My first Mill or 3

[Dai Sensei]

Ok I've just bought a Stihl660 with a 25" bar, 42" bar and 60" bar. I know the 60" is probably too big for the saw, but I got a bargain (salesman mis quoted, but I held him to it). The 60" are also like hens teeth to get hold of here in Aus, and I can still use it if I ever upgrade to the 880.

Most of the timber I'll be milling at home is small stuff I have lifted into the trailer, but as I work on road projects, I have access to a lot bigger stuff on site. That's the other reason for the different bars. I also want a small mill for the small bar, but that can expand to suit the larger bars.

Anyway, I have a heap of tubing out back and have decided to make my own. Mills aren't cheap here and after buying the saw, bars and chains, I ran out of money. I've been reading all the multitude of posts and I think I'm Ok, but don't be surprised if I post a Q or 2 when I run into trouble.

I've decided on 2 simple frames, joined with a length of tube, allowing the frames to move to suit the bar size. A single frame will suit the smaller bar, the other frame joined on for the large bars, with an auxiliary oiler. The sketch below gives you a better idea of what I am talking about.

I'll post some more pics as I progress making it, but please let me know if it looks like I've made any fatal assumptions.

Cheers

 

[BobL]

I know I'm a bit of a "pot calling the kettle black" but I think your proposed design is a touch over complicated. The sliding rail mechanism is very much like my small mill and having made one that uses sliding SHS sections I would not make one like it again.

One problem to consider is the small height differential between the "tubes that get slid into" and the "tubes that slide into those". When the exposed sliding bits ride on any rails or cut log surfaces, the 2 or 2.5 mm difference in height will be noticeable and mess the slab thicknesses up unnecessarily. I added sliding sleeves to counteract this on my small mill and while that solves the problem it adds move weight. The rails need to be dead flat all the way along.

Unless you allow for a enough clearance,the accurate welding up of a set of rails that slide smoothly and meet up as you've shown is not easy. Even if they are smooth to start with they will rack and then constantly jam and be a PITA. I got around this by adding an all-thread expander/contractor which works but all this just adds weight. The other thing is that any sliding action leads to paint being scratched off which means rust. My solution has to smother the sliding bits in grease - not really that good a solution.

None the less, you can always just call me a "pot and have a go! :greenchainsaw:

When anyone asks me how I recommend handling radically different bar lengths I suggest using a couple of different conventional length rail sets.

 

[Dai Sensei]

All good comments Bob and worth taking into account. I wish I could have one like yours, or one of those Wesford or similar rigs, maybe next year.

...proposed design is a touch over complicated...

Sounds like me. I always bite off more than I can chew It is especially true considering I will rarely do much slabbing. I just had to have one, hate to see all that timber just getting chipped on site, but after clearing there is no timber till the road is open some 2 years or so down the track.

..One problem to consider is the small height differential between ...

I will be using a ladder of sorts less than the size of the frames, and less than the exposed sliding members, so I was hoping it wouldn't be a problem. But I can always use sleeves as your suggest. The bigger rigs will only be when I have a helper, so the weight shouldn't be a problem.

...the accurate welding up of a set of rails that slide smoothly and meet up as you've shown is not easy. Even if they are smooth to start with they will rack and then constantly jam and be a PITA..

Hmm, good points, especially when it will be me welding. I wont be milling all the time, so I'll only move it on set-up.

The other thing is that any sliding action leads to paint being scratched off which means rust

If it works Ok, yes big if, I was thinking of galvanising it. That will also reduce the slop in the sliding joints (but also means making it square more critical - hmm)

...have a go! ..

If it doesn't work, I've waisted about $30 worth of steel (that actually cost me nothing) and a couple of weekends work. Oiler etc can be used on the next version.

When anyone asks me how I recommend handling radically different bar lengths I suggest using a couple of different conventional length rail sets.

I did consider it, but I have heaps of square. I even thought about 3 independent rigs, which I may go back to, depends on how the first frame turns out

Cheers

 

[Matildasmate]

Great plan mate

Look's like a great plan mate , very simlpe should work a treat , just remember the RP7 for rust mate . Cheer's MM

 

[BobL]

I will be using a ladder of sorts less than the size of the frames, and less than the exposed sliding members, so I was hoping it wouldn't be a problem.

