Cutting long tapers, with bevels

[Matt Calder]

Hi,

I am making, or rather, I am thinking about making, some veneered pillars. Imagine pyramids, very tall (~8') with narrow bases (~6" square), not pointy at the top but say (2" square). I would like to make the pillar using a torsion-box-like setup, with 3/4" plywood sides supported by interior cross pieces. This would seem to require very long tapers. The plywood pieces would be cut square. But the veneers (~1/4" thick hardwood) would be beveled to 45 degrees so as to enclose the inner plywood neatly.

I searched the forum and it seems the most applicable suggestion is to adhere (using double stick tape say) the to-be-cut piece to a plywood straight-edge / sled at the desired angle. The plywood sled would then run against the table saw fence.

I can almost see this working, but have two concerns. One, what is the best way to keep the plywood sled flat? Do you think it would work (or be necessary) to build a narrow torsion box along the length of the fence side of the sled? Two, how repeatable will cuts be under the most optimistic sled construction scenarios? There are to be six pillars, as nearly identical as possible.

Of course, I am open to other suggestions to accomplish the ultimate goal of repeatable, long, beveled tapers.

Matt

[Ben Grunow]

I made some columns that were tapered from 12" to 9" over 8' and my solution was to purchase a festool cs for the job and it WAY more than paid for itself on one job. Place the material to be cut ona flat bench and cut to your layout line. No taper jig and extra nail holes and much faster and easier than feeding all those odd shapes over the TS.

It is expensive but I and many others use the tool for cutting sheet goods all the time.

You could also cut with a standard cs ona homemade sled. I would recommend either over the ts as the material is too flexible.

[Matt Calder]

Ben,

Do you mean a the circular saw and guiderail system? I have a similar setup (shopmade), but don't have a table long enough to cut on. Can one really get repeatability going this route? I wonder if you could give a bit more detail on how you set up the cuts? Thanks,

Matt

[Alan Turner]

Matt,
You don't need to be fancy to get a repeatable taper cut on a TS. Use a rip of MDF for your sled, run against the fence. Maybe about 10" wide for your application. You will need 4 different set ups for this operation, I think (if I understand what you want to do). One each for the first cut on the top/bottom, and for each of the sides, and then a second for each of the above to cut the second taper, on the opposite side. Mark out your pieces (only need to mark one of each). Set your top and bottom marks to the edge of the MDF rip, then screw on an angled fence (2" rip of plywood would be fine) tight to the fence side of the stock, and set a back block for registration. Put a couple of toggle clamps on the plywood fence to secure the stock to the sled during the cut. Make your first set of rip cuts. The, reset the plywood fence for the opposite side. By setting the stock per your marks at the exact edge of the mdf sled, this is your cut line as well. Note that mdf is 49" by 97", at least in our area, so you will have room for the rear registration block. I like to use mdf for sled material as it is flat, whereas plywood is not

At 8' in length, a second pair of hands would be helpful for accuracy and safety while running these. Shouldn't take more than an hour or so for all of these.

[Ben Grunow]

Yes Matt, I bought the Festool circular saw and a long guide (I think it is longer than 8') and the cuts are dead straight with no tear out and almost no saw marks.

The festool system is way more than a circular saw, search this site for info on them and you will see what I mean. Pricey but if your work is for a client you can buy the tool for the job and you will soon discover that it has a million uses.

I think a simple jig made from 2 strips of mdf (one 3" annd one 12" glued together with one edge aligned- first cut with the curcular saw set at 45 deg running base along narrow strip will trim the wider piece of mdf so the cut edge is supported where the teeth are coming up throught the wood being cut) would be enough to run a standard circular saw along and get fairly good results.

I am tired so this might not make sense. Let me know if I am insulting your intelligence or if I can help more.

Ben

[Ben Grunow]

I cut on piece of rigid foam insulation on some 2x4's and a 2'x8' of 3/4 plywood. Set the blade to cut the foam slightly.

[Michael Stanley]

You should try posting this in the EZ Smart forum. This sounds like the perfect application for the ez system.

[Matt Calder]

Hi,

It would seem there are two competing suggestions. One, to use a circular saw and to build/buy a jig to guide the saw through the cut. And two, to build a sled for the table saw. Thanks Ben for the point about beveling the part of the jig that the cut side holds against, that ought to help a lot in keeping things steady.

My instinct is to prefer the table saw solution, the thought of cutting at a 45 degree bevel, for 8 feet, and keeping it all straight with a circular saw seems iffy. But that rigid foam suggestion has swayed me, what a great idea for a temporary, sacrificial, bench top.

So, I think I'll attempt the circular saw way. If it turns out well, great. If not, nothing is lost, I'll just recycle the pieces into something along what Al describes. I'll update the post with the outcome.

Matt