Thread: BobL throws the Chain Saw Mill in for a bandsaw mill!

Originally Posted by BobL

Thanks for the ideas.

The mill I'm using doesn't have any wood in the base so I can't really screw into it and I don't want to add any more height to it as I would lose cutting depth.

I've got some experience holding logs while milling from when I built building my small chainsaw rail mill

On the BSM the logs rest on 50 x 100 mm RHS so It will have to be something that can lock onto those.

I'm not familiar with your type of mill, but are you sure say a 40mm thick wooden base would affect things much ? I wouldn't think so.

The important point of the idea I was offering is a process that allows you to clamp very low, from the very beginning, yet with little fear the log will move significantly….. ie. 1 clamp up from start to finish…..Its the sharp beveled down dogs that make all the difference. Basically putting the saws cutting forces to work in your favour. forces push the log even tighter.

Its a very good concept. The same process works well in other things as well. Like pinch dogs in glue ups…..and ……fishscaler clamping when hand planing……and a good cant hook as well I think. Drive a chisel hard directly into timber and watch which way it wants to move. uno what I mean.

With the sharp beveled down dogs as well I've noticed I can just drop a newly cut face straight onto the wooden base and resaw it even without clamping it sometimes, because the resaw cut is low and pushes the wood hard in especially if the dogs are very sharp.

will make a 1/4 saw process as well very quick if you don't need to clamp up every time….

try the bevel dogs idea first, and then tell me what you think. (assuming you haven't tried it already. Have you ? )

just an opinion. not an expert at forces on beveled tools or anything else I've mentioned that I've forgotten to mention. 2 cents worth.

Originally Posted by dai sensei

what about some pipe clamps or similar at each end lying on their sides with timber wedges (ie trying to lift log). . . . . .

Thanks Neil.

Attaching to the ends of the logs is not always possible because often the ends are not straight and not directly above the cross supports on the mill base.

There are already some SHS sockets on the cross rails (see A above) that I can stick vertical holders into on one side, but the log can still rock side to side against these (even with wedges underneath) so I' need something on the other side.

The logs sit on 100 x 50 RHS cross beams about 1 m apart (see above), so I'm looking at something like this below (the light blue bits).
Holding the log as high up as possible requires less holding force but everything needs to be strong so I will over engineer as usual




I'll need about 3 of them to lock down a smooth round log - smooth round logs seem to rock very easily.
They will also be useful to hold a pack of wide boards vertically so they can be cut at the same time into smaller pieces

Talk about feeling like a DILL!

The mill already has one of these log lockers things on it. It was laying under all the leaves and bark in the concrete - I just didn't even think of using it!

This photo was taken during the demo when we bought the saw. You can even see the 50 x 50 wood post on the other side of the log providing the counter force

Thats what I meant….

Just remember seeing a lot of logs there in one of your pictures to mill. I think it could be fun for the first few logs, but after that, I'd be thinking about how to get it over and done with….....less clamping or no clamping at all needed with sharp bevel down dogs will make a huge difference. And there terribly easy to setup.

You can set those dogs low from the beginning.

Sorry, to draw all over you picture. I just didn't have a picture of my own. Seemed quicker to draw over yours.

Have a good weekend. I won't push the point anymore. Goodluck with it all.

Originally Posted by BobL

The mill already has one of these log lockers things on it. It was laying under all the leaves and bark in the concrete - I just didn't even think of using it!

Bob, mines got one too. They are good at clamping from say 1/3rd of the log and up, but below that the point slips off the bark. I noticed you can chainsaw a flat on the log to take the point better low down , but never as strongly as a bevel down dog setup like I've described. They flex about a bit too much for my liking.

But I think they are good for standing a board on its edge to recut.

Originally Posted by JDarvall

Bob, mines got one too. They are good at clamping from say 1/3rd of the log and up, but below that the point slips off the bark.

That's about where I'd be flipping the log over so that it's resting on a wide flat and won't rock. A small projection welded to the support rails will stop the log moving sideways.

