Joining boards along their length - Page 3 - Router Forums
 26Likes
Reply
 
LinkBack Thread Tools Display Modes
post #21 of 40 (permalink) Old 10-13-2019, 09:07 PM
Registered User
 
graeme.c.payne's Avatar
 
Join Date: Jun 2017
Country: United States
First Name: Graeme
Posts: 127
 
Default

The only things I've used PU adhesive for is to bond different construction materials - such as steel stud channels to concrete. I don't think I've ever thought of using it for woodworking ...

I have stuck mostly with yellow glue and it's relatives, or resorcinol when the bond had to be waterproof. I have experimented with epoxy on wood in the past week - I'm waiting to see how that works out.
graeme.c.payne is offline  
Sponsored Links
Advertisement
 
post #22 of 40 (permalink) Old 10-13-2019, 09:40 PM
Forum Contributor
 
Stick486's Avatar
 
Join Date: Jan 2013
Country: United States
First Name: Stick
Posts: 26,142
 
Default

try Weldbond...

.
Attached Files
File Type: pdf Weldbond Specifications & Instructions.pdf (82.1 KB, 19 views)

This would have been the week that I'd have finished chewing thru the restraints...
If only new layers hadn't been added....

Stick....
Forget the primal scream, just ROAR!!!
"SNORK Mountain Congressional Library and Taxidermy”
Stick486 is online now  
post #23 of 40 (permalink) Old 10-13-2019, 10:50 PM
Forum Contributor
 
Stick486's Avatar
 
Join Date: Jan 2013
Country: United States
First Name: Stick
Posts: 26,142
 
Default

Quote:
Originally Posted by graeme.c.payne View Post
The only things I've used PU adhesive for is to bond different construction materials - such as steel stud channels to concrete. I don't think I've ever thought of using it for woodworking ...

I have stuck mostly with yellow glue and it's relatives, or resorcinol when the bond had to be waterproof. I have experimented with epoxy on wood in the past week - I'm waiting to see how that works out.
are you referring to PU construction adhesive like PL400 and PL Premium...

This would have been the week that I'd have finished chewing thru the restraints...
If only new layers hadn't been added....

Stick....
Forget the primal scream, just ROAR!!!
"SNORK Mountain Congressional Library and Taxidermy”
Stick486 is online now  
Sponsored Links
Advertisement
 
post #24 of 40 (permalink) Old 10-14-2019, 01:57 AM Thread Starter
Registered User
 
1fizgig's Avatar
 
Join Date: Feb 2018
Country: Australia
First Name: Steve
Posts: 990
 
Default

Quote:
Originally Posted by mgmine View Post
You are asking how to make the boards longer not wider. The way it is done is with finger joints. You can buy a bit or do it on a saw.

https://woodgears.ca/box_joint/fingerjoint.html
Thanks Art, but no, I am trying to make a wider board, not a longer board. Length (1600mm) is not the issue, but I need that board to be 450mm wide. Currently I can source 405mm wide @ 1800mm long, so I can cut the length down, but it isn't wide enough.

Hope that makes it clearer.
1fizgig is offline  
post #25 of 40 (permalink) Old 10-14-2019, 02:36 AM Thread Starter
Registered User
 
1fizgig's Avatar
 
Join Date: Feb 2018
Country: Australia
First Name: Steve
Posts: 990
 
Default

Okay, I'll do my bit to answer a number of points made so far.

First though, thanks for all the input and discussion, very enlightening and I appreciate you all sharing your knowledge and experiences.
@Stick486 : Thanks, that's a lot of good info. Baltic Birch isn't really available here in Australia so much (I haven't found much) and it's often made into ply with other woods, and not in thin sizes. @Biagio : I don't have a slot cutter at this time. Not to say I can't get one, so it's an option.

I am concerned though that if the material I'm working with is only 18mm thick (not quite 3/4") that I would be hogging out quite a bit of material. Would I opt for say a 6mm thick spline?

Biagio: Regarding the position of the glue-line,
1. Will it be visible inside the cabinet? Yes it will
2. Will the board be weight-bearing? Yes it will
3. Are there any other structural members to give support? Yes there are, note I mentioned supports in the original post.
4. Exactly what material are you using? If by laminate you mean melamine-faced, it is darn difficult to get an invisible glue line. In that case, you might want to position the glue line as far towards the back as possible. Also, the factory edges will possibly be more chip-free than you or I can achieve by cutting. Ditto for the edging. If the laminate is wood veneer, it may not matter so much.

Steve: The laminate I refer to is glue-lam beech. No melamine involved
I suspect hiding the glue line won't be an issue, nor will I need to hide the ends as they will be contained within the sides of the cabinet.
I've attached a sample pic of the glue-lam sheet I talk about for reference.

Biagio: I understand it to be that he wants a board 1600mm long and 450mm wide, but the standard width is only 405mm. Hence he wants to join two boards of 405mm along their long edges, and then cut off the extra. The question is whether to have the joint in the middle of the board, or to one side (i.e. one of the joined boards would land up being only 45 mm wide).
If this is the base of the cabinet, and not particularly visible from the inside of the cabinet, I would opt for the simplicity of the unequal widths.

