Pelican Parts Forums

Pelican Parts Forums (http://forums.pelicanparts.com/)
-   Off Topic Discussions (http://forums.pelicanparts.com/off-topic-discussions/)
-   -   joining 2 boards end to end, best method, dowels? (http://forums.pelicanparts.com/off-topic-discussions/471019-joining-2-boards-end-end-best-method-dowels.html)

masraum 04-25-2009 07:48 PM

joining 2 boards end to end, best method, dowels?
 
If you had to join 2 boards (3/4" pine) end to end and wanted them to line up, how would you do it? biscuits, dowels, tongue and groove?

Then, what are the tricks? There's gotta be tricks, there always are. Woodworking is as much an art as a science.

BRPORSCHE 04-25-2009 07:54 PM

I have used biscuits with gorilla glue on oak to make wood flooring. It was extremely strong.

gassy 04-25-2009 07:55 PM

For what application?

TimT 04-25-2009 07:59 PM

Biscuits..

Last year I did the deck on my house in Vermont with blind fasteners and biscuits..still looks amazing after its first severe winter.

Why do you need to join wood on end grain?

masraum 04-25-2009 08:27 PM

I needed a 10' piece of 1x12 premium pine (really only needed just barely over 8') and my local hardware stores didn't have it, so I'm going to make it. The joint won't be structural.

dad911 04-25-2009 08:51 PM

If you don't have dowel jig or biscuit joiner, you can cut both ends on 45, giving a larger area to glue and clamp. then short nails or screws from backside.

If it is just over 8', how about an 8' board, then 1x4 etc at both ends, running the grain at 90 degrees to the original 1x12, to add a decorative end?

89911 04-26-2009 02:51 AM

You can do this numerous ways with varying degrees of perfection and strength. First, you have to make sure the boards are flat and don't have a noticeable cup to them. They also have to have a straight edge, which they usually don't unless they have been run on an edger. If they fit together reasonable well (again, this could vary from building a shelf to making a fine cabinet) you could simply apply would glue, line up the edges and clamp them with pipe clamps. If you want reinforcement, dowels or biscuits can be used. Dowels are simplier because all you need is a placement tool to align your drilling, a drill and bit, and the dowels. The biscuit jointer is better, but then again, you have to borrow or buy one. If I need a board wider then 12", I usually use veneered plywood, cut and rip the the size I need, and add a cover trim piece on the edges. The plywood usually takes out the issues with warping, cupping, and uneven seems where they have been joined.

ednj 04-26-2009 03:01 AM

http://www.kregjoint.com/index.php?p=faq

Kreg website

Kreg Jr.

Porsche_monkey 04-26-2009 04:47 AM

Look at hardwood floors....sort a V and a notch.

HardDrive 04-26-2009 08:57 AM

http://www.rsvppost.com/wp-content/u...ct-tape-3m.jpg

Zeke 04-26-2009 09:02 AM

Kreig is good, but he may not have the tool. The beveled overlap is called a scarf and gives more glue area. Non structural, I'd just glue a scarf and tack it. clamp up until dry.

Porsche-O-Phile 04-26-2009 09:08 AM

+1 for a good biscuit joiner.

masraum 04-26-2009 09:29 AM

Thanks all, lots of good responses.

masraum 04-26-2009 02:34 PM

Quote:

Originally Posted by dad911 (Post 4628411)
If you don't have dowel jig or biscuit joiner, you can cut both ends on 45, giving a larger area to glue and clamp. then short nails or screws from backside.

If it is just over 8', how about an 8' board, then 1x4 etc at both ends, running the grain at 90 degrees to the original 1x12, to add a decorative end?

I tried to make my own dowel jig, and got it close, but not quite. I was at HD earlier and noticed that they had a dowel jig there for purchase, but don't know that I'd use much so decided against it.

I like the idea about the 1x4s at the end, but while not structural, the ends may have a little stress. I decided to get a biscuit joiner instead. I've needed one in the past, and suspect I'll need one again some time, so I figured for $100 it was a good deal.

I read up on "scarfing" a bit. I read one webpage that said that the recommended ratio is 12:1 for length of glue area vs thickness. Wow, how in the hell could you get a 12:1 ratio on anything other than 2/2 or 1/2 or maybe 1/4? That's a pretty shallow angle. I'm sure under most circumstances, 45* would be fine.

Thanks again all.

dad911 04-26-2009 02:56 PM

Well, you said it wasn't structural, so it is common when installing long trim moldings(base, crown, etc) to bevel rather than butt seams. That way if/when it shrinks a little, it doesn't leave a gap.

More specifics may have yielded a better solution.

Now that you have a biscuit joiner, depending on your application, you can also use 1x6 and stagger the joints, and join the edges. Or use longer 1x6. Joint lengthwise may be less visible than a butt joint.

masraum 04-26-2009 04:45 PM

Quote:

Originally Posted by dad911 (Post 4629562)
Well, you said it wasn't structural, so it is common when installing long trim moldings(base, crown, etc) to bevel rather than butt seams. That way if/when it shrinks a little, it doesn't leave a gap.

More specifics may have yielded a better solution.

Now that you have a biscuit joiner, depending on your application, you can also use 1x6 and stagger the joints, and join the edges. Or use longer 1x6. Joint lengthwise may be less visible than a butt joint.

That's an excellent idea. I wish I'd have thought of it before. Oh well. That's what I get for asking at the onset instead of a few days prior to starting work.

I'll mental note that one for next time. I'm still very much in the baby/learning to crawl stages of working with wood. I really enjoy it but don't do it often enough. What I really need is someone like Dad911, Milt, or any of the other experienced carpenter type guys for a neighbor to consult with over a beer when I start these little projects.

mike55 04-26-2009 04:56 PM

If you have access to a local mill, ask them to finger joint the ends - it'll never come apart. Otherwise, I'd use couple of biscuits or cut the ends at a 45. Good glue helps too.

