: 1948 KB5 Railway Express

mrjim2017 wrote: Perhaps with your knowledge you might have expanded on the term for those who also have never heard that term.
---I get the torque from the shoe being transmitted to the backing plate via the adjuster cams/locator pins. I referenced the air brake system as I work in a tractor-trailer shop where we only work on trailers and guess what, the shoes are anchored to the backing plate at one end and the "S-cam" working off the slack adjuster and air chamber is what expands the brake shoes on the non-anchored side. These must be new to you?

The trailer brakes you describe ARE foundation brakes. The term refers to how the shoes are mounted and transmit the torque to stop the wheel. Working on heavy trucks, I am very surprised you hadn't heard the term, it is in most of the manuals. No, they aren't new to me, as I am a heavy truck mechanic, a CVSA qualified inspector and run my own heavy truck. I also have ASE Master Truck cert.
Most larger trucks use air brakes disk, or either wedge (not common anymore)or S cam but medium trucks are where you will see Hyd drums, and most of what you are thinking is odd-ball is actually common in medium truck hyd brakes. The Hi-torque system is a little different in how it functions, but was common on larger K series hyd braked trucks and was used in some industrial applications until recently. The reason they are different from lighter brakes are the forces involved.
The pins are moveable and removeable so they can be replaced when worn and so the shoe can be positioned in the drum for maximum contact and not have to "wear in" to the drum.
S cam shoes are "cam ground" " thicker at the middle and S cam end then the pivot end, for the same reason. With S cam shoes, there is a lot of lining on the shoe, and the shoes and lining are pre ground to fit before they leave the re liner. Part of that is making sure the cut outs at each end for the pin and rollers are not worn, sometimes you will see repairs made to bring the shoe back to true.
With Hyd brakes there is less lining on the shoe and less total movement of the shoe in the system, for this reason the shoe must be accurately situated in the drum, That is done with the pins, the minor adjustment for wear, just prevents the wheel cyl from retracting all the way when the pedal is released. This keeps the brake-off shoe clearance to a minimum.
There have been verious methods making medium hyd brakes take advantage of dual leading shoes, two single acting cyl, and the Hy-torque system are two of them. They both take advantage of the "self applying feature of the leading shoe make both shoes "leading" in forward direction, where the majority of the braking effort is required. Few truck are driven at high speed backward!

Rusty Driver
Rusty Driver

Posts: 195

Joined: Mon Sep 04, 2017 6:22 pm

Post Sun Dec 20, 2020 1:08 am

Re: 1948 KB5 Railway Express

KB5 REAR BRAKES - FRONT SHOE MODIFICATION

Photo #1 - The factory cast iron shoe is cast wide at the lower base and drilled with a hole that the tip/pin on the brake adjuster/star wheel fits into and is secured. The 3-D scan shows this, but when converted to a 2-D drawing/laser program, this cannot be replicated on the flat steel plate used to make the steel shoes. This needed pin hole has to be added through fabrication.

Machine shop options such as building up with weld and drilling, or creating a steel block, welding it on, then drilling could be options but this means more labor and costs to the shoe. Instead, I fabricated a means to accomplish the same end result. This will get a little confusing in its description, but reading through this and viewing the photos should clarify what I accomplished.

Photo #2 - I found that a 3/8"-16 Grade 5 flange-nut was the right size for the star wheel pin to slip into and the flange on the nut gave a surface that the end of the star wheel could rotate on when making a brake adjustment. The flange nut measured .332" wide or about 5/16", front to flange. I measured 5/16" back on the lower steel plate where the flanged nut needed to be attach, and made a straight line vertically matching the edge line of the steel plate. This line represented how far back I had to notch the steel plate to insert the flange nut. The width of the nut, top to bottom, is approximately 1/2", and I wanted the "flat" side of the nut to set on base of the curved steel plate that the brake lining is riveted to. This aligned the center hole of the flange nut in line with the factory cast hole used to insert the star wheel pin. This left a small amount of steel plate, like a small "leg", that did not need to be cut off. The thickness of this "leg" turned out to be 1/8". So the area at the lower portion of the shoe needed to be notched 1/8" from the top edge of the shoe and back 5/16". I left the 1/8" "leg" portion to act as an alignment pin to hold in place, and locate, the flanged nut by grinding a notch into the flange on the nut to match this "leg." This all sounds confusing, but photo shows the shoe on the right with its unmodified section while the shoe on the left has the notch cut into it. Below the shoes from left to right is the modified flange nut, the unmodified flange nut, and the star wheel with its pin end.

