[j.t. 4579]

what router bit do I need to cut the cove in dutch shiplap?

 

[Semipro]

Hello and welcome to the router forum
First these bits can be a little costly
Here is the kind bit you are looking for, and needs be done on a router table
Freud 3-1/2" (Dia.) Raised Panel Bit with 1/2" Shank (99-518)

 

[j.t. 4579]

I'm a little late in life to have been bitten by the wood bug, but here I am. I am going to replace a lot of the shiplap
on my house and I figured I would just make it rather than buy it. I have most of the tools to do it. I'm just not well
versed on router bits. I thank you for the info.

 

[old55]

Welcome to the forum.

 

[Semipro]

FYI you can not cut that big a cove in one pass run your lumber in at least two passes I would prefer go three

 

[TWheels]

@j.t. 4579 you have an ambitious undertaking. I do think it is more economical for you to pursue your chosen course. The Freud bit mentioned by @Semipro is the closest profile I can find. This bit is available on Amazon at about 80% the price I could find anywhere else.It is a monster bit so it needs to be run at reduced speed and as @Semipro says run several,passes.

 

[TenGees]

That doesn't seem like a job for a cordless router. Those are big bits, usually used in a router table.

 

[sreilly]

A bit that size isn't intended or shoudl be used in any handheld router. At 1-1/2" diameter it should also run no faster then 16,000 rpm. This is a job for at least a 2 HP router or larger mounted in a router table and take multiple passes to make that cut. This is not much different then a raised panel cutter.

 

[DesertRatTom]

Router table with at least a 2 1/4hp router Multiple passes--my limit is 1/8 th inch per pass.
The thin lip needs to fit under the rabbet. It is really a matter of the total width of each piece as to how big the diameter needs to be. Perhaps you could pass the lip through a table saw to reduce the amount you want to remove. The red line in the illustration shows where to make the table saw cut.

I would also prefer to cut the rabbet on the other edge on a table saw with a dado stack buried in a sacrificial fence. Depending on how many feet of this you're cutting, this will save a lot of wear and tear on your expensive cove bit.

Looks to me to be about 3/8ths deep on both lip and rabbet, if that's 3/4 stock. In ffact, you could use the table saw with dado stack to cut the coved side to the correct thickness, preferably after you make the diagonal cut. That will be that much less to take off with the cove bit, which might allow you to use a smaller cove bit. I would not do ALL of this on a router since a table saw assist is MUCH faster.

 

[j.t. 4579]

Thank you guys for all this info, I would have never thought of these short cuts. I have access to a large router with
1/2" shank, I have the bosch portable table saw and I watched a video about cutting the rabbit with a dado. I have been
known to bite off more than I can chew sometimes. It will probably be a little trial and error with me on this but I
just want to thank you guys on this forum for the help.