Thread: The Vertical Mini Mill

Picture 1: the pieces purchased at a salvage yard (except the small piece for the bracket, that was lying around in the shed): $80 for the lot, cut to measure and with 3m of drill rod leftover. 1'' holes drilled coaxially in the bracket and in the base. The pilot holes go through the bottom of the base. Holes in the bracket widened to 26mm to allow some tolerance in the alignment.

Picture 2: the completed bracket. Holes to match the bolts keeping the saw chain in place. Reduced thickness of the joining section to allow bending without compromising the sliding function.

Picture 3 and 4: the bracket attached to the chainsaw.
Picture 5: slots cut in the base to allow insertion of the clamps. Drilled rows of holes 1mm wider than the thickness of the clamp shaft and ground them straight (sort of )

well frank it looks ok just the clamping system needs to hold the timber better using some sticks to level the timber using a chainsaw l like the wood to stay still it would be a ugly thing if it fell

Picture 1: the pieces of the base bolted together. Welding might be a more elegant solution, but makes disassembling impossible.

Picture 2: a small template made to ensure that the holes are aligned (and made the holes 1mm larger than the bolts for tolerance). Did not bother to file the burrs around the holes, thought that they would help locking the pieces, like split washers.

Picture 3: two holes in the top of the base to take dowels that keep the "cutting board" in place.

Picture 4: the "cutting board" with the dowels. In this picture it has also a thick edge that I then removed because it did not serve any useful purpose. The thickness must be sufficient for the chainsaw to bite into it a couple of mm.

Picture 5: the cutting board in place with the cutting line etched into it and reference lines marked parallel to it to measure the desired thickness of the slab.

Congratulations F&E it looks like you have done it. With a little more work and addressing the following you could have something.

- Ok so you've cut one slab in some softwood. On a horizontal mill I barely have to place any horizontal force on the CS when cutting softwood. If the chain is sharp the CS almost pulls itself through a softwood log. Now try some dry hardwood, the weight of a small chainsaw (CS) alone is not necessarily going to do it. You are then faced with having to put some force onto the CS all the way through the cut, ie at height and down low - surely this is much more awkward than a using a horizontal mill at optimum height?
- Everytime you wish to cut the next slab you have to move the log over a bit (which BTW requires energy) how do ensure the next cut is really parallel to the first? You could set up some kind of a gear driven cross slider vice arrangement but using a conventional CS mill automatically takes care of this.
- - Your chain saw mount seems like it has a lot of play both vertically and side to side. How do you get a straight cut with so much play? It might be better if your CS was placed in between the uprights rather than to one side.
- Like any fixed mill your design is length limited but perhaps moreso than most. Operating a CS above chest height (even if it is tied to a rig) is an OHS no-no. I personally wouldn't operate a CS above hip height (and never above chest height) for anything other than a very short period.
- it would be sensible to place a small guard on the nose of the saw as viewed from the front the log hides the saw and someone could unwittingly not see the nose.

In a conventional mill the weight of the CS is used to stabilise its position in space. In your design, CS stability appears to be traded for some nominal force gain. I don't think your design is any simpler than a flat mill and in my limited experience I'd much rather have stability than a nominal gain in force A horizontal mill can utilise gravity by using a cable/pulley and a some weights (but just like your mill at some stage you have to lift them up again) and avoid the above problems.

I hope you treat my questions and opinions as a challenge and please don't let me discourage your attempts to prove me wrong. Just don't injure yourself.

With the help of a template and a spirit level the rods are put in place, ensuring that the bracket slides freely. The wider the tolerance of the bracket holes the smoother the slididing but the less precise the cutting, some fine tuning might be required.

Brilliant thinking. have a greenie

Phil

Positioning the log (top, picture 1; bottom, picture 2) is easy and allows alignment of the first slab so as to make it reasonably even and usable.

A couple of wedges ensure perpendicularity and stability (picture 3). The weight itself could be sufficient for large logs, for smaller ones and the last half clamps are useful.

As somebody said, there is a lot of energy stored in an upright log. Which is good, because once it is up, the energy can be used to easily move it in the desired position.

No problem ever with oiling the bar... and remember not to cut in the direction of the brand new dust bag (picture 1).

The "cutting board" is also perfect for roughing bowl blanks without a bandsaw (picture 2).

And when you are done, this little rig can unassumely continue to make itself useful... (picture 3)

I just have to give you a greenie for the innovative use of the jig once you've finished with it for a while.

