Dolmar PS6400 - PS7900 ( PS-6400 - PS-7900 )

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Yesterday I decided to buck up that big (~20") pear tree trunk I originally intended to try saw milling on.
I already have too much work planned for this year so that I don't need an unnecessary one - thus the pear tree trunk is going into next winters firewood pile.

I thoroughly sharpened one of my two well worn chains (the overly aggressive one) , took my PS-7900 of the shelf , re-fueled her and de-greased the clutch drum (some oil always manages to get into it) , and mounted the said chain.
Fired her up in front of my house just to make sure everything is OK as she had been sitting on the shelf for about a month.
My uncle came along and asked whether I'd be willing to buck up a ~10-12" apple tree of his.
Sure I said , chips flying everywhere - chain was unpleasantly aggressive in that small diameter tree but sharp as hell , the PS-7900 didn't even break a sweat on that puny piece of wood.

That been done grabbed my axe , a new spare chain (I thought "just in case") and went bucking up my pear tree trunk.
First two cuts were just pure awesomeness , huge chips , each cut maybe 11-12 seconds (I got a video , but it is of low quality) , chain was self feeding rigorously and the saw held some 10k in the cut - huge smile on my face.
Third cut came to a full stop maybe 1/4 through the log , I immediately knew I hit something but forced the saw/chain through the rest of the cut.
What was it that I caught with my chain?
A freaking bullet , military 7.92x57mm FMJ , but luckily the "heavy" type with a lead core instead of the "light" one that features a steel core embedded in lead.
The chain got really dull , but it cut the bullet in half and the saw didn't bog down while cutting the bullet.
NOTE: Please read post #65 as well , it turned out to be a steel core bullet after all!

On one hand I was pissed , just a half inch over to either side and I would have missed the bullet by a hair!
But then again , I was also amazed that the chain managed to eat through the bullet , granted getting really dull , but without taking serious damage (all teeth were equally dull , none bent or broken off).
Considering my luck and the fact that I had no file with me I decided to force cut the remaining piece of log instead of mounting my spare new chain and risk hitting another bullet ruining a second chain.

Once back home I re-sharpened the chain , free hand filed , and finished my day playing with my oak trunk pile.
Huge fun , BUT I NEED A FREAKIN' LONGER BAR! :mad:

Pictures below , bullet embedded in pear tree , once been split one can see the bullets penetration path and the fact that it flipped by 180° and apparently continued traveling thru the tree backwards , and dull chain teeth after having cut a bullet in half:

BulletInPear1.JPG BulletInPear2.JPG BulletInPear3.JPG BulletInPear4.JPG BulletInPear5.JPG
ChainDamage1.JPG ChainDamage2.JPG ChainDamage3.JPG

All in all , I had an interesting day yesterday! :)
 
Thanks for the great pics and report!

Personally I would throw away that chain or use it after sharpening for the "ugly" work. Just not enough left for my likings.

7
 
Thanks for the great pics and report!

Personally I would throw away that chain or use it after sharpening for the "ugly" work. Just not enough left for my likings.

7

Thanks for the likes and thanks for reading @7sleeper ! :cheers:

THAT IS one of my three "ugly work chains" , till yesterday the better of the three.
It had bush clearing duty on my PS-6400 a couple days during this month - hit stones with it several times cutting the bushes close to the ground! ;)
I tend to take all three worn chains with me and when dull just swap them out.
The eldest one is DONE , ~1/3 of the teeth are broken off , a few are bent - it is ready for the scrap can.

I just figure I don't want to have 5 or 6 work chains "in use" , one for each saw is plenty in most cases - thus I do want to wear these two worn chains out to zero and start anew with fresh new chains! :)
I do have 5 new chains waiting in line , along with 5 rim sprockets and 2 bars - I hope this statement proves that it is not a "being cheap" thing me wanting the max out of my chains.
FYI: Using only one saw I have 1 chain for at least 2 years cutting all my firewood needs!

Funny thing is , You wouldn't believe how these worn chains cut when sharpened properly - it is freaking amazing! :crazy2:
That chain pictured in my previous post cut 40+" oak yesterday after I re-sharpened it , it went through the logs like a hot knife through butter! :rock:
I might get some pictures of the cuts and chips later.

P.S.: Those chain pictures were taken after hitting the bullet and force cutting the remaining pear tree trunk up , another 3 bucking cuts - thus it got gunked up a bit.
It cleaned itself nicely cutting oak after been re-sharpened. :)
 
I have a tin of steel core 7.62x54R from the 50s and a newer one from the 80s. Nasty stuff and scary what it will go through. It does make the ole Mosin look like a fire breathing dragon though lol. I always like your reading your posts and seeing your Dolmars.
 
