Page 1 of 2 12 LastLast
Results 1 to 15 of 16

Thread: Glue clamping multi-sided boxes

  1. #1
    Join Date
    Dec 2012
    Location
    Bedford, NH
    Posts
    1,286

    Glue clamping multi-sided boxes

    Whenever I make 5,6 or 8-sided boxes I lay out the pieces on a length of blue masking tape while butting the pieces up against the fence on my table saw. I first lay down strips of clear shipping tape on the TS & on the fence to prevent the glue from contacting either the table or fence. Then, after applying glue to all the joints I "roll up" the pieces using the tape to fit all the pieces together & then place the box on the table to make sure the ends of all the pieces contact the table for good alignment. This works very well and all the joints appear to be tight when pulling tightly on the tape.

    However, I then use a strap clamp around all the pieces to securely clamp all the pieces together. Lately I've wondered if it is really necessary to use the strap clamp. Would the shipping tape actually be adequate to hold everything together tightly & securely enough for a good bond while the glue cures. So, I'm wondering what you guys do: with or without the strap clamp, or do you use a different method?
    Thoughts entering one's mind need not exit one's mouth!
    As I age my memory fades .... and that's a load off my mind!

    "We Live In The Land Of The Free, Only Because Of The Brave"
    “The problems we face today are there because the people who work for a living are outnumbered by those who vote for a living."
    "
    Socialism is a philosophy of failure, the creed of ignorance, and the gospel of envy, its inherent virtue is the equal sharing of misery." Winston Churchill

  2. #2
    Join Date
    Feb 2003
    Location
    McKinney, TX
    Posts
    2,063
    I use only the clear packing tape because it gives a good stretch. It alone provides plenty of clamping pressure. I use it on 4 sided boxes and 4 piece mitered legs also
    Steve Jenkins, McKinney, TX. 469 742-9694
    Always use the word "impossible" with extreme caution

  3. #3
    Join Date
    Sep 2016
    Location
    Central Missouri, U.S.
    Posts
    1,263
    I only do four-sided boxes, but have never used a strap clamp in addition to the tape. Never had a glue joint fail yet.

  4. #4
    Join Date
    Apr 2016
    Location
    Tasmania
    Posts
    2,162
    If the tape closes your joints and you are happy with the glue line, you don't need to do any more. If you are not satisfied with your joint closure, strap clamp as well. The idea is to do what works. There is no right or wrong in this. Cheers

  5. #5
    As stated earlier, do what works for you. IMO the value of clamp pressure on a glued joint may depend on the quality of the joint itself.

    It's not clear how large your boxes are, how thick the stock is, and what they are used for. My comment is based on considerable experience with segmented turning blanks involving 8, 12 and (sometimes) 24 sides, up to 12" diameter. I have also done a few 45 deg miter joints on larger objects. The segmented turning blanks usually get turned to a wall thickness of 3/16" - 1/4". In the process of turning (and then in use) these mugs, bowls, lamps, etc.are subjected to strain.

    I use the same assembly method that you describe, with blue painters tape. (I may switch to packing tape based on earlier comments.) I think the quality of the mating surfaces is the most important. If the walls of the blank are not parallel (as with a cone shape) it is very difficult to get any clamp pressure on the joints. I get excellent adhesion from rubbed joints with no clamping if the mating surfaces are very good. However, if the blank is cylindrical I clamp the piece very tightly with band clamps. (Why not?) I tend to "prime" end-grain joints by letting the adhesive set on them a minute.

    Doug

  6. #6
    Join Date
    Feb 2003
    Location
    McKean, PA
    Posts
    15,595
    Blog Entries
    1
    I use painters tape to aid in assembly and then use a strap clamp or two to pull the joints tight.

    Just remember that in multi-sided boxes, the joints are end grain joints and you need to apply glue to both sides of the joint to insure there is no glue starvation.
    Lee Schierer
    USNA '71
    Go Navy!

    My advice, comments and suggestions are free, but it costs money to run the site. If you found something of value here please give a little something back by becoming a contributor! Please Contribute

  7. #7
    Join Date
    Dec 2012
    Location
    Bedford, NH
    Posts
    1,286
    Thank you all for your comments, they were very helpful. Some of my own:

    1. The box is approximately 8"W x 12"L x 5 1/2"H made of Poplar with 1/2" walls.
    2. I did use the blue masking tape to "layout" & roll the pieces together; they did roll nicely as in previous projects.
    3. I will try the packing tape in the future as suggested above. I like the "extra stretch" mentioned as that should provide an even tighter joint.
    4. My thoughts have always been to make the joint as tight as possible to ensure a solid joint glue-up. However, lately I've been wondering if the strap clamps are really necessary as they could distort the shape from their 22 1/2 °, 45° angles. I do tend to overdo things for the sake of sturdiness. So, this leaves me wondering if the joint appears to be aligned well and closed tightly just from the tape wrap do they need to be "compressed" by the strap clamp to ensure a good quality joint? Does the glue (Titebond III) cure & hold properly when just in contact with the mating surface, or does there need to be a very tight interface?
    5. The joints on this box are in fact mitered end joints. I was originally thinking of making splined miter joints, but then thought that with the 1/2" walls, plus since it's a jewelry box there's very little stress on the joints, so I passed on the splines. This also reduced the amount of time & effort involved.


