Re: Entire head coming down at an angle?
Mmmm yours is different from the picture on the manual. They usually do have a date of manufacture and so do the motors, you might look there No leaks, no gasket but it is sealed directly with silicone RTV - jv
On Mon, 18 Dec 2023, 8:15 am John Vreede via , <vreededesign= [email protected]> wrote: That's what you get for trusting the manual!? Boy are they useless. Of course that's?the reason groups like ours exist. Yours is definitely one of the old ones (manual is dated 2005) and should take 250ml OK. There is no reference mark that I?could give you to?fill too, because it?all?depends on how?far you lean it.?? I've fitted a clear plastic cover (3/8" thick Lexan) to the gearbox with fill and drain?holes (see pic).? The oil level when the sawframe is vertical, comes to the middle of the input shaft on both gearboxes when viewed from the side, which seems to leave enough air space.? I've only ever seen one of the new gearboxes (a 2017 RF128) and the outside of the gearbox casting was fluted. Maybe they produced?a new casting to differentiate their saw from the many Chinese saws then flooding the market and reduced the oil capacity at same time - jv ?
Well John,
I decided to follow your sage advise and wash out the grease from my gearbox, replacing it with the Heavyweight Shockproof oil.
I will need to order the oil as it seems it is not carried locally anywhere.
So, I boldly proceed to open the gearbox, prepared to become a greasy mess.
Sadly, as soon as I popped the cover, a whole bunch of oil dumped out on the floor !!!
Stupidly, I was so convinced by the statement in the manual that there was grease in there.? It did not even occur to me to tip the machine back so the gearbox would be horizontal.? It could have been worse (at least I had the saw in the horizontal position) !
The gears look brand new, but now I do not really have any idea how much oil remains and I can't just add some because I don't know exactly what it is.? So, I will proceed with the plan to drain and fill it with fresh Heavyweight Shockproof.? On the bright side, at least I don't have to get all greasy in the process and I know the gears look very good !!
I don't know how to gauge if this saw should be filled with 200 ml or 250 ml.? I'll just fill it with 200 and look at the level.? Roughly speaking, how close to the top of the gearbox should it be (assuming the gearbox is horizontal of course !!!)?
-Tom
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Re: Entire head coming down at an angle?
Here is what my gearbox looks like:  And, the nameplate:  I wish they would put the manufacture date on the nameplate.? I have no idea how long these were made.? I'm sure Grizzly would know the date based on serial number, but it's not really important.? As you can see it is Taiwanese. Do you have any leaks from your Lexan cover?
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Re: Entire head coming down at an angle?
Sorry didnt?answer your Q properly.? I don't know what the level would be if the gearbox was horizontal as it so unstable like that.? But if you put a piece of dressed 2x4 timber (~3 1/2") under the RHS leg (still v unstable!) the oil level comes to ~1/8"? from the edge of the?casting - jv
Well John,
I decided to follow your sage advise and wash out the grease from my gearbox, replacing it with the Heavyweight Shockproof oil.
I will need to order the oil as it seems it is not carried locally anywhere.
So, I boldly proceed to open the gearbox, prepared to become a greasy mess.
Sadly, as soon as I popped the cover, a whole bunch of oil dumped out on the floor !!!
Stupidly, I was so convinced by the statement in the manual that there was grease in there.? It did not even occur to me to tip the machine back so the gearbox would be horizontal.? It could have been worse (at least I had the saw in the horizontal position) !
The gears look brand new, but now I do not really have any idea how much oil remains and I can't just add some because I don't know exactly what it is.? So, I will proceed with the plan to drain and fill it with fresh Heavyweight Shockproof.? On the bright side, at least I don't have to get all greasy in the process and I know the gears look very good !!
I don't know how to gauge if this saw should be filled with 200 ml or 250 ml.? I'll just fill it with 200 and look at the level.? Roughly speaking, how close to the top of the gearbox should it be (assuming the gearbox is horizontal of course !!!)?
-Tom
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Re: Entire head coming down at an angle?
