More Wheel Ideas

[Daninvan]

Over the holidays I had planned to add wheels and a nose guard to each of my three Alaska mills. Also to buy a pair of chaps.

Well the holidays are nearly over and I have managed to accomplish 1/3 of one task. I added wheels to one of my mills.

I noticed that all the other wheels that I saw on this site were adjustable in the vertical direction. I considered a bunch of ways to do this, then decided to try wheels that were adjustable in the horizontal direction. Mostly because I didn't have anything handy and vertical on the mill to mount the wheels to. But also I wanted to keep the wheels close to the rails as I thought it would minimize any torque.

I made little 'wings' out of ipe, cut out a long slot in each, then mounted them to the side of the mill. I bolted a couple old rollerblade wheels into the slots and I am ready to go.

So now the idea is that I can move the wheels along the slots so they ride on the edge of the log, as shown in the drawing below that I adapted from BobL.

In practice (which is going to be a couple weeks still) I figure that most of the time they will be left in place a couple inches in, say where they are now more or less ('A'), and need to be moved out to give maximum cutting width ('B') only on those few occasions I am cutting at the max width my mill can handle. I can see a bit of tweaking needed already, my slots need to extend behind the mill (up in the first photo) a couple inches more to avoid losing cut width in position B.

Cheers and Happy New Year to All! I look forward to ogling everybody's milling pictures in 2010!

Dan

 

[BobL]

Hi Dan,

I will be very interested to see how you go with your setup.

I tried putting wheels on the mill rails and the main thing I didn't like was the way the saw caused the mill to rack. The other thing was when using guide boards or log rails the wheels act on the rails meaning the rails have to be held on very firm or the vibe caused them to move. This is especially annoying for me because I use rails for nearly every cut.

To minimize racking the location and hence (re)action of the wheels to the saw should be along the same line as the bar - however there is another factor to consider - read on.

In your diagram A, the wheels will also ride up and lift the mill upwards, It's much better to have the wheels rolling along as vertical part of the log below the bar when cutting the top half of the log, and rolling above the bar when cutting the bottom.

Part of the riding problem is using rounded wheel profiles like skateboard wheels. One way around this is using sharpish sided rollers like Aussie PJT uses. These seem to ride up less than roller blade wheels.

 

[820wards]

OK Dan,

I want to know what your kid said when he or she went to ride their Razor and found that someone in the household snagged their wheels to their Razor scooter.... ;-)


jerry-

 

[Daninvan]

Bobl,

Thanks for the inputs, the racking problem is not one that I had fully considered. I can see what you are saying though.

When the bar is in the top half of the log, don't we really want the wheels below the log's 'equator' so that the wheels act to pull the bar down into the log? This seems impractical on logs of any decent size. I agree when the bar is in the bottom half of the log having the wheels above the bar will act to push the bar down into the log. I guess I could just flip them over to accomplish this, with a few moments fiddling with a wrench.

One thing I could do would be to angle the wheels so they point down a few degrees, that would tend to pull the mill down into the log in all cases and resist the tendancy to pull up.

I'm not too worried about rails, I use guide board on the first cut only, and typically the first cut is the easiest (to paraphrase Cat Stevens) because it is often narrow, and the chain is freshly sharp.

I guess I need to get out there and see how this works! Any other comments or wild speculation are completely welcome. I will update with results as they come in from the field!

Dan

PS Jerry I bought the rollerblades off a lady who was expecting a baby, so my kids' toys were not conscripted here!

 

[BobL]

Bobl,
Thanks for the inputs, the racking problem is not one that I had fully considered. I can see what you are saying though.
When the bar is in the top half of the log, don't we really want the wheels below the log's 'equator' so that the wheels act to pull the bar down into the log?

Yes that would be the ideal place - but as you say . . . . .

This seems impractical on logs of any decent size.

And, if the wheels arms are too long they could also act like levers and bend the bar

I agree when the bar is in the bottom half of the log having the wheels above the bar will act to push the bar down into the log. I guess I could just flip them over to accomplish this, with a few moments fiddling with a wrench.

Wouldn't they then be between the log and the mill rails?

One thing I could do would be to angle the wheels so they point down a few degrees, that would tend to pull the mill down into the log in all cases and resist the tendancy to pull up.

Just be a bit careful, I have seen wheels pull a bar so far into a log that they jam the mill.