Hi, while putting together my first 29-360 motor I have a question,
after inserting the grains into the liner agains the foreward seal
assembly that is fitted into the foreward end of the liner, there is a
gap at the aft end of the liner about 1/4 inch wide of exposed liner
before the aft end of the liner where the aft insulator washer is, it
seems to me this space will be exposed the the high temp flame and burn
through and damage the case, is this normal?, Thanks, Le
It sounds like you might have the forward seal disc installed
backwards. You should have put the thin o-ring around the seal disc,
then put the o-ring side of the seal disc into the phenolic liner. The
seal disc should be pushed into the liner slightly so that the o-ring
portion enters the forward end of the liner, and butt up against the
larger diameter portion of the seal disc. Then put the grains into the
liner.
David Erbas-White
snipped-for-privacy@gmail.com wrote:
no, i have it correct, the o-ring end is inside the liner as is stated
in my post, if it was backwards it would not be "fitted inside the
liner" as the flanged end is the same diamiter as the liner, I assume
it is not normal to have the gap then?
It's normal to have SOME gap, but 1/4" seems a bit much (but maybe my
memory is just playing tricks). Bear in mind that during flight, the
grains 'center' themselves from each other. Even if you had no gap
whatsoever, the end grain will be burning that insulator -- but it burns
so quickly that the insulator does not have time to burn through.
Bottom line, I wouldn't worry about it...
David Erbas-White
snipped-for-privacy@gmail.com wrote:
Thanks Dave, was thinking about how fast it will burnout, the grains
were a very tight fit even after unwraping a layer of paper off of
them, I had to pretty much force them in with a dowel, no damage was
done to them, do you think they will still center out or should i
disassemble and sand them some ? Thank you a milliuon times over for
your input, Le
First, I'm not an expert, but...
I wouldn't worry about it. Even a hairline crack in a grain can allow
the flame-front through, so the separate grains (and their faces) will
ignite just fine. Even if they don't separate (due to the stiff fit),
the total pressure is determined by the total surface area that is
burning, and after the first few milliseconds these faces are burning
'away' from each other. So, in essence, there is no real 'need' for
them to actually center themselves (I'm sure it makes some minor
difference, but I don't think it will keep the motor from working). I'm
surprised that the grains were such a tight fit in the phenolic liner,
though -- can't say I've had that specific problem with the 29mm motors
(I've had problems with certain 38mm motors).
My guess is that the motor might 'chuff' a time or two at launch, as the
center core ignites and comes up to pressure with the faces igniting
shortly thereafter.
David Erbas-White
snipped-for-privacy@gmail.com wrote:
I'm glad to hear your surprised, this was my second "fit" problem with
the 29mm HP motors (I only assembled 3 so far, having problems with 2
out of 3 was not making me feel good about my choice in AT motors), the
first was the 29-240 and the liner just would not go in so I forced it
and destroyed it, AT offered me a replacement which was a much smoother
fit but it took over a month to get it, I ended up using 24mm LOC tube
as the liner, Thanks again :-), Le
No, no, no, a "significant" modification would be something along the
lines of using say, LOC 18mm or 29mm or even 38mm tube. That would be
significant!
:)
Is this place dead or what?
Looks like it's just me and you, Hilty.
'sup?
Went and looked at some chainsaws. Saw man I trust tells me no more
parts for my C5 homelite, so I need something to handle the light to
medium work so I can save the beastie for the big stuff. Opinions?
Dead as the proverbial doornail...
You forgot to start the thread up again with OT in the subject...
formatting link
Pick yer poison! Pound for pound, and dollar for dollar, IMHO, Stihl
beats anything. Well, maybe except the short-block chainsaw!
My father-in-law bought me this one a couple of years ago:
formatting link
I use it for brushing out a tree on the ground, and it's also so
wonderfully light that I can climb a tree and handle it easily with
one hand to prune, or drop storm damaged branches. I use the 12" bar.
My "middle" chainsaw's a Homelite XL. I use a 16", or 18" bar,
depending on what I'm cutting. It came with a 20" bar, but IMHO, it
really never had enough balls to run that bar and chain combo.
Then, of course, there's the "mother of all chainsaws" a Homelite
Model 45 with the 42" bar
You can't go wrong with Stihl tho' -- next time you see a professional
tree crew working (Davey, Asplundh, etc.), look at the brand of saw
their using. It's usually a Stihl.
tah
First place I looked. I replaced all my other yard equipment over the
last few years with Stihl (trimmer, weedeater, etc.) and based my
decision on the fact that Stihl is what you see on the lawn service
trailers. But I try to be open minded about purchases.
Isn't the 009 a little "light" (although I'm sure it's better than a
"Wildthing")? I was looking more at their midrange stuff, or maybe even
the 260. I don't like equipment that doesn't work, or requires work
from me to do work. Same reason I ended buying that Kubota garden
tractor and that rack of Stihl yard equipment.
Biggest thing that scares me with those little bitty saws is kickback.
The mighty C5 kicks back and moves about an inch, since it weighs about
as much as a small block. Little saws take off heads, arms and other
appendages.
How old is that XL, and how reliable has it been? Something about that
size is what I need.
How do you measure a bar, anyway? Total length? Length from the saw?
My C5 is 22" from the body of the saw to the tip.
A buddy of mine who used to work for a tree service that trimmed for
the utility companies swears by Poulan. Although, the company's
changed hands a few times. Dunno what the current quality's like, but
the "older" ones he has cut just as well as the Stihl's I've used.
Yeah, the 009's really little, but that's why I use it as my small
saw. When you're brushing out a 120 foot Maple, even the Homelite XL
gets to be pretty damn heavy after awhile. That little 009 is pefect
for cutting off all the little stuff in order to get to the logs with
the bigger saw.
Interesting. I've never had many issues with kickback. I mean, it's
happened a couple of times, but as I'm cutting, I just make myself
aware of the fact that it could happen when I'm cutting in a certain
situation. I've had more trouble with not properly gauging the
torque, or flex on a large branch that I'm cutting. I've gotten much
better over the years after being whacked upside of the head, nailed
in the shins, and banged in the thighs several times. After those
little "incidents" you tend to learn what to look out for extremely
quickly...
It's 10 years old this year, and honestly, I've never had a lick of
trouble with it. I get "razzed" quite a bit about owning it by many
of the other "heavy duty" woodcutting locals, but really, it's been
great. It fired up on the second pull last weekend when it was 15
degrees outside, and it had been sitting in the shed all week.
It's essentially the cutting area available on the bar -- so it
doesn't count the length of bar inside the powerhead. Generally, you
can measure from the tip of the circumference of the end to the bottom
of whatever enclosure that contains the sprocket. It does vary,
marginally, with the make of the saw.
This is fun!
tah
How high does your sprocket go and do you have to be certified?
Are you a member of the NCSA?
What's your number?
Are your papers in order?
SPEAK UP! Vee have vays of making you talk!
Randy
Motor assy. problems are common. Sometimes you have to peel the liner, or
the paper on the grains, or both. Phenolic liners can be sanded. Rattle
with some motors is normal. For example, the grains of an H-180 will rattle
when correctly assembled. What's important is to make sure the liner is the
correct length to seal the O-rings.
If you don't feel resistance when you tighten the rear closure, don't fly
it! *BOOM* will be the result.
tweak, which of the six things I mentioned should I have not mentioned
?
and hilty LOC and AT get the tubes from the same suplier, the liner and
the loc tube are identicle and even so, modifications are allowed where
I fly, but thanks for your input also :-) and Thanks Jerry for
reminding them they forgot to mention it was changed to off topic :-)
Le
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