Timber Framers Guild Forums Tools Timber Engineering how to cut a large diameter arch in an big beam

I need to cut a large diameter arch in 8 oak 14" x 11" x 60" chunks (not sure beam is correct word - since it's not going to support anything).

Can't justify a mafel portable beam saw. Is it possible to rig up something to work on a large vertical band saw? Would the band saw need to be particularly fast? fyi: the oak logs haven't been cut yet (into the chunk). But they've been drying for over a year.

Any help or suggestions would be appreciated.

Hey Ruff! you got a sketch or picture of what you want to do. How you going to ruf em out of the logs ito your blank chunks? Depending on the tightness of the curve, you might not be able to use the Mafell beam cutter. But the Mafell portable bandsaw may cut 'em - depends on which way the curve goes in relation to the 14" or 11" dimension. I have Maf bandsaw for hire or for sale. You could take your oak chunks to someone's shop who has a stationary bandsaw. I have a 20" Davis & Wells 5hp which will cut 13" deep pieces, curved or straight. I'm in NY near CT. I bet you can find a Timber Framer w tools and shop close to you anywhere in CA or USA.
Why don't you fill in your profile, location etc. Tell us where you are and you'll prob get more response.
Check those oak logs for metal and paint/seal the ends. Stack 'em w air circulation and protectected from sun and rain.
Welcome to the forum, join the TF Guild, it's a great group.
Steve

We cut curves in timbers on stationary band saws frequently. as long as you have the throat height to take the piece of wood and good infeed and outfeed support, should be no problem. You will want a wider blade than you would use for 3/4" stuff. we use 3/4" wide bands on our smaller saw. We also have a 5 horse 30" throat bandsaw that will take anything we can shove through it.

I'm thinking another possible problem is that I don't have 3 phase power here. Do the converters work well? Any suggestions here?

Hey rwf, where you at?
I bought a new Heavy Duty Rotary Phase Converter from Cedarbeg Industries Minneapolis MN in 1988. It continues to work well. It runs on 220-230v single phase from the street (utility co.) and creates a third 120v leg to add to the 2 existing, and phases the power correctly for 3 ph motors. Closest NYSE&G 3ph transmission lines were miles away, so it made sense to purchase the PC. It's portable enough to take to job sites. They are sized to the max start-up HP of the first motor you start, then you can start your smaller 3ph motors one at a time after that.
For long term investment for stationary tools 3ph motors are best, prob once you need 4+ HP. Great convenience if your utility co has it on your street. Some Mafell TF tools are avail w 3ph motors.
Cedarberg had PCs for up to 100HP. Their 1989 ph# 612 888-3130 and 800 328-2279. I've never had to call them, don't know if AC has changed.
Steve

hey gable,

I've been wondering about horsepower. Is your 5 horse power adequate for your thickest cuts? What is your max cut thickness? What horse p do you recommend for your thickest cut?

RWF --

the 5 hp 3 phase motor doesn't even slow down when shoving an 8" thick oak timber through it (or 12" of pine).

we have a smaller bandsaw that we can push something 12" thick through and as long as you don't rush it, it will cut 12" fine. So feed rate is a big part of the equation.

i believe the mafell band saw will only cut up to 10". so a stationary jobber dobber is the way to go.