The Forestry Forum

General Forestry => Sawmills and Milling => Topic started by: Cazzhrdwd on April 30, 2016, 10:22:49 AM

Title: Split Rail Locust Posts
Post by: Cazzhrdwd on April 30, 2016, 10:22:49 AM
I have a job where I'm cutting some large locust post and making split rail posts out of them. Problem is the holes have to be 4 inch by 6 inch which means a very large difficult hole to cut. I've done them in the past with a chain saw but would like to do a more professional job. I was thinking either a Forstner bit or a hole saw but was wondering if you guys had any suggestions.

I'm thinking either bit is going to be very difficult to do with a hand held drill and the post will be very heavy to put up on a drill press?

The posts will be 4x8 and 9ft long, with 5 holes.
Title: Re: Split Rail Locust Posts
Post by: simonlow on April 30, 2016, 11:20:10 AM
Hello, maybee an old mortiser (mortise machine) and bench/jig would do the job.Does it need to be a mobile operation?
Title: Re: Split Rail Locust Posts
Post by: WV Sawmiller on April 30, 2016, 01:01:14 PM
Cazz,

   Better hope they are green locust posts. I thought I'd start a friction fire sawing dry locust posts one time last year.

   Don't know if you could cut side by side holes 4" apart and 6" above each other with a big auger bit (maybe 1" or so) with another pair at the top and bottom of the marked off hole location then connect the cutouts using a chainssaw or reciprocating saw as shown below. That's what I would try. Good luck.

                                      O
                                    O  O

                                    O  O
                                      O
Title: Re: Split Rail Locust Posts
Post by: Cazzhrdwd on April 30, 2016, 02:27:34 PM
I could use a smaller bit, it would certainly get it done.

Simonlow its not a portable job, I'm not sure where to get one of those.

Anyone ever use a bit that big?
Title: Re: Split Rail Locust Posts
Post by: scully on April 30, 2016, 07:56:53 PM
Don't even use a hole saw ,you will be very unhappy . There is a self cleaning forstner bit that would work well . as for the side cuts I am an artist with a chain saw
Title: Re: Split Rail Locust Posts
Post by: Kbeitz on April 30, 2016, 08:11:55 PM
I was at a wood tool machinery store in Williamsport pa and seen a tool that I bet would do your job.
I never seen anything like it before. It was a table mounted mini chainsaw blade that was only about
one inch wide and 12-14" deep. It would do a plunge cut right down into the wood. it looked really old.
I wish I would have taken a picture of it. I was thinking that maybe it was used to make the large square
tenons in barn beams. The companys name was Hermance. Maybe you could give thema call.

866-326-8131
Title: Re: Split Rail Locust Posts
Post by: Cazzhrdwd on April 30, 2016, 08:59:53 PM
Don't even use a hole saw ,you will be very unhappy . There is a self cleaning forstner bit that would work well . as for the side cuts I am an artist with a chain saw

With such a large bit, do you think I can hold on to it.
Title: Re: Split Rail Locust Posts
Post by: Cazzhrdwd on April 30, 2016, 09:01:04 PM
I was at a wood tool machinery store in Williamsport pa and seen a tool that I bet would do your job.
I never seen anything like it before. It was a table mounted mini chainsaw blade that was only about
one inch wide and 12-14" deep. It would do a plunge cut right down into the wood. it looked really old.
I wish I would have taken a picture of it. I was thinking that maybe it was used to make the large square
tenons in barn beams. The companys name was Hermance. Maybe you could give thema call.

866-326-8131

I'm familiar with Hermance but I need to keep this under budget.

Thanks though, I'll check it out, sounds interesting.
Title: Re: Split Rail Locust Posts
Post by: Larry on April 30, 2016, 09:51:54 PM
Don't even use a hole saw ,you will be very unhappy . There is a self cleaning forstner bit that would work well . as for the side cuts I am an artist with a chain saw

I'm also interested if you can provide a link or name for that bit.  I have a friend that has been talking to me about doing the same thing on fence posts and so far I haven't come up with a timely method.

I have an old Powermatic chain mortiser that might work.  Trouble with them standard blades and chains are $400 a set.  It would have to be extra big to do a post and I would hate to even ask for a quote for the blade.

I'm thinking a custom machine that uses a standard chainsaw making a plunge cut.
Title: Re: Split Rail Locust Posts
Post by: Kbeitz on May 01, 2016, 06:49:02 AM
So thats what they are called...."Chain Mortiser"

Here is the one I was talking about...

 

 (http://www.forestryforum.com/gallery/albums/userpics/39553/Chain_Mortiser.jpg)
Title: Re: Split Rail Locust Posts
Post by: Dave Shepard on May 01, 2016, 09:47:19 AM
For a hole that size, I think a timber framers mortiser signs be one of the fastest ways to do this. Not remotely cheap, however. Why are the holes so big? Typically they are three two inch holes with the webs cut out of the middle. This would be fast with a hole hawg and a mortise axe.
Title: Re: Split Rail Locust Posts
Post by: Cazzhrdwd on May 01, 2016, 03:33:21 PM
For a hole that size, I think a timber framers mortiser signs be one of the fastest ways to do this. Not remotely cheap, however. Why are the holes so big? Typically they are three two inch holes with the webs cut out of the middle. This would be fast with a hole hawg and a mortise axe.

It's a custom application for horse jumping. I don't think I'll be able to hold on to a 4" bit so I'm going to try a 3" Forstner and chainsaw the side cuts. The problem with this (hole) thing is going to be the hardness of Black locust. I've been reading that the Forstner bits aren't very sharp.
Title: Re: Split Rail Locust Posts
Post by: WV Sawmiller on May 01, 2016, 06:46:00 PM
I've been reading that the Forstner bits aren't very sharp.

  I got a 1.5" Forstner bit with my Tenon cutter set and it is slow going in green buckeye which is about the softest wood out there. I'd certainly check out a ships auger bit as they are longer and cut faster. Then just connect the dots with your chainsaw or wood chisel.
Title: Re: Split Rail Locust Posts
Post by: just_sawing on May 01, 2016, 07:02:18 PM
We have split 15000 rails since last April and I pass on cutting the large holes. The big boys use a dedicated machine that is more than I am wanting to do. People are seeing my sick rail fences and doing them instead. 

 (http://www.forestryforum.com/gallery/albums/userpics/13282/0706151716a.jpg)
Title: Re: Split Rail Locust Posts
Post by: WV Sawmiller on May 02, 2016, 08:07:44 AM
    I guess the process would largely be determined by how many posts you are cutting. If sufficient number I think I'd square 2 sides (sounds like you already plan to do that as mentioned a 4"X8"X9' post). I'd make a template first with cardboard then cut it out of a thin wider board or heavy plastic, mark the posts with a sharpie or such then use an auger on a drill press to cut the corners (You did not mention if the holes are oval or square - I first assumed oval but could be square and probably easier) then cut out the plug/mortise with a small chainsaw or a reciprocating saw.

   For the brace posts (corners and gates) I'd think you'd need to start with 10" post squared to an 8X8 (maybe with a little rough corners left on all 4 sides).

   If just a handful I'd just use a hand drill and chainsaw.