Questions for a Linn Sawmill build

foamnone · January 09, 2019, 10:41:52 PM

Hey guys,

I've been lurking on this site for a while and have wanted to build a stationary sawmill for the past 10 years.
I Live on a small farm with 13 acres. This saw would be hobby/farm projects.

I purchased the Model 1900 kit from Linn Lumber this summer. Well, its winter! I had dreams of making a making a large 50 inch saw but came to my senses before I started the build. I scrounged up enough tube and plate to get started. (southern for dumpster diving) Will be building all the saw frame and gantry out of Tube 2.5 x 2.5 1/4

Question for anyone who has built a Linn style mill.
At what point do you need to worry about top heavy or tipping over?

Have not decided on power - leaning toward a 15 hp 3 phase 215lbs
Still need track wheels - probably use Linn's
Method for raising and lowering- probably use Linn's manual

New blades and bits are set to arrive next week. Can't wait to get started.

ladylake · January 10, 2019, 06:40:20 AM

Tube 2.5 x 2.5 1/4

That seems way to light for a saw frame. Steve

DWyatt · January 10, 2019, 06:58:38 AM

Wait for @Crusarius to chime in, he just finished up a very professional Linn Lumber build

Crusarius · January 10, 2019, 07:27:05 AM

Thanks DWyatt, I appreciate the compliment.

foamnone, welcome to the forum. As DWyatt said I just finished up a build. Well kinda finished, but is it ever really finished?

Your terminology may be different from mine. For gantry you mean mast? The part that supports the sawing head. Right?

If you are going 2 post your going to want something rectangular not square. Square will want to bow with the weight of the head hanging off the front of it. if you are going 3 or 4 post then that will be overkill for what you will be hanging off of it. I have a 110# 22 hp engine mounted on mine along with 5 gallon fuel can and the biggest deep cycle battery I could get. So I am estimating about 210-220 pounds hanging off the mast (mostly off the front). My mast is also only 2 post. I used 2x6x.188 wall. With the 2.5" for the mast what are you going to find to slide over the top of that? The Linn plans call for 2x2 for the mast and 2.5x2.5x.188 for the sleeve over the mast. If you are doing a 4 post that is a very solid setup.

I am regretting the 2 post setup. with the 2x6x.188 verticals they are great (could have used thinner wall). but the single 2x6 connecting the two uprights was a mistake. That piece twists and causes a "walking" motion when pushing the head down the track. This is on the list for upgrade in the future.

for the sawframe I have the same question. if you are using 2.5" what are you going to find to slide over it for the adjustable side?

My advice to you is keep it as light as possible. if it wasn't for my bed design using 2x2x.188 and 2x6x.188 then I would have used .120 wall for everything. I already had the thicker wall in stock.The weight savings is pretty substantial by the time you get to the end product. Now the catch 22. The Linn plans call for drilling and tapping the 2"x.188 wall. if you are using .120 wall you will need inserts.

So now you have to decide on whether to build light and add cost for inserts (which is alot easier than drilling and tapping) or build heavy and be able to drill and tap everything. My opinion, smaller lighter stiffer is the better way to go. Especially with parts you are pushing manually.

HUGE NOTE FOR ANYONE BUILDING A MILL... MAKE SURE WHATEVER YOU BUY FOR THE CARRIAGE TO ROLL ON IS COLD ROLLED. The mill scale on the hot rolled makes for a very rough rolling surface. When I build V2 the rails will be cold rolled.

I have lots more thoughts and ideas I will be happy to share. For now, I think my ramblings have confused you enough

Feel free to checkout my build thread in my sigline below. If you have any questions at all do not be afraid to ask.

Where are you located? I would be happy to let you come check out the mill. It was a fun build.

foamnone · January 10, 2019, 09:41:34 AM

Quote from: Crusarius on January 10, 2019, 07:27:05 AM

Your terminology may be different from mine. For gantry you mean mast? The part that supports the sawing head. Right?

My idea was to use 2.5 tube everywhere the plans called for 2 because it is what I have. The only thing I am looking at buying for the mast and sawing head is material for a yoke. 3x3 3/16 with shim or build it out of flat stock.

I'm concerned about hole placement with the larger stock. Any suggestions on where to focus?

If you are going 2 post your going to want something rectangular not square. Square will want to bow with the weight of the head hanging off the front of it. if you are going 3 or 4 post then that will be overkill for what you will be hanging off of it. I have a 110# 22 hp engine mounted on mine along with 5 gallon fuel can and the biggest deep cycle battery I could get. So I am estimating about 210-220 pounds hanging off the mast (mostly off the front). My mast is also only 2 post. I used 2x6x.188 wall. With the 2.5" for the mast what are you going to find to slide over the top of that? The Linn plans call for 2x2 for the mast and 2.5x2.5x.188 for the sleeve over the mast. If you are doing a 4 post that is a very solid setup.

