Tuesday, July 31, 2018

Started On The Sawmill Power Head

So got back in the shop this afternoon. After playing with and sketching a lot of ideas I am ready to start on the power head. First job is to get the proper spacing on the head slides. Measurements need to be quite precise here. I first installed shims on the inside of the slides to center them on the uprights then locked them in place. Then I cut two lengths of 2" X 3/16" tubing to span the distance between the slides. I first cut them a little large and then took a pass with the grinder and tried them out, until I got a tight fit. Next I made the sliding locks for the blade guides these will be installed on the bottom stretcher. The top stretcher, I first installed the two lifting eye bolts and drilled it to accept the motor mounting plate later. Here are a few pictures.

Here the first stretcher is welded in place. The two black sliders will receive the blade guides. If you expand and look carefully at the top and bottom of the sliders you can see the shims to prevent binding on the frame.

Here is a close picture of the blade guide slider locks on the backside.

Here the top stretcher is welded in place. The two lifting eyes are in place, and it has been drilled 3/8" to bolt the motor base to. I have a aluminum 12" X 24" X 1" plate that has been taking up space for far to long. It will get bolted to the underside of this top stretcher.

So I removed the shims and lowered and raised the head slide. Great no hang-ups moved freely through it's full range of motion. Here near the top of it's travel.

So now that my clearances have been established, I will remove the head frame tomorrow, finish the welding and continue with the head build on the bench.

Sunday, July 29, 2018

Head Frame Sockets Welded In.

So short day today, my old body is starting to feel all this physical work, sure sleeping good though lately, ha ha.

I started this morning removing the head frame, also removed the log hoist and the carriage. Rolled up my mobile hoist and flipped the sawmill frame on its side and welded in the first head frame socket. Before flipping the trailer I measured and located the socket locations and tack welded the top/side edge, after flipping, the bottom edge got one heavy pass, and the two long sides got two heavy passes, each side. Lowered the frame and flipped it on the opposite side to weld in the second socket, with the same procedure. Lowered the trailer frame back to the floor, checked my measurements, looks good, reinstalled the head frame and tightened down the locks.

I outdid myself the whole assembly feels like one solid unit, if I didn't know the head frame was removable, I would think the whole unit was one welded assembly. Here are a few pictures.

Saturday, July 28, 2018

Head (Arch) Frame Welded Up

I prefer Head but Arch is used for conventional band sawmills, this one is stationary so I think Head is more suitable.

So I got back in the shop after supper and got carried away. Welded up the head frame. After welding up the jog in the bottom, sides, I spent well over an hr. squaring up and clamping the frame. I checked and rechecked the frame for squareness and adjusted the height of the corners many times to get the frame flat and level. Eventually I struck an arc and tacked the corners, stopped and rechecked my measurements, still good, completed welding the corners. Sorry I was so engrossed I forgot to take setup pictures.

After welding I temporarily clamped the receiver sockets over the axle hangers for support and installed the frame to see how it fits up. It was a snug fit but eventually slid right in. Here are some pictures.

The jogs in the side frame give me the right measurement between uprights for a 149" blade with lots of tension adjustment. They also prevent the slides from dropping the blade into the carriage. The closest the blade can come to the carriage is 1/2" , just enough to clear the rear dogs in the lowest setting.

Preparing Locks For Head Frame

So I got a few hrs. in the shop after lunch. The head slides and head frame sockets needed to be drilled 9/16" and nuts welded on to accept 1/2" bolts for locks. The frame sockets need bottom plates welded on to limit the frame insertion into the sockets. In the first picture the parts are drilled ready for the welding.

Here all the 1/2" nuts are welded on and the bottom plates are welded on the frame sockets. The bottom plates are drilled to prevent rain from filling the sockets with water. These sockets will be welded to the trailer frame. The whole head assembly and frame will insert into these sockets and locked in place with the 4 - 1/2" bolts. This also means of course that it can be removed if I need to work on it or if I decide to change something. And for a different take, if I need to haul something long and heavy, I can remove the head frame and carriage and use just the trailer and hoist to load and haul whatever item has peaked my pack rat interest, ha, ha.

The two longer pieces are the frame slides, the wheels, bearings, drive, engine, and many operating assemblies will all be attached to these slides. When making a cut it is important that this assembly is locked to the head frame to prevent any shifting which would effect the quality of the cut. To make this more convenient I would like to set up a linkage that would allow both locks to be tightened from the operating position.  Something like this, we'll see when we get to it.

If I get ambitious later, maybe I'll get started welding up the head frame.

Friday, July 27, 2018

Cut The Main Parts For The Mill Head Frame.

