iDRY Vacuum Kilns

Sponsors:

.404 chains for slabber

Started by Cruiser_79, June 29, 2020, 04:39:30 AM

Previous topic - Next topic

0 Members and 1 Guest are viewing this topic.

Cruiser_79

Hi there, 

I'm looking for a sprocket for a .404 chain, for building a wide slabber powered by an electric drive motor. I can only find .404 sprockets for 0.080 gauge chains. Baileys says that a 0.080 type C sprocket will fit every .404 chain, even the 0.063 gauges. Is that true or will the chain get loose or run out of the guidebar? 
What is the 'perfect' tension for a chain on a guidebar? I want to design a kind of automatic tensioner for the chain to prevent the chain to get loose when heating up in a long cut. I had some problems before when milling with an alaskan mill on my 660 with chains gettin loose in long cuts. I would like to prevent that. Don't wanna see 70'' chains slinging around  :)

terrifictimbersllc

What does the sprocket pitch have to do with the chain gauge? 
DJ Hoover, Terrific Timbers LLC,  Mystic CT Woodmizer Million Board Foot Club member. 2019 LT70 Super Wide 55 Yanmar,  LogRite fetching arch, WM BMS250 sharpener/BMT250 setter.  2001 F350 7.3L PSD 6 spd manual ZF 4x4 Crew Cab Long Bed

Tacotodd

From what I have learned, as long as the pitch is correct then the gauge won't matter.
I've learned that on your guide bar that in the middle of the long span to pick it up until the powerhead starts to come up and you should still just, maybe 1/8", have driver into the rail groove. 
I'm not quite stating this correctly but I hope it's close enough for you to understand. Anyone, feel free to correct or re-state. 
Trying harder everyday.

Cruiser_79

Quote from: terrifictimbersllc on June 29, 2020, 04:52:59 AM
What does the sprocket pitch have to do with the chain gauge?
No I can't find type C sprockets with 0.063 gauge, so I was wondering or a 0.063 gauge chain would run well in a 0.080 gauge sprocket. I want a type C sprocket so I can mount it on a jackshaft. 

terrifictimbersllc

Gauge is the thickness of the drive link or the width of the groove in a new bar.   The sprocket pitch (.404 inch) is the spacing between the drive links which fits the sprocket.  As far as I know a 404 sprocket doesnt care about the gauge.   Maybe post a link to the sprocket you are looking at for help interpreting what it is saying. 
DJ Hoover, Terrific Timbers LLC,  Mystic CT Woodmizer Million Board Foot Club member. 2019 LT70 Super Wide 55 Yanmar,  LogRite fetching arch, WM BMS250 sharpener/BMT250 setter.  2001 F350 7.3L PSD 6 spd manual ZF 4x4 Crew Cab Long Bed

Cruiser_79

Quote from: terrifictimbersllc on June 29, 2020, 06:31:08 AM
Gauge is the thickness of the drive link or the width of the groove in a new bar.   The sprocket pitch (.404 inch) is the spacing between the drive links which fits the sprocket.  As far as I know a 404 sprocket doesnt care about the gauge.   Maybe post a link to the sprocket you are looking at for help interpreting what it is saying.
I thought it might be a problem when the drive links have too much space on the sprocket that the chain or sprocket will wear out at one side. I can't check my chainsaws cause all of them are 3/8 chains with a 0.063 gauge. But apparently it isn't a problem to run a 0.063 chain on a 0.080 sprocket. This is the one I'm looking for;
https://www.baileysonline.com/oregon-404-pitch-harvester-sprocket-20mm-bore-style-b-orh-dsb404.html
I have to find out how many teeth I need, maybe the smallest for suiting the best with the GB bars. 

sawguy21

There is no problem with the chain 'floating' on the sprocket, it happens on all saws. As long as the chain is properly tensioned  the bar rails will keep it aligned.
old age and treachery will always overcome youth and enthusiasm

Hilltop366

It says "Fits all .404 chain" on the sprocket. It is the same style sprocket I used to make a DIY mill, it was never a issue.

I notice that they do not give the sprocket diameter, perhaps you can get the sprocket specs from the Oregon website. 