Originally Posted by BobL

That's about where I'd be flipping the log over so that it's resting on a wide flat and won't rock.

which could be an avoidable readjustment I was talking about if just backsawing. Do you want to flip a board unnecessarily ? You can get some rocking movement still with a low clamp from the beginning, but its passable. I did about a dozern of those short logs(from that first pic I showed) about 500 diameter that way. One clamp up low at the start. No flipping or another kind of adjustment. One board after the next straight to the bottom. Possible, because it was a good low clamp up at the beginning.

And that stop you've circled in that picture would be far more effective if it was a beveled down stop like I've mentioned set low. If you flipped the board, like your saying, it would bite in with more of a self locking action. Particularly great for 1/4sawing where you need to flip the board 90 degrees over and over because you don't need to clamp against every flip.

Do you get the concept of 'beveled down stop' ? (maybe I'm not describing it well)

Do you understand the gist of what I'm saying ? Because I'm starting to feel like a broken record. I'm not trying to badger a loose or vague idea. Its marked improvement that really can't be beat. Thats why I felt inclined to share it. I certainly couldn't be buggered just arguing for the sake of being right at 2 in the morning.

cheers
Jake

Originally Posted by JDarvall

Do you get the concept of 'beveled down stop' ? (maybe I'm not describing it well)

Yep I get itI have them on the mill frame I made for breaking up small logs with a small chainsaw.







I was thing of transferring the grippers onto the band saw but I will probably make bigger versions - Yep I know totally over engineered but that's just me.

Bob,
WELCOME TO THE DARK SIDE!! Should be a handy little mill that you don't have to wear chaps to operate
Dinasaw setters and sharpeners are excellent once you get the hang of them. I use the setter at work along side the large AMV woodmizer sharpener. They do set the teeth right left straight and so on. While getting used to it take your time so as to watch the little push arm doesn't skip on a tooth. Once you get used to it it only takes about a minute to set a blade which is great. It enables me to set and sharpen about 40 blades on a Saturday morning ready for the following week.
Hook angle for our hardwoods such as jarrah and marri I use 7 degree blades, pine 10 degree and the tough stuff such as Tuart and wandoo, 4 degrees. In the tough stuff I have also experimented with a quick swipe with a raker file on the straight teeth (known as the raker tooth) to make them fractionally lower than the set teeth.
I also slow my blade speed down by dropping the revs on the motor.
good luck with it mate, I will pm you my email address should you have any queries.

Nifty

Bob

Firstly, Nifty is the expert and he is in your neck of the woods so I am sure he could be of huge help to you.

I have attached some pix that I dug out of the archives and these may be of some help, but they were not taken to demonstrate the clamping systems particularly. Don't worry about the circular saw, which I no longer have. The two mills shared the same bed and the clamps worked on the logs in the same way. There are much greater forces involved with the circular saw than the bandsaw.

My mill had several sizes of clamp and I have made up additional clamps. The original clamps and indeed those I made use heavy wall 65mm SHS (5mm wall or 6mm is even better) with one side removed. A bolt or threaded rod is passed through that with a T-bar welded on the end so the thread can be tightened by hand. This size SHS fits easily over the 50mm x 100mm bearers. I note that your mill has the same size bearers.

To that SHS a 45 deg piece of metal is fixed. The original clamps had this made of aluminium and it was bolted to the steel from the underside. Subsequent clamps I have fashioned from all steel. The aluminium is more forgiving if you carelessly contact them with the blade. In the third pic you can see where there was contact with the circular saw. That would have been a disaster with steel.

Mill log clamps reversible.jpgultra low level log clamp.jpg45 deg clamps aluminium.jpgclamping boards.jpgMill log clamp large size.jpgMill log clamp positioners.jpgmill log clamps detail.jpg

The tall uprights serve two purposes and they swing down out of the way once the log is positioned. They stop a log that is being rolled onto the mill going off the other side and they align the log with the guide bearing on the exit side of the blade. This facility minimises the rocking action that you might get when the log is still in the round.

When re sawing the boards I often use the left over heart to support the stack, because it is a real pain if they tip slightly. I also as you can see in one pic, use big "F" quick action clamps to secure the boards too.

