Posts Tagged ‘Router (woodworking)’

I know… and mea culpa…    

I said here earlier that I would tell you about the progress on my table that I was making and I haven’t…    

But the good news is that I finally finished it!
Last Sunday I spent the last 6 hours or so, sanding the entire table and creating the table top decoration with the plunge router.
Also since Afzelia splinters easily, all edges needed to be smoothed (sanding, sanding and more sanding) to protect both the table and skin of its users.    

Now all that remains to do is put it outside and put it to the real first test on saturday (BBQ with some friends). We have secretly already used it this summer (june) but it missed the foot and finishing at that time.    

So here is some step by step information:    

Originally I tought of making the top about 40mm thick with an inlay of 20mm, but sometimes you have to take into account your wood measurements, so that you don’t waste too much material…    

The Afzelia came in beams of 670 mm thick, so I had those cut in 3; this, taking into account the saw thickness, left me with boards of just over 20mm each. Once they were planed (chafed?) and straightened that left me with a whole pile of 17mm boards. So 17mm became the standard measurement, making the top 34mm (2 glued together)    

The most difficult part of the entire table was creating the round borders for the tabletop.    

12th of a circle border piece

 

This is a 12th of a circle piece, which has a very narrow margin of error: once twelve are fitted together, the circle needs to be closed and it has to look like circle (no waves in the outline).    

Step 1: Draw one at full size
This immediately posed me with a problem since the radius is 900 mm and i don’t have a compass that size. A cord solved that and was accurate enough to give me the desired result. Since there are 12 pieces in a circle the ‘pie’ is 30°.  I didn’t trust my cord (and, I admit, I’m a perfectionist), so I didn’t want to read the length of the straight edge from the drawing, but wanted to calculate it. After some higher mathematics were applied, I got that figured out.    

Then I took a mdf board to create a first mould. After about half an hour of sanding I obtained a useable mould. Now since i needed to make 24 pieces using the miller (not sure that is the correct word) the mdf was not good enough as a guide (too soft). So I used the MDF mould to create the real mould from a piece of oak that was left from a previous venture.    

Tip: don’t make the same mistake I did, with making the mould too small. Leave extra wood where possible (of course not at the circle shape rim) so that you can easily fetch the board to the mould. The same of course applies for the boards. Make sure the 12th circle edge is roughly cut (so that you don’t need to take of too much material with the miller), but leave a reasonable portion to the sides or bottom to fix the mould (with screws).    

And if you did make the mistake, as I was glueing two pieces together, I made sure the screw holes were on the surfaces that were not going to be visible.    

Then problem number 2, cutting the edges at exactly 15°. Since my shop doesn’t have a computer driven saw, getting the angle correct is not easy. And again, since I was going to create a circle, the margin for error is very small. So set the saw to 15°, saw a piece of wood (trial) and measure it with an adjustable bevel. Again, I wasn’t convinced, so I actually sawed 12 pieces (of around 100mm length) and tried to create a circle. I’m sure I corrected it again with a least a 10th of a degree (I know, I know) and then finally cut the border pieces.    

Remark: Of course I glued them together first and sawed them after (avoiding a non perfect side edge)    

Tip: Since the edge is at a 15° angle, creating a tenon is very difficult. instead, I decided to make a mortise on each side and use a loose tenon.    

To be continued….

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