So I spent the afternoon juggling measurements until I got the head frame sketched out to something that I liked. After supper, I couldn't resist, grabbed my sketch and headed out to the shop. I managed to get all the main pieces cut. I thought I was going to lose my 14" abrasive chop saw, half way through but it held on. It started to spark real bad, but eventually the brushes wore in and it settled down. Good thing, I have already installed the spare set of brushes that it comes with. These were on sale, so cheap ($99) at Princess Auto, I got two. That was at least 15 years ago and I am still on my first one. Sometimes you get lucky with these cheap imports.

So anyway here is a picture of the main frame members. The frame is 2 1/2" X 3/16" heavy wall tubing. The sockets, the frame fits into, and the head slides are 3" X 3/16" heavy wall tubing. There are a number of operations I need to do on some of the pieces before I can weld the frame together. Tomorrow.

Thursday, July 26, 2018

Cleaned Up Tilt And Tension Assembly

So got in the shop this afternoon and finished the drive shaft. The picture isn't great but you can see I added the pulley side keyway, a little better than the first keyway. I'd like to blame my cheap, sloppy, import machines, but the truth is I am a relative newbie at machinist work, I have read stacks of info on the subject, but nothing works as well as hands on work. I learn something new every time I machine something.

So the next item is the tilt and tension assembly. This will require some modification but I'm going to try to use most of it. I first dismantled and cleaned up the parts with wire wheel and WD-40. Surprisingly the bearings were still good, tight and still lubricated. The sliding tension adjustment was seized with rust but it cleaned up ok.

So to get the right fit I will need to reverse the tension adjustment slide on the base. Anyone familiar with older Delta bandsaws will see that that is how I reassembled it here. This will require modifications to the tension screw and the tilt screw. I will not be using a spring for tension, as Wood-Mizer found out early on that these mills run better without them. Thats why the spring and cap you see in the picture did not get cleaned.

Here is the reverse side. This is the wheel for this assembly, I have yet to clean up the wheels. As I mentioned before the tires are like new. They must have changed them shortly before taking the saw out of commission. If they had changed the bottom bearings instead, it probably would have run much longer.

So this gives me a good idea of the measurements I will require for building the head assembly. I'll get started on that probably Saturday.

Wednesday, July 25, 2018

Prepared The Drive Wheel Assembly.

So before I can start building the head assembly I need a few critical measurements. I have a stack of blades that I got with the old scraped Delta and General band saws that I mentioned in previous posts. It would be nice if I could use them up, aside from surface rust some of them look new and others have been resharpened.

I decided to go with the Delta wheels and assemblies. If I blow up the aluminum wheels, I have the heavy cast iron General wheels to fall back on. So I spent yesterday dismantling the wheel assemblies, to see what I can adapt to my needs. The tension and tilt idler wheel assembly will require much modification, but I think I can use most of it, I,ll work on that tomorrow.

For the drive wheel assembly the only thing I can use is the band wheel itself. The casting is to heavy and odd shaped to use. Both bearings were shot, dry, and noise. I considered the shaft but it was a little long and would have been harder to fit odd size bearings too, without a lot of turning.

So after thinking about it for a while, I made a trip into town this morning and picked up two 1 1/4" pillow block bearings and a 3' length of 1 1/4" chrome steel shafting. In the picture below I have already turned the 11" shaft I cut from the 3' piece and trying the bearings on it.

Here I turned the band wheel side to 1" to accept the Delta wheel. The rest of the shaft will remain 1 1/4".

After turning I cut a 1/4" keyway, and drilled and tapped the end to accept a 3/8" X 1" bolt, lock, and heavy washer. The other end still needs a keyway, tomorrow.

Here is a rough assembly, The drive pulley is 14", the band saw wheel is 20".

Monday, July 23, 2018

Speeded Up Carriage Feed

So back to the carriage feed, running on top of three raps of cable started to sound dodgy, pretty quick, so what to do. I checked my military storage boxes, where I keep different offcuts of pipe and bar stock. I found a short piece of 1 1/2" schedule 80 pipe. the inside diameter was a little larger than the winch drum diameter and outside diameter was almost 2". Should work, I cut a piece to match the length of the drum, and then cut it lengthwise in half. I drilled one to take a 1/4" thread for a set screw to lock the sleeve on the drum.

Here's the drum before adding the sleeve.

Here the sleeve in place. The saw kerf when I cut the pipe in half made for a very tight fit. It took two vice grips and a lot of pressure to bring the two halves together to weld. I run a light rod, at light heat, so I didn't damage the aluminum drum, when welding the halves together. Filed the welds smooth and drilled a dimple in the drum, through the set screw hole, and tightened in a set screw to insure the new sleeve doesn't turn on the drum. Old diameter 1 1/4", new diameter 1 7/8".

So time to try it again. This time the feed worked out to a little over 14 fpm. Awesome, I could get more out of it , but I don't see any need to work the engine any harder. If I am not careful I could bury myself in lumber pretty quick, if I can slice a board off an 8' log in 40 seconds. If I want to go faster on small diameter logs, I can disengage the winch and feed by hand as fast as the blade will take it.

