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rws
02-01-2015, 05:52 PM
I have an older chainsaw that the chain oiler feeds oil through a side "hole" in the bar where it tightens against the block. It is called a D176 mount on the Oregon website. However, this bar must be very hard to find, if at all, I'm still searching. The issue is the chain pitch is a bit oddball. I would post a pic if I could but I can't for some reason.

http://oregonchain.com.au/d176.html

If you look at this link, the hole shown with dashed line is the oil port in the bar. I have verified this with my old bar, the hole goes half way though the bar and has a slot that goes to the chain groove and feeds bar oil.

So my question is, I could probably buy a bar that would bolt on the saw that doesn't have this special oil port. I could mill a blind hole, but how would I get a slot from the hole to the chain groove? The chain groove is .050". You can imagine the distance a slot/hole to get from the hole to the chain groove would be.

I hope I'm explaining enough.

duckman
02-01-2015, 06:14 PM
If you check you'll find that the hole breaks into the groove in the bar.

rws
02-02-2015, 05:01 AM
Not really, I used a small wire and putting the wire into the groove and following the bottom of the groove, there is a definite "drop" that goes to the oil hole. The top of the oil hole is .570" from the top of the bar. The chain groove is .330" deep. There is a definite oil pathway cut from the bottom of the chain groove to this oil hole. But it's only .050" wide!

Abner
02-02-2015, 07:10 AM
I'm confused. What is your saw and what is your chain. I used to have .325 chain and was told to replace it with 3/8". I have never had to look at bar oil holes as they line up. I looked at both D176 and D196 and see no difference in oil porting but measurements are not included.

http://www.forestryforum.com/board/index.php

http://www.woodsindustrialsupply.com/

Willy
02-02-2015, 09:28 AM
Not really, I used a small wire and putting the wire into the groove and following the bottom of the groove, there is a definite "drop" that goes to the oil hole. The top of the oil hole is .570" from the top of the bar. The chain groove is .330" deep. There is a definite oil pathway cut from the bottom of the chain groove to this oil hole. But it's only .050" wide!

If it was me I would try using a 1/16" drill to intersect the bottom of the chain groove in the bar with the oil supply hole.
I realize that the groove is probably only about .050" wide but a Dremel with the appropriate bit should be able to open up the chain groove in that location enough so that you can use the 1/16" drill without interference.

Carm
02-02-2015, 09:36 AM
There are several ways to accomplish the objective, BUT

It is sad to bring up issues regarding litigation involving any alteration of the Mfg.'s product.

dp
02-02-2015, 09:46 AM
You can use a slitting saw or abrasive wheel (Dremel?) to machine a radiused depression in the chain groove at the blind hole you drill. Come to think of it, the hole needn't be blind if you have a TIG or MIG welder.

boslab
02-02-2015, 10:46 AM
Out of curiosity, what steel goes into chain bars, I have a few old ones and wondered if they can be recycled into something, what I don't have a clue but they are flat and ground, stihl I think
Mark

lakeside53
02-02-2015, 11:57 AM
With Pro bars 1085 is pretty common but depends on the bar and manf. Some are laminated and some solid. If you get the Stihl Pro bars (replaceable tips), those are solid and make great swords, machetes, knives etc. The edge where the chain runs is zone hardened, but the rest is tempered back to something more reasonable.

Don't overthink the oil hole. As long as it lines up with the saw oiler, and some of it makes it to the grove, it will work. The chain pitch used depends on the drive sprocket and the bar tip (if the tip is sprocketed). Lots of flexibility there.

Black Forest
02-02-2015, 12:19 PM
With Pro bars 1085 is pretty common but depends on the bar and manf. Some are laminated and some solid. If you get the Stihl Pro bars (replaceable tips), those are solid and make great swords, machetes, knives etc. The edge where the chain runs is zone hardened, but the rest is tempered back to something more reasonable.

Don't overthink the oil hole. As long as it lines up with the saw oiler, and some of it makes it to the grove, it will work. The chain pitch used depends on the drive sprocket and the bar tip (if the tip is sprocketed). Lots of flexibility there.

Also the width of the grove for the chain.

lakeside53
02-02-2015, 12:29 PM
Yes, but not the pitch... the grove width isn't directly affected by the pitch. Many overlaps.

