Mils DIY Sawmill (Will it fly or fizzle...)

milhead · August 17, 2018, 11:08:28 PM

Quote from: Magicman on August 17, 2018, 06:37:45 PM
Unless I'm missing something, it looks like you gotta take a bunch of stuff loose to put the belts on your bandwheels??

Yeah, I'm going to mount bolt-on planes to the cross support then cut a slot thru it to install the belt. I've just not gotten around to it.
I had to get the motor mocked up to tell how long the drive belt was

Magicman · August 18, 2018, 08:35:08 AM

I would consider putting an extra inside of the loop. ;) Not that they wear out or get cut by a broken blade that often but it does happen. Of course I saw "portable" and when I have a belt failure I always have a customer looking at me.

milhead · August 18, 2018, 01:15:22 PM

Quote from: Magicman on August 18, 2018, 08:35:08 AM
I would consider putting an extra inside of the loop. ;) Not that they wear out or get cut by a broken blade that often but it does happen. Of course I saw "portable" and when I have a belt failure I always have a customer looking at me.

I'm still fooling with belt sizes but at $10 it would really be worth not having to pull half the thing apart to change it, It would easily zip-tie out of the way.

Magicman · August 18, 2018, 01:42:58 PM

I would strongly recommend getting Wood-Mizer belts. They are specially manufactured to have a flat top surface and no overlap high spot which you commonly see with automotive belts. I use the "loose fitting" B 57 belts that Wood-Mizer recommends for my sawmill.

Southside · August 18, 2018, 03:35:07 PM

I second what Magicman says there. From experience I can tell you that auto parts store belts will not last nearly as long as the Woodmizer ones do.

milhead · August 20, 2018, 12:23:07 PM

I spent a few hours this weekend (OK, several hours) working out some of the minutia of belts, exhaust, mounts, drain-plugs, etc..

I have to carve a beltway through the two members to the left of the clutch, I'm planning on bolting a support to each then removing the support, cutting a 1" way for the belt then bolting the supports back on.. I'm more worried about the engine mount support than the big cross beam as it's a direction of forces thing...

I may swap the clutch and bearing on the shaft so that I don't have to remove the engine shaft bearing to change belts as well. There will be a couple wrenches involved but not having to un-mount the engine or anything that severe.

Next I need to add the fuel tank and battery tray. It's a lot of mass up high but I don't see anywhere else to put it. It's not too high, As it sits on my bench (on it's temporary legs) it's sitting about as high as I would ever put it above a bed. If it goes on a trailer It will be a bit taller, I've been hunting boat trailers on Craigslist to see what turns up.

I've ordered the Woodmizer belts, onece they show up I'll have to muster the courage to get everything aligned and see if I can spin a blade... Slowely..

And I need to clean the shop.

milhead · August 27, 2018, 02:45:52 PM

Got some more time to spend on the saw this weekend.. Engine is ready to be fired up but I need to align the wheels before I can try spinning the blade. To date the thing has never really been tensioned as I've not aligned the band-wheels.

I need to order or make some Blade guides, I think I'd like to make some and am working on rounding up some cheap stock.

I'll post a video of the first running of the head when I get it going.

Magicman · August 27, 2018, 06:15:21 PM

The blade guides need 6 way adjustment capability. You want them level with the sawmill bed, ¼" downward pressure from the bottom of the bladewheels, the flange ~1/8" behind the back of the blade, and the blade guides need to slightly point toward the direction from which the blade is traveling.

But your blade tracking will be your first concern.

milhead · August 30, 2018, 11:59:59 PM

I did not want to make alignment adjusters that were strong enough to modify alignment.

The downside of this is that I have to release tension on the blade to make the small adjustments but then clamp the pillow blocks down with the large mounting bolts.

Pretty crummy welds but I was upside down and blind.. When I take it apart next I'll clean up the mounting.

milhead · August 31, 2018, 11:47:33 AM

Finally got the head running...