Did a walk around the frame. A few of the cable clearances were close or touching some of the cross members like the front and back of the carriage when it was at the ends of its travel. Ground clearance notches where required.

Here is a picture looking down on the mill.

Sunday, July 22, 2018

The Carriage Is Under Power

So I started out this morning preparing the hardware for the carriage feed. Here is all the hardware ready to weld and install.

The carriage stops welded in place. The cable pulleys also welded and installed.

The winch mounting plate welded in place and the winch bolted to the plate. The winch is an inexpensive 1500 lb. ATV winch. Canadian Tire had a sale on them a number of years ago, I got 4 of them for $40 each (packrat, ha, ha).

Here you can see the connection to the carriage and the end frame pulleys.

The springs serve three purposes, first they keep the raps on the winch drum tight to prevent slipping, second they provide a shock absorber, for the winch, if you hit the stops hard, and thirdly they are also a shock absorber for the blade, when contacting hard material like a knot or other material.

So I pulled out a small battery and tried it out. Here's the quick and lazy set up. The control is a simple three position switch, forward, stop, and reverse. There is a knob on the drum side of the winch to disengage the drum from the gear reducer so you can free wheel. This will come in handy if the feed speed is not to my liking on a small log or to fast for a large tough birch. Disengaging the winch will allow me to push the carriage by hand at a suitable speed.

This is where video would really be nice. The past three elected governments all promised affordable high speed internet for everyone. I'm still waiting, did anybody here that, ha, ha. Here I run the carriage to the back using the winch. The spring absorbed the shock easily when hitting the stop. 

Here I run the carriage to the other end, full travel stop to stop 9'.

I timed the full run and determined the feed rate at 10 fpm, At 23 hp a Norwood mill averages 25 fpm on 12-14" logs, faster for softwoods, slower for tough woods like oak, or hickory etc. The speed I determined was with a bare drum. I will add three cable raps to the drum, to bring the speed up close to 15 fpm. Since the toughest wood I have is birch and not to much of it is over 18", this should be relatively easy on the 15 hp motor.

So I used just a small lawn tractor battery, I run it back and forth at least 5 times without any noticeable loss of power. I put my weight against the carriage and I couldn't stop it, it pushed me. I doubt the charging system on the engine will keep up with usage, so the plan right now is for two large marine batteries.

So I'll spend the next couple of days fine tuning this feed and cleaning up and finishing up small stuff, to prepare for the head build.

Saturday, July 21, 2018

Carriage Ready For Power

Standing in the shop this morning, looking at the hoist on the mill, I realized I had not added a triangulated strengthening strap to the main boom. Probably not needed for it's intended purpose, but for the amount of extra weight added, it does stiffen the boom and takes some of the bounce out of it. It was a quick job to add the 1 1/2" X 1/8" strap.

So back to the carriage, I first prepared the sockets and 2 dogs for the back of the bunks. I cut the sockets from 2 1/2" tubing 3" long. I then drilled 3/8" holes and welded 3/8 nuts to line up with the holes, these accepted 1 1/2" X 3/8" bolts to lock the dogs in place.

Here I have 2 dogs installed in the socket. I will be making 2 more of theses 6" dogs and 4 more 12" dogs for handling larger logs. For now these 2 will do.

Here I have the sockets welded to the bunks and the bunks welded to the carriage, but the main focus is the two eye bolts near the bottom of the picture. I cut two lengths of 1 1/2" X 3/16" angle iron, and center drilled them to accept the 1/2" eye bolts. I welded the angle 2.5' from both ends of the carriage, at the bottom edge of the carriage. The cable feed for the carriage will be attached to these 2 eye bolts.

So I pulled back and got this picture. The carriage is pretty well complete. It still needs front dogs, but these need to be depth and height adjustable for different diameter logs. I'll visit that later. The bunk spacing will allow a log as short as 2' to be sawed, without any special jigs.

So I'm ready to start on the carriage feed.

Friday, July 20, 2018

The Carriage It Rolls

So we got started on the carriage this morning. I first cut and mitered the frame members and 4 bunks. The carriage frame is 2" X 1/4" angle, The 4 bunks are 2" X 3/16" angle.

 I then welded up the frame, taking care to keep the carriage square. I put the bunks aside for more work later.

Next I pulled out a 1 ton trolley I had purchased on sale for this purpose, many years ago. I cut the frames to separate the four wheels, and leave enough mounting plate to solidly weld to the carriage frame.

Here the wheels, all separated. The bent tabs will be used to hit stops at the ends of the tracks.

 After carefully locating and clamping each wheel on the carriage, they were welded in place.

Here is the carriage siting in its track.

Here rolled to the opposite end. A light push did it, without the stops welded in yet, I had to stop it from rolling off the end.

Here I loosely placed the 4 bunks on top of the carriage. I still need to add sockets to accept the rear fence dogs, before I can weld them in place. Maybe tomorrow.