Photo #3 - This shows a better view of the notch ground out in the shoe that the modified flange nut fits into. The flange nut has had the nut, top & bottom, narrowed down to fit between the cut-out section because as is, 1/2" wide, it is too wide. I ground opposing sides down and then ground a slight taper on the lower portion of the nut to fit the angle formed by the curvature of the outer brake shoe plate. This was all done by hand, first grinding with a 4 1/2" grinding disc and finished off with a flat file to fit. The notch in the flange of the nut was cut using a high-speed die grinder and cut-off wheel to match the "leg" that remains in the steel plate of the brake shoe. The flange notch was finished by hand filing and fitted to the "leg."

Photo #4 - The shoe on the right is the factory cast shoe with its casting drilled for the hole that the pin end of the star wheel fits into. The shoe on the left is my adaption using the flange nut. You can see how I cut the notch in the outer edge of flange nut and how it fits onto the "leg" created when grinding the notch in the steel brake shoe plate. The base of the nut has a slight taper so it fits flat on the curved plate. The flange notch and the flat base lock the nut into place as it cannot rotate or move back. The star wheel pin fits into the center of the nut and only pushes against the flange, there is no pulling or side-to-side tension.

Photo #5 - Side view of the star wheel pin set into the flanged nut, and how the flanged nut is positioned into place in the notch in the brake shoe. The pin end of the star wheel protrudes past the width of the nut, so I ground a small clearance scallop in the brake shoe to accommodate the extra length of the pin and finished the scallop by hand filing to fit.

Photo #6 - Was not sure how I wanted to secure the flanged nut into position. I considered JB Weld which I feel would have worked if I didn't have the means to weld, but I decided to braze the nut to the brake shoe. Welding may have worked, but I didn't think I needed to go that route as the nut has no structural properties. Brazing seemed the best choice. With this done, installing the brake linings was my next step.
Attachments
01  Rear Brakes - Front Shoe - Lower.JPG
02  Front Lower Brake Shoe Fab.JPG
03  Front Brake Shoe Fab.JPG
04  Front Brake Shoe Fab.JPG
05  Front Brake Shoe Fab.JPG
06 Brazed Flange Nut.JPG

Rusty Driver
Rusty Driver

Posts: 195

Joined: Mon Sep 04, 2017 6:22 pm

Post Sun Dec 20, 2020 1:16 am

Re: 1948 KB5 Railway Express

Part 1 - KB5 BRAKE LINING ATTACHMENT - JB Marine Weld

I sand blast the curved brake shoe backing that the brake linings gets riveted on to. The factory brake linings measure 3"W x 15"L x 3/8" Thick for use with the 14 1/8" drum diameter. For replacement linings, I purchased a set of NOS Grey-Rock brand #BT12960 linings for a 1956-57 Divco-Twin delivery van. They were 3/4" shorter measuring 3"W x 14 1/4"L x 3/8" Thick. The rivet hole pattern is different than the KB5 pattern, but this was not an issue since I would be drilling new holes for the rivet attachment.

After blasting, I apply a thin & even layer of JB Marine Weld to the brake shoe. I moved the brake linings a little lower than the factory KB5 placement at the top of the brake shoe. The lower section of the brake shoe also ends a little shorter. My reason for the JB Weld was not to bond the linings to the shoes (although this helps), but to compensate as a filler between the lining and shoe to fill in any voids or unevenness that may have been created when the steel plate was shaped/roll formed - but none seemed to exist. I was not intending to turn the drums or turn the brake linings to match the drums, they were being used as is with the brake drums being in very good shape. My thinking was that if clamping the brake shoe/lining to the drum created any distortion or unevenness between the shoe and lining, the JB Weld would act as a filler rather than leave an air gap between them. Any kind of gap between the shoe & lining could have caused the brake lining to crack or break when they were riveted together. The 1947 Wagner Brake Catalog sells shim stock just for this same purpose to compensate for any irregularities in the brake shoe surface.

I C-clamped the brake shoe/lining to the inside of the drum putting a layer of wax paper between the lining and drum. Clamping caused the JB Weld to squeeze out as I had expected. I then let the JB dry for several days. I did this for all 4 brake shoes.

Removing the brake shoe/lining from the drum, I cleaned off the excess JB Weld that had squeezed out. The lining edges had moved a hair when clamping and were just slightly hanging over the steel shoe so I sanded them a little to get them even with the steel shoe edges.

