Thin Kerf Glue Line Rip Blades

tomp · Post by **tomp** » Fri Feb 15, 2013 11:26 am

Has anyone used these blades? I am thinking of trying a Freud 10x30 Thin Kerf Glue Line Rip Blade, LM75R010.
I have recently saved the redwood from an 8 foot hot tub, but am having a terrible time in resawing the boards so I can use them. Each board is 5+" X 48 X 1 3/8, but curved like a barrel stave. If I had a 6" jointer, I could do it, but that would also sacrifice quite a bit of wood. I am thinking that if I first ripped each in half, then I could use my 4" jointer, then planer, than resaw the edges with this blade, and glue them up.
I welcome other thoughts on this.

JPG · Post by **JPG** » Fri Feb 15, 2013 11:59 am

tomp wrote:Has anyone used these blades? I am thinking of trying a Freud 10x30 Thin Kerf Glue Line Rip Blade, LM75R010.
I have recently saved the redwood from an 8 foot hot tub, but am having a terrible time in resawing the boards so I can use them. Each board is 5+" X 48 X 1 3/8, but curved like a barrel stave. If I had a 6" jointer, I could do it, but that would also sacrifice quite a bit of wood. I am thinking that if I first ripped each in half, then I could use my 4" jointer, then planer, than resaw the edges with this blade, and glue them up.
I welcome other thoughts on this.

Methinks this is a task for the bandsaw.

charlese · Post by **charlese** » Fri Feb 15, 2013 12:29 pm

Hi, Tom! As an old Montanan I'll try to give you the best answer I can think of.

The "curved like a barrel stave" is your biggest issue. However before doing any sawing/planing/jointing you need to make sure the boards are dry to at least 8 to 10% moisture content. You can do this by storing the boards in a dry place for several weeks.

To take cure the bow in the boards, I think your best bet is to crosscut each board into several pieces With each shorter board being relatively un-bowed you may be able to joint them. You need to realize that after flattening, each of the shorter boards will end up being less than the present thickness.

When jointing put the curved surface up and joint off the trailing edges in very small bites, until the blades touch the center of the board. reverse the board and do the other edge. You may be able do this more easily with a hand plane. Once the bottom of the board is flat, you can plane the top convex surface.

Ripping into narrower boards, will help this operation, is you intend to use the Shopsmith jointer. When ripping - make sure you have the concave surface down and have good hold down feather boards in place. (at least one pushing down and one holding the board tight to the fence)

When jointing the flat surface - take care that you don't push the high part of the board down so much as to press the curvature out of the board.

JPG · Post by **JPG** » Fri Feb 15, 2013 12:36 pm

charlese wrote:Hi, Tom! As an old Montanan I'll try to give you the best answer I can think of.

The "curved like a barrel stave" is your biggest issue. However before doing any sawing/planing/jointing you need to make sure the boards are dry to at least 8 to 10% moisture content. You can do this by storing the boards in a dry place for several weeks.

To take cure the bow in the boards, I think your best bet is to crosscut each board into several pieces With each shorter board being relatively un-bowed you may be able to joint them. You need to realize that after flattening, each of the shorter boards will end up being less than the present thickness.

When jointing put the curved surface up and joint off the trailing edges in very small bites, until the blades touch the center of the board. reverse the board and do the other edge. You may be able do this more easily with a hand plane. Once the bottom of the board is flat, you can plane the top convex surface.

Ripping into narrower boards, will help this operation, is you intend to use the Shopsmith jointer. When ripping - make sure you have the concave surface down and have good hold down feather boards in place. (at least one pushing down and one holding the board tight to the fence)

When jointing the flat surface - take care that you don't push the high part of the board down so much as to press the curvature out of the board.

I do not think he has the 'bow' problem. They were hot tub staves, not barrel staves. I assume the cross section is trapezoidal and constant end to end.

tomp · Post by **tomp** » Fri Feb 15, 2013 6:01 pm

I'm sorry for my lousy description.
Band saw? I guess I should have not used the word resawing.
JPG is correct, trapezoidal shaped, end to end. I'm too long from geometry to come up with that description. And my thoughts for using the glue-edged blade was for the final ripping cut. But I suppose I could just as well joint that edge after sawing it, if necessary.
I think I will cut them to 4" width, joint the concave 4" surface until flat, plane the opposing side, joint one edge to 90 degrees, and saw the opposite edge.
There are quite a few boards in an 8 feet diameter tub. The ones I have inside are plenty dry, but there are many more outside. I'll keep the drying in mind, Charlese.
Thanks!

reible · Post by **reible** » Fri Feb 15, 2013 6:36 pm

Hi,

I see the initial rip cuts as a potential problem. I agree that ripping them to allow the use of you jointer makes good since, and Charlese described the process well.

Here is the thing, where you to rip the boards at the table saw then which side should be up? If you put the rounded edge on the table then it would be "tippy". If run the other way the two contact edges are fine (if they don't happen to fall in a miter slot) until you are about to finish the cut.... when the blade finishes the cut the two sides will collapse against the blade. The one side will just slide away but the trapped side (fence side) could cause a kick back (actually this is potential problem in either case).

For this reason you may want to make a jig to hold the wood that rides against the fence and clamps the board. Safety first.

The bandsaw is another option, no kick back but potentially more difficult to hold the for the rip cut. Again safety first.

Now I have some questions, since this was a hot tub and I assume that like a pool chlorine is used, what the long term effects of chlorine on the wood? I know you can bleach wood but that is just a short term exposure where as a hot tub would have long term exposure. Just asking here as I have no ideas on the subject.

Ed

tomp · Post by **tomp** » Sat Feb 16, 2013 1:19 am

Those are some great thoughts, Ed. I'm glad that I didn't go thru with my plan. I too think there would have been kick-back. I sure don't need that.

After stewing over it for awhile, I finally decided not to rip the boards. I placed them concave side down on the planer, and slowly leveled the convex side. It worked well. The boards were 1 3/8" thick, so the planer rollers couldn't flatten them. I then turned them over and leveled the other side. Then the jointer on one edge. Those 3 sides are square. I will rip the other edge, do some resawing, and glue them up.

I don't know what to make of the chlorine. The hot tub has been empty for 15 years, but the boards seem fine. I had to finally tear the hot tub down because that is the area where my new shop resides. I originally threw all the redwood boards into my burn hole, but then thought better about it.