Cutting curves and profiles in thick and heavy stock

[Patrick Kane]

Looking for the best approach for cutting ogee profiles in exposed rafter tails and an exposed ridge beam. The rafters are 3" by 6" and the beam is 6"x6". They are 14' long and pretty wet still, so they are beyond heavy. In other words, bringing them into my small shop and cutting them on the 20" laguna bandsaw is impossible/impractical. I think i have 30 ends to cut in total. The ideal solution looks to be Mafell's bandsaw, but that is a pricey acquisition for a small job, and i cant seem to find a cheaper alternative. My first thought was a jigsaw, and while it looks like i can get a 9" blade from bosch, i think this would be dreadfully slow. My 20v dewalt jigsaw has always been a little disappointing in anything but thin material. I think on a 6" cut, im going to have horrendous drift. Has anyone ever flipped a 10-12" bandsaw upside down and used it as a portable tool? Im not sure those models have a 6" throat, however, but they dont look like they are too heavy. Another solution is i avoid curves in the profile altogether and just bevel the ends, or a long taper with a shoulder cut. This project has been very time consuming for a simple shed and im at the point where i want to rush things along, but this is one of the few details that will actually show.

[Andy D Jones]

Could you fashion a template, and cut the profile with a router?

-- Andy - Arlington TX

[Paul F Franklin]

I recall an episode of This Old house where they supported the beam and used a regular bandsaw that was mounted on casters to cut the beam ends. They moved the saw, not the beam. Not sure I would want to do that with a 20" saw, but a smaller lighter saw would be manageable. With this method, you are not supporting the weight of either the saw or the beam, so you can concentrate on guiding the cut.

Another option would be a portaband, at least for the 3" thick pieces. Don't know if there are portabands that can do 6". I have the harbor freight portaband and it works pretty well for a $120 tool.

[Prashun Patel]

I like the first or third pics, personally.

However, if I had to do the curves, I'd probably get a longer router bit and template route the rafters with a plunge router.

The end of the beam appears to be a cove. You could use a large hole saw for that. You'll have to gang a sacrificial 6x6 so the bit can register. I would start the hole, then drill relief holes just inside the kerf, and then complete the cut with the hole saw. The reliefs will preserve the life of the saw teeth. Go slow and clear out buildup as you go.

If you can find a Ridgid spindle sander, that would make quick work of cleaning up the coves and ogees. It's portable enough to take onsite. I think it has a 6" stroke, but if not, you can flip your beam and sand them in 2 passes.

[Phillip Mitchell]

Without a Mafell portable bandsaw available, I would choose to alter the design to something I could do with a circular saw like a long clipped corner / seat cut on the ends of the rafters / plates. Doesn’t have to be a 45* angle. It can be a longer cut / shallower angle.

I generally dislike the more ornate, Anglo / European scroll type timber work personally and prefer a cleaner, more Asian influenced design aesthetic, but that’s just me.

The Mafell bandsaw is an amazing tool and can be used for more than just scroll type work. I’ve used it in timber framing for cutting notches and tenons that weren’t angled and in a lot of one off situations that you might not think of using it for, but it is as accurate cutting as any other tool out there. It is quite expensive though and probably not worth the admission price unless you’re using it often and professionally.

[brent stanley]

I haven't gone the expensive Mafell route yet so I do them with a template guided, long upcut spiral bit. You should be able to do the rafters with a long jigsaw close enough then finish with the router. Don't cut the rest of your joinery till you're done so you can shift a 1/4" and redo the end if something goes wrong. I would do the same with the 6x6 except skip the jigsaw step and do repetitive cuts with your largest skilsaw, on the end down to the line. Then after a pass on each side with the router, and knocking away the waste, you'll have to chisel by hand the bit in the middle with a rounded chisel. Find a cylinder with the same radius as the curve, coat it in 100grit paper and use it as a formed sanding block to finish up. Don't worry too much about the cosmetics of the end because it will crack and split in short order!

[Jamie Buxton]

You could cut the 3x6 with a portaband. These are handheld band saws intended to cut piping and such. You might find one with a useful table on it, or you might want to jig one on to it. The Harbor Freight class of these costs less than $200.

For the 6x6, you might consider a bow saw or a frame saw. These are muscle-powered saws, but you're cutting green soft lumber, and a sharp blade will make quick work. Examples: https://www.fine-tools.com/gestell.html On that page, there's even narrow blades for cutting curves.

[Doug Garson]

I posted a similar question a few years ago on another forum and got many of the same recommendations. I ended up using my Bosch jigsaw with a 6" blade to cut two 6" x 8" Fir beams and about six 2" x 8" cedar joists/ledger boards. I made a template, marked the cut and cut it freehand. I had some runout on the Fir beams, (little or none on the cedar joists/ledger boards) which I corrected with a belt sander. In hindsight I could have marked both sides with the template and cleaned up most or all of the runout on the second side using the jigsaw. You would probably get more precise results if you rough cut with a jigsaw and cleaned it up with a template and router from both sides as I'm not sure you can get a 6" long pattern bit.

[John C Bush]

We built a pergola using 16 full 2" x 6" WRC "rafters?" and 2" x 10" "beams?". I made a template for the ogee, traced a line, rough cut with a jigsaw, and used the template for the finished edge. The jigsaw did well for the rough cuts but the longer blades can flex off line and don't give a good finished look(in my hands anyway!!) I used a top bearing bit to index the template and extended the shank as needed and indexed the guide bearing to the finished milled surface. 1/4" ply for the template and #2 finish nails to hold in place. Didn't take long and the finished edges look very nice. The 6"ers can be done the same way working from both sides. I already had a 2" pattern bit and I imagine there are longer bits available if needed. Good luck,JCB

[brent stanley]

I posted a similar question a few years ago on another forum and got many of the same recommendations. I ended up using my Bosch jigsaw with a 6" blade to cut two 6" x 8" Fir beams and about six 2" x 8" cedar joists/ledger boards. I made a template, marked the cut and cut it freehand. I had some runout on the Fir beams, (little or none on the cedar joists/ledger boards) which I corrected with a belt sander. In hindsight I could have marked both sides with the template and cleaned up most or all of the runout on the second side using the jigsaw. You would probably get more precise results if you rough cut with a jigsaw and cleaned it up with a template and router from both sides as I'm not sure you can get a 6" long pattern bit.

That's good to know a 6" long blade in a jigsaw will work that well, thanks. I was suggesting essentially your last sentence but use as long a bit in the router as you can find from each side, and fix up whatever you don't get with a chisel followed by sanding.

[Patrick Kane]

Thanks for the replies. Sounds like the jigsaw might not be a waste of time after all. The comments about keeping it simple with straight lines hit home. I can make a lot of the cuts with the tracksaw that would require minimal/no cleanup afterwards. The jigsaw plus template routing from each side will be a 15 minute process, which is an 8 hour day of just doing profiles.

[Christopher Giles]

I would re-imagine the beam in two parts. The end can be made just longer than the ogee profile, and be built with the right joinery (sort of a bridle joint for example) to be connected to the rest of the rafter after it has been safely and accurately cut on your bandsaw in your shop. This is the only way I would proceed with this situation.

[Edwin Santos]

You could cut the 3x6 with a portaband. These are handheld band saws intended to cut piping and such. You might find one with a useful table on it, or you might want to jig one on to it. The Harbor Freight class of these costs less than $200.

Yes, the job you are describing is a common every day job in the Southwest. The photo below is an example, cut with a Milwaukee portable band saw on site. DeWalt and others make them too. Should be about $250 at Home Depot.

If you can get consistent results with a jigsaw without deflection problems, you're a better man than I, and definitely more patient.

corbel.jpeg

[mike stenson]

Yes, the job you are describing is a common every day job in the Southwest. The photo below is an example, cut with a Milwaukee portable band saw on site. DeWalt and others make them too. Should be about $250 at Home Depot.

If you can get consistent results with a jigsaw without deflection problems, you're a better man than I, and definitely more patient.

corbel.jpeg

This is what I'd do (the portaband), and yes.. pretty much every beam in my house/porch has this detail (corbels)..

[Bill Dufour]

I would also suggest a Milwaukee portaband saw. The fpm is a little slow for wood but a portable bandsaw will be hard to find. I will keep searching and give you the name to search for later. I have seen movies of them used to saw ships timbers.
Bill D