How much sag is acceptable in a sawmill beam??

[betterbuilt]

Turbo. So my only question is why haven't you just said, bring it back we'll refund your money. It's that simple. He's not happy and drawing this out isn't helping anyone.

 

[steve easy]

So if turbo stands behind the product why is not them that makes the drive to kiwibros site? to offer solutions, advice or give him a refund, load the mill up and cut the ties, given its only "pocket change" as one member suggests. Be cheap customer relations.
Thumbs up to AS for allowing the thread to continue here, information good or bad about a product is helpfull to any potential customers.

 

[Turbosawmill]

I've offered to correct the beam. He just needs to send it back. If he wants a stronger beam we have one. He needs to spend the extra money and purchase one. If he wants it sold return it.

That's as far as I'm willing to go in this case.

Why? Kiwi has done everything possible to paint my company in the most negative terms on the net. Before attempting to work with us. Sure I believe it's fine as it is, never said I wouldn't sort it to his expectations though.

I could buy it back from him but really don't have an inclination to do that based his behaviour.

If he had come to us and chose to be open to solutions my support would be 100%

I have recieved nothing but negativity since he took the mill away.

 

[golddredgergold]

Problem is you guys are not getting all the info here about this topic that was already started by kiwi on the forestry forum and was locked down for good reason.

Kiwi has had the mill for some time now. Months and has gone past the window for asking for a return in my book. Now remember I have nothing to do with warrior sawmills in any way but I hate people crapping on business on the net due to they think they will gain something some how. I been on the bizz side of this myself before. Here is the good part. Kiwi is leaning all over a solid case of slander. Keep up the good work so when you go to court warrior can bring his counter suite and your threads and he will win as I did. You have dug a very deep hole kiwi.

Kiwi you are amazing bud. You have an answer for everything. Long drawn out with lots of big words. Just a genius. I am surprised you had to buy a mill when you have the knowledge you do you could have designed and built your own? Hell I am a simple weak minded pesant and I built my band mill.

Ok I am done now so kiwi go ahead and make a 500 word post responding to me. I will look forward to it. More of your time wasted rather than outside sawing. If it where not raining cats and dogs now that is where I would be rather than repling to this rubbish.

 

[Jim Timber]

Sounds like Turbo's made the effort commensurate to the deal Kiwi made for the saw. 5mm on rough sawn doesn't seem like that much to me. It's not bandmill straight, but it's also not bandmill portable (there's no equal from a BSM to the turbosaw's portability and wood handled - only other swing blades or CSM's), or BSM slow.

Comes down to either tweak it to be closer or sell it and be done. At some point the bitching is just bitching and not getting you anywhere. I can see both sides and while I'd probably be equally displeased by the dip. Might even have had a nasty email about it too, but this has dragged out for weeks and you're both backing into corners, which resolves nothing.

 

[KiwiBro]

Sounds like Turbo's made the effort commensurate to the deal Kiwi made for the saw. 5mm on rough sawn doesn't seem like that much to me. It's not bandmill straight, but it's also not bandmill portable (there's no equal from a BSM to the turbosaw's portability and wood handled - only other swing blades or CSM's), or BSM slow.

Comes down to either tweak it to be closer or sell it and be done. At some point the bitching is just bitching and not getting you anywhere. I can see both sides and while I'd probably be equally displeased by the dip. Might even have had a nasty email about it too, but this has dragged out for weeks and you're both backing into corners, which resolves nothing.

Heaps of good sense in that post Jim.
- Happy with trying the beam crowning to resolve the sag issues. Don't expect perfection.
- Unhappy with the bounce issues, symptomatic, I feel, of a beam that is just too soft and should never have been sold. Who'd buy a manual mill if they had to double pass 3" cuts and set up rails just to avoid bounce?
- Unhappy with myself for trusting and assuming rather than insisting upon real-world use of everything on the mill before parting with my $.

