Spindle reinforcement rings are circular brackets cut from plate steel that provide additional mounting strength to your riding lawn mower deck. They strengthen the mounting location where the spindles for the blades are bolted on. If you hit a larger rock, uneven ground surface, or another object with a blade like I did, it can significantly damage the mounting holes. In my case, it ripped the bolt through making it impossible to re-attach the spindle.
If your deck has damage to the mounting holes for the spindles, these rings can save you from replacing your deck.
I had to learn the hard way on this one. The weakest point on my Troy-Bilt Zero Turn lawn mower definitely seems to be the deck. Quick advice, do your due diligence and research as much as you can before making purchases, including riding lawn mowers. This one certainly gave me some buyer’s remorse and a bunch of repair headaches.
First Deck Damage
The first time I had a spindle rip through the mounting holes I wasn’t sure what I was going to do. I talked to a friend of mine who suggested we reinforce the metal. He happens to have a plasma cutter and had some plate steel laying around. It also worked out for me that he keeps a lot of scrap metal around which frequently comes in handy. With his help, we made a cardboard template by tracing out the shape. From their, we traced out a ring onto the plate steel from our template. The next step was to cut it out using the plasma cutter, then weld it into place.
Second Spindle Damage
This one was a chain reaction of events. It started when I mowed over a rock that is mostly in the ground, only sticking out what would seem an inch above the ground. I’ve gone over this rock before without any problems. However, one of the first mowing days of the season when the grass was still fairly tall, I apparently hit it wrong. This forced the spindle to pull threw metal mounting whole of the mowing deck. Perhaps the ground around the rock sank down a bit or had a bit of erosion over the winter.
I assumed I would be calling up my friend again to ask him to help me build another plate ring, but then I found a pre-cut solution…
Ready-Made Spindle Mount Reinforcement Brackets
While looking for a replacement spindle, I found these reinforcement steel plate rings on Amazon that fit my particular mower, this was a 3-pack. You can find reinforcement brackets for other makes and models as well. Just search for your particular make and model on Amazon for “Spindle Reinforcement Ring”. After coming across these, I went ahead and ordered 2 more brackets. I figured it was only a matter of time before I would have damage to the third one. This seemed like a good time for some preventative measures for the third spindle mount.
Two bolts pulled through the mower deck sheet metal (left and right). Notice the cast metal broke off in the upper mount area of the spindle as well. If you’ve had a similar experience where your deck is damaged, you may find you need to hammer some of the sheet metal back down flat again. Or, you may have to even cut or grind some of it away for a reinforcement ring to fit flush.
You can simply have the spindle bolts hold these on, or, like I did, weld them into place. It’s completely optional. Just be careful if welding you don’t burn through what is likely fairly thin metal on the deck. Build up your weld on the spindle reinforcement ring first.
Particularly decks with fairly thin metal. The thicker plate steel makes it nearly impossible for a bolt to rip through the mounting hole like it did on the sheet metal deck.
Hopefully this article helps some of you out there from having to consider buying a new deck for your mower because of spindle damage. Feel free to leave any questions in the comments section below.