I was planning of following the 4 post design from Linn's plans (just larger material). The slides-either 3x3 or build out of plate. My kit didn't come with any steel. I planned on making a larger saw and got a discount by not ordering as shipping any steel from Linn. I'm sure while building the saw head I will come up with a "fix" or will tweak my plans for the mast.

Please tell me any ideas you are planning on V2.

Where are you located? I would be happy to let you come check out the mill. It was a fun build.

bwstout · January 10, 2019, 10:06:07 AM

I used 3x3 x1/4 and used flat stock and built the sleeves, I know it is not what you have but the flat stock works good I lined the sleeve with 1/4 " Teflon and kept the tolerance tight. I have 1 1/4" acme screws to raise and lower the head that is powered by a wheel chair motor so for works good.

but I think that Crusarius has an outstanding build and I would look closely at what he has.

Crusarius · January 10, 2019, 10:06:44 AM

hole placement should still be the same. the only thing you will have to watch for is the 3/4" diameter adjuster holes for the guides. Make sure they are close enough to the bandwheels so there is enough adjustment to properly support the band.

V2.0 I am thinking about changing the direction of rotation. All the blades I have ordered so far are flipped for the opposite rotation. So I need to flip them to cut, then flip them back to sharpen. Not a big deal but not something I care to continue to do. This will also allow me a more balanced setup so there is less hanging off the front of the mast. Will make up and down quite a bit easier.

Still thinking about dual width as well.

I have lots of other ideas that are escaping me right now. But it seems the more I design and play with what will work for me its getting closer to a woodmizer LT-28.

muggs · January 10, 2019, 10:12:14 AM

How are you going to power that 3 phase motor? :new_year:

foamnone · January 10, 2019, 03:25:28 PM

Quote from: muggs on January 10, 2019, 10:12:14 AM
How are you going to power that 3 phase motor? :new_year:

I have a 50 hp rotary phase converter left over from a project a couple of years back. I used it to power a 25hp granulator for shredding copper wire. We moved to all 100hp shredders and obviously made my phase converter obsolete

foamnone · January 10, 2019, 04:14:17 PM

I was able to find a cutoff of 3x3 1/4 that worked out pretty good for the yoke. Had to shave the 'weld seam' on the inside of the larger tube. (more work than I planned)

I welded an old bastard file to the middle of a 3 ft piece of 1x1 tube and used the 3 ft file to smooth the seam so the smaller tube fits snugly. The yoke is only 15 inches and could attack from both sides

foamnone · January 10, 2019, 04:58:51 PM

Quote from: bwstout on January 10, 2019, 10:06:07 AM
I have 1 1/4" acme screws to raise and lower the head that is powered by a wheel chair motor so for works good.

Can you tell me more about your acme screws. Where bought, bushing/nut, did you mill the ends yourself? - will ask you about motor later.... just need to iron out the footprint

foamnone · January 10, 2019, 05:20:04 PM

Quote from: ladylake on January 10, 2019, 06:40:20 AM

Tube 2.5 x 2.5 1/4

That seems way to light for a saw frame. Steve

The plans for the 36 inch saw call for 2x2 3/16. I have somewhere between 0 - no sawmill experience. i'm using the steel I had so I can spend in other areas ... hydraulics

scrout · January 10, 2019, 05:29:55 PM

Surplus Center is your friend for ACME screws. I used 1 in by 5 TPI, if you use 4 TPI you can gauge in turns a little easier. Hand cranking will get old super fast, as a 12 inch move would be 48 turns....you will be Mr. Noodle arms in short order. I use the stock nuts.
My Linn 190A has a 18hp Briggs, 5 gallon water jug, battery, motor/gearbox for the raise/lower on the sawhead and I have never even wondered about the strength of the design. Electric sounds great, no gas, oil, starting, exhaust and noise. Perfect.
My carriage does "rack" some as well, as I use a HF winch to pull from only one side.
Since that is the direction of the saw blade it does not seem to affect anything. By far the most challenge is log handling, I need a bigger tractor! Logs are heavy SOB's.

scrout · January 10, 2019, 05:33:52 PM

Caster City has 4x2 v groove wheels for $18 each.