    I have completed the box and used Minwax Pre-stain & Conditioner to minimize blotching; applied 2 coats of a 3/1 blend of Minwax Sedona Red 222 / Minwax Red Mahogany stains (daughter wanted a "reddish" stain); then used Minwax Clear Gloss Polyurethane sprayed from a rattle can as a top coat. The can instructions for applying the polyurethane is to apply the 2nd coat within 2 hours, if cannot, wait 72 hours, then lightly sand before applying the next coat. I followed these instructions & the result was lousy. I didn't sand in between coats because it was still tacky & would have smeared if I did. So, thinking the directions were correct I followed them. This was a mistake! A really rough finish resulted - nubs galore. I think the gas in the rattle can created the problem along with not being able to sand within the 2 hour limit. What a way to spoil a project. Lesson learned!

    Not wanting to continue with the spray method I lightly sanded the entire box, lid & tray & applied Minwax Clear Gloss Polyurethane, this time from a can & brushed on a light coat, then repeated this the way I normally apply polyurethane. This time around it was much better, although I'm having 2nd thoughts now on the gloss thinking a satin finish might look better. This is a birthday gift for my daughter, so I'll wait to see how she reacts. There are now six (6) coats of polyurethane (4/spray & 2/brush) & it has a nice deep, rich appearance. I am surprised at how differently the stain took on the Poplar, quite a contrast, but it is what it is. If she prefers the satin I think I can apply the satin over the gloss if I lightly sand the gloss.

    Can satin be applied over gloss , or am I doomed?


    Frankly, I'm really disappointed in the way the stain took, especially after treating it with pre-stain conditioner - far more radical blotching than expected. I'm also not pleased with the polyurethane clear gloss finish. In places it looks like there is simply too much of it. If I had to do it over again I would have used the satin finish & would not use the spray application. Its 2-hr limit on re-coat doesn't work well at all.

    I'm going to apply a wine colored velvet to the inside walls & floor of both the box & tray; yet to be done. This will hide the blotching along the inside walls of the tray. I'm also installing a nice brass chain support for the lid as I preferred a long hinge rather than (2) short hinges, but a long locking hinge wasn't available at Rockler. Finally, I just received the ring pad to install in one of the tray compartments.

    Your comments & critique are appreciated as usual.
    Attached Images Attached Images
    Thoughts entering one's mind need not exit one's mouth!
    As I age my memory fades .... and that's a load off my mind!

    "We Live In The Land Of The Free, Only Because Of The Brave"
    “The problems we face today are there because the people who work for a living are outnumbered by those who vote for a living."
    "
    Socialism is a philosophy of failure, the creed of ignorance, and the gospel of envy, its inherent virtue is the equal sharing of misery." Winston Churchill

  8. #8
    Join Date
    Feb 2003
    Location
    McKean, PA
    Posts
    15,595
    Blog Entries
    1
    I usually use semi-gloss on projects rather than gloss or satin. I don't care for how gloss and satin turn out. As far as putting satin over your gloss finish, since it is polyurethane you will need to sand it lightly to get adhesion between the layers, which I would think would get your finish where you want it. Not much you can do about the stain blotching at this point. It happens with poplar and maple. Sometimes you can sand the light areas with one grit rougher than the dark areas to get them to take a bit more stain. On tops and front faces, it is helps to grain match as much as you can and use pieces from adjacent sections of the same board.
    Lee Schierer
    USNA '71
    Go Navy!

    My advice, comments and suggestions are free, but it costs money to run the site. If you found something of value here please give a little something back by becoming a contributor! Please Contribute

  9. #9
    Al,

    The box looks nice. I doubt that anyone will notice the "blotching." It does not look blotchy to me in the photos. It looks like variation in wood grain. Yes, you can apply satin over gloss. I don't usually use satin varnish, but when I do, I apply gloss for my base coats and then let the last coat be satin. If the joints are tight and strong you have answered your previous question. I have used transverse splines (false box joints) on mitered boxes. They add strength and a bit of character.

    Your four coats of varnish are really two coats, since the spray coats are not very thick. Still, I'll bet that you can gently rub out the finish with 600 grit wet/dry sandpaper. That will give you a smooth (no nibs) finish that feels nice to the hand. Just be careful. Because you used colored varnish you must remove it evenly or you will get light colored areas that won't look very nice. So, just sand lightly until it's smooth and fairly even. Use a sanding block and be careful at the corners!!! Also, it will give you a duller finish that you may want, which you can probably bring back up with 0000 steel wool and a good paste wax. Some people would skip the sandpaper and go to 0000 steel wool, but in my experience that does not remove surface nibs.