I filed smooth the "tang" end surface of the front shoe that fits into the brake wheel cylinder as it was a little rough. I added a bevel to all the brake shoe holes that are used for spring attachments. The sharp edges could cut into the springs, so adding a bevel and sanding these smooth knocked down the sharp edges.
Attachments
KB5 Clamping Lining - JB Weld.JPG

Rusty Driver
Rusty Driver

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Joined: Mon Sep 04, 2017 6:22 pm

Post Sun Dec 20, 2020 1:21 am

Re: 1948 KB5 Railway Express

PART 2 - BRAKE LINING ATTACHMENT

The next step was to get the brake linings ready for the brass rivets and their installation. I needed to make a fixture that would hold the brake shoe in a "straight up" position where I could move the shoe to drill each rivet hole in the steel plates. A drill press would have been great, or better yet, pay to let someone else do all the drilling might be an option for some, but not me and I had to work with what I had and improvise - backyard mechanic style.

I used a piece of cut 2x4 I had and rounded one end to match the curved shape of the shoe so as to hold it in place. I found the center on the 2x4 and marked a line which was used to line up the brake lining rivet hole making it easier to position my drill bit in line & straight with the mark. I had to bevel the backside edge of the 2x4 so it would clear the stitch welds found on the shoes. By doing this I could then clamp the shoe flat and tight up against the 2x4 to prevent it from moving. The welding clamp worked well to hold it tight and in position. I secured the 2x4 to my table using the C-clamp.

Some of the brake lining holes will get "worms," the JB Weld that squeezes out and through the holes. Some I was able to snap off using a small thick bladed knife I have, but be careful not to damage the rivet hole. If they won't snap off readily, you will need to drill on them to remove them getting them flush with the bottom of the rivet hole. I found that a 1/4 drive 1/4" socket I had fit snug into the brake lining rivet hole. I used this as a guide and a 15/64" drill bit that was inserted down through the socket - you might use a different size, but this is what worked for me. Then holding the socket straight I was able to drill into the JB Weld "worm," stopping when I hit the bottom of the rivet hole. You do not want to drill into or through the rivet hole and oversize it . Anything not drilled out was easily broken free & off with my knife tip.

Next I needed some kind of "guide" to drill straight & centered holes through the brake lining's pre-drilled rivet holes and through the 5/64" thick steel shoe. Using the same technique above, I found that a 4.5mm 1/4" socket I had fit almost perfectly into the pre-drilled rivet hole in the brake lining. The brass rivets used for these shoes requires a 3/16" diameter hole. The socket I had chosen to use had a round drilled hole going through its center, but was smaller than 3/16" (and why I chose it) which was perfect because I then drilled that hole to 3/16" and had my improvised drill guide. To get the socket more snug in the brake lining hole I wrapped one wrap of Scotch tape around its outside and this made the socket a snug and perfect fit into the brake lining hole. The socket acted as my drill guide in getting the drill straight and centered and it protected the brake lining from getting damaged. You can see the socket in the photos positioned in one of the holes of the brake lining and it is lined up with the black guide line on the 2x4 to get my drill bit vertically lined with it.

From that point on, I used my 1/2" electric drill motor and a 3/16" drill bit to drill my rivet holes in the steel plate. My drill has adjustable speeds based on how much you squeeze the trigger. Keeping the rotation slow, which you want to do when drilling steel, I slowly drilled my holes clearing the chips from the socket as they built up. The socket is for a 1/4" drive and the square that the ratchet fits into made a good guide in keeping the drill bit centered by watching that the drill bit was centered within the square drive - this kept the drill bit drilling straight and not off to one side or angled. This was not a fast process so it takes some time to drill each shoe.
Attachments
01 Drill Fixture.JPG
02  Drill Fixture.JPG
Last edited by mrjim2017 on Sun Dec 20, 2020 1:24 am, edited 1 time in total.

Rusty Driver
Rusty Driver

Posts: 195

Joined: Mon Sep 04, 2017 6:22 pm

Post Sun Dec 20, 2020 1:24 am

Re: 1948 KB5 Railway Express

PART 3 - KB5 Rear Brake Lining Riveting

With all the rivet holes drilled, you want to debur all the holes using something like 1/2" drill bit and hand twisting it into the 3/16" holes to remove the jagged edges. Then you are ready to install the brass rivets that hold the linings to the steel shoe.

I purchased a Hand Held Rivet Clincher for 3/16" diameter rivets from Hanson Rivet & Supply, Part #HT-171. I also purchased a bag of 3/16" rivets which come in various lengths, but the correct sizing used by rivet type was a 7-8, 7 representing the 3/16" diameter and 8 represented the length which measured approximately 1/2" long. The use of the correct rivet length should have 1/3 of the rivet length protruding past the drilled hole to get the correct "cinch" on the brass rivet end. I had also purchased a bag of 7-9 rivets in case I needed longer rivets. The 7-8 rivets were what I needed and used.

I set up and clamped a bolt to my work table which was the same diameter as the rivet head and also fit down into the rivet's hole in the brake lining. I installed a rivet into the hole, turned the brake shoe upside down and placed it over the bolt. I balanced the brake shoe on the bolt, gave the shoe a tap to seat the rivet, and then placed the rivet tool on the open end of the brass rivet and hit the tool with a hammer. The hard blows on the tool rolls and flattens the brass rivet end to clamp/hold the brake lining to the steel shoe. Worked real well and went quickly. I did try a 7-9 rivet just to use as a comparison and the 7-9 rivet was indeed too long and did not roll/flatten well. I compared my riveting to the factory riveted brake/lining I have and it looked the same.

With the linings riveted on, and my dirty finger prints washed off, I sand blasted the non-lining side and painted it with a high temperature silver to protect the bare steel. Did this on all the shoes.
Attachments
KB5 7-8 Rivets & Tool.JPG
7-8 Brass Rivets.JPG

Rusty Driver
Rusty Driver

Posts: 195

Joined: Mon Sep 04, 2017 6:22 pm

Post Sun Dec 20, 2020 1:29 am

Re: 1948 KB5 Railway Express

KB5 REAR BRAKE ASSEMBLY

Pic #1 - With the brake shoes lined, I began my assembly of the left rear brake. I sand blasted the brake hardware just enough to clean them up and painted them black. Starting at the top left is the top left (front) brake shoe adjusting cam with its triangle. On the back side you can make out a white "dot". All the adjusters have this mark to identify the high side of the cam lobe, I enhanced it with paint. Below that are the 3 springs used in the assembly. One of the larger two had broken on me and I had to make a new one - these are both the same and originals (the spring I made will go on the right side). The middle column is the break down of the 2 other brake cams, both of which are the same. They bolt through the backing plate. Then the corresponding mounting holes in the brake shoe fits over these cams and the large washer then goes on to hold the shoe in place on the cam and is locked in with the thin/flat horse shoe clip which gets slid into/around the groove cut into the short machined pin on top of the cam lobe. The ends are then squeezed to draw the horse shoe clip closed. You can see the groove in the cam on the right. Note the end of the cam in the middle column, it uses a hex key for adjustment of the cam (which moves the brake shoe in or out against the brake drum) and it has a "dot" identifying the high side of the cam.

Pic #2 - I begin my brake assembly. I started with the front shoe and found that the factory cast iron shoe had a raised & round casting that the brake hold down bolt-to-backing plate went through. The rear brake shoe also has this. In making the flat steel plate shoes, this is not incorporated, but could have been added with welding and machining. The casting has a purpose, as I found out. It makes contact with the backing plate and keeps the brake shoe spaced away from hitting the backing plate as it moves about with the operation of the brakes. I measured the thickness of the casting and found it to be 5/16" in height. I made a spacer of the same thickness using 4 (four) 3/16" x 1 1/4" fender washers stacked together - the same fender washers I used on the Pontiac brake shoe hold down springs used on the back side of the brake backing plate to keep the small head of the pin from pulling through. To make this all work, I first ground a flat in the fender washer I inserted the hold down spring pin through so it would sit flat, and in, the radius of the backing plate. Once passed the pin through the washer and backing plate, I stacked my 4 fender washers onto the pin. I then inserted the spring pin through the hole in the brake shoe and installed my Pontiac hold down springs and hardware. Worked perfectly and the brake shoe was square to the backing plate. I did the same thing for the rear shoe but the rear shoe has an additional locator that is part of the backing plate. It is a flat formed steel tab that inserts into the inside of the brake adjuster and can barely be seen in the photo just below the lower brake spring attachment point on the right. This holds the brake adjuster and brake shoe in alignment and in place.

Pic #3-#4 - Once I had the brake shoes in place on their locating cams, with the front shoe inserted into the wheel cylinder and the brake adjuster arm inserted into the "leg" of the wheel cylinder, I installed the large washers and horse shoe clips. I next installed the brake springs. The star wheel adjuster I had to fabricate and the flange nut I added to the lower section of the front shoe went together as factory. I got all my springs on and everything looked to be good at this point. In the photo you can see the green colored Pontiac hold down brake springs that I used to replace the long thin factory bolts and their double nuts. The fended washers are on the back side of the brake shoe held in place by the hold down spring's pin and are hidden in the pictures.