Crusarius · January 10, 2019, 09:32:33 PM

Quote from: scrout on January 10, 2019, 05:29:55 PM
Surplus Center is your friend for ACME screws. I used 1 in by 5 TPI, if you use 4 TPI you can gauge in turns a little easier. Hand cranking will get old super fast, as a 12 inch move would be 48 turns....you will be Mr. Noodle arms in short order. I use the stock nuts.
My Linn 190A has a 18hp Briggs, 5 gallon water jug, battery, motor/gearbox for the raise/lower on the sawhead and I have never even wondered about the strength of the design. Electric sounds great, no gas, oil, starting, exhaust and noise. Perfect.
My carriage does "rack" some as well, as I use a HF winch to pull from only one side.
Since that is the direction of the saw blade it does not seem to affect anything. By far the most challenge is log handling, I need a bigger tractor! Logs are heavy SOB's.

Can you post a pic of your mast setup? I thought I was the only one with racking issues. you are correct though, it does not effect the cut that I can see. But it sure does take alot more work to push it through when its walking.

All the weight of my carriage is focused in 1 spot I want to do power feed one day and it will be on one side. Pretty sure it will still work since I have tried just pushing from the other side and it worked better. May switch the operator side to the sawdust side.

foamnone · January 11, 2019, 10:39:53 AM

Crusarius

What is the advantage of a 2 post design? My plan is to build a stationary mill that runs on electricity. Weight is not an issue (not moving). More concerned about building something rock solid.
Phase 2 will be putting hydraulic drive and turner...yadda yadda-dreaming big. So, any racking is something I want to prevent.
Last question for now, how tall are your acme rods? - How high can you get your blade over the deck

Crusarius · January 11, 2019, 12:22:09 PM

Advantage I saw in the 2 post design was less steel, and I like to be different and unique. It did work well but in hindsight I would not do it again. For the moving parts of your mill you still want to be mindful of weight. The more it weighs the more motor you need to move it.

With just 2 vertical posts the sawframe slides on both of them. This makes it quite a bit more challenging to mount anything to the mast. Like my log scale, my raise lower switch, the throttle... The weight was negligible between the 2 designs. I went for unique and regret it. Even if it was 3 post it would be better. That way I would have a place to mount stuff. I want to have my hookaroon and cant hook connected to the carriage so I do not always have to remember where I set them and stop setting them on the bed. I already tried cutting the cant hook in half down the length of it.

If you are going stationary do not limit yourself to putting the turning and flipping on the mill. With a proper overhead setup you could do all that as well as move logs or cut beams along a chainfall.

The threaded rods are 48" long. I can raise the blade (last I remember) 38" above the bed. This may have changed in some of my revisions.

Since you are stationary I would think your going to end up in a barn or something but one of my thoughts was to build a roof right into the carriage and at the end of the day just raise the sawframe all the way up to keep the engine out of the weather.

ktm250rider · January 11, 2019, 01:07:17 PM

I started out with a 2 post design as well. I noticed mine was racking as well during trial cuts. Mine was built with 2x2x.25 steel with 2.5 slide. I picked up some 1x1to add 2 more posts and a top cross bar. That and a couple triangle plats on top stiffened the carriage significantly for minimal cost.

Crusarius · January 11, 2019, 01:20:35 PM

That was my thought as well ktm. The only trick I was going to add to that was to integrate a roof into it so I could park the sawmill at the top and the engine be out of the weather. This way I would not have to wait for it to cool and remember to cover it when done sawing.

Kwill · January 11, 2019, 01:48:31 PM

Can you define what you mean by racking. Sorry for the dumb question

Crusarius · January 11, 2019, 01:56:33 PM

when you push on one side of the carriage that side will move, then after the frame twists enough the other side will move causing a racking / walking motion.

In ideal situations you do not want the racking. It does not effect cut quality from what I have observed but it makes it quite a bit more work pushing smoothly through the log.

foamnone · January 11, 2019, 03:38:08 PM

New miter saw blade and the small mag drill bits came in early (7/16-3/4). My plan is to tack the saw head together and then drill the holes using the half inch plate as spacers for the bearings (yoke side) and use 1/2 inch plate and 1/4 plate on the other end.

Looks like I am out of 'research' time and gotta start building.

Should I start a build thread?

Crusarius · January 11, 2019, 03:41:16 PM

Nah nobody is interested in it.

ARE YOU KIDDING!?!?!?!?!? OF COURSE WE NEED A BUILD THREAD

Kwill · January 11, 2019, 04:37:17 PM

Quote from: Crusarius on January 11, 2019, 01:56:33 PM
when you push on one side of the carriage that side will move, then after the frame twists enough the other side will move causing a racking / walking motion.

In ideal situations you do not want the racking. It does not effect cut quality from what I have observed but it makes it quite a bit more work pushing smoothly through the log.

I have a 2 post but never had that issue