LumberJocks

All Replies on how tight do i clamp?

  • Advertise with us
View bygrace's profile

how tight do i clamp?

by bygrace
posted 08-06-2016 12:08 AM


16 replies so far

View nightguy's profile

nightguy

213 posts in 1058 days


#1 posted 08-06-2016 12:29 AM

Could have been to tight, snug is good, could have been the edge to face was not a perfect 90*. Hard to say, since not being there.. For sure snug or just past it is sufficient for clamp pressure..

View AlaskaGuy's profile

AlaskaGuy

5284 posts in 2705 days


#2 posted 08-06-2016 12:30 AM

I used 2×6 isn’t a lot of information.

-- Alaskan's for Global warming!

View KelleyCrafts's profile

KelleyCrafts

3717 posts in 1135 days


#3 posted 08-06-2016 12:38 AM

Construction lumber? If so how long before the cupping appeared after gluing?

-- Dave - http://kelleycrafts.com/ - pen blanks - knife scales - turning tools

View TheFridge's profile

TheFridge

10858 posts in 1882 days


#4 posted 08-06-2016 01:01 AM

Happens to me all the time even with cauls.

-- Shooting down the walls of heartache. Bang bang. I am. The warrior.

View bygrace's profile

bygrace

198 posts in 2365 days


#5 posted 08-06-2016 01:20 AM

nightguy, I milled all the lumber before glue up, so they should’ve been 90*. But I did screw down on the pipe clamps pretty much as tight as I could so I’m thinking that’s what did it, just wasn’t sure.

Alaska guy, sorry about that. I did use construction lumber (Fir). Most of the farmhouse tables are built with it, with hardwood offered by some as an up grade.

ki7hy, I noticed it the next day after I left it to dry overnight.

TheFridge, Cauls. Thanks. I knew there was a name for those! would have been much easier to understand if I had remembered.

-- Andy, Waxahachie, Tx.

View nightguy's profile

nightguy

213 posts in 1058 days


#6 posted 08-06-2016 01:22 AM

I guess trying to make fine furniture from construction lumber is an oxymoron!! If that is the look you want though that is what to use, and old pine back then was different then good pine now a days.

View nightguy's profile

nightguy

213 posts in 1058 days


#7 posted 08-06-2016 01:25 AM

Was that 2×6 pine or Douglas Fir, big difference, 2 different species?

View bygrace's profile

bygrace

198 posts in 2365 days


#8 posted 08-06-2016 01:36 AM

True nightguy! this is what people are buying right now. Not my first choice either, but I need to support my habit and the tools I need to move forward.

-- Andy, Waxahachie, Tx.

View nightguy's profile

nightguy

213 posts in 1058 days


#9 posted 08-06-2016 01:48 AM



True nightguy! this is what people are buying right now. Not my first choice either, but I need to support my habit and the tools I need to move forward.

- bygrace

Gotta do what you gotta do!!!!!!!!!!!

View 000's profile

000

2859 posts in 1295 days


#10 posted 08-06-2016 02:02 AM

”how tight do i clamp?”

Apparently, as tight as you can… LOL

View jumbojack's profile

jumbojack

1688 posts in 3020 days


#11 posted 08-06-2016 02:39 AM

Generally, only tighten enough to close the gap and produce beads of squeeze out. Sometimes it also helps to alternate the end grain structure. That is ring smiles up and down. Further if you brought the lumber home cleaned them up and glued them you glued up wet lumber. It is difficult to get dry lumber at the box store. If I need to use the lumber right away look for kiln dried lumber. For best results look for grain the fund up and down rather than smiles. You can usually get really good lumber cutting 2×10s or even 2×12s. You will usually find some pretty fine lumber this way. The cost and waste is higher but you get a quality product.

-- Made in America, with American made tools....Shopsmith

View Robert's profile

Robert

3405 posts in 1876 days


#12 posted 08-06-2016 11:33 AM

Ease up, NG. He’s a beginner asking questions. Obviously its not fine furniture if you read the post he said it was a farmhouse table.

bygrace,

Pipe clamps tightend that tight can cause a panel to bow. Counteract this tendency by alternating clamps over and under.

Another thing to look at is milling. What I do is lay out the top, draw a big triangle to keep the boards oriented, and alternate faces against the jointer fence. Any tendency for angles to be off will cancel out giving a perfect 90.

You don’t need to crank extremely tight. How tight? When the boards close up and the glue line appears, I turn it just a little more, that’s all. More than that, you’re going to cause a panel to bow the wider the worse.

With tables of this type with this type of lumber I suggest using an alignment method such as biscuits, dowels, or a spline. You could even tongue and groove.

Good luck hope you got your answer.

-- Everything is a prototype thats why its one of a kind!!

View GR8HUNTER's profile

GR8HUNTER

6110 posts in 1108 days


#13 posted 08-06-2016 03:26 PM



Ease up, NG. He s a beginner asking questions. Obviously its not fine furniture if you read the post he said it was a farmhouse table.

bygrace,

Pipe clamps tightend that tight can cause a panel to bow. Counteract this tendency by alternating clamps over and under.

Another thing to look at is milling. What I do is lay out the top, draw a big triangle to keep the boards oriented, and alternate faces against the jointer fence. Any tendency for angles to be off will cancel out giving a perfect 90.

You don t need to crank extremely tight. How tight? When the boards close up and the glue line appears, I turn it just a little more, that s all. More than that, you re going to cause a panel to bow the wider the worse.

With tables of this type with this type of lumber I suggest using an alignment method such as biscuits, dowels, or a spline. You could even tongue and groove.

Good luck hope you got your answer.

- rwe2156

True that …... he knows what he says

-- Tony---- Reinholds,Pa.------ REMEMBER TO ALWAYS HAVE FUN

View bygrace's profile

bygrace

198 posts in 2365 days


#14 posted 08-06-2016 09:28 PM

jbay, ok, your right, How tight SHOULD I clamp.

jumbojack and rwe2156, thanks for your input. Some is good advice I’ve heard before but have forgotten, other is new to me so thank you very much!

-- Andy, Waxahachie, Tx.

View 000's profile

000

2859 posts in 1295 days


#15 posted 08-06-2016 10:00 PM


jbay, ok, your right, How tight SHOULD I clamp.

jumbojack and rwe2156, thanks for your input. Some is good advice I ve heard before but have forgotten, other is new to me so thank you very much!

- bygrace

bygrace, I give the clamps a good snugging. Then, depending what it is, (a glue up) after about 15 minutes
I go around and give them another smidge.
I don’t try to tighten them with all my mite, just good and tight.
As also said clamp on top and on bottom. Even though your using cauls, with clamps only on one side your compressing the wood fiber more on that side. Best to use 2 clamps and compress the edge evenly

View jdh122's profile

jdh122

1073 posts in 3213 days


#16 posted 08-06-2016 10:24 PM

Curved cauls instead of straight 2X4s will also help. With a jointer they’re really easy to make: http://www.finewoodworking.com/how-to/video/how-to-make-cambered-cauls.aspx. Otherwise you can also make them with a handplane quite easily.

-- Jeremy, in the Acadian forests

Have your say...

You must be signed in to reply.

DISCLAIMER: Any posts on LJ are posted by individuals acting in their own right and do not necessarily reflect the views of LJ. LJ will not be held liable for the actions of any user.

Latest Projects | Latest Blog Entries | Latest Forum Topics

HomeRefurbers.com