That's what you get for trusting the manual!? Boy are they useless. Of course that's?the reason groups like ours exist. Yours is definitely one of the old ones (manual is dated 2005) and should take 250ml OK. There is no reference mark that I?could give you to?fill too, because it?all?depends on how?far you lean it.?? I've fitted a clear plastic cover (3/8" thick Lexan) to the gearbox with fill and drain?holes (see pic).? The oil level when the sawframe is vertical, comes to the middle of the input shaft on both gearboxes when viewed from the side, which seems to leave enough air space.? I've only ever seen one of the new gearboxes (a 2017 RF128) and the outside of the gearbox casting was fluted. Maybe they produced?a new casting to differentiate their saw from the many Chinese saws then flooding the market and reduced the oil capacity at same time - jv ?
Well John,
I decided to follow your sage advise and wash out the grease from my gearbox, replacing it with the Heavyweight Shockproof oil.
I will need to order the oil as it seems it is not carried locally anywhere.
So, I boldly proceed to open the gearbox, prepared to become a greasy mess.
Sadly, as soon as I popped the cover, a whole bunch of oil dumped out on the floor !!!
Stupidly, I was so convinced by the statement in the manual that there was grease in there.? It did not even occur to me to tip the machine back so the gearbox would be horizontal.? It could have been worse (at least I had the saw in the horizontal position) !
The gears look brand new, but now I do not really have any idea how much oil remains and I can't just add some because I don't know exactly what it is.? So, I will proceed with the plan to drain and fill it with fresh Heavyweight Shockproof.? On the bright side, at least I don't have to get all greasy in the process and I know the gears look very good !!
I don't know how to gauge if this saw should be filled with 200 ml or 250 ml.? I'll just fill it with 200 and look at the level.? Roughly speaking, how close to the top of the gearbox should it be (assuming the gearbox is horizontal of course !!!)?
-Tom
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Re: Entire head coming down at an angle?
Well John,
I decided to follow your sage advise and wash out the grease from my gearbox, replacing it with the Heavyweight Shockproof oil.
I will need to order the oil as it seems it is not carried locally anywhere.
So, I boldly proceed to open the gearbox, prepared to become a greasy mess.
Sadly, as soon as I popped the cover, a whole bunch of oil dumped out on the floor !!!
Stupidly, I was so convinced by the statement in the manual that there was grease in there.? It did not even occur to me to tip the machine back so the gearbox would be horizontal.? It could have been worse (at least I had the saw in the horizontal position) !
The gears look brand new, but now I do not really have any idea how much oil remains and I can't just add some because I don't know exactly what it is.? So, I will proceed with the plan to drain and fill it with fresh Heavyweight Shockproof.? On the bright side, at least I don't have to get all greasy in the process and I know the gears look very good !!
I don't know how to gauge if this saw should be filled with 200 ml or 250 ml.? I'll just fill it with 200 and look at the level.? Roughly speaking, how close to the top of the gearbox should it be (assuming the gearbox is horizontal of course !!!)?
-Tom
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Re: Older Rongfu RF-115 bansaw details required
toggle quoted message
Show quoted text
Made some progress-Photos
Need to do:
1-Wire electrics so it shut off with reset electrically like mill or lathe(Relay hold).
2-To obtain correct blade and start setting it to saw accurately, whatever it takes.
3-To make/design a heavy backstop for whole lid + bandsaw contraption to hold it the bandsaw vertically(Not the saw vertical like when you want to saw vertical), this is to hold the bandsaw vertically out of the way of compressor lid so the stainless tray can be used with lathe if needed, otherwise a small tray at end over this one is used.
4-Minor mods to compressor sides and painting. 
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Re: Older Rongfu RF-115 bansaw details required
Nice one Dave! It looks?like you need a gas strut to support that lid/saw combo (like from a Hatchback car).? They come in all different lengths and poundages from McMaster Carr or similar - jv?
Made some progress-Photos
Need to do:
1-Wire electrics so it shut off with reset electrically like mill or lathe(Relay hold).
