Guide for modding a stihl bar to fit a mcculloch 250?

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sliceoflife

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Hello all,

Does anyone know of a good guide with details on the process for modding a stihl bar to fit on a mac 250? Later style mounting plates if that makes a difference.
 
Husky bars are easier to modify, I made one fit a 250 in roughly a half hour. You'll need to widen the slot a bit, grind the tail radius a bit tighter to clear the drum, and turn the oil hole into a slot that reaches up to the top of the bar. If you have a grinder with a cutoff wheel and a regular grinding wheel you can do it pretty quickly, and as I recall you can utilize standard Husky-length chains.
 
I don't have pics of a modded bar, but I do have the pics below, and yes, you channel all the way through. Manufacturing tolerances vary so check and see if a husky bar will fit over the saw's studs without modding first. Other than that, just grind the red areas until they fit your saw.
Screen Shot 2022-09-28 at 9.31.42 AM 2.pngScreen Shot 2022-09-28 at 9.31.42 AM.jpeg
 
Thank you... my saw actually has a bar (16" vintage Oregon hardnose) that I haven't installed yet. What I was less sure of is the exact design and dimensions on the .404 .63 stihl and husky 36" bars.
 
Check that the oil hole will line up at all first. If so, I'd lay the Mac bar on the Stihl and trace over with a sharp tool or a marker. Start removing material. From previous posts the stud slot is pretty much good, so no worries there.
 
36" is rather optimistic for a 250 in my opinion. 24" is more like the practical limit for those models.

Mark
It is way more than optimistic it is just not feasible unless it is just for show. I have seen folks that like to show but have no go.........Folks with 7 ft bars on two man saws that are locked solid
 
Really? Searching for discussion on it, There a few dozen posts that include a couple "Itll do it but not like it", a couple claims that it's what they run on their 250... and a bunch of super 250 owners saying the supers love 36" bars and have no problem with them... and some guys running 42s and even 48s on the supers... Are the supers that much more powerful, because of a 9% larger displacement?

I also figured since I'm only running a ripping blade it'd reduce the load on it.
 
So the bar arrived with the sprocket nose bent to about a 30 degree angle.

Brand new bar. I messaged seller. I assume probably best to deal with the hassle of a return, vs trying to bend it back and spending "new bar" money on a bar that is weaker than it should be due to metal fatigue... correct?
 
Really? Searching for discussion on it, There a few dozen posts that include a couple "Itll do it but not like it", a couple claims that it's what they run on their 250... and a bunch of super 250 owners saying the supers love 36" bars and have no problem with them... and some guys running 42s and even 48s on the supers... Are the supers that much more powerful, because of a 9% larger displacement?

I also figured since I'm only running a ripping blade it'd reduce the load on it.
It's all depends on what your cutting. Out west where soft woods are the norm, long bars are also the norm. Here in the east a 50cc saw has its hands full with a 20" bar and that's pushing it. Typically you'll see a 20" on a 60-70cc saw.
There's also the expectation of the person using the saw. Kinda like towing 10k lbs with a S10 Chevy. Yep it could do it. Not the best choice but it can do it. The same load behind a semi doesn't even know it's there.
You just have to adjust your expectations. Will it spin the chain? Sure. Will it be a fast or effective cutter? Meh. Will you wear the saw out faster? Probably. Your saw do with it what you will.
 
Well, I'll be milling with it. Hardwood, but I am fine going slow. It's not going to be huge amounts at a time. I'm fine to spend an hour cutting one big slab off every weekend or so. Honestly the bigger concern I had was thumb wear from pushing the oil trigger. I'm no expert at chainsaws, but I've done a lot of work with underpowered cutting tools of other sorts before by just minimizing the rate of work I put on them, and I figured I'd try it out and feel out how fast/slow I had to move for it to succeed.
Definitely willing to pick up a bigger saw if need be, but was planning to try this one first and see how it went. Partly why I was leaning towards a stihl bar, as the cheaper 105 cc's use that format, rather than husky.
 
So the bar arrived with the sprocket nose bent to about a 30 degree angle.

Brand new bar. I messaged seller. I assume probably best to deal with the hassle of a return, vs trying to bend it back and spending "new bar" money on a bar that is weaker than it should be due to metal fatigue... correct?
See if they'll knock some $ off, straighten the tip with a vise or some hammers and blocks and run it. Worst case you can buy a new tip for ~$20, so try to get that much knocked off the price.
 
edit: So Seller wants to send me a new bar from China... so probably long arrival time (They are low on US Stock). In the mean time I will try and bend the bar back and/or replace the sprocket nose. Given that I can use this damaged bar to practice the necessary mods.

I still really appreciate your offer Woodslasher. If there's something in the 24-30" .404 x .63. range in case this thing really has no chance pulling the 36" bar, so I've got a reliable bar for it, I'd definitely be interested. Hoping to not have to replace the rim sprocket, and currently 7 tooth .404.
 

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