Pretty darn impressive setup, looks like I could even attempt it



cheers
Wendy

Originally Posted by BobL

Congratulations F&E it looks like you have done it. With a little more work and addressing the following you could have something.

- Ok so you've cut one slab in some softwood. On a horizontal mill I barely have to place any horizontal force on the CS when cutting softwood. If the chain is sharp the CS almost pulls itself through a softwood log. Now try some dry hardwood, the weight of a small chainsaw (CS) alone is not necessarily going to do it. You are then faced with having to put some force onto the CS all the way through the cut, ie at height and down low - surely this is much more awkward than a using a horizontal mill at optimum height?
- Everytime you wish to cut the next slab you have to move the log over a bit (which BTW requires energy) how do ensure the next cut is really parallel to the first? You could set up some kind of a gear driven cross slider vice arrangement but using a conventional CS mill automatically takes care of this.
- - Your chain saw mount seems like it has a lot of play both vertically and side to side. How do you get a straight cut with so much play? It might be better if your CS was placed in between the uprights rather than to one side.
- Like any fixed mill your design is length limited but perhaps moreso than most. Operating a CS above chest height (even if it is tied to a rig) is an OHS no-no. I personally wouldn't operate a CS above hip height (and never above chest height) for anything other than a very short period.
- it would be sensible to place a small guard on the nose of the saw as viewed from the front the log hides the saw and someone could unwittingly not see the nose.

In a conventional mill the weight of the CS is used to stabilise its position in space. In your design, CS stability appears to be traded for some nominal force gain. I don't think your design is any simpler than a flat mill and in my limited experience I'd much rather have stability than a nominal gain in force A horizontal mill can utilise gravity by using a cable/pulley and a some weights (but just like your mill at some stage you have to lift them up again) and avoid the above problems.

I hope you treat my questions and opinions as a challenge and please don't let me discourage your attempts to prove me wrong. Just don't injure yourself.

Hi Bob, thanks for your comments. I was busy posting my description, did not see your quick response. You seem to take this rather personally, far from me the idea of doing this "to prove you wrong"... I just had a need and fulfilled it with less than $100 and very little mechanical skills. I agree with you about the nature of the tradeoff between the respective strengths and weaknesses of the two designs. Hopefully my further description has already shown that the comparison is not as bad as you make it (BTW, the timber, silver birch, was dry - I have no green wood to try it on) and using a rack movement should avoid completely the already manageable tracking problems.

As far as security goes, the CS can't go anywhere it shouldn't, and it is certainly safer than using it free hand, which I believe is what you are referring to. I do not see the problem, but will certainly listen if specific risks are pointed out to me.

Cheers
Frank

Frank, I'm sorry if my post in any way upset you. I fully respect your attempt to give something new a try. I guess I still had my teachers hat on because I constantly challenge my students to "prove me wrong", which they often do and I think that is fantastic.

BTW if you want a really cheap CS mill check this out.

That's a new idea to me, I haven't seen a mill like that before, top stuff!

Originally Posted by BobL

Frank, I'm sorry if my post in any way upset you. I fully respect your attempt to give something new a try. I guess I still had my teachers hat on because I constantly challenge my students to "prove me wrong", which they often do and I think that is fantastic.

Not upset at all... I was worried my attempts at humour were seen as an attempt at oneuppery that was not intended...

BTW if you want a really cheap CS mill check this out.

Wow, that CS has certainly a lot more cutting power than my 14".... and how does that rate from the security point of view? Not to mention the well known horizontal oiling problems...

Hi Frank, interesting Mill.

I still cant see any advantage of this vertical style mill over the Alaskan horizontal style though IMHO.

Oiling of the bar on an Alaskan is not a problem with an auxiliary oiler, and like BobL said very little effort is required in pushing with the Alaskan as it pretty much self-feeds when the chain is sharp. All you need to do is control it.

Hows your knees? Wouldn't bending up and down get a little tough on the old knee joints? At least with an Alaskan you keep your back fairly straight and your knees don't get worked out at all really, especially if you put your saw down on something other than the ground like trestles when you need to work on it.

Is there much twisting flex in those upright rods?

I also might have missed it, but how are the uprights connected to the bottom section?

Not having a go, just got to ask questions because Ive never seen one like this.

When you get the rack and the worm gear, are you intending to make it a wind up and down type affair? Like adjusting the height of a drill press table?