2-To obtain correct blade and start setting it to saw accurately, whatever it takes.
3-To make/design a heavy backstop for whole lid + bandsaw contraption to hold it the bandsaw vertically(Not the saw vertical like when you want to saw vertical), this is to hold the bandsaw vertically out of the way of compressor lid so the stainless tray can be used with lathe if needed, otherwise a small tray at end over this one is used.
4-Minor mods to compressor sides and painting. 
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Re: Entire head coming down at an angle?
Hi Tom Worn blades definitely can 'lead' (as the wood bandsaw?people call it), but all the new blades I've ever measured cut in the same direction as the blade body points.? Most blades that have been used still cut straight, but if you blunt one side of the blade wrt the other, like cutting through the heat affected zone of a weld (even in mild steel!), it will 'lead' ever after. For all the effort?involved to adjust the saw to cut square, it pays to use a new blade.? If afterwards the old blade cuts square?too, then you've got 2 good blades. I've got 3 saws and 2 of them had non-parallel pivot shafts, one was a little worse than yours, the other about the same. I figure at least 50% of 4x6's have this fault. It never ceases to amaze me that such a fundamental?aspect of the construction of these saws is gotten so wrong by so many different manufacturers. For the rest of it, it is so adjustable?(too adjustable!) that any inaccuracies can be compensated for, but until Mark Kimball found this correction method, you had to do more machining work than the saw was worth to fix it. If you haven't already done it, changing the oil is a must, even for new saws (around 2007 some saws were delivered with casting sand in the gearbox oil! - though that hasn't been reported for a while). Many people have reported gearbox failure (brass gear almost always is the one to fail) but I think most will have been from misalignment of the worm and wheel or a burr which cuts the brass to shreds rather than lubrication failure. Worm drive gearboxes like the 4x6 are high friction devices where the load on the teeth is from sliding friction.? Also ours is running slowly compared to normal worm gearbox standards, giving?time for the lubricant to be squeezed out and allowing metal to metal contact to wear the gears . Grease is a high viscosity lube but I'm sceptical?that enough of it would be in the right place if the saw is run for any length of time.? I don't know of any industrial worm drive?gearboxes being grease lubed but know of plenty of sealed-for-life worm 'boxes running synthetic lubricants. From the running speed and load the?correct viscosity GEAR oil is SAE 140.? It is my guess that your 'box?has grease from the manufacturer,?because that way Grizzly gets less complaints about oil leaks.... (Its called Value Engineering - though value to whom and for what is unclear except that it's not you that is the beneficiary).? I'd wash out the grease with petrol and replace?with oil as below. From testing I've done (timing how long it took the gearbox to reach 65C (150F) when cutting continuously), the best oil I've tested in this regard was Red Line 75W-250 'Heavyweight Shockproof' oil.? It has about the same viscosity as straight 140 weight oil at ~40C (100F) which is the temperature home shop use?would get the oil to (unless you live in the frozen north where the Red Line 75W-140 'Lightweight Shockproof'? would be better). All Red Line lubricants are 100% synthetic and if you use one or other of these 2 - you need not change the lubricant for the life of the saw however much you use it.? That said, any good 'yellow metal safe' SAE140 gear oil (not motor oil as the SAE scale for motor oils is completely different) will be OK for intermittent use.? I recently overhauled a 35 year old RF115 saw for a friend which had only 60ml oil left in the 'box (of the 200ml it should have had) and the gears were still in very good condition. Gear oils formulated for sliding friction use (hypoid) need extreme pressure additives, which GL4 and GL5 rated oils have.? GL4's are known to be 'yellow metal?safe' i.e. for the?brass pads on the synchromesh?cones of manual automobile gearboxes (which operate at ~90C (200F). GL5 rated oils have higher levels of the same EP additive and when introduced were found to cause gearbox problems. These early? EP additives used to break down into acid components?that would eat away at the zinc?in the brass, but nowadays they're 'buffered' or 'deactivated'. I tested a buffered GL5 oil by putting a polished piece of brass into it and held it at 35C (95F) for a year on the top of my hot water cylinder - it came out as polished as it went in, though the bit exposed to the air was tarnished! There is no issue with buffered GL5 oils being used in 4x6 gearboxes.?? Oil volume also affects wear: the more oil the better.? About 250ml of oil will?fit into a std 4x6 gearbox if you lay it over when filling, BUT if you run the saw continuously and get to temperatures of 50-65C (120-150F) then late model saws(from about 2010), which have a smaller gearbox volume, pressurize the air space in the gearbox too much and will blow oil out the seals if they contain more than 200ml.? If you don't run that?hot or have an older saw use 250ml.