Tim Hancock 04-26-2009 05:06 PM

Aircraft wood spars are often scarfed and the resulting joint is just as strong (if not stronger than the wood itself). I typically go about 15:1 by running a router mounted to a wide base plate over two sloped rails straddling the board at the end being scarfed. Works pretty slick.

I have also scarfed 1/8 aircraft plywood... that was a real beotch using a belt sander to create the feathered edge. Thankfully I only needed to scarf about 16" on the four parts needing to be joined.

This main wing spar here is made of laminations of perfect tight grained quarter sawn douglas fir boards. It has several scarf joints buried in the layers. It is good for over 10 g's positive/negative. I glued it up using West Sytem epoxy.

(I have a 35mm pic somewhere of my scarfing operation, but I don't know where)

http://forums.pelicanparts.com/uploa...1240794172.jpg
http://forums.pelicanparts.com/uploa...1240794231.jpg
http://forums.pelicanparts.com/uploa...1240794274.jpg

Zeke 04-26-2009 05:13 PM

Biscuits are for edge joining, whether it is be flat or angled. End joining is done with dowels for tensile strength. Kreigs are a form of dowel. You said it was non structural, so the long scarf is not needed.

javadog 04-26-2009 05:49 PM

I would have bought the wood at a lumber yard, gotten the length I needed in the first place, and been done by now.

Seriously, this is too much work to make something that isn't hard to find.

Good luck,
JR

avi8torny 04-26-2009 06:05 PM

Kreg

dipso 04-26-2009 06:44 PM

Take a circular saw and cut the 8' piece into 8 12"x12" squares. Throw 7 of those into the fireplace.
Take the last piece and balance it on top of the door.
Now go get the phonebook and find the nearest lumber yard.

On the way out the piece of wood on the door should fall and leave a nice bump on your head. That will serve as a reminder that you can't make an 8'6" length of board out of an 8' piece of wood.

Unless you have a wood stretcher.
:D

masraum 04-26-2009 07:38 PM

Quote:

Originally Posted by Tim Hancock (Post 4629761)
This main wing spar here is made of laminations of perfect tight grained quarter sawn douglas fir boards. It has several scarf joints buried in the layers. It is good for over 10 g's positive/negative. I glued it up using West Sytem epoxy.

Tim, don't take this the wrong way, but you're freakin' insane!!! Wow, serious workmanship there. Very cool! Thanks for the pics.

masraum 04-26-2009 07:39 PM

Quote:

Originally Posted by milt (Post 4629773)
Biscuits are for edge joining, whether it is be flat or angled. End joining is done with dowels for tensile strength. Kreigs are a form of dowel. You said it was non structural, so the long scarf is not needed.

Thanks, this thread will be very educational if nothing else which is fantastic.

masraum 04-26-2009 07:41 PM

Quote:

Originally Posted by dipso (Post 4629920)
Take a circular saw and cut the 8' piece into 8 12"x12" squares. Throw 7 of those into the fireplace.
Take the last piece and balance it on top of the door.
Now go get the phonebook and find the nearest lumber yard.

On the way out the piece of wood on the door should fall and leave a nice bump on your head. That will serve as a reminder that you can't make an 8'6" length of board out of an 8' piece of wood.

Unless you have a wood stretcher.
:D

Hilarious! Yeah, it's just sooo easy to be lazy when there's a HD less than a mile away, a Lowes less than 3 miles away, and the nearest lumber yard (that I know about) is 15-20 miles away.

I considered trying to find the right size and the slacked out of it with "I can make it work."

911pcars 04-26-2009 11:03 PM

Quote:

Originally Posted by javadog (Post 4629834)
I would have bought the wood at a lumber yard, gotten the length I needed in the first place, and been done by now.

Seriously, this is too much work to make something that isn't hard to find.

Good luck,
JR

3/4" pine? How much longer? I gotta agree with JR's suggestion. Spend $99 or ?? instead of buying a longer piece of pine board? Uh, no.

Sherwood

911Rob 04-26-2009 11:21 PM

+1 on a different lumber yard.
Or just leave a 6" gap at the bottom/floor, no one ever looks there and if they do it'll be a conversation piece?

the duct tape pic was LOL!

RWebb 04-27-2009 10:47 PM

here is the problem

wood is made of a bundle of straws - tiny ones

when you try to glue any wood end to end - the straws absorb the glue -- they suck it away from the joint by capillary action -- so the joint is weak or worthless

if you use an expanding type glue, a non-wood glue this will be minimized

if you stick something in holes cut into either end and then glue that, then the biscuit or dowel is glued to each board by being glued to the sides of all those little tubes on each board.

I too would find the right board - then the grain will line up.

masraum 04-28-2009 08:49 AM

Yes, I should have gotten the right size lumber, but I didn't. Thanks for the suggestions. At least now I've got a cool tool for future stuff.

onewhippedpuppy 04-28-2009 09:26 AM

Next time find a real lumberyard. HD or Lowes are a joke for lumber, you're paying more for inferior quality, especially when it comes to hardwood. 15-20 miles is nothing compared to the hassle involved.

To the original question, I would also vote for the pocket hole (kreg). My father-in-law builds cabinets, he uses pocket holes for all of his face-frames and much of his other joining. But none of the listed methods will work well without uniform planed and edged boards. Assuming you don't have a planer and edger, just go buy a new board.


All times are GMT -8. The time now is 09:52 PM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2025, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2025 Pelican Parts, LLC - Posts may be archived for display on the Pelican Parts Website


DTO Garage Plus vBulletin Plugins by Drive Thru Online, Inc.