That's what I thought with mine but I quickly worked out that you rarely if ever just plonk the mill on the log and slide it down perpendicular to the log at all times. There will be branches and twigs to get around and all manner of reason for turning the mill slightly side to side as you go down the log. This is exactly when the exposed sliders will fall into the gaps. Even using sleeve will end up jolting the mill unnecessarily as you cross the gaps - making the rails smooth all the way along their length is the only way to prevent this

If it works Ok, yes big if, I was thinking of galvanising it. That will also reduce the slop in the sliding joints (but also means making it square more critical - hmm)

Galvanizing is good but watch our for locking bolts as they quickly chew thru the galvanizing. In case you are not aware of this, weld the locking nuts onto the corner of the SHS, as welding onto the faces just ends up having crushed internal SHS faces. It also gives squarer locking.

If it doesn't work, I've waisted about $30 worth of steel (that actually cost me nothing) and a couple of weekends work. Oiler etc can be used on the next version.

Yep -that's my philosophy too - if you get enjoyment out of taking a certain road to see the view for your self - why not!

I did consider it, but I have heaps of square. I even thought about 3 independent rigs, which I may go back to, depends on how the first frame turns out

That's not a bad idea. Despite the shortcomings of my small rig I really like the fact that I have two completely independent mills which I can whip out as I need.

For my next mill I will make just like my existing small mill but instead of slider type rails I will use 36" long Unistrut type galvanized rails so that it can take my 20" and 30" bars. I already have the Unistrut and it is very heavily galv.

Cheers

 

[Dai Sensei]

... all manner of reason for turning the mill slightly side to side as you go down the log. This is exactly when the exposed sliders will fall into the gaps.

Yes I seem to remember last time I used some one elses having to slide all over the place. I will make some sleeves and ensure both frames are sized to ensure there are no gaps.

...Galvanizing is good but watch our for locking bolts as they quickly chew thru the galvanizing. In case you are not aware of this, weld the locking nuts onto the corner of the SHS

I've given up on the galvanising idea, not enough clearance I think. I will paint and live with the scratches. I'll use a bit of Easy-Glide to help with lubrucation, and the usual CRC.

I did read about the locking nuts should be in the corners, but it took me a while to work out how to do it. I ended up grinding a small fall for the nut.

I then drilled a hole bigger than the bolt through the SHS (pilot then larger)

Then put a bolt through a nut, to ensure it lined up with the hole.

Then welded it up on the two outer flat faces

Worked Ok, except twice I burnt through the SHS due to my flat area being to deep and too wide. I then had to file back the bead that formed on the inside

I managed to made most of the mill today and it seems to have worked Ok, slides like a charm. I only managed to put some undercoat on the bare bits, too late by the time I finished to take any piccies. Still have the clamping mechanisms to go, I'll have to wait until next weekend.

I must remember to get a decent leather apron, got into the shower tonight and my belly has quite a bit of weld burn, straight through the T-shirt I was wearing

Cheers

 

[Matildasmate]

Hi NeiL Hell you didnt waste any time mate , eh , exellent , great stuff . Cheer's MM

 

[BobL]

Good work DS!

RE: Belly Burn. Been there and done that. The strangest one I had once was wearing a "Bob the Boozer" where the writing was in that sort of rubberized coating. The rays got though the shirt but not the writing so I sort of had an inverse welding name stamped on my gut.

Here is another way to do those corner locking nuts. It means the nots can be welded on the flat and give the whole thing a bit of strength.

 

[Dai Sensei]

Hi NeiL Hell you didnt waste any time mate , eh , exellent , great stuff . Cheer's MM

Thanks. Unfortunately I have to head to Melbourne next weekend for a funeral, so I'll now have to wait a while before it is finished.

..."Bob the Boozer" .. stamped on my gut....

Here is another way to do those corner locking nuts. It means the nots can be welded on the flat and give the whole thing a bit of strength.

I assume that is an inverted channel welded to the corner - good idea

 

[Dai Sensei]

Aux Oiler Question

Both my 42" & 60" bars are sprocket type noses. I intend putting the bolt for the aux oiler will be as close as possible to the sprocket without impacting on the sprocket itself.

My question is, should I drill the oil hole that is perpendicular to the bolt all the way through, so it spreads oil to the sprocket and chain? (ie so it comes out both sides of the bolt)

 

[Dai Sensei]

Got to spend some more time on the mills today.

I started by finishing the bar holders. I went for a simple short piece of plate welded to the SHS, then bolted them together like many other mills around. I added a plastic wheel at each end from castors to help with moving along the log. Not sure if the it will work, the wheels extend past the SHS by 5mm (less then 1/4") on sides, but line up with the corners of the ends of the SHS. Have to wait and see.

 

[Dai Sensei]

I also did trial fit-ups to ensure it all comes together. I had to make a few minor modsand used parts of an old push bike handle bars for the push handles.

The 25" bar with single frame

The 42" bar with both frames

The 60" bar with both frames and spreader bars

Still got to set up the aux oiler and give it a coat of paint, but so far so good.