I have a tin of steel core 7.62x54R from the 50s and a newer one from the 80s. Nasty stuff and scary what it will go through. It does make the ole Mosin look like a fire breathing dragon though lol. I always like your reading your posts and seeing your Dolmars.

Thank You for Your likes & for reading my posts @nnero ! :cheers:

Sorry , no Dolmar's in my last two posts nor this one - but they were involved/mentioned nonetheless. ;)

NOTE: I have been looking at this bullet leftover and it looked somewhat odd - the core seemed layered though it shouldn't if it were a pure lead core.
Turns out that the bullet is a steel core embedded in lead after all - that makes the whole thing even more awesome! :surprised3:
That notion also explains why the bullet flipped by 180°.
The "light" bullet is shorter then the "heavy" version , it also has a cutoff tail end reducing stability , whereas the "heavy" one features a more aerodynamic narrowed tail end.
Sorry , couldn't force my phone to focus on the bullet instead of my fingers. Under a specific angle one can clearly see the difference in coloring. And , yes the core is magnetic and can't be cut with a knife! I might decide cutting the remaining jacket open and peel it off , but not today. The two red lines mark the lead layer:
DSC00210.JPG

Two of the cuts and the resulting chips I made with the bullet eating chain , yesterday , after re-sharpening.
Both those cuts were perfectly self feeding:
DSC00199.JPG DSC00200.JPG DSC00201.JPG DSC00202.JPG

My "dirty work" chains , in following order:
#1) fully worn ready for the recycle bin
#2) 3 years old worn but still good chain , pleasant to use , not aggressive
#3) bullet eating chain , even worn this far still extremely aggressive and unpleasant to use in small wood:
DSC00203.JPG DSC00204.JPG DSC00209.JPG

Thanks for reading! :)
 
I thought only Slovenians were cheap enough to use a chain like that.:lol:

Watch out , there might be one or two around! :innocent:
And don't You dare insult us Croatians , when we wear out our saw chains we put them on our bicycles and drive in circles till the tie straps give up! :laugh:

Don't tempt me to try and figure out how to upload videos... :p
That third chain made two perfectly good bucking cuts (~11-12 seconds) in that 20" pear tree trunk before it bit AND chewed through the bullet!

If a chain worn like that would cut (significantly) slower then a new one , then I would consider replacing it earlier.
But these chains cut wood as good as new ones , properly sharpened maybe even a tad faster.
This claim is not valid for the chain featuring missing and bent teeth , that one truly is scrap metal now - may it rest in piece.

But then again , what do I know?!
Most of You guys would scoff at my saw usage amount!

Let it be said though , on a one saw plan:
- I have one bar for the last 9 years
- one chain lasts me 2-3 years
- I change the rim sprocket each time I put a new chain on my saw , even though I realize it is far from being worn out
- I have never had to swap out any rubber parts nor carb kits
- nobody thought me anything chainsaw related , whatever I think I know I figured out myself
- I strictly mix my own fuel @ 50:1 using unleaded EuroSuper95 and Dolmar 2-stroke oil (I might have to switch brands though as I have difficulties buying the Dolmar oil lately)
- I use chainsaws ever since my mid teenage years and I have yet to hurt (or god forbid , kill) myself with said tool

I would say EACH TO ITS OWN , do what works best for You under the given circumstances! :)

Thanks for reading @jar944 ! :cheers:
 
Watch out , there might be one or two around! :innocent:
And don't You dare insult us Croatians , when we wear out our saw chains we put them on our bicycles and drive in circles till the tie straps give up! :laugh:
:)

Ha all in good fun. I've been called a "cheap Slovenian" too many times to count, even though my grandfather was from Vele Mune
 
i pulled the ones off my shelf to check.

i wonder how much the HD filter hurts performance? when you install them you have to lean out the carb so that indicates it is restricting the airflow. Anyone tried timed cuts back to back to verify?

The felt prefilter is what kills air flow, remove it and throw it away!
 
Tell us how you really feel

Hi Nate , nice of You to drop in! :)


:)
Ha all in good fun. I've been called a "cheap Slovenian" too many times to count, even though my grandfather was from Vele Mune

You know what , I'll help You prove them evil tongues wrong!
You take all the chains You deem worn , pack them up and ship them to me.
Don't forget to sharpen them first though , I don't won't to bother with that!
If Your chains have a pitch other then 3/8" don't forget to include adequate standard spline rim sprockets.
Feel free to do all that at Your own expense.

