I would use 3/4" plywood for the substrate. I don't use chipboard or particle board for ANYTHING.
I would use 3/4" plywood for the substrate. I don't use chipboard or particle board for ANYTHING.
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I build kitchens and buy my Laminate tops from a shop that does countertops. If you bring in your own counter top they charge $45 for cutting a 45 miter and joining the miter. Their miters are always perfect. Not sure what the configuration of you kitchen is but you can purchase laminate in 5 x 12 sheets. You can also buy particle board in the same size so you could end up with no seams
Another thought is keep the 45 and use a tile backspalsh to fill the gap. Easy to do, cheap and adds a lot of visual appeal and some day will add value.
I have used the particle board products from lumber yards and BORGs for years and have never had a problem with it. It is stable. It is cheap. The general grade is consistent enough. Yes, there are better grades of particle board, but for a laminate countertop, you will never be able to tell the difference. It isn't about being cheap. It is about no real benefit of going to the added expense of top quality particle board.
I do not build with particle board in any of my cabinet work, but for countertop substrate it is best product for the job IMHO. Plywood just doesn't compare! There are numerous reasons why particle board is the prefered substrate for countertops.
You can also buy 25" x 12' pieces of particle board. You can form up your countertop with a splice and fasten it together and then laminate the entire thing if you are within the 5' x 12' sheet of laminate. That way you don't have any seams in the laminate. I have made several this way and it works fine. You can then compensate for your bad angle when you make the substrate and your custom laminate will fit like a glove.