John:
Thanks for readdressing this issue !
Your points all seem well reasoned and I do like the alternate method that you propose.? In fact, while playing with my saw, I was effectively doing just that by placing shims under the engineers square until the blade just skimmed the square the whole distance.? I do agree that actually cutting, and averaging multiple cuts makes a lot of sense.
There is a certain risk in cutting because it is quite possible for a blade to not cut straight because of worn / damaged teeth so perhaps it is best to use a new blade when doing this procedure.? I do have a new blade, and I will also compare methods as a cross check...? It goes along with the old adage - Measure twice, cut once !
I did this pretty quickly, and plan to spend more time being meticulous, but it looked like my pivot was off by about 0.062" (a 1/16" shim under the square was very close).? It was visually obvious as soon as I moved the arm with the square in place.? If this turns out to be correct, I am curious where it falls in the spectrum of these machines.? I do have a metal lathe, and will probably make a new shaft using the lathe when the time comes.? I am not sure how old this one is (the G1010 is no longer produced) but it is in very good condition.
Finally, do you have an opinion about grease vs. oil in the gearbox?? The Grizzly manual specifies grease.? I did see a post in this forum (maybe yours) about a wide variety of different oils.? I am tempted to follow Grizzly's instructions in the manual.? It seems to me that you would design the gearbox differently for oil vs. grease.? I am just a home hobbyist, so the saw will be used infrequently.
-Thanks
?Tom
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Re: Entire head coming down at an angle?
John:
Thanks for readdressing this issue !
Your points all seem well reasoned and I do like the alternate method that you propose.? In fact, while playing with my saw, I was effectively doing just that by placing shims under the engineers square until the blade just skimmed the square the whole distance.? I do agree that actually cutting, and averaging multiple cuts makes a lot of sense.
There is a certain risk in cutting because it is quite possible for a blade to not cut straight because of worn / damaged teeth so perhaps it is best to use a new blade when doing this procedure.? I do have a new blade, and I will also compare methods as a cross check...? It goes along with the old adage - Measure twice, cut once !
I did this pretty quickly, and plan to spend more time being meticulous, but it looked like my pivot was off by about 0.062" (a 1/16" shim under the square was very close).? It was visually obvious as soon as I moved the arm with the square in place.? If this turns out to be correct, I am curious where it falls in the spectrum of these machines.? I do have a metal lathe, and will probably make a new shaft using the lathe when the time comes.? I am not sure how old this one is (the G1010 is no longer produced) but it is in very good condition.
Finally, do you have an opinion about grease vs. oil in the gearbox?? The Grizzly manual specifies grease.? I did see a post in this forum (maybe yours) about a wide variety of different oils.? I am tempted to follow Grizzly's instructions in the manual.? It seems to me that you would design the gearbox differently for oil vs. grease.? I am just a home hobbyist, so the saw will be used infrequently.
-Thanks
?Tom
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Re: Entire head coming down at an angle?
