Mini-mill (newbie) questions

[SteveG]

I finally ordered the Alaskan mini-mill and expecting it to arrive today or tomorrow. I didn't order the ripping chain yet as I want to see how my Stihl 361 with an 18" inch bar does. I've seen reference to 2 different types of chain; 3/8 low-profile, which I'm told is smaller than the normal ripping chain, and the normal semi-chisel 3/8. Does the low-profile offer better performance? Smaller kerf? Should I just order the regular 375 (3/8) .50 gauge?

I have access to oak, elm, ash, hickory and cedar. Would milled elm be strong enough to use as structural support? I've eyed a couple of straight elms that are 20-25' feet before any branches and would like to use these (2) to span a small creek and use as beams for a bridge. Not to drive on but rather to walk across. I believe I can get 2 8x8's from them. I haven't taken inventory of the oaks but the ones I have seen don't give me the length I'll need.

I got the mini-mill because I have no way of getting the longer/heavier logs to the guy that mills for me. The max length I can safely handle is 8-10' so am anxious to see how the new mill will work for me.

I appreciate your responses and suggestions.

 

[SilverBox]

I finally ordered the Alaskan mini-mill and expecting it to arrive today or tomorrow. I didn't order the ripping chain yet as I want to see how my Stihl 361 with an 18" inch bar does. I've seen reference to 2 different types of chain; 3/8 low-profile, which I'm told is smaller than the normal ripping chain, and the normal semi-chisel 3/8. Does the low-profile offer better performance? Smaller kerf? Should I just order the regular 375 (3/8) .50 gauge?

I have access to oak, elm, ash, hickory and cedar. Would milled elm be strong enough to use as structural support? I've eyed a couple of straight elms that are 20-25' feet before any branches and would like to use these (2) to span a small creek and use as beams for a bridge. Not to drive on but rather to walk across. I believe I can get 2 8x8's from them. I haven't taken inventory of the oaks but the ones I have seen don't give me the length I'll need.

I got the mini-mill because I have no way of getting the longer/heavier logs to the guy that mills for me. The max length I can safely handle is 8-10' so am anxious to see how the new mill will work for me.

I appreciate your responses and suggestions.

Probabably be best to run regular 3/8ths for now, then if your not happy or want to try for extra performance you can deal with the headaches associated with lo pro. I run regular 3/8ths on my mini mill and alaskan, as do most of us, but I run chisel, semi-chisel in my mind is for really dirty wood.

Here is the chart I use for comparing lumber strengths:

http://www.##################/members/donp/Fblist.htm

I don't see elm on it. Here is a chart with more wood:

http://www.woodbin.com/ref/wood/strength_table.htm

Eastern elm on that chart has a very low fiberstress about 1/3rd the strength of doug fir or SYP, the most common softwoods used in construction.

I use this calculator to size beams and you have to decide what kind of load you want your bridge to bear (I punched in [1800lbs, 240" span, 16" width, 8" depth, 350 psi fiberstress, 1 mil psi modulus, 100 psi shear] and it passed so your probably fine for a footbridge) :

http://www.##################/members/donp/beamclcNDS2.htm

If your not comforable with all this, hire someone to do it for you .


Mini mill is great for milling lumber in place, its what I started with before I built my alaskan.


edit: PM if you want to know what ####################### is.. apparently its blocked here.

 

[mtngun]

Does the low-profile offer better performance? Smaller kerf? Should I just order the regular 375 (3/8) .50 gauge?

The low profile is slightly faster. It does not fit the bar's nose sprocket well, though some people ignore that and get away with it. There are problems with stretch and breakage on large saws but that should not be a problem on your 361.

I'd suggest sticking with your regular crosscut chain for a while. You may, for example, decide you need a longer bar. The mill takes up a good 3" of real estate on the bar, and then the guide board will be another 1.5". Your 18" bar will only have 12" - 14" of reach.

But, try your existing bar and chain and see what you like or don't like, and go from there.

 

[BobL]

For that length bar I'd definitely recommend the lo profile chain. I've been using it on a 441 with a 25" blade and it works extremely well.

 

[mtngun]

BobL, you say you have been using the lo-pro on your 441 yet I don't recall you posting a report on the subject here. Are you holding out on us ? Any timed cuts ? Any observations about stretch ? Which flavor of lo-pro are you using? How did you deal with the nose sprocket issue ? Inquiring dataholics want to know.

I agree that lo-pro would be ideal for a 361 mill, but considering the OP is just now getting started milling and he may well end up getting a longer bar, I was thinking he should conserve his money until he has a better feel for milling.

 

[BobL]

BobL, you say you have been using the lo-pro on your 441 yet I don't recall you posting a report on the subject here. Are you holding out on us. Any timed cuts ? Any observations about stretch ? Which flavor of lo-pro are you using? How did you deal with the nose sprocket issue ? Inquiring dataholics want to know.

Whoops - the secret is out!!!

I recently got a 25" GB 050 bar from rooshooter.

Here is a close up of the nose sprocket.

What's interesting here is, even though it looks like the sprocket teeth are jamming up in between the ties, the drivers are actually sittting neatly on the bottom of the sprocket teeth. The chain loop I show here is the Carlton consumer lopro (C-BL) but I also have regular Carlton lopro (C) chain for it

In terms of milling performance, unfortunately no firm data yet. I still need to drill the bar and set it up in the small mill etc

Last saturday was a rare cool day at this time of the year and I headed of to do a spot of milling but it was one of those days when nothing went right. I had to spend time clearing some milling space and then cutting up and moving logs around with the loader. Eventually I got BIL out and went to change the bar but realised I have brought the wrong bars with me.

Anyway gave up on milling and decided to break out the 441 with the C-BL on it. The way it tore apart some gnarly almost dry black wattle told me this stuff is going to do very well in the mill. I have used plain lo-pro extensively on my small mill with my 50 cc homelite and 20" bar where it appears to make a really significant difference. I was also pleasantly surprised at how smooth that C-BL stuff ran. I will do a side by side comparison when the whole shebang is ready and the weather cools off a bit.

I agree that lo-pro would be ideal for a 361 mill, but considering the OP is just now getting started milling and he may well end up getting a longer bar, I was thinking he should conserve his money until he has a better feel for milling.

Yeah now that I think about it I agree that is probably the wisest thing for him to do at this stage.

 

[mtngun]

I will do a side by side comparison when the whole shebang is ready and the weather cools off a bit.

OK, I don't want to highjack SteveG's thread so I'll bide my time and wait for your report. On my end, there is still too much snow to drive on the logging roads so all I can do is stay in the shop and tinker with saws.