Should I be concerned with .003" gap?

[Jeff Norri]

A pannel bed I am working on has long butt joint with M & T joints at the top and bottom where the styles meet the legs. The butt joint is not required for strenth, but it has .003" gap. I have worked on the joint for a while and have taken it from a .005" gapped joint to the .003" gap. My question is will titebond III fill this gap? And if it will, will it add any stenght?

For the record we are talking about a gap so small my wife can't see it, a gap so small paper will not fit in it. I measured it useing a feeler gauge.

I am going to continue fitting it, but at this point I don't think I an get much smaller then .002. Clamps will pull it together, but will the glue hold up in a sprung joint like this? Should I use a differnet glue?

The attached drawing may explain things better (the arrows point to the "problem area").


PS: feel free to tell me I am being way too anal.

[mark page]

Geez, half the time my normal milling doesn't get that close. Normal wood movement will be more than that. It looks like its going to be a side grain to side grain glue joint, so glue it then clamp it. It should hold perfectly. TB II or III glue will work fine for this.

[Roger Newby]

You shouldn't have any problem with .003" gaps. A lot of us are happy to get down to a 64th, which is five times as much. If you're hitting .003" you should be proud of yourself.

[glenn bradley]

Normal wood movement will alter that back and forth. I'd say you're good.

[David Duke]

PS: feel free to tell me I am being way too anal.

You said it .

In all seriousness if when you clamp it up tight, the glue will hold it together with no problems.

[Pete Brown]

If you were machining a steel cylinder for a piston, I might argue that tolerance isn't great. For wood, you're well within what is acceptable, IMHO.

It's good to hold yourself to high standards, but if you are really at .003" (how on earth did you see that, let alone measure it) you're doing well. Don't sweat the small stuff

The water-based glue will probably swell the wood more than that.

Pete

[Chris Foley]

If you were machining a steel cylinder for a piston, I might argue that tolerance isn't great.

Okay...I have to be the smarty-pant$ in the group today. lol Actually, for many pistons, a 0.003" gap is good. The pistons need the clearance so that never touch the cylinder wall.....

Okay...smarty-pant$ moment is over....we will now continue with our regularly scheduled programming.

[Pete Brown]

Okay...I have to be the smarty-pant$ in the group today. lol Actually, for many pistons, a 0.003" gap is good. The pistons need the clearance so that never touch the cylinder wall.....

Okay...smarty-pant$ moment is over....we will now continue with our regularly scheduled programming.

You know, when I wrote that I thought "I bet there's a machinist on this forum that is going to point out a flaw in that statement". lol. There you are

For what its worth, I've only done machining for models. My smallest ball end mill is 0.005". It's painful when I break those.
http://www.irritatedvowel.com/Railro...ndCasting.aspx

Pete

[Mike Vermeil]

How the heck did you measure a 0.003 gap in wood? Feeler gauge?

[Michael Schwartz]

Wood moves more than .003

You are doing pretty good work if you are getting a fit closer than a hundredth of an inch. 1/64" is good enough for government work.

[Ken Shoemaker]

HOLY CRAP!!! .003??? Are you kidding!!!! The best joint I ever had I used a puddy knife as a feeler gauge to measure the gap and was darn proud when only three would fit in there.... I think ya" dunn good... Glue, clamps, and enjoy!!! Ken

[Gary Whitt]

PS: feel free to tell me I am being way too anal.

Yes.

Don't sweat the small stuff.

.003

[harry strasil]

I went to a guild meeting in a large town once, a retired machinist was using machine tools to work on wood and talking about fits in the thousands range.
I got to laughing so hard, I almost got evicted when a fellow neander setting with me commented, "Jeez, he's doing microscopic brain surgery on wood".

Personally, I prefer a light drive fit and drawboring and pegging with no glue. of course I am a neanderthal.

No offense intended, and I hope non taken.

[Jeff Norri]

Thanks for all the advice. Time to move forward then!

[david babcock]

Thanks for all the advice. Time to move forward then!

ya. showoff.