Timber guide.jpg

You can see one of the two wheels at the front easily and the other is just visible at the back. Once the log has a flat side you don't really need the guide as you can see here, but they are most useful when it is still round.

Regards
Paul

Originally Posted by nifty

Bob,
WELCOME TO THE DARK SIDE!! Should be a handy little mill that you don't have to wear chaps to operate

I'm seeing quite a few benefits - especially being able to just stop the mill, turn off the water and taking the petrol tank and walking straight to the beer fridge after work. With the chainsaw mill the packing up was quite a bit more work.

Dinasaw setters and sharpeners are excellent once you get the hang of them. I use the setter at work along side the large AMV woodmizer sharpener. They do set the teeth right left straight and so on. While getting used to it take your time so as to watch the little push arm doesn't skip on a tooth. Once you get used to it it only takes about a minute to set a blade which is great. It enables me to set and sharpen about 40 blades on a Saturday morning ready for the following week.

That sounds pretty good to me

Hook angle for our hardwoods such as jarrah and marri I use 7 degree blades, pine 10 degree and the tough stuff such as Tuart and wandoo, 4 degrees. In the tough stuff I have also experimented with a quick swipe with a raker file on the straight teeth (known as the raker tooth) to make them fractionally lower than the set teeth.

Thanks for that info - very useful indeed

I also slow my blade speed down by dropping the revs on the motor.

That too!

good luck with it mate, I will pm you my email address should you have any queries.

Thanks, I'll definitely be in touch

[QUOTE=Bushmiller;1826971] I have attached some pix that I dug out of the archives and these may be of some help, but they were not taken to demonstrate the clamping systems particularly.[QUOTE]

Thanks Paul. This is very useful and similar to those I have in mind.

It sure looks like you were tacking some decent sized logs back then!

This is what I have come up with.

Mine is the silver green support and the other is one that is already on the mill.

The latter can easily be move perpendicular to the log along a galv pipe that is welded into that position so it cannot move to to another cross rail.
Mine can be moved along and clamped on any of the 6 , 100 x 50 RHS cross rails on the mill.


The bracket that locks onto the cross rail is cut from a section of 125 x 75 x 6 mm RHS and has two 6mm thick plates that are bolted to the bracket using 12 mm bolts.
The 600 mm long upright is 50 x 50 mm SHS with a 5/8 bolt holding it into the bracket and the screw at the top is 5/8 all thread.
Both the 5/8 bolt and all thread pass through short lengths of 1/2 water pipe welded into place in the ends of the upright.

Mine also has s subtle way of adjusting the upright to be 90º to the rail
The red arrow points to the head of a 5/16" bolt that passes right though the bracket and screws into a threaded hole on the other side. The bracket actually rides on this bolt..
By adjusting the tension on the 12mm bracket locking bolts the vertical can be rotated into the perpendicular position for the cut surface of the log to rest up squarely against. This adjustment removes any slop in the bracket that might take it away from the true vertical.


I haven't tried it out because I'm looking to make a similar log holders for the other side of the log.

I reckon the new log holder I made up is going to do the business so I decided to make 3 more.

So this makes 5 altogether with the one already on the mill being able to be used on either the blade entry or exit side of the log.
This means I canteen utilise 3 holders on one side and two on the other side of the log.
Remember these are mainly just to hold the log while the first flat and 90º cuts are being made after that the cant is place on one of the flat surfaces and is less likely to need these.
However they will be useful in other situations.

Here are all the log holders in their fully upright positions, they of course can all be rotated sideways to suit the height of the log/cant being cut.


On the blade exit side of the log I', utilising existing 50 x 50 mm SHS sockets into which I have drilled an tapped locking bolts into one corner.
The new log grippers for this side slot into these sockets and then have a chunky hinge based on a 5/8" bolt.


The locking bolt can be undone to quickly remove the holder for loading a log or the hinge can be used to quickly swing the tops of the holders over like this so they fork lift forks can fit between the support rails


These took me ages to make, especially turning and threading all those crank ends and elbows but they are done now and I'm glad I did them this way.