You should start with the desired bar and know the width to make sure the sprocket is not wider than the mount end of the bar so the drive links track properly in the grove then work back from there with sprocket size and desired chain speed to get the correct drive reduction/increase for the engine speed/horsepower. 

terrifictimbersllc

Note that you can order at 10, 11 or a 14 tooth sprocket,This is what defines the sprocket contribution to chain speed. Each revolution of a 14 tooth sprocket moves the chain 14× .404 inches. 80 gauge is a standard harvester bar, and these are harvester sprockets. I don't think they make 63 gauge Harvester sprockets. I think on my Petersen I had a 14 tooth sprocket and ran self-modified Oregon 16 harvester chain which was 63 gauge.How actually that large diameter of the sprocket is can you probably calculate from the number of teeth times 404÷3.14 I think. Pretty sure the only thing is the actual diameter affects is How wide apart the chain is spread so it would go into the bar a little further up from the end then say as smaller diameter sprocket. That gap was never an issue on my mill. The important thing is the number of teeth contribution to chain speed.
DJ Hoover, Terrific Timbers LLC,  Mystic CT Woodmizer Million Board Foot Club member. 2019 LT70 Super Wide 55 Yanmar,  LogRite fetching arch, WM BMS250 sharpener/BMT250 setter.  2001 F350 7.3L PSD 6 spd manual ZF 4x4 Crew Cab Long Bed

Cruiser_79

Thanks for all the help, very useful. I found on baileys that the diameter of a 10t sprocket is 58.3 mm, so with a optimal chain speed of 4700 ft/min I would need 7900 rpm. With a 3000 rpm motor I need a 1:2.60 ratio, if I'm not calculating wrong.... I try to have a chain speed between 4-5000 ft/min so I won't ruin the chain very soon. Does someone know the diameter of a MS880? The GB bar should fit a 880 they say. 

doc henderson

the sprocket shaft?  what diameter?.  i have one here, and can measure.
Timber king 2000, 277c track loader, PJ 32 foot gooseneck, 1976 F700 state dump truck, JD 850 tractor.  2007 Chevy 3500HD dually, home built log splitter 18 horse 28 gpm with 5 inch cylinder and 32 inch split range with conveyor powered by a 12 volt tarp motor

Hilltop366

Not sure how much power you are going to have or need but someone may know the requirements or a bit of research should find what is required, there probably is a formula for power required per tooth in the wood at one time.

What I'm getting at is your target chain speed may exceed your available power depending on the number of teeth in the cut so you may have to use a chain with less teeth or run a slower chain speed.

Cruiser_79

I was thinking of a 7,5 kw motor, but I have a 100kva generator so a 11kw motor is possible as well. Only the weight of a 11 kw motor is much more than a 7,5.  It would be best if I can take a full chain because it's easier to purchase than a skip chain.  
Quote from: doc henderson on June 29, 2020, 04:42:11 PM
the sprocket shaft?  what diameter?.  i have one here, and can measure.
I would like to know the outer diameter of the sprocket wheel, than I can check or the sprocket of a 880 isn't much smaller  than the 10 tooth Oregon harvester sprocket. Hope that the diameter isn't too big for the GB titanium guide bar.


terrifictimbersllc

The sprocket of an 880 is much smaller than a harvester sprocket.  But that is irrelevant to your use.  You are going to drive a harvester sprocket at the appropriate RPM to get the chain speed you want.  Yes the GB bar may fit an 880 but you are not using an 880 with this bar.  You are using a larger diameter sprocket running at a much lower RPM than an 880 runs. 
DJ Hoover, Terrific Timbers LLC,  Mystic CT Woodmizer Million Board Foot Club member. 2019 LT70 Super Wide 55 Yanmar,  LogRite fetching arch, WM BMS250 sharpener/BMT250 setter.  2001 F350 7.3L PSD 6 spd manual ZF 4x4 Crew Cab Long Bed

Cruiser_79

Quote from: terrifictimbersllc on June 30, 2020, 04:04:11 AM
The sprocket of an 880 is much smaller than a harvester sprocket.  But that is irrelevant to your use.  You are going to drive a harvester sprocket at the appropriate RPM to get the chain speed you want.  Yes the GB bar may fit an 880 but you are not using an 880 with this bar.  You are using a larger diameter sprocket running at a much lower RPM than an 880 runs.
I was afraid that the sprocket would be bigger in diameter than the bar at the sprocket side. But I checked a guide bar of my 660 and the bar is slightly wider than the 10 tooth harvester sprocket. So the chain should stay in the groove with the proper tension. 
Anyone knows where to find or determine the best tension? Than I can start thinking of a proper tensioning system for the chain... 

sawguy21

Lift the cold chain at the center of the bar, the drive links should not quite clear the rails. Don't retighten it when hot.
old age and treachery will always overcome youth and enthusiasm

Thank You Sponsors!