How'd it go today?

[flushcut]

What if they made the torque specification based on not using anything?

Generally torque values are given in two specs: dry torque, and lubed torque. Dry values are much higher than lubed values. For instance my chipper bolts are 210ftlbs lubed but would be close to 350ftlbs dry. I use grease and have for a long time, never had a bolt get loose on me.

 

[lxskllr]

Finally found it in the manual. It was in the torque spec chart. It says all values are for dry, clean threads. It doesn't give lubricated values. 70#-80#

 

[Tree09]

Yeah that's not very tight then, that's not even enough for a 3" flange with a flexatalic gasket. How small of a bolt is that?

 

[lxskllr]

½"

 

[CurSedVoyce]

With a pretty nice spell of weather over the last week or so, only one rainy day in the last 8 days, M and I have been getting after a few items on the honey do list.

We replaced about 120 lineal feet of PT 2x6 decking on the back deck and a couple of 8 foot long by 12 inch wide treads on the front porch stairs. We generally have to replace a few boards every 5 or 6 years, but this year it was time for a bit more.

In one of those "why the hell have I not done this before...it has needed doing since we built this house in 1988!?" projects that ended up far simpler than I would have guessed, I cut out a 2'x3' rectangle of siding on the tall end of the porch skirting and built a door to access the underside of the porch. This will make replacing several boards on the porch decking easier, since I will need to sister some joists to simplify that job. One more trip to the lumber yard should do it for a few more 2x6's, and we can finish up the porch work later this week.

Good to get these projects done, and it has been straightforward and easy work in the bargain .

Thats on my list as well. Have to wait now. New 2x6. Front deck.

 

[Tree09]

Do those get the bolts through the knives? Mine just clamp it, no holes in the knives so if it loosens it could fly, a through bolt would likely fall out first (still bad, but the through bolt is likely safer). Can you get to the backside of the bolt? Is it a nut or a tapped hole? Mines a blind tapped hole in the drum (which also has the shaft going through it so it's just solid steel), and pulls an allen head bolt down on a tapered block, which clamps the knife, aka the worst possible thread repair you could attempt without large machine tools (which i have at this point but i still would hate to have to do it). Everything's at a wierd angle, the bolt is wayyyyyyy harder than the steel and any bits you have, the thing weighs several hundred pounds, nothing is flat for a mag drill, you may end up welding it shut then drilling and tapping it, you're into the main bearings likely, and when it's all said and done it has to be balanced again.

Because that's the possible consequence of a stuck bolt on my machine, I'm gonna use neversieze. Rain and tree matter will rust stuff up, and i don't wanna ever have to do that Every bolt on everything i repair gets neversieze, and i only fight bolts on stuff i haven't ever touched yet.

 

[Dave Shepard]

The Bandits were 180 ft lbs dry. Bolts went through the knife into the drum. If they were supposed to be lubed, I'm sure Paul would have spec'd it that way, being a stickler for details.

 

[lxskllr]

Do those get the bolts through the knives? Mine just clamp it, no holes in the knives so if it loosens it could fly, a through bolt would likely fall out first (still bad, but the through bolt is likely safer). Can you get to the backside of the bolt? Is it a nut or a tapped hole?

It goes through the knife with a hex head on top. You can access it through the hood.

 

[FireFighterZero]

Lazy day.

Picked up a 44 special at the local gunshow.

 

[stikine]

And there we have it... Jimbo saves the day from bolt anti-seize discussion. 😄

 

[Trains]

I'm liking this stuff.
View attachment 141803

Equal parts dx3 (atf) and acetone for the win.

your welcome.

 

[cory]

Jimbo saves the day from bolt antisiuze discussion. 😄

Not so fast-

09- as noted previously, when a bolt is tightened heavily, it stretches a tiny bit which allows it to do it's job but also means repeated tightening/loosening can weaken the bolt necessitating periodic bolt replacement.

If the bolt is the male member and the threaded hole in the chipper drum is the female part, isn't the threaded area in the drum/female part getting stretched too, so why doesn't it need periodic replacement?

 

[flushcut]

You replace it when the hole strips out lol

 

[flushcut]

Short answer is the threads are stronger than the bolt.
Threads get jacked up due to rust, being loose, and galvanic corrosion. Out of all the broken bolts you have ever seen in your life how many have stripped out the threads before the bolt itself has broke? Or how many times has the bolt sheared off inside a threaded hole?

 

[Tree09]

Very good question, and yes that's a consideration. The bolt is skinny while the tapped hole is in a thick section of solid steel, so basically the tapped hole wins until the threads strip, the bolt stretches while the block stays still. The tapped hole is also significantly deeper than a nut, so the force on the threads is less because there's far more threads engaged than a nut has.

 

[davidwyby]

I have seen threaded holes “pull” the steel around them up like a little volcano and keep parts from mating back up flat.

I replaced the thin block top deck engine in my mil truck with a thick deck because the studs can be cranked tighter and resist head gasket blowout better

 

[Nutball]

The total surface area of engaged threads is high compared to the cross section of the bolt, so the threads experience a lighter load while the length of bolt right under the head is going to experience the most movement being stretched (clamping force) and twisted from torquing it. Also, the female part has metal around it, and volume increases exponentially with diameter, so that side of things is not going to stretch as much.

 

[lxskllr]

Worked, shortened grass, and messed with the chipper. When I was looking up the torque specs, I noticed a note that said the disc should be greased after use, and if it isn't used for awhile, greased again, run, then greased yet again to prevent rust. Whoops. I didn't do all that, so I did it today. Also dragged the accusharp across the knives. Had to move the chipper to access the hopper where I keep all the stuff, so it's setup better in my drive now. I had too far back, and kind of cattywampus from the last time I had it out, and brought it back blind.

 

[Burnham]

I finished the under-the-porch access door today with final touchup painting and installation of the simple barrel latch to keep it snug. I'm pleased with the result.

Before that, M and I played chimney sweep for the new woodstove season, which is definitely upon us as the morning outdoor temps this week have been in the low 40's, and low 60's in the living room at coffee time. I did the rooftop work, and she cleaned the stove of the resulting creosote debris afterwards. Done and done.

 

[lxskllr]

I was thinking that myself, but didn't feel like getting on the roof today. I have time. It'll probably be mid November before the first fire, but time has a way of getting away from you. I want to get it done in the next couple weeks.

 

[Cobleskill]

Yup. Me too.

 

[cory]

The total surface area of engaged threads is high compared to ...

Threads are a rather facinating concept, their strength seems anti intuitive.

 

[Marc-Antoine]

It's mind blowing considering the fact that these little indents can hold such enormous loads.

 

[davidwyby]

Brush Fire in the mountains not too far from my moms but not close enough to worry much yet. Posta3 fire


112f today. Too hot for October, sick and tired of it and pretty much pissed off about it.

 

[Kaveman]

Played hooked and went and hiked up Mt Baldy today. Me and the new boots are quite well acquainted after 14 miles.