Wednesday, September 11, 2013

Preventing Glue Bleed-Through Veneer

This is the first time I've used sepele on a project. The problem I'm having is glue bleed through.The dark areas shown here are glue filling the wood's pores. This bleed-though is caused by the pores pulling the glue under the veneer through to the top surface. With oak, cherry and maple, I haven't had much of a problem. And usually if I see this issue, I can just sand it out. But I'm especially seeing this with sepele and sanding won't help.

Because I frequently use a water-based dye, I always use Titebond II for bonding veneer because it is water resistant and reduces delamination. Applying less glue may reduce bleed-through, but how much less before risking delamination?

I've even had issues after removing the veneer tape. After it look like it is completely removed, I'll dye the workpiece and then evidence of the tape adhesive reappears. I think it is the same issue as discussed before. The glue from the tape gets caught in the pores and you need to sand again and again. The problem, of course, is that you may sand all the way through the veneer.

I've been pleased with the results of sealing the back of the veneer to reduce glue bleed through by spraying one coat of Deft lacquer on the glue facing side of the veneer. On the top, I sprayed along the veneer seam before applying the veneer tape.

This stopped the veneer tape issues and considerably reduced the glue bleed-through, but some areas continued to appear. My second step is to soak up glue if it occurs. I lay sheets of brown masking paper between the veneer and the caul. This soaks up the glue to the veneer surface. When bleed-through is evident, light sanding is more successful because minimal glue remains in the pores.

With my glue bleed-through issues, I was originally thinking that this would be my last project with sepele. I'm please that this glue-up approach seems to be working so I can use sepele without worries next time.

Saturday, August 24, 2013

Art Deco Bookshelf

Art Deco Bookshelf
I made this bookshelf in an Art Deco style to hide my speakers behind the curved sheet metal. I've used a sepele veneer for the shelves and the sides. The challenge was creating the curved corners on the shelves using the small amount of mahogany I had for the edges. I've described making the large radii corners here and on the base I used a smaller diameter corner described here.

I've hidden the smaller speakers in the top right and left corners. In the base of the bookshelf I've hidden the large speaker. In order to prevent the whole assembly from vibrating from the music, I actually cut a hole in the base to allow the speaker to sit on the floor. It sounds good an now I can move my woodworking books out of the garage.

Saturday, July 27, 2013

Cutting a Recess In Shelves to Accommodate the Back

I'm building a bookshelf and the back doesn't extend the whole width of the shelf. This is mostly a note-to-self on how to cut a recessed area in the shelves to accommodate the back.

I want to use my router table for a clean cut on the veneered shelves. For the top and bottom shelves, I route a stopped rabbet cut.

For the middle shelf, do the same cut as the top shelf. Then using a straight bit with a bearing, cut the recessed area to the other side of the shelf. Square the corners if needed.

The whole process literally takes minutes.

Friday, July 26, 2013

Smaller Rounded Corners on Veneered Wood

Veneer applied to plywood has some challenges - what do you do about the edge which shows the stacked plys? You can either apply veneer edging or something a little bit thicker. For this project I wanted a 1" radius corner. On a previous post I had discussed how to glue a similar species wood on the edges and route rounded corners using a circle jig. For a radius smaller than the router base, you need a different solution.

Here I have glued strips of real mahogany to the sides of the plywood and want to round the corner. For the veneer, I'm using sapele which looks similar to mahogany, but is much cheaper. To create the small radius corner, I need to use a template and a straight router bit with a bearing.

My second requirement is to use my router table because when I clamp my template to the plywood, the clamps interfere with the router. The circle on the right side was made with a hole cutter used for drilling a house door to accommodate a handle. I then created the template by aligning the circle to the sides of the template workpiece. A ¼" metal dowel pin (shown on the template) secures the circle and allows me to replicate the curve on the template.

With the template created, I need to align its sides to the sides of my workpiece. Another ¼" hole is needed to prevent the template from rotating on the workpiece.  Two metal dowel pins are shown here sticking out. Now I can use the template to guide the router around the corner.

This technique works because the veneer will cover the holes. So now, I simply fill the holes and glue on the veneer.

Saturday, July 20, 2013

Art Deco Speaker Enclosures

I am building a bookshelf and want to incorporate into it the speakers that I use for my television. This is the design using Sketchup for enclosing the subwoofer speaker. I need a porous material to allow the sound to radiate so in this project I decided to use metal. This is my first venture into using this material.

My usual construction style is Arts & Crafts. I've decided to depart from that style for this project and try Art Deco using sapele veneer. I'm no expert, but this style uses metal, contrasting pigments, and curved profiles. The curves are especially challenging because I solely use veneer. The previous posts show my construction techniques for the veneered shelves. I have two enclosures that are a mirror of each other. The left enclosure holds the woofer and the right is empty. Since the woofer emits sound from the front and right side, the porous metal needs to be on these sides.

The left side of the enclosure is a slightly curved surface using sepele veneer. It has been bonded to a piece of 1/8" MDF. The curve is created by forcing the MDF into routed curved slots in the top and bottom pieces.

For the porous metal, I've used sheet aluminum that is 1/32" thick. Creases are very noticeable, so cutting it was a concern. I've quite successfully used my tablesaw with an old crosscut blade. I've painted and used a water finish before inserting the metal. The blue tape protects the wood from scratches when I install the metal sheet.

The curve in the metal sheet is formed by bending it around an aerosol paint can. The cutouts in the back accommodate the speaker wires and power connection.

Curving the surface of the sheet creates a fair amount of vertical strength, but the rest of the enclosure is intended for vertical support and the ¼" plywood inserts resist racking in the front-to-back and side-to-side directions.

This enclosure is on a shelf which is the bottom of the bookshelf. A square hole in this shelf will allow the woofer to sit on the floor. I'm hoping this will allow the bass sound to still radiate into the floor and prevent unwanted vibration into the bookshelf.