Custom Log Lathe Help

logboy · August 08, 2011, 11:50:01 AM

I'm wondering if there are some hobbyist mechanical engineers out there who can help me out with this. I couple years ago I built a makeshift lathe setup to use with my Lucas Mill. The main purpose is for turning cedar logs into 12-15" diameter logs for log rolling competitions. It consists of two steel stands connected via 4 x 4s to keep things aligned. The logs are mounted via 3/8" lags through a 1/4" plate welded to a 1" steel shaft. The shaft is mounted on a couple pillow blocks.

On the saw end I attached a couple gears and #35 chain and a handle for turning the log manually. My "lock" is terrible. Its a cobbled together piece of gear attached to a toggle clamp that simply pushes against the chain. It barely works and seriously slows me down. It takes a tiny amount of force to spin it when locked.

The lathe actually works surprisingly well for its simplicity. Unfortunately I keep finding myself turning larger and larger logs for which it was never intended including a couple large pines for a log home builder. In the future I may build a real lathe with a true head/tail stock and full hydraulics. For now this will have to work. I'm planning on doubling the size of the shaft to 2". The mounting plate will be at least 1/2" thick up from 1/4". I'm thinking about milling a 2" long point on the end of the shaft and extending it through the mounting plate to act as a center to carry some of the weight and take some load off the lag screws. Is there a better way to do this?

I'm open to ideas. Overall the lathe works pretty good for as much as I use it. But it needs some improvements.

Most importantly, I need a lock that actually works so I can mill safely without having to worry about the log spinning when I'm trying to mill the log down to size. The gear chain lock doesn't cut it.

Ideas?

mad murdock · August 08, 2011, 12:10:54 PM

interesting contraption you have built! You definitely need your head/tail mounted to a frame heavy enough to put Hydraulics on, then you could use the same hydraulics as a brake. for now, you could mount a simple caliper brake system to the hub that has the chain on it, and use that as a stop/lock. You can buy brake discs and calipers from several sources, check out what is available from places that sell kit/components for go-carts, that would be cheap. If you need larger, then look at motorcycle junk yards for bits from an old bike you could adapt for your application.
fwiw.

Hilltop366 · August 08, 2011, 12:39:21 PM

Another idea would be a pulley next to the large sprocket with a piece a belt fastened to the frame on one end and on a spring loaded leaver on the other, pull leaver to release tension and allow log to turn, release leaver and spring pulls belt tight to hold log in place.

It may work.

logboy · August 08, 2011, 12:47:56 PM

Old brake parts are no problem. Thats my old mans mechanic shop in the background. I still might end up doing hydraulics just on the stand. I think I can get away with a small hydraulic motor and a little 5 hp motor for the pump. That would give me the lock I need and the rotation for spinning the log on the final cut. My arm and hand are tired of spinning logs by hand for 15 minutes at a time.