End Grain Gluing Question

[rincewind03060]

I have been given to understand (by a multitude of different woodworking books and articles) that an end grain to end grain joint is the weakest possible joint. How does that apply to smaller objects like segmented pens? I assume that in the usual pen design that the tube is providing significant structural strength.

But, what if I'm making a dip pen or some other design that doesn't contain a tube? Will an end grain to end grain joint be strong enough to hold up in those cases?

 

[Ron in Drums PA]

Originally posted by rincewind03060

Will an end grain to end grain joint be strong enough to hold up in those cases?

Simple answer, it will break.

Why not build your segments onto a small wooden dowel?

 

[fritz64]

it will break but not at the glue line.

 

[alamocdc]

Bob, Ron is dead on, but my experience is different from Robert's. Every failed end grain joint I've experienced broke at the glue line. I've tried biscuits and even plywood splines to reinforce the joint (larger pieces than for pens, mind you) and none of these have held up to any stress.

 

[Ron in Drums PA]

Originally posted by fritz64

it will break but not at the glue line.

You must be thinking of a face grain to face grain joint

 

[Hello]

I treid it recently and had seen info to the same idea...that end grain to end grain would break. I'd done pretty much what Ron had said. I drilled a 7mm hole through each segment that would cross the "center line" of the the barrel I'd be working with, turned the piece to a spindle, then drilled (very carefully) the spindle with the bit I wanted and gobbed a bunch of glue in. I may have just ben lucky, but mine didn't break - until I dropped the finished pen down the steps out front :-(

 

[jjudge]

endgrain to endgrain is a weak joint.

Here are some half-though-through ideas, based on what I'd do with larger woodworking:

if I were gluing up (end-to-end) pieces of wood to make a normal pen, then I'd not worry.
You have that brass tube up the inside ... so sidegrain is glued to the tube.
This should be enough to help hold it.

Dip pen? or some other solid pen body?
OK, I'd consider drilling up the inside and gluing a dowel to help.
I'd "size" the ends before gluing (so the glue won't wick away so much).

Worst case ... I'd try having tenons sticking out each piece's end and having a "socket" to mate it to the other piece. This would help with some sidegrain-to-sidegrain strength.

-- joe

 

[devowoodworking]

Have a look at some of the segmented vases and bowls made with very thin thicknesses, of course care must be exercised when turning, sharp tools and a light touch are a must. I've made several segmented pen cases and they were no problem at all.

 

[rincewind03060]

Thank you all!
some very good suggestions there.

 

[mwenman]

I turn quite a few segmented bowls and vases and have had a few end grain failures . As you have been told and others have said as well, gluing end grain will in fact be the weakest type of joint and more often than not will break on the glue joint itself. As with any glue joint, it is imperative that you have a smooth sanded surface and when glueing, make sure no debris or dust(within reason) enters into that joint.

Additionally, once your first ring is completed, make sure you stagger or offset the joint lines for the next layer you apply such as a brick layer does This will increase the overall strength since you will have surface area bridgeing the gap across the end joint below.

 

[Hosspen]

You may want to try this tip I heard at a woodturners meeting- When making segmented vases with a lot of end grain joints, first mix your wood glue with water 50/50 and coat the end grain of each piece with this and let it dry before gluing with your full strength glue. Apparently this seals the ends so they don't wick all the glue out of the joint? I'm no expert at turning, but many of the guys in that turning group are very very skilled so I listen when they speak. It may be worth a try. It sounds simple enough and doesn't cost much to find out. There are probably members here who can tell you more about this solution or another one. Good luck with your segments!