scarfing cedar strip

Looking for advice on scarfing the strips. Iv'e read some of the glue vs. epoxy post. I did the clc way and the bond didn't hold. I believe the clamp pressure was to great and caused to much sqeeze-out. What are good ways to hold the scarfs together while the epoxy or glue set up. Also ideas on actually cutting the scarfs.


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RE: scarfing cedar strip

I've been using this sander...

but with a similar fence set at a 8 to 1 ratio. It makes repeatable, safe scarfs. I've been gluing them with wood glue (if I'm not in a hurry) or CA glue (if I am)

Dan

RE: scarfing cedar strip

Not long ago, I saw a industry comparison that stated Tite-Bond III holds it's 'grip' as well as epoxy.  In the past, I have used Tite-Bond III and have NEVER had a failure.  It's nice to see it in writing.  Much more cost effective as well.....    ~BRUCE~

RE: scarfing cedar strip

I also use TB-III and there's a couple of things to keep in mind when using it for boats. First, it does not fill gaps. Second, the manufacturer says that it shouldn't be used below the waterline.

I'm not too concerned about that second issue. Not only because everything gets covered with glass/epoxy, but because no glue manufacturer seems towant to claim that their product is truly waterproof. It's like all the rope manufacturers who don't want their rope used to lift anything off the ground. Sometimes I think that all any of them want is for us to buy their product, throw it away unopened and buy some more.

Not filling gaps is a real issue. It means that for maximum strength the quality of the woodworking has to be high enough such that there aren't any gaps in the joints. Not a problem, just something to be aware of. So for complex irregular joints I use epoxy, for smooth regular ones I use TB-III

TB-III also needs more clamping pressure than epoxy does.

Laszlo

 

RE: scarfing cedar strip

Laszlo is correct. Good fit, continuous contact- TB111 with pressure works for me, if there are gaps- thickened epoxy. 

Lew 

RE: scarfing cedar strip

Dan,

What is your impressions of the Rigid Sander. I've been looking at this as a fixed sanding setup, being the tool junkie that I am.

Is this worth buying?

Mike

RE: scarfing cedar strip

I like it, Mike. Definitely worth it. It converts to a spindle sander also with an assortment of sizes. It's been much more useful than my bench belt/disc sander.

Dan

RE: scarfing cedar strip

I hardly touched a clamp to glue the scarfed strips together on our two Shearwater Hybrids.  I tightly screwed two 16" boards to a support board underneath with a cedar strip enclosed in plastic between the screwed boards. I then carefully cut the first scarf at 8:1 and then cut the second to fit the first.  I placed the plastic back in the created groove, put the glue on the joints, and slid them together in the slot.  It is a little cold on the floor where I'm glueing, so I put a lamp to heat up the glue joint and the glue container sitting along side the joint. Six hours later, I just had to pull up on the plastic and the scarf joint is finished.  

RE: scarfing cedar strip

I cut scarfs in pairs, that way they will match. Stack strips, pencil in a mark (8:1 - 12:1) and whack it down with a sharp plane. I have used a sled on a table saw and a router jig, but just nipping off a scarf with a sharp plane is faster and less noisy.

Glue? Epoxy is my fav, but I have also used Titebond II and on occasion Titebond III. All work, but epoxy set time is more reliable since I'm in a coastal area and swamp humidity can slow down Titebond.

If you're strip building as in canoe/kayak forget scarfing. Just trim ends square of disk sander and butt glue with Titebond in situ, as on the fly. Multiple strips, sheathed both side in glass, no proiblem. Works for me.

RE: scarfing cedar strip

RE clamp pressure. Titebond likes to be clamped tight. Epoxy not so much.  Epoxy precoat surfaces and let it soak in, then glue with epoxy filled with microfibers = little looser than peanut butter - and focus on lining parts up with just enough clamping to hold them in place. 

For wood structure home built aircraft the FAA requires epoxy joints to have a "pencil line width" glue seam. Squeeze it all out and your plane fails inspection. Just because a boat floats instead of flys doesn't change epoxy specs. 

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