Hi Tom You're correct that the blade is square to the saw table, even when it's moving in a non-square arc due to the pivot shaft not being parallel to the saw table, but you have forgotten about the set of the teeth. The set enables the cut surface to accurately?mirror the movement of the blade without deflecting the blade body as implied by your drawing. I agree that the gap between blade and setsquare is an accurate?representation of the tilt of the pivot shaft and the saw table BUT you will find (as I did when I tried it way back) that measuring the gap is way more difficult than it seems. The most inaccurate part of the measurement is assessing?the 'feel' of the feeler gauge between the upper end of the setsquare blade and the sawblade, as the blade will perceptibly deflect with?very little pressure leading to over measuring and hence over correction.?? Cutting test pieces from the S4S timber allows the following benefits - repeatable production of test-pieces
- standardized measuring with a micrometer or digital caliper
- the test piece is produced by actually cutting something (not an inference from a secondary related process)
- It is very very sensitive, allowing you to creep up on the point where the pivot shaft becomes parallel to the saw table to an accuracy of 0.002" difference between each end of the test piece 4" long (0,05mm in 100mm) where saw? manufacturers?consider? 0.012" in 4" to be 'effectively square'
Can I suggest an alternative to measuring the gap between the blade and a set square: - Find a feeler gauge?set from which you can remove the leaves (Mitutoyo and others do one with a thumbscrew tightening the friction between the leaves)
- Stack appropriate leaves under one end of the S4S timber to tilt it, at the edge of the saw infeed table (which end depending on which way the pivot shaft is tilted), until the test pieces?saw off parallel as measured with the micrometer or digital caliper??
- The angle is then the stack height over the distance from where the S4S timber is tilted.
- When you think you've got the stack thickness correct, cut about 3-5 more identical test pieces to verify that its correct (always take 10sec+ to make a cut in wood or the teeth gullets overload and it cuts in a curve)?
- To? find the amount that must be removed from the pivot shaft, multiply the stack height by the distance between pivot shaft ears on the base casting, divided by the saw infeed table width??
Effectively it is the same measurement you propose but made in a repeatable fashion. In fact?this can be turned?into a quick and dirty fix - fixing an equivalent thickness of metal, to the stack height, in that place with double-sided?tape (the tape I used was 0.003" thick in itself?and must be accounted for). This works for lengths of stock to be cut that are greater than saw infeed table width. Worked?for me until I got the time to fix it for good - jv??
Good Evening,
I know it has been a while since addressing this topic, but I just bought a used Grizzly G1010 4x6 and I wanted to align it before starting to use it.
I spent a LOT of time reading through this forum and I want to compliment all of you on the excellent work you have done here.
I am specifically interested in the vertical alignment discussed here, and especially John's paper:
"Fixing vertical squareness or Worn pivot bearings on a 4x6 Bandsaw v2.pdf"
This paper is excellent, and I have discovered that my table is very smooth and flat.
But I do have an issue with the pivot not being parallel to the table (to the tune of around 1/16").
While learning about this, I made a simple CAD model shown here:
If you look at this model from the front (facing the vise wheel), it looks like this...
(you can see as the blade goes up, it remains perfectly square, always aligned with the engineer's square):
Now, if I look at the same view, but with a tilted pivot...
the blade travel moves away from the square (by around 1/8" in this illustration):
I love the way you guys have come up with to fix this by machining / filing the pivot pin.
There is one thing that bothers me however, and I would like to get your opinions...
The issue relates to the technique of using the 1x4 S4S test board to determine the necessary offset for machining.
If you look carefully at the blade path with and without an offset, you get this:
 ?
Notice that with the tilted pivot, the blade drifts to the side (1/8" in this example), but it is important to note that the blade itself is always vertical.? This is because everyone (rightly so) adjusts the blade guides so the blade is vertical.? What this means is that when you are doing a test cut, the blade will want to cut vertically (as all good band saw blades do), but it is drifting to the side because of the tilted pivot.? Doesn't this mean that the test cuts are not really correct and may tend to be curved or otherwise inaccurate?
It seems to me that it might be better to not use test cuts because of this effect, and rather, just measure the gap between the blade and the engineer's square over a 5" distance (which corresponds to the pivot bearing spacing).? This measurement seems more direct, simpler and is not subject to any error from a blade that is being forced sideways by the tilted pivot during the test cut(s).
When I try to correct this I will start with a new pivot shaft, and the beauty of this technique is that nothing is being modified with the saw (other than adding a grub screw) so if a mistake is made, it is easy to revert back to the original setup.