Chain tang groove - 0.043 ( for small saws), 0.050 and 0.063 are the most common in the USA. 1/4 (went away for a long time, but now is back), 0.325, 3/8, 0.404 for pitch. Some of it is regional - for example, a 20 inch Stihl bar - Western states 0.050 is more common, Eastern 0.063, both are 3/8. Urgghh.. the Interent ordering age makes stocking chain/bars a pita.

boslab
02-02-2015, 01:33 PM
With Pro bars 1085 is pretty common but depends on the bar and manf. Some are laminated and some solid. If you get the Stihl Pro bars (replaceable tips), those are solid and make great swords, machetes, knives etc. The edge where the chain runs is zone hardened, but the rest is tempered back to something more reasonable.

Don't overthink the oil hole. As long as it lines up with the saw oiler, and some of it makes it to the grove, it will work. The chain pitch used depends on the drive sprocket and the bar tip (if the tip is sprocketed). Lots of flexibility there.
Thank you, I now have an idea, aka cleaver idea pun
Mark

rws
02-02-2015, 05:38 PM
I started looking at the old bar to see how bad it is. On the bottom side of the bar, the sides of the bar, either side of the groove, is uneven. Whether from lack of oil, uneven pressure on the bar, they aren't even. The groove width is wider in places than others.

What do I have to loose? It's already bad. Anyone ever free-hand on a mill? The bar is curved, not a straight edge to be found. So I cleaned it up, I was able to file the fin off the sides at the groove. Coated the sides/wear surface along the groove with dykem. I put an old carbide endmill that was a regrind in the collet, and used a 3/4" finished piece of wood as a way to get the bar off the table. I started milling/chewing the high edge down to the other. I tried using 123 blocks but the bar bounced worse. I'm working a couple inches at a time, trying to get a fairly good surface on both sides. Once I have it "roughed in", no pun intended, I'll smooth it out with a flap wheel, and deburr. I plan on tightening the groove by squeezing here and there and try to get it halfway close.

I'm growing weary of messing with this saw. I don't mind fixing things, but my time is limited and when I have the "spark" to cut a tree down and such, having an old contraption break down just takes the wind out of your sails.

Carm
02-02-2015, 05:52 PM
Flip the bar every, or every other, oil refill to keep wear even. Don't get slack (HaHa) about chain tension either.

You could do your machine work for the oil groove/entry hole if the bar was split (yes I am assuming it's two piece). Find the spot welds and drill out, preferably Tig it back together.

The steel is usually temepered to tough rather than hard. I've pinched a bar before and they won't snap but can take a curve that's hard to straighten.

My earlier comment still applies...no manufacturer will stand post sale fiddlin'.

Willy
02-02-2015, 06:14 PM
What I would do to level out the bar rails is to grind them instead of trying to free-hand mill them straight.
There are of course purpose built commercial bar grinders available that do an excellent fast job of evening out the bar's rails, but to get a little more life out of the bar you can do this at home.
A table saw works best as you have a nice big flat table exactly 90 to the saw blade. Replace the blade with a grinding or sanding disc and the job is almost half done.
A belt/disc grinder will do as well if the table is large enough.

Carm, don't worry about the litigation so much, the grinding dust alone will cause everyone in California to perish anyway.:)

lakeside53
02-02-2015, 09:09 PM
Yes.. I've ground and rebuilt 100's (literally) of bars... dead simple. Now days I use my tool grinder - takes a few seconds per side.

Knock off the side burrs with flat file first. Then grind by hand using a 90 degrees table/rest. If you care.. close up the rails if they are really slack (two bearing on a pivot, and stroke the bar). Don't try crushing the rail in a vice or stick a screw driver in and lever if they get too tight -the rail side will crack.

ahidley
02-02-2015, 10:23 PM
Lakeside has it correct about grinding the bar. And he describes a tool to bend tube groove back to correct dimension . The below listed site that I have no relationship with has always had any odd part that I've ever needed. They even had 1/2 inch pitch chain that is now all but unavailable. They have the tool to bend the bar backtogeter to repair a worn chain groove. It's about twenty bucks.
http://www.baileysonline.com

rws
02-03-2015, 10:21 AM
I think I'll leave the groove width alone and just get the rails even and square, then have at it! This bar has the weird oiling port that I can't flip it over.

I'm slowly talking myself out of this saw, but I'm cheap! It's heavy! I see new saws that weigh a mere 10 pounds dry.

Mike279
02-04-2015, 10:04 AM
If the groove is too wide the chain will not cut properly. Fix that first, then the edge. I have great results freehand with the belt sander, easy to follow the contours of a bar. Mike