Tapering With Alaskan

[welaf]

Hello fellow CAD comrades.

I have been lurking around this site for a while now and have learned a lot from all the posts.

I have a MKIII and have been milling small (12-18in) pine and hemlock with my 365 special and have come up with a few questions.

1. What is the best method to insure there is no taper when entering the cut after the initial slab has been removed. I have been seeing this problem for several logs now. I have been setting the depth mostly to 2 inches with a scrap I have. I place the scrap between the bar and the mill on the powerhead side then set that depth and slide the scrap over to the other side of the mill and repeat. This was to insure a level cut between the mill and the bar.

However I still seem to be getting a taper in some of my cuts.

2. does the scale on the mill actually work? I Can not figure out how or what it measures off of.

Sorry for the long winded post

I appreciate all of the great posts on this site!

As a side note, I am trying to figure out how to justify a 4rth saw to the better half She just doesnt understand why a man would need 4 saws...or more

 

[BobL]

1. What is the best method to insure there is no taper when entering the cut after the initial slab has been removed. I have been seeing this problem for several logs now. I have been setting the depth mostly to 2 inches with a scrap I have. I place the scrap between the bar and the mill on the powerhead side then set that depth and slide the scrap over to the other side of the mill and repeat. This was to insure a level cut between the mill and the bar.

The best way is to use log rails for every slab.
Like this:

Start the mill on the rails and just slide it into the log!
When you exit the log - no drama. Exit the cut and let the mill sit their idling and cooling down for 30 - 60s.

As a side note, I am trying to figure out how to justify a 4rth saw to the better half She just doesnt understand why a man would need 4 saws...or more

Tough one - my better half owns a horse - anything I spend on saws is chicken feed compared to what that thing costs to run!

 

[welaf]

Thanks for the quick response! Ill have to try that.

I dont have rails like that but ill use my 2x12.

I see your point on the horses, Im glad mine doesnt have a hobby more expensive than mine!

Ill try that tonight! I have an 8' section of hickory i have been meaning to get to.

What about the depth setting? do most of you just use a tape or some other trick?

Thanks Again!

 

[mtngun]

I do use the scale on the Alaskan. It works fine. Plus I use a guide board on every cut, as BobL suggested.

My guide board is 1 1/2" thick so I have to subtract 1 1/2" from the measurement on the scale.

For example, if I want to cut a 1" thick slab, I set the scale at 2 1/2", or 2 5/8", since I like to err on the thick side.

If I want to cut a 2" thick slab, I set the scale at 3 1/2", or 3 5/8" to be safe.

This works well as long as the guide board is flat, straight, and screwed to the log. Recently my prized guide board got wet and warped, and has been causing imperfect cuts.

I bought some unistrut to make a BobL-type guide rail but haven't got around to assembling it yet. Like almost everything BobL uses, the unistrut is heavier than I like, and that's one reason I have continued to use the warped guide board. But, I really should switch to the unistrut, at least until I can afford a good aluminum guide system.

Anyway, yes, use the scale. Your setup blocks should work fine, too, but check them against the scale before you tighten the u-bolts.

 

[welaf]

Thanks MTNGUN!

I wonder if there is somthing wrong with my scale then.

Say i take a tape and set the mill to 2" then look at the scales on the mill I cant find one edge that lines up with the 2" tick mark. Also one of the scales faces out and one faces in.

What part of the assembly is supposed to line up with the tick mark?

 

[BobL]

I bought some unistrut to make a BobL-type guide rail but haven't got around to assembling it yet. Like almost everything BobL uses, the unistrut is heavier than I like, and that's one reason I have continued to use the warped guide board. But, I really should switch to the unistrut, at least until I can afford a good aluminum guide system.

Just for the record, very little is original around here, my log guide rail design came from I think it was CaseyForrest?

 

[ShoerFast]

When I built my mill, I asked a few questions here and the answers were fantastic.

To help with wood entry and taper I made my mill a little wider and gave it a couple cross supports to ride into the wood better,,,,, but it stihl was not fool-prof.

One taper and your chasing it the rest of the cuts, 2x12's are my mill-rail and the only sure way to enter the wood.

Another $0.02 cents worth, wedges, use a lot of them, but don't over drive them, hand fit snug is fine. (I have a very fine oak board that runs 1 1/4" - 1" - 3/4" - 1" -1 1/4" want it?)

 

[hazard]

I have the granberg mill also. I only use rails for the first cut.

I bought another center brace so I have two on the wood when I start my cut. I pust down on the front of the mill when I start the cut until the bar is buried in the wood. I get very little taper if any.

I hope what I type is understandable

Chris

 

[Kicker_92]

Another $0.02 cents worth, wedges, use a lot of them, but don't over drive them, hand fit snug is fine.

I measured the kerf on a couple of sample cuts, then cut some strips of plywood on the table saw to that thickness.

As you go down the cut, just keep sliding in a spacer to keep the cut open every 4ft or so. This will keep it from pinching without lifting one end of your guide rail.