You are right, if Turbo won't refund, even with my offer to accept less $, then I either spend $ trying to sort this myself or sell the mill on and buy something else. The latter option I explored yesterday, which required another round of needlessly fractious emails with Turbo just trying to figure out what I can say about what they will be prepared to offer if by some outlandish stroke of poor luck there is another closed-minded, unreasonable buyer like me who themselves finds these issues unacceptable. Having finally reached some accord on that point with Turbo, I wrote up a draft for-sale listing for our major online sales site here in NZ called Trademe and am awaiting advice as to whether or not such an attempt to sell the mill like this will be wise in respect of my legal obligations around such things as representations, fitness for purpose, etc.

Quite apart from legal obligations, it's a bloody lousy feeling to feel shafted in a equipment purchase, and I'm not the type to do that to anyone else so I need to be sure my conscience is clear also. It's a tricky line to tread.

I should hear back today if I can cover myself legally while also exercising what I feel is a moral obligation I have to ensure buyers can make fully informed choices. Having read around the law on this a wee bit yesterday, I'm not hopeful I can escape liability in such a sale. For example, even if I put "as is where is" in the listing and had the buyer sign saying they accept such a term, it can still come back to bite me. The case law showed a car dealer did that on a cheapie, high mileage car sale, the buyer signed, the motor blew up a few months later (spat a con rod through the sump), and the dealer still had to not only refund but pay the buyers costs.

Like I said in a previous post, I've written off milling this Summer, and for my own mental state and after the advice of a good friend, I have taken a few days off to sort this crap out and look seriously at all my options before returning to work. Peak season and I'm tapping on my keyboard, calling lawyers who charge by the minute, researching stuff online, instead of burning dinosaurs and looking after customers who have been waiting for me since the end of last Summer.

 

[Jim Timber]

Turbo - if you're experiencing springing of the alloy beams, perhapse you could try filling the center with rigid foam? (like Great Stuff sold here in the states)

Aluminum has flex Kiwi. Aircraft wings flap long before they ever hold the weight of the plane. It's the nature of our physical world. Best way to dampen vibration is weight - you already said weight is an issue. No free lunch! But maybe Turbo's willing to let you be guinnea pig on a foam core beam. I think it might surprise you both.

 

[KiwiBro]

Turbo tried this and reported it didn't make enough of a difference to take it any further.

 

[Jim Timber]

How many types of foam did they try? There's dozens of durometers of two-part foams. Single part might not be stiff enough.

Foam has been used in lieu of wood to core downhill skis and snowboards for 25yrs. Certainly not because it's heavier or less rigid.

 

[Turbosawmill]

Hi Jim,

Thanks for your very constructive input. I had been meaning to test the foam theory for some time and finally did it last week.

We used a Sika 2 pot solution which filled and expanded very well.

My findings... It reduced deflection around .5mm however we did notice that it wasn't as springy as the standard beam. We are sending this foam filled beam to Australia - we will see how it reacts in Aus timber.

Mill bounce is evident on even the big mills such as our Gladiator (which has a giant beam 450mm x 450mm). Our big mill removes most it for most scenarios but will still get it in very hard timber sawing deep cuts. It's just something sawyers must deal with in one way or another. That's why there are devices available which offer solutions. Such as the options we provided to Kiwi which prevent both horizontal and vertical bounce independently.

If you do a little search on YouTube you will find bounce on almost every other swingblade depending on the timber being sawn. You'll see guys sitting on tracks and others just ignoring it.

It's pretty annoying to have this bounce so we've provided solutions.

 

[Jim Timber]

Something else to consider is prepreg carbon fiber formed with an air bladder to the inside walls of the beams. Probably won't do much for bounce, but could help a bunch with sag. Add foam in that and you might have something with enough benefit to justify the cost.

I'm not sure how expensive your extrusion lots are at the foundry, but adding internal ribbing would be something else to explore. You could probably modify your current die without needing to machine a new one.

Up here they'll run as little as $2k as a minimum extrusion.