Steve: Correct on the orientation of the board and cutting off the excess. I thought about unequal widths, however my concern about that was about the weight-bearing aspect and whether or not supporting it directly would prove stronger. I've attached also the sketch of the design to provide more clarity.
Note that the sketch is not entirely finished, but it shows the general design idea.
Attached Thumbnails
Click image for larger version

Name:	IMG_2919.JPG
Views:	25
Size:	97.9 KB
ID:	375383  

Click image for larger version

Name:	Sketch of buffet.JPG
Views:	26
Size:	27.8 KB
ID:	375385  

1fizgig is offline  
post #26 of 40 (permalink) Old 10-14-2019, 02:40 AM Thread Starter
Registered User
 
1fizgig's Avatar
 
Join Date: Feb 2018
Country: Australia
First Name: Steve
Posts: 990
 
Default

In the sketch you can see the two supports that will be underneath coming up from the stretcher along the middle. There will be a solid board in between the cupboards and drawers to which the baseboard will also be attached. All the grain/figure of the beech will be running horizontal across the piece (looking at it from the front).
1fizgig is offline  
post #27 of 40 (permalink) Old 10-14-2019, 03:58 AM
Forum Contributor
 
Stick486's Avatar
 
Join Date: Jan 2013
Country: United States
First Name: Stick
Posts: 26,142
 
Default

Quote:
First though, thanks for all the input and discussion, very enlightening and I appreciate you all sharing your knowledge and experiences.
@Stick486 : Thanks, that's a lot of good info. Baltic Birch isn't really available here in Australia so much (I haven't found much) and it's often made into ply with other woods, and not in thin sizes.
that's what I was saying to use... BB plywood... (or comparable)...
https://dmkforestproducts.com.au/contact/
Richwise Australia Pty Ltd - Australian importers and wholesalers of Russian Birch Plywood
https://www.perthtimberco.com/plywood/
and there's Yates in Sydney, Mister Plywood and Amerind....

6mm is your target thickness..
3mm will work..
9mm is too much...

Quote:
I am concerned though that if the material I'm working with is only 18mm thick (not quite 3/4") that I would be hogging out quite a bit of material. Would I opt for say a 6mm thick spline?
spline thickness, as a rule of thumb, is usually 1/3 of the overall material thickness...
so you won't be hogging out too much at all..
a spline is a good fit and not gaped like a tongue and groove...

Quote:
I've attached a sample pic of the glue-lam sheet I talk about for reference.
perfect for splining....

This would have been the week that I'd have finished chewing thru the restraints...
If only new layers hadn't been added....

Stick....
Forget the primal scream, just ROAR!!!
"SNORK Mountain Congressional Library and Taxidermy”
Stick486 is online now  
post #28 of 40 (permalink) Old 10-14-2019, 10:53 AM
Registered User
 
Join Date: Mar 2013
Country: South Africa
First Name: Biagio
Posts: 348
 
Send a message via Skype™ to Biagio
Default

Steve,
I am no engineer, and defer to greater knowledge and experience, but I would think that if you are only adding 45mm width at the back of the board, it is unlikely that you could put anything heavy enough on the narrow section, to cause a joint failure. You are not planning on putting 20kg barbell plates upright on edge, behind the soup bowls, perhaps?
As for the strength of the carcass overall, the full width of the 405mm board should be enough to support the top, dancing girls and all. Having a joint down the middle of the base would have no effect - it cannot increase the tensile strength above that of the unjoined material. You are supporting the base, as indicated in your sketch, so there should be no sagging. If you are worried, you might need to double up on the board (to 36mm thickness). Remember the load is not distributed just at the ends of the 1600mm length - you have an upright divider. If still unsure, ask Cherryville Chuck to calculate the forces for you.
Apologies, by the way, I noticed after posting that you had mentioned supporting members. And you are right about the glue line - you can hide it among all the other “glue lines” in the pattern.
I am envious that you can get birch lam - we can only get pine lam, and that is expensive enough.
BTW, I looked up some of the suppliers Stick listed - looks like you would be in for a full sheet of BB in order to cut off a spline. Unless the barbell plates are a definite, I would stay with dowels.
1fizgig likes this.
Biagio is offline  
post #29 of 40 (permalink) Old 10-14-2019, 05:24 PM
Forum Contributor
 
Stick486's Avatar
 
Join Date: Jan 2013
Country: United States
First Name: Stick
Posts: 26,142
 
Default

Quote:
I would stay with dowels.
If good dowel joints aren’t the oldest joints ever made, loose ones must be...
dowels overtime, fail/loosen because of conflicting dimensional behavior between the dowel and wht they are inserted into...
humidity change alone can cause self-induced loosening...
w/o a drill press or a jig, it is tough to get right alignment......

Quote:
looks like you would be in for a full sheet of BB
so use VG hardwood like maple or ash for short end grain pieces or flat/rift sawn for long grain rips.....
Biagio and 1fizgig like this.

This would have been the week that I'd have finished chewing thru the restraints...
If only new layers hadn't been added....

Stick....
Forget the primal scream, just ROAR!!!
"SNORK Mountain Congressional Library and Taxidermy”
Stick486 is online now  
post #30 of 40 (permalink) Old 10-15-2019, 01:20 AM
Registered User
 
Join Date: Mar 2013
Country: South Africa
First Name: Biagio
Posts: 348
 
Send a message via Skype™ to Biagio
Default

@Stick486
I defer to your knowledge and experience. Always great to learn from you.
1fizgig likes this.
Biagio is offline  
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Router Forums forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in











Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome