# multi-options mini sawmill plans



## Walney Col (3 Feb 2015)

Free multi-options mini sawmill plans I'm just finishing off.

Featuring 3 versions of mini sawmills each of which uses the same basic 25mm x 25mm steel hollow box section frame and can mill logs in excess of 12" diameter. In the plans the frame is mostly bolted together for the simple reason that I intend to build the chainsaw version first then dismantle it and swap out the chainsaw carriage in favour of one of the bandsaw versions later on. If you already know which version you prefer and make a permanent heavier duty track than my flimsy ladder then there's probably a reasonable rigidity advantage to be gained from welding it together from the start. The figure in the image is scaled to 5'2" to give you a reasonable idea of it's diminutive size.





Version 1 is a chainsaw mill suitable for use with 16" electric or petrol saws.




Versions 2 and 3 are 1HP electric bandsaw mills utilising a DC treadmill motor/controller and wheelbarrow and mini moto rear wheels respectively.








Note that these plans are for a carriage that will fit_ my ladder_... no doubt your ladder is a different width in which case the length of the cross members would need adjusting.
The plans may change slightly when I start building it but there's as good a starting point as any. 

Video slideshow here:- 
[youtube]6nvywuhp9kA[/youtube]

For more details info you can download the free sketchup plans from here:- http://www.seafax.co.uk/index.php?id=multi-options-mini-sawmills

Comments/un-noticed errors welcome.

Col.


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## dickm (3 Feb 2015)

Your neighbors ain't going to think THAT is garden furniture!


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## Myfordman (3 Feb 2015)

Version 2 of the bandmill looks rather difficult to change the blade and apart from that, the significance of the two designs has eluded me so far.


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## Walney Col (3 Feb 2015)

Myfordman":ism11tre said:


> Version 2 of the bandmill looks rather difficult to change the blade and apart from that, the significance of the two designs has eluded me so far.


Wheelbarrow wheels typically have a shaft around 20mm diameter which is better able to be supported just at one end than the 10mm spindles that go through the mini moto wheels. Changing blades on the mini moto wheels version is just as easy as on the other thanks to a slot through the carriage left specifically for that. The reason the carriage has been moved inboard is that being almost 2" fatter the mini moto wheeled version had so much weight overhanging the front of the frame I thought it prudent to mount the carriage on the back rails rather than the front ones.

This picture shows how you'd access the blade changing on the version where it's not obvious.




Col.


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## Myfordman (3 Feb 2015)

OK Col,

Thanks


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## dzj (4 Feb 2015)

Band-saws of this type usually have wider and thicker blades with few tpi. I'm not sure they will fare well running around wheels of 25cm diameter.


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## Walney Col (4 Feb 2015)

I have slight reservations about the 10" wheels too hence the 12" version. This is a very lightweight mill compared to the average youtuber's DIY mill however, and the blade I've chosen as a starting point is also suitably lightweight at 13mm x 3tpi, so I think it's in with a reasonable chance of success.


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## dickm (4 Feb 2015)

Just wondering about the geometry of the ladder plus wheels, Col. Is there a danger that the wheels will catch on the underside of any irregular logs? Maybe think of some sort of V-block arrangement to raise the log a bit?


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## Jimmyarm (4 Feb 2015)

What stops the weight of the cut piece pressing down on the blade of either design as you progress along ?

Isn't that the reason most saw mill blades are vertical rather than horizontal ?

All that will happen is that the blade binds up as you progress, potentialy snapping it and injuring the operator.


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## Walney Col (4 Feb 2015)

A maximum diameter log will catch on the side of the carriage before the wheels but an irregularly shaped log COULD snag on the wheels first, but it'd be a simple matter to rotate the log so that it doesn't and/or trim any protruding limbs off with the chainsaw beforehand.


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## Walney Col (4 Feb 2015)

Jimmyarm":3qq6lret said:


> What stops the weight of the cut piece pressing down on the blade of either design as you progress along ?
> 
> Isn't that the reason most saw mill blades are vertical rather than horizontal ?
> 
> All that will happen is that the blade binds up as you progress, potentialy snapping it and injuring the operator.


I've looked at literally dozens of home made bandsaws while I was drawing the plans up and and not one of them was a vertical, and it seems that neither are any of the professional offerings at least in the sub $25,ooo price bracket. In any case a couple of small wedges knocked into the kerf as you progress is a normal enough thing to do to hold the cut open especially on chainsaw mills and the boards I cut will be a fraction of the weight of anything off any larger mill so I don't see it being much of a problem.

Check out Linda's Sawmill Cinema on youtube sometime.... their type of saw seems to be typical of what the many small sawmills are using nowadays.

https://www.youtube.com/watch?v=6Uog7gjWVbI

Col.


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## Walney Col (4 Feb 2015)

This is the home made sawmill that inspired my own efforts.




[youtube]HRNGelIVPco[/youtube]
It's built entirely from a mini-motor engine and wheels some 25mm hollowbox section and a ladder, and if mine works half as well I'll be proper suited. He seems to us it to cut veneer but there's also another video of the same mill being transported into the canadian wilderness on a snowmobile to cut timber on the spot for building some sort of weather station. 
Col.


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## blackrodd (4 Feb 2015)

There are, as you say, several horizontal bladed bandsaws out there, Woodmizer is probably the most recognised and there are some of these, on Flea bay from time to time.
I am surprised that judging by the dialogue, so many people have not seen one! 
There's a similar model at our local home grown wood yard, and you should see the amount he turns out.
I wish you the best with the build and hope you enjoy the odd bit of problem solving! Regards Rodders


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## Walney Col (4 Feb 2015)

Thanks Rodders. It's 90% about having a new toy to play with and only 10% about wanting to source my own timber. As you say portable bandsaw mills are as common as muck nowadays but lacking both the money and the space for a real one I'm more than happy trying to build my own domestic version.

Col.


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## blackrodd (4 Feb 2015)

Walney Col":22e3dpsp said:


> Thanks Rodders. It's 90% about having a new toy to play with and only 10% about wanting to source my own timber. As you say portable bandsaw mills are as common as muck nowadays but lacking both the money and the space for a real one I'm more than happy trying to build my own domestic version.
> 
> Col.




And seeing that timber in stick too, very exciting!


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## dzj (5 Feb 2015)

Isn't 15000 sf/m a bit fast? 
(Most are around 3000-5000)


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## Walney Col (5 Feb 2015)

dzj":2kzs5np8 said:


> Isn't 15000 sf/m a bit fast?
> (Most are around 3000-5000)


Yes. That's a reminder to me what the blade I bought is rated at. It's this one:- 
http://www.ebay.co.uk/itm/121280934315?_trksid=p2059210.m2749.l2649&ssPageName=STRK:MEBIDX:IT
I'll be aiming for a lot more modest 2000 sf/m with only a 1hp motor.

Col.


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## heimlaga (5 Feb 2015)

Horisontal band sawmills have became pretty common ans the bigger ones are actually pretty good. 
However I think you will have to upscale your entire design with a factor 3 to make it usable. After all you need a certain size of log to produce boards of usable width. An ordinary ladder does bend way too much under the weight of a log and your wheels are too small to allow you to use a wide enough blade to get a reasonably straight cut in a knotty log.

Woodmizer have a reputation around here for having too small wheels and consequently too thin and narrow blades to do a good job. I think their wheels are something like 50 cm in diametre which is twice your wheel diametre. Their frames also tend to be a bit too lightweight to really last. 

If I was building a bandsaw mill myself I would want the wheels to be at least 70 cm preferably 80 cm in diametre. I would use full size railway rails as tracks for the sawmill instead of your aluminium ladder. The cross members could be made from 100mm hot rolled U-channel for instance or maybe 6x6 inch timbers. Some old 12" diametre cast iron narrow gauge railway wheels of the kind that were used in mines and sawmills and industries of all kind would probably be very good for carrying the sawmill carriage. You also need proper blade guides that support the blade properly from three sides and some upright stops to prewent it from rolling or sliding sideways because of the cutting force.

A very good idea...but probably too small to do it's intended job!


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## Walney Col (5 Feb 2015)

heimlaga":23vjh4ji said:


> A very good idea...but probably too small to do it's intended job!


I think it'll do it's job just fine, but that you're perhaps misunderstanding what it's job actually is. Making a bandsaw with 70cm diameter wheels to cut a 30cm dia log is just plain daft and defeats the whole object.

Col.