I think it was in Mallof's book on chainsaw lumbermaking, but can't remember. Work well though, especially on long cuts.

 

[mtngun]

Thanks MTNGUN!

I wonder if there is somthing wrong with my scale then.

Say i take a tape and set the mill to 2" then look at the scales on the mill I cant find one edge that lines up with the 2" tick mark. Also one of the scales faces out and one faces in.

What part of the assembly is supposed to line up with the tick mark?

Sorry for the slow response. I have a short attention span and tend to forget about a thread after I've posted once.

The top piece lines up with the tick mark. Here the tic mark is set to 6 1/4" (because 6 1/4" will just clear my end boards on the initial slabbing cut).

Now, if I measure from the bar to the bottom of the mill's guide rail, it is nearly 6 1/2", not 6 1/4". Of course, that doesn't take into account that the kerf is slightly wider than the bar, so the distance from the guide rail to the kerf is probably closer to 6 3/8". So maybe it is not exactly the same as the tic mark but is pretty darned close and has always given me good results.

As I said before, I usually set the tic marks 1/16" - 1/8" larger than I want the board so that the thickness errs on the large side.

 

[welaf]

Very good pictures. I apreciate you taking time to show me that.

I need to go take a look at mine again. If i remember correctly the tick marks on one post do not correspond with the other. Maybe i was just looking at it wrong.

Im out of town this weekend but will post back monday or tuesday and let ya know what i find out.

side note. Milled some hickory the other day. The thickness from one edge to the other was within 1/16th the length of the board.
Not too bad.

Man, this milling thing is fun!

Planning to build a milling shed next weekend. Ill post a new thread with Pictures when it begins to come together.

Thanks Again

 

[Brmorgan]

The index marks on the depth posts should both be facing the same direction, which is away from the saw engine. If yours are both facing the center of the mill, likely you have the far end crossmember on backwards. The edges with the "v" section that holds the guide posts should both be towards the engine. Measurement is made at the top of the crossmember - just line up the depth you want with the top edge of the "v" and you've got it. In Mtngun's first photo this area is right beside the 9 on the tape measure.

My mill's indexes are generally pretty accurate, I'd say +/- 1/16". Of course I make some cuts with 3/8 low-profile narrow-kerf chain, and some others with really heavy .404 chain which has a kerf probably 1/4 - 1/3 wider than that of the low-pro - so it's impossible to have a depth index that will be spot-on accurate considering such variables. If I'm cutting rough pieces that aren't going to be planed down to size for finished work, I'll generally cut 1/16" thicker than the desired size for the low-profile chain, and up to 1/8" thicker for the heavier 3/8 standard or .404 chain. For anything being planed down I usually cut at least 1/4" thicker than the intended finished size to allow for warping.

I was also going to suggest that your problem might lie in not using enough kerf wedges to hold the cut open. Maybe you are, but you didn't mention it and the symptoms would fit the bill. What can happen is that without proper kerf wedging, the weight of the top slab can push down on the chain and make it take a heavier bite out of the remainder of the log/cant. This might be negligible and go unnoticed for a couple cuts, but if you're working with a decent-sized piece and make half a dozen or more successive cuts, even a 1/32" inconsistency will add up to a significant amount. Hazard made a good point too, about the mill's secondary cross brace that the handle is mounted on. Ideally this should always be set near the center of the log you're cutting. I never thought about adding a second one for added stability but I do think I'll look into it now. Not like it would change the weight significantly.

It just occurred to me that you might be talking about a taper issue across the width of the board, since your concern is with the depth posts not lining up with each other. If that's the case, I don't really know what to suggest if you are in fact setting both depth posts to the same measurement properly. Take both posts out of the mill and set them side by side to see if the index marks line up properly. Also set the mill itself on a known flat surface to see if it is flat and square. It is possible to misalign the mill through an improper sequence of nut-tightening during assembly and saw mounting, so the mill rails might be out of parallel which could certainly cause a tapering issue.

For myself, I've found the best sequence for first mounting a saw to be: Tighten the depth posts to the desired depth, and loosen the nuts on the far-end crossmember and slide it out of the way. Insert the saw bar through the near-end post and clamp it in fairly tight but not locked right down yet. Then, slide the far-end depth post over the end and lock it down to the bar first. Once it's on the bar, set the mill on a flat surface (guide board works well) and the far-end crossmember should find its place on the rails by itself if the nuts are loose. Check visually for square and alignment, and then tighten the nuts down. Then tighten all the bar clamp nuts again. At this point the mill should be fairly well aligned. I've found that sometimes if I lock the far-end crossmember down before the bar mount, it has a tendency to put excess pressure on the bar when I clamp it down and can bend it ever so slightly. This isn't a problem with shorter bars but I have encountered it with the 33". Hope you were able to follow that description, I'll take some pics if not. I'm sure others here have their own methods that work equally well though, so take it with a grain of salt. Seems to work for me.