Homemade Mini Mill

[BlackCoffin]

Designed my own mini mill and tested it out today. Worked pretty well but I do have some small improvements already for it. Very smooth to operate though! Using a 2x8 as a guide there is just a touch of play so the finish is rougher than I'd like. An aluminum frame to fit tight would be the future goal.

 

[BobL]

Really Nicely fab work there!

One potential problem I can see is the same as all these types of mills is the cutting direction will throw chips all over the guide board.
This means the rollers have to roll up over chips and this will contribute to the mill rocking side to side.
To prevent the chips getting on the board some sort of sweeping or ploughing device might help.
Something else that would help is to setup the mill so the saw cuts the other way i.e. with the top of the bar as this squirts most of the sawdust downwards away from the guide board.
To do this the mill has to be modified so that the mill holds onto the guide board and the guide board has to really be well fixed to the log.

You might get some ideas of how to do this from my mono-rail design
http://www.arboristsite.com/community/threads/first-go-at-making-a-mini-rail-mill.96379/
It has 3 different bar clamp mechanisms
This thread shows it being used to make middle of the log cuts for nature playground furniture
http://www.arboristsite.com/community/threads/nature-playground-milling.294273/#post-5779611

BTW , while cutting with the top of the bar reduces the amount of sawdust flung upwards it doesn't eliminate it. The chain always seems to drag some sawdust around the nose and throw it into the air.

 

[DTrap]

Looks great and seems to make nice cuts. Good work.

 

[BlackCoffin]

Thanks! The plan is to place a strip of UHMW in front of the first roller as a sweep to hopefully reduce sawdust buildup under the roller and possibly something off the side cover to help direct the sawdust a bit...but like BobL said you can never get away from them.

BobL that's some creative stuff you've got going! I may have to steal some ideas ones of these days.

 

[Ted Jenkins]

Black that device you built looks like a really stupid crazy ridiculous contraption. So ridiculous is it that you could probably sell many of them here on AS or elsewhere. Very nice job indeed. My suggestion would be to get rid of the spikes and maybe a slightly longer bar so that the saw could be run at a bit of an angle to allow for the sawdust not to hit you straight in the face. If the bar is a little bit of an angle it seems to cut much faster and have more of a noodling effect on the wood. From my experience is if you get rid of the spikes and use something on the order of two solid 3/4''X 6" X 2 1/2'' solid bars for clamping over your chain bar it would make the chain bar more rigid and not wonder as much. Other than that it looks practical simple effective and easily mobile. Thanks

 

[BobL]

To make the whole thing more rigid the powerhead can be stabilised otherwise it is too free to move and this movement above the guide board is transmitted .
Something like this which connects the bar clamp to the bar bolts makes a significant difference.
To tension the chain in the mill the bar clamp bolts are loosened (because the saw is still held to the mill by the saw bar bolts), the chain is retensioned and then the bar clamp bolts are done up

This setup is allows the bar to rotate (360º) about a pivot point at the bar clamp and was incorporated specifically to be able to start cuts in the middle of logs or slabs and makes all sorts of angled cuts.

The pivot can this be locked into place at any angle and I have made many cuts at all sorts of angles but not noticed any improvement in cutting speed using changes in angle less than about 45º.
Remember as the angle is increased this also increases the cutting width. At 45º the cut is 41% wider and it seems like these two factor cancel each other out.
It's only when the angle is great than 45º that I can notice any change in speed but this is only possible on very short logs that are not that much as long as the bar.

What a shallower angle of cut does help with is stability as there is more bar in the cut so it self stabilises and this can improve the finish.
This information was obtained from milling park furniture from logs where all sorts of weird cuts need to be performed.

The same principles about angles apply to alaskan mills

 

[BlackCoffin]

I do like the mount up onto the bar studs. I may add that for extra rigidity and safety. Plenty of great ideas!