Nearly forgot to put oil in the crankcase of the engine (I'd taken it out when I brought the engine to the machine shop)

Had to bleed air from the high pressure fuel line (Hope that's not a daily requirement)

The tiny set screw on the clutch is not sufficient to hold it in place.. real shaft collars on order.

Suspect I did not properly tighten bandwheel set screws... More shaft collars on order anyway.

Ran really great for a while... Then the bandwheels came out of line and the blade fell off... If I had been paying attention I would have seen it long in advance...

No Blood!

Actually the tunnel under the fuel tank has a bolted-in piece of angle that will not allow the band to leave the machine if it comes off, this works well and the band pretty much stayed in place..

Hopefully it's not damaged.. Blade Looks Fine. I'm Fine... Made my heart race though!

Sawmill Head Running - YouTube

20180830 194731 - YouTube

And *DanG, I did not have the camera running when the blade came off

Blade Came off - YouTube

Magicman · August 31, 2018, 05:20:52 PM

Wowser, that beast runs with authority so at least you will know who is the boss.

Actually when the blade is turning it is the boss. Looks good.

milhead · August 31, 2018, 06:18:45 PM

Made an amazon bearing buy and a trip to the hardware store...
Here are my blade guide beginnings..

Southside · August 31, 2018, 10:54:21 PM

Quote from: milhead on August 31, 2018, 11:47:33 AMActually the tunnel under the fuel tank has a bolted-in piece of angle that will not allow the band to leave the machine if it comes off, this works well and the band pretty much stayed in place..

Just keep in mind that this piece works if the band happens to be in the form of a loop, should she break it will be a different story. I can understand the band coming off being a shocking moment - but it is nothing compared to the BANG of a band breaking, that will make you jump even when it is contained within all of the guarding... not telling you what to do but something to really think about while you do your testing.

Nice work on the fabrication there.

milhead · September 01, 2018, 12:42:05 AM

milhead · September 09, 2018, 02:11:43 PM

Got clearance from my lovely wife to spend some more money on sawmill parts...

milhead · September 09, 2018, 02:18:38 PM

I need to shorten my bolts but I started setting up the blade guides today.

milhead · October 22, 2018, 12:43:39 PM

I got waylaid for a while with removing a wall in the house but got the head on it's own legs this weekend!

Still seeking a scrap RV I can salvage the trailer from for a bed (or at least the beginnings of one).

I still cannot weld out of position! Really ugly joints on this one.

Crusarius · October 22, 2018, 12:49:16 PM

I like the way you use the drive belt as the wheel belt. for my next build that will probably be what I decide to do.

milhead · October 22, 2018, 02:44:45 PM

Quote from: Crusarius on October 22, 2018, 12:49:16 PM
I like the way you use the drive belt as the wheel belt. for my next build that will probably be what I decide to do.

Some commercial mills use it, I like the reduction in parts... Unfortunately my blade will only run about 3500fps with the current gearing.. I'll have to add a small multiplier between the clutch and big drive pulley to get to the design goal of 5000fps. The blade manufacturer says that the blade airflow at 5000fps (about 56 MPH) is required to properly clear sawdust from the kerf. That was my design goal.
I'll add the belt-pully multiplier later, it's not a first-pass fix.

Ljohnsaw · October 22, 2018, 03:21:41 PM

Quote from: milhead on October 22, 2018, 02:44:45 PMI'll add the belt-pully multiplier later, it's not a first-pass fix.

Can't you find a slightly larger clutch/pulley? That would solve your issue right there.

milhead · October 22, 2018, 04:55:06 PM

Quote from: ljohnsaw on October 22, 2018, 03:21:41 PM
Quote from: milhead on October 22, 2018, 02:44:45 PMI'll add the belt-pully multiplier later, it's not a first-pass fix.

Can't you find a slightly larger clutch/pulley? That would solve your issue right there.

I found only a few centrifugal clutches and due to where I placed the motor I'm restricted on the clutch pulley size... You are correct that it would have gotten me up to speed on the band but I'd have to change some base design stuff. Right now the whole thing is pretty adjustable...