im not even sure i know what youre saying , but your feed rate and rpm's sound way too high, but someone who knows more will see this and help you.

 

It's not the bits. It's the masonite. That stuff will eat bits for breakfast, so my suggestion would be to use cheap bits you don't mind throwing away or you could try using a diamond hone on the flats of your bit ever so often. You could even send them out to be resharpened.

 

40,000 rpm is a bit fast for any bit. Slow it down to 15,000 and 2 ips.

If you're just making squares and rectangles, why not use a table saw?

 

We have had some issues with the squareness of the boards. We will be mass producing them in the excess of 500+ boards per week with a tolerance of less than 1/32". As you can see a table saw just doesn't do the job when it comes to consistency.

We were looking at Panel saws. I have no experience around them. Are they consistent at making square cuts?

 

Hi Ajd36

I will 2nd the other post,,it comes down to using the right tool for the job.
Table saw is the way to go on this one
The router bit just can't take the heat, you are using a great bit but heat will kill it the hardboard is full of junk,,glue,dirt,rocks, you name it..

If you still want to use your router use a slot cutter bit,it will act the same as a saw blade......
Onsrud 60-239
Upcut 1/4" ,60-239 ,Three Edge Low Helix Spirals router bit.

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Carbide will far outlast HSS for cutting tempered high density fiberboard(hardboard or Masonite for a brand name) but you are dealing with the old paper dulls scissors thing. A slot cutter or saw is a much better choice for this operation.

 

Use a diamond Bit they are $29 at Rona !

 

Ajd36,

With a good TS with a good fence and an aftermarket miter gauge with a long fence and a properly used stop block (or a crosscut sled), all well-aligned and properly set up, a 1/32 tolerance is huge! I must say though that proper setup and alignment, together with well-made equipment to maintain that alignment, is very important but this is true with a router as well.

I love the router but I'm with BJ on this one; a table saw is the best tool for this job. Amongst other things, the blade has a lot more "cooling time" between cuts.