    Doug

  10. #10
    Have had great success on a couple of odd-shaped projects with the binding tape from Lee Valley, the 3M one. Strong and doesnt leave hard to remove residue like masking tape. I think they say guitar makers use those tapes.

    Simon

  11. #11
    Join Date
    Dec 2009
    Location
    El Dorado Hills, CA
    Posts
    1,311
    Quote Originally Posted by Al Launier View Post
    Can satin be applied over gloss , or am I doomed?
    I think this is the preferred solution. Satin and semi-gloss add something to make them slightly cloudy. It is best to use gloss for everything except the final step.

    Steve

  12. #12
    Join Date
    Sep 2016
    Location
    Central Missouri, U.S.
    Posts
    1,263
    Quote Originally Posted by Simon MacGowen View Post
    Have had great success on a couple of odd-shaped projects with the binding tape from Lee Valley, the 3M one. Strong and doesnt leave hard to remove residue like masking tape. I think they say guitar makers use those tapes.

    Simon
    Yup, this is the one I use:

    http://www.leevalley.com/us/wood/pag...at=1,110,43466

    Also available through Amazon.

  13. #13
    Join Date
    Feb 2008
    Location
    E TN, near Knoxville
    Posts
    12,298
    Quote Originally Posted by Al Launier View Post
    Can satin be applied over gloss , or am I doomed?
    I don't know about poly, but when spraying acrylic recently the instructions for the matte said if using multiple coats to use the gloss version for all but the final coat to avoid making the finish look "cloudy."

    BTW, I couldn't help myself - when I read the title about clamping multi-sided boxes I thought "as compared to what, single-sided boxes?" (I knew what you meant, of course!)

    I have used the tape method before. However, I started using a different masking tape a few years ago which I like better than blue painters tape for almost everything, sticks better than the blue: 3M Masking Tape for Hard-to-Stick Surfaces - https://www.amazon.com/gp/product/B00004Z4AY They advertise that it will stick to brick, concrete, rough wood, etc. and it does. Leaves no residue. This is not the green tape I saw in the paint isle at Home Depot.

    JKJ

  14. #14
    Join Date
    Feb 2008
    Location
    Southwestern Penna.
    Posts
    329
    I guess I'm the only one still using large rubber bands. No need for tape no residue, reusable, you can increase or decrease the pressure by doubling.

  15. #15
    Join Date
    Dec 2012
    Location
    Bedford, NH
    Posts
    1,286
    For clarification the lid is actually a single piece, from a wide board. In the past I've used multiple pieces, as Lee has suggested, for lids & walls, alternating them to minimize warpage & do try to align the grain if I can. In this case, the wood was from different pieces of lumber. Lesson learned here is to be more selective of the wood that will be stained.

    As far as the satin is concerned, I'm going to wait until my daughter comes home to get her reaction & preference. My daughter much prefers things natural rather than uniform as we tend to do things. She sees beauty in and loves the randomness & variety offered by Mother Nature. She really wanted to see the grain show so I glossed it, as well as flaws I might make, rather than me try to fix up my mistake. Lucky me!

    I also prefer to stain & see the grain, but I need to improve a lot before I get to where I'm satisfied. My wife prefers paint, so I won't have to be so concerned as I'm now about to paint her jewelry box which is the same construction. Lucky me again!

    I'm convinced that using tape or rubber will be adequate to properly glue a box. That makes things easier. I'll be getting the 3M tapes noted above. I was previously going to use the packing tape, but am now concerned about possible residue, although I do like the strength & stretch, perhaps I'll test it out.

    So now my daughter's J-box is completed, now to finish my wife's.

    PS: Applying the adhesive-backed felt to the bottom was far more difficult than expected. The adhesive is much more sticky than the adhesive on the velvet. Just barely touching it would cause it to stick & move out of place, or fold onto itself. Normally I would position a corner of the velvet to the wood & then slowly peel the film away while unrolling it onto the wood. If I screw up I can pull it off & re-do it. Not so with the felt, it's a disaster waiting to happen. As it turned out I wasn't able to match the edge of the felt with the base, so I had to trim the felt to make it look like an intentional margin. Oh well, live & learn.

    Thanks again for all your comments & suggestions, they were helpful, especially going forward.
    Attached Images Attached Images
    Thoughts entering one's mind need not exit one's mouth!
    As I age my memory fades .... and that's a load off my mind!

    "We Live In The Land Of The Free, Only Because Of The Brave"
    “The problems we face today are there because the people who work for a living are outnumbered by those who vote for a living."
    "
    Socialism is a philosophy of failure, the creed of ignorance, and the gospel of envy, its inherent virtue is the equal sharing of misery." Winston Churchill

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •