1948 KB5 Railway Express


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

Site Admin
Site Admin

Posts: 4913

Joined: Thu Nov 29, 2012 9:10 am

Location: Nampa, Idaho

Post Sun Aug 16, 2020 6:25 pm

Re: 1948 KB5 Railway Express

Look good, hope they work the first time.

Golden Jubilee
Golden Jubilee

Posts: 340

Joined: Sun Nov 15, 2015 8:16 am

Post Sun Sep 06, 2020 4:11 pm

Re: 1948 KB5 Railway Express

I enjoyed reading your very descriptive blog in this forum. A ton of fine, detailed work and may I say great, great patience.

BK

Golden Jubilee
Golden Jubilee

Posts: 8283

Joined: Thu Dec 27, 2012 12:45 pm

Location: Canada's left Coast

Post Sun Sep 06, 2020 6:04 pm

Re: 1948 KB5 Railway Express

FANTASTIC !!!
I would rather have tools I do not need than to need tools I do not have
“Never argue with stupid people, they will drag you down to their level and then beat you with experience.
Mark Twain

Yard Art
Yard Art

Posts: 92

Joined: Mon Sep 04, 2017 6:22 pm

Post Sun Oct 11, 2020 9:33 pm

Re: 1948 KB5 Railway Express

Thanks for the support. I have not gotten around to the rear brake install as the heat & humidity was kinda high here in NC and couple that with hungry mosquitoes, I just stayed away from working on the truck.

I am back tackling the rear brakes as it has now cooled. I placed the steel shoes up into place just to see if they were going to fit or if I was going to have to make modifications. Amazingly,the fit like originals.

So I began to remove the adjusting cams that the brake shoes set on and are used for brake shoe adjustment. I had a problem with the top front cam which has a "triangle" plate that rotates and sets into a flat notch on the brake shoe. See No. 16 in the illustrated brake drawing. Not sure why it is designed this way. Anyway, on the back side is the 15/16" nut that tightens it to the backing plate and it was frozen solid. Used a little heat and hit it with PB Blaster and did this a couple times with no movement. My standard 6-point socket was too short to get a good bite on the nut and I did not want to get crazy putting a ton of pressure on the breaker bar and round off the nut. I needed a deepwell socket which a guy at work had. The nut sat a week with the PB Blaster coating it and I went out today and slipped the deepwell socket on and this time used more force on the nut and it broke free. It was raining here all weekend, so I returned into my house knowing I can remove the adjusted another day.

The original cast iron shoes are held into place on the backing plate by a long fine thread bolt which passes through an oversized hole in the shoe. See No.'s 6,7,8,9 in the illustrated brake drawing. Each side of the shoe is raised about 1/2" where this bolt passes through and can be seen in the drawing. The replacement steel shoes are of course flat. I did not like the double nutted bolt idea and decided to use a little more contemporary set-up. I was able to use the hold down pin, springs, and hat from a 1960'-70's Pontiac drum brake - Photo 1. I had a kit hanging around and tried it and it fit. You will see the pin which first passes through a large fender washer and then passes in from the back of the backing plate. The pin then passes through my steel brake shoe hole. The Pontiac brake shoe has a "hat" with a flared end that sets down into a sized hole on the shoe and is seen in the photo, but the hole in the KB shoes is much bigger so I got a washer that the flared end of the hat fits into and then sets over the shoe's hold down hole. This actually allows side movement of the spring in the same manner the factory bolt has side movement through the oversized hole. Then the green spring fits into the hat and over the pin. Then the green spring is compressed to install the top hat that locks everything together - just like the drum brakes on an older car. I purchased another set for the other side when I get to it.

Next up was the replacement of a broken brake shoe spring. If you look at the brake illustration, the broken spring is No. 4. Working at a big rig trailer shop, I was able to match up a brake spring that looked close, but had different ends. The trailer spring also has a slightly larger wire diameter and is a slight bit shorter in the coil winds - but I think it'll work OK as the tension both pulling and bending the spring seemed to me about the same. I rigged up a piece of small round steel bar I had and clamped it to a vice. I then heated the end hooks with my torch, putting pressure on the hook with pliers to get my bends. I heated the wire just enough to get it into a state of "soft plastic" and formed the end hooks around my steel bar to get the shape I needed. Then I cut the excess from the formed hooks off with my die grinder and cut-of wheel. Pic 2 shows the factory spring at the top, the middle spring is what I made, and the bottom spring is what I started with.
Attachments
KB5 Hi-Tork Rear Brake Assembly.JPG
DSCN0397.JPG
DSCN0398.JPG
Previous

Return to K and KB Build-Off

Who is online

Users browsing this forum: No registered users and 1 guest

cron
Powered by phpBB® Forum Software © phpBB Group
Designed by ST Software for PTF.