Going to a higher silicon content in the alloy is another option yet, but weldability (post weld strength in particular) goes to crap with higher silicon, so if you need weldments it needs re-aging (which is another set of costs).

Some stuff to chew on anyway.

 

[Turbosawmill]

Thanks all makes since. Our target market is a low cost portable sawmill so the Carbon fibre scenerio puts a hefty price on a beam. Certainly if someone is willing to pay 5k just for the beam we will be happy to build it for them lol.

One of the main issues is our 6" model chainsaw mills sell for around $6500 the area of usable beam is limited. I have had done numerous FEAs on the beam design and currently it has a number of webs internally. Weight to strength is pretty good. We limited the beam weight to under 40kg in full length.

But moving up to the steel beam seemed to really solve all the issues. We have around 8 mill carriages currently sitting on a 7.2m beam at the factory and our deflection remains around 2-3mm. So this new beam with an 8" mill is going to be pretty impressive.

 

[Jim Timber]

Prepreg's not that expensive, but I'm basing that off our pricing/availability. Other places might not be as reasonable.

At any rate, at the end of the day we're still only rough sawing lumber, and surface finish is generally inversely proportional to rate of feed regardless of material being cut (wood, metal, or otherwise). You either accept it rough or need to slow down.

 

[Peterson Miller]

Maybe I am a "one in a million" case, but I have noticed very minimal (if any) bounce on my WPF Peterson mill, or any sag in the rails for that matter. Its just not there. I have watched pretty much every video Peterson have done on youtube and again, cant notice any bounce or sag either. Mind you, they have got track levelers and supports which probably eliminate the whole problem before it even happens...

 

[Turbosawmill]

Hi there Peterson Miller, Yes the WPF is a nice sturdy sawmill design (one of the more sturdy swingblades, the ground based tracks gives some nice advantages including extendable lengths). That's my sisters product lol.

Having said that I demonstrated these mills along the Australian coast from show to show and know for a fact I had to take wide iron bark cuts horizontally in 2 passes. Again its relative to the timber your sawing. Hence Petersons do offer an anti-bounce device, as do the others - in fact on some of the manufacturers videos you can actually see bounce just as the saw exits off the anti-bounce roller. So its real and out there lol.

As I understand it Kiwibro is sending his beam back to get crowned and also moving forward with the heavy duty beam. I'm keen to see if his story has the ability to be turned around.

 

[steve easy]

As I understand it Kiwibro is sending his beam back to get crowned and also moving forward with the heavy duty beam. I'm keen to see if his story has the ability to be turned around.

Im sure it can, or could have been done before it was dragged out here. Good on you Turbo.

 

[Peterson Miller]

Hi there Peterson Miller, Yes the WPF is a nice sturdy sawmill design (one of the more sturdy swingblades, the ground based tracks gives some nice advantages including extendable lengths). That's my sisters product lol.

Having said that I demonstrated these mills along the Australian coast from show to show and know for a fact I had to take wide iron bark cuts horizontally in 2 passes. Again its relative to the timber your sawing. Hence Petersons do offer an anti-bounce device, as do the others - in fact on some of the manufacturers videos you can actually see bounce just as the saw exits off the anti-bounce roller. So its real and out there lol.

As I understand it Kiwibro is sending his beam back to get crowned and also moving forward with the heavy duty beam. I'm keen to see if his story has the ability to be turned around.

Ah really, ha small world aye? hehe

Yeah my WPF doesnt have an anti bounce, I think I have seen it on the ATS model... I agree if you are cutting very hard wood like iron bark, then yes, it would be less stress on the blade and machine to take two bites. But on softwood like macrocarpa, pine etc? You should be able to do FULL cuts. And I don't mean a full 6 inch cut on an 8 inch machine, I mean a full 8 inch cut on an 8 inch machine. In fact I even saw a video the other week, on one of their mills cutting Jarrah wood which is an extremely hard Australian wood. I havent seen much about this mill, but apparently has been around for a couple years. Its the smallest one they make. Have a look.