How does that sound , am I now cheaper then You? :p
 
...I intend to fell and buck 2 pear trees this weekend (a third one already went down last Saturday).
...The one pear tree that went down , and the other two that will follow: :chainsaw:
View attachment 396796 View attachment 396797
You guys with Your fancy videos featuring chainsaws made me register at YouTube and upload a video of my own!
Be gentle , it is my first video upload:
 
Third cut came to a full stop maybe 1/4 through the log , I immediately knew I hit something but forced the saw/chain through the rest of the cut.
What was it that I caught with my chain?
A freaking bullet , military 7.92x57mm...
The chain got really dull , but it cut the bullet in half and the saw didn't bog down while cutting the bullet.
Don't tempt me to try and figure out how to upload videos... :p
That third chain made two perfectly good bucking cuts (~11-12 seconds) in that 20" pear tree trunk before it bit AND chewed through the bullet!
And a video of that day as well!
I hope You like it:
 
Dolmar PS-6400 & PS-7900 parts & articles purchase 11-2015 - part 1

I treated myself and my saws a little, ordered and received some Dolmar parts/articles.

Just to be clear neither of my two big girls need any parts replaced, this was part of a favor buy I did!

So, here goes - NEW STICKERS:

- clutch cover "Dolmar" sticker , part # 980114593 (factory original/new)
Dolmar sticker-factory.JPG Dolmar sticker-new OEM.JPG

- starter assembly "Dolmar PS-6400" sticker , part # 980115674 (factory original/new)
Dolmar PS-6400 sticker-factory.JPG Dolmar PS-6400 sticker-new OEM.JPG

- starter assembly "Dolmar PS-7900" sticker , part # 980115672 (factory original/new)
Dolmar PS-7900 sticker-factory.JPG Dolmar PS-7900 sticker-new OEM.JPG
 
Dolmar PS-6400 & PS-7900 parts & articles purchase 11-2015 - part 2

NEW "RED" Air Filter cover, part # 038118022
Dolmar PS-7900 RED AF cover 01.JPG Dolmar PS-7900 RED AF cover 02.JPG Dolmar PS-7900 RED AF cover 03.JPG
Dolmar PS-7900 RED AF cover 04.JPG Dolmar PS-7900 RED AF cover 05.JPG Dolmar PS-7900 RED AF cover 06.JPG

It features the new design with the pre-filter mesh, looks promising - big chips finding their way to the felt filter should now be a thing of the past.
I like the look of this design very much!
 
You guys with Your fancy videos featuring chainsaws made me register at YouTube and upload a video of my own!
Be gentle , it is my first video upload:

And a video of that day as well!
I hope You like it:

Obviously your pear is very rotten, because we just heard in recent days that a dolmar could never be that fast...


:lol:
NICE vids!!!

7
 
Dolmar PS-6400 & PS-7900 parts & articles purchase 11-2015 - part 4

European (small) felling/bucking spikes, INNER power head spike part # 038250021 , OUTER clutch cover spike part # 957250060
Dolmar PS-6400 Europe spikes 01.JPG Dolmar PS-6400 Europe spikes 02.JPG Dolmar PS-6400 Europe spikes 03.JPG Dolmar PS-6400 Europe spikes 05.JPG
Dolmar PS-6400 Europe spikes 06.JPG Dolmar PS-6400 Europe spikes 07.JPG Dolmar PS-6400 Europe spikes 08.JPG Dolmar PS-6400 Europe spikes 09.JPG

Mounted the outer spike yesterday, didn't have the chance to cut some wood with the PS-6400 and its new outer spike yet.

Should help improve handling though! :)
I kept my factory OEM inner spike, it looks as if the inner & outer spike line up decently.

To be continued, a few other goodies still to be listed...
 
Obviously your pear is very rotten, because we just heard in recent days that a dolmar could never be that fast...


:lol:
NICE vids!!!

7
Those Dolmar PS-7900's aren't worth $hit, they should all be sent to Croatia for proper storage till disposal!
I am willing to offer my back yard for piling up all them junk PS-79xx saws! :D

You are right, if that pear hadn't been rotten that poor excuse of a saw wouldn't have gotten through it! :rolleyes:
I usually use my Dolmar PS-7900 to cut warm butter in half, does it quite decently too - chain must be very sharp though, and the oiler barely keeps up while maxed out too. :p
 
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