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## DennisCA (5 Feb 2015)

Interesting topic in a way. I plan to use my regular bandsaw with 60cm wheels to mill logs, when I am lucky enough to acquire some. I should have the wheel size and motor power to cut to the saws maximum depth (13" or 33cm, 40cm or 16" if i remove the blade guard or redesign it so it doesn't steal 3").

I'd have to feed the log on the table however so I'd probably have to plane it flat on one or two sides or remove the table and build some kind of rolling feeding mechanism. If I remove the table though I should get like 50cm (20") of resaw capacity.


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## heimlaga (6 Feb 2015)

For sawing logs lets say 10 cm in diametre your small wheels would probably do well enough..... so yes...I was probably missunderstanding.

I know that I have a slight tendency to overbuild things but I am sick and tired of the amount of blade drift that occurs on a woodmizer cutting 30-40 cm diametre spruce logs and I would like my boards to vary less than that. It is pretty frustrating to a frame together when the band sawn 2x4s vary from 96 to 104 mm in width along their lenght. A straighter cut would require a wider and thicker blade which in turn requires bigger wheels regardless of the demand for throat size. Not quite as daft as it seems.
The stiffer the blade the greater the wheel diametre has to be. That is a rule that applies to all band sawmills and resaws. If you look at a Stenner rack table saw mill or a Stenner resaw with it's wide blade you will find that it has some pretty big wheels.

Just my oppinion....and though i have done a lot of offbearing at various sawmills and happen to know many both hobbyist and professional sawyers I am not a sawyer myself.


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## Walney Col (6 Feb 2015)

Drift occurs regularly on badly aligned band saws and I don't think I've ever once heard of bigger wheels or a wider/stiffer blade being proposed as the solution. Whatever scale it's on from 4" dia handyband saws to 48" monsters, wheels/blade alignment and blade tension are 99.9% of everything you'll ever need to fiddle with to get straight cuts.


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## blackrodd (6 Feb 2015)

As you say, there shouldn't be any problems with the blade as long as you keep the blade and wheel clean.
Perhaps copy what the others have done including the two guides.
I'm quite looking fore ward to the first stack of timber you have cut!
The only concern I would have is with the wheel barrow tyres, regarding really low speed rating of the tyre recommendation.
As it's a pedestrian vehicle, and is, therefore not rated to attain the revolutions that you will be needing  

Regards Rodders


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## Walney Col (6 Feb 2015)

blackrodd":1tb1a1ne said:


> As it's a pedestrian vehicle, and is, therefore not rated to attain the revolutions that you will be needing
> Regards Rodders


Yes. The wheelbarrow wheels have a larger spindle size and bearing and generally appear to be a lot more robust but it was because of the low rated speed of the only tyres I've been able to find for them that I got a pair of mini moto ones as backup.

Col.


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## DennisCA (7 Feb 2015)

Sure drift occurs on badly aligned saws, but everyone still says use the biggest, widest blade you can for resawing. A smaller diameter wheel will restrict how big you can go because the big resawing blades can't do too tight a turn over a small wheel.


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## Graham Orm (7 Feb 2015)

Now this is more interesting Col. Great sketchup drawings...are they yours? I hope we'll get a WIP with the build.


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## Walney Col (7 Feb 2015)

DennisCA":2yp3wzw3 said:


> A smaller diameter wheel will restrict how big you can go


It's the available workspace that's restricting how big i can go and I'm reasonable confident that it'll cut any thing that'll fit under the frame.


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## Walney Col (7 Feb 2015)

Graham Orm":17aj3sk1 said:


> Now this is more interesting Col. Great sketchup drawings...are they yours? I hope we'll get a WIP with the build.


Thanks Graham. Yes the plans are mine, feel free to help yourself.

https://3dwarehouse.sketchup.com/user.html?id=ud45537e5-7ef2-463e-a766-a26c78756d5d

Col


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## Graham Orm (7 Feb 2015)

Not something I want to build but thanks anyway. I'll enjoy watching the process.


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## Walney Col (7 Feb 2015)

The latest revelation to dawn on me is that by altering the carriage for the chainsaw I can use it to dimension timber as I go by making vertical cut as well as horizontal ones...


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## Walney Col (11 Feb 2015)

Took delivery of a load of 25x25x3 and 30x30x2 steel hollow section today and managed to get several pieces cut before it got to dark to continue. More updates as and when things happen but with a bit of luck a house move is iminent so it might be a while before I get anything built.

Col.


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