Finally I started the new mill (WIP)
I was going to start a new thread but thought I'd just append the story to this one.
I still haven't really decided how to clamp my height adjustment but it hasn't stopped ally boat building BIL and myself from making a start in a new chainsaw mill. I hope not too much of this post is like teaching granny to suck egs.
I started by removing the clutch and chain brake cover. The standard cover is replaced with this 12mm thick ally plate.
On top of this plate is placed the base of the mill which connects via the ally depth of cut tubes to the rails. The base is made from 6mm thick ally plate. In its final form this base will be gussted in a number of places for extra strength. I'm not happy with the amount of thread the bar bolts are hanging on by. Either I will make a thinner underplate or replace the bar bolts with longer ones.
The rails are made from a 40 x 44 x 3mm unistrut commonly used on highway signs. The middle cross piece is also a piece of the same unistrut to maintain a constant level when starting and stopping slabbing cuts. This unistrut is a "C-section, atop a, square hollow section" so it is very strong. The C-section fits a 10mm bolt and if cup head bolts are use, the square shank section near the head fits neatly in the groove and makes it really easy to tighten the bolts.
The end cross pieces are made from 70 x 40 x 3 mm thick ally angle and are what the 25mm diameter x 3 mm thick vertical ally tubes attach to. The height adjustment (not shown) will be by allthread rods and cranks as per my small CSM.
The length of the mill was determined by the length (3m) of unistrut I had available. I basically cut off a 300mm piece for the middle cross piece leaving me 2.7 m which I cut in half so the mill is 1.35m long and can hold a chainsaw bar that is ~1.25m long.
Below is as much as we've done so far all just aligned but not fixed in place. Missing is the outboard vertical height adjuster and bar clamping tubes and a couple of other bits and pieces. There is actually very little welding involved in this mill as it is mainly bolted together so it comes apart quickly for easy transport and storage.
The chainsaw bar shown looks tiny but is 750 mm long but I am eventually looking at buying a bar around 1.05 m long.
Laying it all out like this has enabled me to identify a couple of problems including one of the oil cap access being blocked when boards thinner than 50mm thick are being milled. Fortunately the key welds have not been made and I can fix this without too much problem.
Working with ally is a lot easier than I thought. I had a go at the ally welding, it was not that hard, but I guess having a $7500 welder has got to make it easy. The rest of the tools he uses are mainly woodworking power or air tools (Sliding compound mitre saw, circular saws [he cuts massive 3 m x 3m sheets with just a circular] router, drills, sanders, drill jigsaw, etc. Other tools he uses are oxy to heat before bending, angle grinder and something called a "die grinder" which looks like a large dremel - I gotta get me one of those.
The next time we have any time to work on this is next weekend - anyway I hope you can get something from this "experiment"
Cheers