Cheers

 

[BobL]

Nice work DS, you're gonna have a lot of fun with those puppies.

One comment I have is those wheels are not going to help much when making face cuts (especially the cuts on the top of the log) since the curvature of the trunk means the clamp and bolts are going to strike the bark/trunk and the wheels won't reach to stop the mill from bogging down. I would still weld a couple of skids on the front of the inboard clamps, the outboard ones are not so critical.

I would have made the vertical handle positions adjustable so they can be adjusted once you have had a go at using the mill. It's also useful to adjust these for bigger and smaller logs.

Otherwise top job for a first mill.

Paint Colour?

Go on - something lively - you want people to see you coming, right!

Bob

 

[MotorSeven]

Looks good Neil, also i am glad i 'aint the only one who can make welds look like pigeon droppings......:hmm3grin2orange:

RD

 

[woodshop]

Well I'm certainly impressed... great job. I really like the way you made this thing so adjustable in length. I also like the way you attach the sections and adjust height with those bolts in nuts welded to the frame. When you paint it, are you going to put some sort of index on the risers so you know how many inches (well I guess cm for you) the thing is set at?

 

[Dai Sensei]

When you paint it, are you going to put some sort of index on the risers so you know how many inches (well I guess cm for you) the thing is set at?

Perhaps later, I'm still debating on my rails for the log, which will affect the index.

One comment I have is those wheels are not going to help much when making face cuts (especially the cuts on the top of the log) since the curvature of the trunk means the clamp and bolts are going to strike the bark/trunk and the wheels won't reach to stop the mill from bogging down. I would still weld a couple of skids on the front of the inboard clamps, the outboard ones are not so critical.

Good point Bob, hadn't thought of that. I still have to attach a blade guard, so will do skids at same time.

I would have made the vertical handle positions adjustable so they can be adjusted once you have had a go at using the mill. It's also useful to adjust these for bigger and smaller logs.

The old bike handles didn't give me much option but to weld in place. Perhaps I should have welded them to a plate that then bolted/clamped on. I ended up putting timbers stacked in my way to hopefully get the optimum positions, that is why the postion is different on the two frames.

Paint Colour?

Bright blue, like my workshop benches .

Looks good Neil, also i am glad i 'aint the only one who can make welds look like pigeon droppings......:hmm3grin2orange:

RD

And I did try to pick the good weld :hmm3grin2orange:

 

[Matildasmate]

Top job Neil , This is one of the best design's I have seen so far , simple effective and very adjustable , also very cost effective , should be great once you get her finished .

 

[Dai Sensei]

Ok a bit more progress last Sunday afternoon. Firstly I welded a few skids on the bar holder like BobL suggested

Then I worked on the aux oiler. I marked out the position and drilled the bar - very slow process starting at small drill size then working my way up through the sizes to 1/4 hole. Each on slow speed and plenty of lube.

I chose a 6mm hex drive bolt for my oiler. I started by drilling 3/32 hole vertically by putting plenty of nuts on the bolt and holding in a vice, that way it kept vertical and straight.

Then I assembled the bolt on the bar to mark the side hole position. I used steel and rubber washers to seal the bolt on either side of the bar.

Then drilled the 3/32 side hole - I also marked the direction of the hole on the bolt head

Then finished assembling it on the bar

 

[Dai Sensei]

Lastly the aux oiler container. I just used an old bar oil container. It had a wide mouth at the top, and a level indicator on the side, so I thought it would be perfect.

I drilled a hole in the bottom and fitted my taps at the base, with home made rubber washers from an old car tire tube. I used 2 taps, one for the on/off and another for the flow regulation as has been suggested on this forum.

It wasn't easy getting the washers and nut on the inside, but I managed with one of those long extension gripper things to start it off, then tightened it up with an extension socket.

Now I just have to work out how to attach it to the mill - next weekend?

Cheers

 

[BobL]

Good work DS:

While you are at it you might want to consider drilling the same hole on the other side of the bar for when you flip the bar.

One thing I have done on my small mill is add quick click on-off garden hose fittings to the hose that connects the aux-oil line.

On this small (20" bar) mill the oil bolt does not run through the bar but drips oil direct onto the gap between the chain and the bar. This means the mill can be use by any small chainsaw.

Currently on the BIL mill I have a shower hose screw fitting (which is much easier to get of and on than using a hose clamp) but a click-on-off with auto-fluid-shut off like the small mill would be the way to go. That way every time you disconnect there isn't a flood of bar oil everywhere.

I use the click-on-off with auto-fluid-shut off for my water cooling on BIL see here.