I do have one question turbo: When there is sag in the beam on your mills, and you have to get the blade running true horizontally, where on the log do you base the measurement off? Because if its higher at the ends than it is in the middle (because of the sag), then your blade will constantly be wanting to dive or climb depending on how its adjusted, not so much on the 1 inch cuts, but definitely on the bigger cuts . That's how you lose tension in the blade.. as well as getting very weird sized boards. I would be interested to know how long the blades last on your machines as there must be so much force and friction on them from the sag on the mill. So are you going to be crowning all your beams now? And how much do you crown each beam, because you offer different engine sizes and different weights, different unit sizes (8 or 10"), different torque ratings, you would have to crown each beam on an individual basis because every one of the mills would be different I would think...

I notice on your website, you also have a gladiator with a 16m beam. I would assume you have crowned this because of the length and weight of the huge engine. Have you got any recent videos of it cutting a long log, doing full 12 inch cuts in one pass?

Sorry, that's more than one question! lol, it just got me thinking and now I am quite curious... Always liked a 12 inch mill, so the gladiator might be an option in the future as long as it doesn't have these issues.

Cheers

 

[Turbosawmill]

Peterson miller. Your looking a little to deep into a problem that's not there. Unless your string lining every setup with your WPF your going to have the very same issue that you've raised. I am guessing your not running a string line every setup against each track before running the saw. You'll probably be surprised at how much side bow may be evident on your main runner track (the one with single grooves).

It is after all timber. Fundamental requirement is equal thickness and accurate dimensioning. Simple.

Obviously excessive sag is a problem when you start noticing performance drop or blade heating but you'll be surprised to know that the beam would literally need to be an extreme banana before that would happen. Where as a bandsaw has a super fine and narrow blade, any dip would deviate the angle of the blade. Where as a circle mill would resist the dip.

Beam saws are very good at keeping the blade true while in the log - in fact much better than wide carriage/twin rail systems as the blade is kept straight on the single beam. There is no tendency to twist the saw as you push or pull. So I would expect a blade to last much longer on a beam saw (that's if we are splitting hairs).

Lots of hidden dynamics are happening when a saw moves through a log such as chain stretch from one end to the other or from side to side. A tensioned log may actually bow as you saw. So there is no magic formula with crown etc. a circular saw is very forgiving. We try and get our beam as straight as we can that's it.

FYI you'll notice that little JP sawing it's 6" in two passes ;-). That's a sweet advantage of having a swingblade sawmill.

Macrocarpa is easy cutting,
I agree a full 6" shouldn't be a problem for most higher priced mills. Not so sure on a full 10" though (if that's the model you have). Maybe you can show us one

No running against the collar either lol.

Cheers.
Jake

 

[Turbosawmill]

Missed your other questions... No we do not provide a crown typically. However if you choose you can crown our Gladiator beams at the centre just by adding washers at the join. The new 4-stroke heavy duty is also crown-able, as with our alloy beams. But we don't do this standard as its not needed. The nice thing with our saws is you can adjust the blade from the beam, so you don't really need to read the cut. Just measure from the beam to the front and back of your blade - very simple.

We are building a batch of mills right now (all with the heavy duty beams) so will get some footage of our 4-stroke units milling some hardwood to show off its resilience - I don't want people being confused between the superlight beam to our heavy duty standard kit (part of the package with our new larger GX690 4-stroke units).

https://www.facebook.com/1507538959...448217633466/1592446997633588/?type=1&theater

Gladiator sawing 12" wide horizontal cuts in one pass (around two weeks ago)...


Standard 4-stroke beam (3mm Pre-galv. lasered steel)...
http://turbosawmill.com/products/copy-of-8-cut-18hp-briggs-warrior-auto-sawmill

Our smaller 8" Warrior sawing Douglas Fur, full depth 8" vertical cut with light weight beam (around 14 minutes into it)...

 

[Haywire Haywood]

What is that extra side plate you had on Kiwi's mill? Is that a standard item or something you had put on extra?

Ian