Does you agree with me that this sideways drifting has an impact on the accuracy of the test cut method of measurement?
-Tom
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Re: Entire head coming down at an angle?
Good Evening, I know it has been a while since addressing this topic, but I just bought a used Grizzly G1010 4x6 and I wanted to align it before starting to use it. I spent a LOT of time reading through this forum and I want to compliment all of you on the excellent work you have done here. I am specifically interested in the vertical alignment discussed here, and especially John's paper: "Fixing vertical squareness or Worn pivot bearings on a 4x6 Bandsaw v2.pdf" This paper is excellent, and I have discovered that my table is very smooth and flat. But I do have an issue with the pivot not being parallel to the table (to the tune of around 1/16"). While learning about this, I made a simple CAD model shown here:  If you look at this model from the front (facing the vise wheel), it looks like this... (you can see as the blade goes up, it remains perfectly square, always aligned with the engineer's square):  Now, if I look at the same view, but with a tilted pivot... the blade travel moves away from the square (by around 1/8" in this illustration):  I love the way you guys have come up with to fix this by machining / filing the pivot pin.
There is one thing that bothers me however, and I would like to get your opinions... The issue relates to the technique of using the 1x4 S4S test board to determine the necessary offset for machining. If you look carefully at the blade path with and without an offset, you get this:  ? Notice that with the tilted pivot, the blade drifts to the side (1/8" in this example), but it is important to note that the blade itself is always vertical.? This is because everyone (rightly so) adjusts the blade guides so the blade is vertical.? What this means is that when you are doing a test cut, the blade will want to cut vertically (as all good band saw blades do), but it is drifting to the side because of the tilted pivot.? Doesn't this mean that the test cuts are not really correct and may tend to be curved or otherwise inaccurate? It seems to me that it might be better to not use test cuts because of this effect, and rather, just measure the gap between the blade and the engineer's square over a 5" distance (which corresponds to the pivot bearing spacing).? This measurement seems more direct, simpler and is not subject to any error from a blade that is being forced sideways by the tilted pivot during the test cut(s). When I try to correct this I will start with a new pivot shaft, and the beauty of this technique is that nothing is being modified with the saw (other than adding a grub screw) so if a mistake is made, it is easy to revert back to the original setup. Does you agree with me that this sideways drifting has an impact on the accuracy of the test cut method of measurement? -Tom
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Re: Homemade Bandsaw Blade Welder
Hello, and sorry for revamping this way old thread.
I'm in search of some welder plans but it seems the one at ?is not more reachable.
Is there any chance that someone has saved the pdf and would like to share ?
I'm not at all good in electronic, so the one from harold strand ( the one is easy tofind in internet ) is not good for me ( is for 115V and I'm in a 220V country ).
Thanks
Pierluigi
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Re: Older Rongfu RF-115 bansaw details required
Hi Chris Sorry I took so long to reply, been out of the loop just lately. Bill has the right of it, the play in the guides/tensioner guide block gets pulled out when the blade is under tension and the whole assembly goes rigid.? Mine is as loose as too and that has no effect on the cutting If your saw is throwing blades when in the cut, that's more likely to do with the lower (drive) bandwheel, not the upper (driven) one.? The rear support roller that pushes the blade/teeth into the cut is likely too far forward.? If the bearing bracket, that carries both the rear and side guide rollers (those ball bearing races),?has been adjusted too far forward on the tongue?and groove joint (between the bearing bracket and the support arm), when the weight comes on in the cut that lower rear roller acts as a pivot to lever the blade off the drive? wheel. So the blade will track OK when not in the cut but pops off when it is cutting, Can take a few revolutions of the blade before it comes off, but you can see it slowly derail if you look where the blade rides on the drive bandwheel. - jv?
[Edited Message Follows]
Thanks for the info, the all play is what I wanted to know about. The blade tightning I can control by tightning it, the blade tilt I can control by adjusting a bolt & grubscrew, however the play thats in the direction not covered by above adjustments I have no way to control.
Your experience is good to know.
