Update Time
It's been a few months since this thread was updated. Sorry. For those of you waiting to see/read what's been going on...here's your chance!
Since the last construction entry, the builder decided to include working hand brakes on the logging disconnects. He was making greater use of his 3D printer for various parts. Didn't realize there were so many different types of materials that could be chosen based on application...and that includes a rubber-ish material that was selected to print brake shoes.
One of the first parts needed for the working hand brake was a brake lever fulcrum. Also printed were brake wheels, brake chain drums along with brake wheel ratchets and pawls. The brake design was progressing. Had to print several different versions of the brake shoes to find the best angle for the shoe to engage the wheel tread.
An original idea to use a couple chain links to support the brake beam was thrown out and replaced with a system similar to the brake hangers made for passenger car build threads featured elsewhere in Chaski.
And the end result for the manual brakes...
But wait, there's more. 8 of the 10 logging disconnect trucks (4 pairs) were ready for their outside nature debut. Fighting off the mosquitoes on his home RR, here's a look at the "nearly" completed logging disconnects. Why "nearly"? Well, still need to make the links and pins for the couplers. In fact, sources for 2.5" cast alum scale link/pin couplers seems to have dried up. The guy that was casting these couplers...sold his patterns...but doesn't remember where the patterns went. So,
if anybody knows of 2.5" scale cast alum link/pin couplers...please...shout out! Is there a back up plan? You bet. The builder has been able to program a 3D printed link/pin coupler with a core for resin casting...if it comes down to that.
Anyway, here's a few pix with the logging disconnect on the rail...
Don't believe the builder has put one of these trucks on a scale yet. Safe bet these are in the 50 to 60 pound range for each truck. With most of the weight in the wheel/axle sets that were purchased. Some of the cast iron journals were purchased. But once again, the builder opted to see if he could design/print an acceptable plastic journal. Time will tell how these will hold up to use and abuse.
In addition to the working hand brakes, the trunnion pivots on the bolster and the log chocks are on the trunnion are independently adjustable. The bolster rides on (4) springs,..and this is the only suspension for the truck. The journals are mounted solidly in the side frames. The couplers are sprung and allow for minimal side swing and twist motion.
Will be right back. Carl B.