Pic #5 - I wanted to make sure the brake shoe/lining was in line and square to the brake drum and not excessively tapered due in part to my installation of the fender washers - should I need to remove or add another washer to square the brake shoes up. I made my own tool using 2 small squares I bought at Home Depot. You can see how I put the 2 sliding bodies of the squares together on one scale and clamped the other scale/ruler in alignment with the edge of the square. I then used the machined surface of the axle tube to make my check. I adjusted and slid the scale on the non-axle tube down onto the brake lining while holding the other end flat/square on the axle tube. The brake shoe/lining was indeed squared up with the axle making it squared up with the brake drum - so there should be no big misalignment between the brake lining and inside of the brake drum's surface that it will be stopping against.

This side is now ready for the brake drum and axle installation. The same procedures used to get to this point on the brake installation will be used on the right side.
Attachments
01  KB5 Brake Hardware Parts.jpg
02  KB5 Cast Shoe.JPG
03 KB5 Rear Brake Assembly - Left Side.JPG
04  KB5 Rear Brake Assembly.JPG
05  Checking Squareness of Brake Shoe.JPG
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Golden Jubilee
Golden Jubilee

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Joined: Tue Dec 04, 2012 5:38 pm

Post Mon Dec 21, 2020 10:43 am

Re: 1948 KB5 Railway Express

That looks really good , nice job !

Rusty Driver
Rusty Driver

Posts: 195

Joined: Mon Sep 04, 2017 6:22 pm

Post Thu Jan 28, 2021 9:42 pm

Re: 1948 KB5 Railway Express

This was just placed on a shelf in our parts department for display. Hmmm. Cast iron trailer brake shoes. I thought it interesting and related to the KB5 cast iron rear brake shoes.

Did a little research and found they are manufactured by NeoBrake Systems, Inc.. Appears they were introduced in early 2017 with pricing still to be decided. They are called Matrix NeoCast™. The website states, "The first lightweight cast iron shoe of its kind, combining the traditional advantages of cast iron shoes – lasting rigidity, superior heat dissipation, sustained maximum torque, and optimal lining-to-drum contact – with an advanced, high-carbon ductile cast iron that weighs significantly less than cast shoes of old."

Rick Ballew, NeoBrake president and CEO stated, "When I stumbled upon this high-carbon, ductile cast iron, I knew we had the green light to bring back the only true material for brake shoes and boost drum brake stopping power.”

“Pressed-steel cores were originally developed as one-use products,” shared Ballew. “Ever since there’s been a domino effect on safety and maintenance costs, and this shoe gets the industry back to where it started without the added weight of old cast iron. Which makes even more sense now, with stopping distances being a top priority, because Matrix NeoCast will improve the stopping power of trucks and trailers unaffected by stopping distance mandates.”
Attachments
01  Cast Trailer Brake Shoe.JPG
02  Cast Trailer Brake Shoe.JPG
03  Cast Trailer Brake Shoe.JPG
04  Cast Trailer Brake Shoe.JPG

Rusty Driver
Rusty Driver

Posts: 195

Joined: Mon Sep 04, 2017 6:22 pm

Post Sun Feb 28, 2021 8:04 pm

Re: 1948 KB5 Railway Express

Part 1 - KB5 REAR BRAKE DRUMS

Getting the drums and axles ready for installation. The drums themselves appear to be in good condition. I scooped/wiped out all the old grease that had accumulated inside the drum between the inner and outer wheel bearings. Then I followed this up with a product called "Simply Amazing" which can be purchased at local stores in a spray bottle and refill jug. It is non-toxic and a water clean-up. I use this for cleaning grease off parts as it works great and is cheap. Wiped down the remaining grease and the wheel bearing races.

Pic #1 is the inside of the drum after clean-up. This allowed me to take a close look at the wheel bearing races I had left in the drum. The wheel bearings themselves got washed down for inspection and they looked good and re-useable.

Pic #2 revealed a problem. Closer inspection of the inner bearing race showed light staining in several places. In dragging my fingernail over some of the areas, I could feel it drag, so the staining was also light pitting of the race.

Pic #3 is the outer bearing race, and same thing - staining & pitting.

I did not want to chance putting in the wheel bearings with the pitted races. With the amount of use this truck will ever see, I probably could have gotten away with it. But, since I have it all apart and it is easy to get to at this time, I decided to knock out the wheel bearing races and order new bearings & races. One wheel bearing was an International part, stamped I.H.C. on the bearing. The other was Timken. The races are identical but the inner & outer bearings themselves are different sizes with the outer bearing having a smaller inside diameter. The bearings are rated to support 10,000 pounds. I ordered 2 sets of new Timken wheel bearings & races as I will install a new set on the right side drum as well.
Attachments
01  Inner Drum.JPG
02  Inner Race.JPG
03  Outer Race.JPG
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