Substituting diamond plate for smooth steel?

[Tinhunter]

Long time lurker but I’ve never joined up to post a question. I’m doing a toter home conversion on an older Kentucky moving van trailer. We’re replacing the king pin plate due to rust damage. It’s a 50” x 102” x1/4” plate.

I had planned on ordering a sheet from our supplier, but 5x10 is a special order size and pretty pricey. However I already have a sheet of 5x10x1/4 diamond plate that’s smooth on the backside.

Any reason I couldn’t use this? The smooth side would be facing down to contact the fifth wheel plate. On the inside it would weld to several crossmembers and the perimeter.

I’ve read that steel DP can be more difficult to weld but never had issues on thinner material. It should also be a little stiffer than the smooth plate. I’d probably have to grind the diamonds off in some areas to get proper fit…Am I missing anything?

[Dale M.]

If you are welding to the "diamond" side I think you are going to have gap issues that will require a lot of filler material to get the welds you want.....

[MAC702]

I think it will work fine if you do the fitment as required. Like you say, it's just stiffer than necessary. I've welded lots of plate and haven't noticed a difference in weldability. I can't think of a good enough reason not to do it if that's what is much more easily available to you.

[Tinhunter]

Thanks for the comments, I appreciate the help!

[shreejisteel]

Using a 5x10x1/4 diamond plate with a smooth backside for your kingpin plate replacement can be a viable option, but there are a few things to consider:

1. Welding Difficulty: As you mentioned, welding diamond plates can be more challenging because of the irregular surface and varying thickness. However, since you've had experience welding thinner diamond plates without issues, you may manage it. Just be prepared for potential difficulties, and make sure you have the right welding equipment and expertise to handle it.
2. Fit and Surface Preparation: Grinding the diamonds off in some areas to ensure a proper fit is a good idea. You want a flat, smooth surface where the kingpin plate will contact the fifth wheel plate. Proper preparation is essential for a secure and safe connection.
3. Structural Integrity: Ensure that the diamond plate is structurally sound for this application. It should be able to support the load and provide the strength and rigidity. Since you mentioned it might be stiffer than the smooth plate, this could be an advantage.
4. Corrosion Resistance: Consider the environment your toter home will be exposed to. Diamond plates may have different corrosion resistance properties compared to smooth steel. If you're in a corrosive environment, you may need to take additional measures to protect it from rust.
5. Weight: Check the weight of the diamond plate compared to the smooth plate. Ensure that it doesn't significantly increase the overall weight of your toter home, which could affect its performance.

In summary, using a diamond plate with a smooth backside is a workable option, but you need to pay attention to welding challenges, surface preparation, structural integrity, corrosion resistance, and weight considerations. If you're comfortable with these factors and believe it meet your requirements, it can be a cost-effective solution for your kingpin plate replacement. However, if you have any doubts or concerns, consulting with a professional or an experienced welder can provide valuable insights and guidance for your project. Good luck with your toter home conversion!