Crown or step

[Treehuggers]

Hi. Im new here and am starting to build my mill. I have 24" diameter 1 1/4 thick flame cut blanks to build my wheels from. I was going to make them with a shoulder on the back for the blade to run against but now im thinking of crowning them instead. Im open to thoughts as to the difference. I have no mill experience but a lifetime with a chainsaw. The mill im building is going to be 70" wide and 50" tall. I was hoping to run a 1 1/2" blade x whatever thickness suggested. Still looking for a 35 horse Kohler on the side of the road somewhere. 

[trimguy]

Welcome to the forum. When I built my mill I used rubber tires, so I cant help with your question. There is a lot of knowledge here ( I don't claim to have any of it  :D ) so you came to the right place.

[Magicman]

If your blade is properly tracking there is no need to consider a shoulder/step on the blade wheel.  If your blade is not properly tracking, then you have a tracking issue that you need to address.

[YellowHammer]

There is no need for anything but a properly crowned wheel.  

You can put a shoulder on the roller guides, but the only time the band rides against the shoulder is under heavy pressure.  

[Magicman]

My response was sorta "tongue in cheek" but to be more direct; continual rubbing would cause friction and the blade to heat up.  Your blade will track on a properly crowned wheel.

Don't overlook nor discount the R&D that has already been done by the sawmill manufacturers.

[btulloh]

Don't overlook nor discount the R&D that has already been done by the sawmill manufacturers.

X2 on that.  Also check out the home-builds here on the Forum.  

[Treehuggers]

Thanks for the info. I havent started making cuttings yet but in the next week it should start to become something. Ill share when im able to. Thanks again. 

[muggs]

You must have access to a big lathe to turn those wheels on.

[Treehuggers]

Yah. Im a Machinist by trade and have a key for the shop. That helps with a project like this. Its not a fancy place. Not even a dro on the Bridgeport lol  the lathe ill use is a Bertram. Its an old jobbing shop with a line shaft and wooden floors. I started there when i was 18. Im 40 now... 

[Hilltop366]

Welcome Treehuggers. Sounds like a interesting shop and project.

In regards to the width and height I'm thinking you will want to be be able to get close to the same blade height from the bed as the maximum log width you can cut otherwise your first cut is going to be quite low on a full width log.

[Treehuggers]

I understand the height issue. It was a large internal struggle. The deciding factor was the two lengths of linear rail i have are 50" long. I want to use them for my up and down guides. Im in southern ontario. Biggest tree ive cut in my life is 54". No redwoods in my future. Lol The width is the material that im usind is recycled and just happens to be 5" channel 6" long. To make it any narrower would only make scrap.