I did an experiment and will know later on if it bad or good outcome when I actually saw with it. I got this bandsaw because it thrown blades. It seems the previous owner replaced the slave wheel bush, which is new and has no play, I just made a proper spacer to take out the endplay here. I also corrected the main wheel/gearbox bearing assembly to the best of my ability. If it stay put when in use what I have done will be the selution.
Temp Mod(Experiment):I decided to make two new plates at slave wheel a bit thicker and milled down, so that it slide with zero play, busy today with this. When in use I will know if this mod was any good, if not I revert back to original plates. With this zero play, I can still adjiust the blade tention, and the blade tilt, just from a zero play base.
On Thu, Nov 30, 2023 at 1:16?AM Bill Armstrong < bill_1955@...> wrote:
I have a Grizzly 5 x 6, and with the blade removed, the idler has play all over the place. Pick a axis, it moves in any. It all goes away once you install the blade and tighten it, and has never been a problem in the 15+ years I’ve had the saw. ?
?
Other Bill
?
[Edited Message Follows]
Previously:
I made a bracket that swivel on top of compressor(Silenced) cabinet, of which in turn the top can open up like a car bonnet to access compressor parts to remove/repace when needed. The bansaw in turn can swivel up and vertical out of the way to reveal a top stainless steel tray for use if needed.
Installing the bansaw(Refurbishing) on top of compressor:
Hi, back at the bandsaw. I would like to know about the play in the slave wheel alignment adjustment device. I understand the Tention of the blade adjustment and movement, as well as the Blade Tilt adjustment with fasteners "C & "B" in photo edited it swivel around "A".
Problem:Play in Blade tilting device I cannot adjust, is it normal or a problem-?
<0_Play-AdjustableFrontWheelDevice.jpg>
?
What I don't understand is the amount of play up/down as indicated in purple when you pull up & down on pulley or pully shaft with pulley removed. I would say mine has excessive play here, which I cannot adjust. Before I make some mods with milling machine, I would like to hear your opinion around this-?
Thankyou
Chris
?
?
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Re: Older Rongfu RF-115 bansaw details required
I have a Grizzly 5 x 6, and with the blade removed, the idler has play all over the place. Pick a axis, it moves in any. It all goes away once you install the blade and tighten it, and has never been a problem in the 15+ years I’ve had the saw. ?
toggle quoted message
Show quoted text
On Nov 29, 2023, at 1:54 PM, Hettie Chom <hettiechom@...> wrote:
?
[Edited Message Follows]
Previously:
I made a bracket that swivel on top of compressor(Silenced) cabinet, of which in turn the top can open up like a car bonnet to access compressor parts to remove/repace when needed. The bansaw in turn can swivel up and vertical out of the way to reveal a
top stainless steel tray for use if needed.
Installing the bansaw(Refurbishing) on top of compressor:
Hi, back at the bandsaw. I would like to know about the play in the slave wheel alignment adjustment device. I understand the Tention of the blade adjustment and movement, as well as the Blade Tilt adjustment with fasteners "C & "B" in photo edited it swivel
around "A".
Problem:Play in Blade tilting device I cannot adjust, is it normal or a problem-?
<0_Play-AdjustableFrontWheelDevice.jpg>
What I don't understand is the amount of play up/down as indicated in purple when you pull up & down on pulley or pully shaft with pulley removed. I would say mine has excessive play here, which I cannot adjust. Before I make some mods with milling machine,
I would like to hear your opinion around this-?
Thankyou
Chris
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Re: Older Rongfu RF-115 bansaw details required
Alrighty then , let me be sure I understand what you think the problem is . If I'm understanding you , the guides that the block slides in/on are loose and sloppy . Draw a line from center of top wheel to center of bottom wheel . Let's designate this line as "X axis" . Is the front guide block rotating in this X axis ? I think this is what you mean with the purple circle and arrows in your picture ?
--
Snag
Men don't protect women because they're weak .
We protect them because they're important .
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Re: Blade guide modification
Nice job , yer gonna get a whole lot less flexing out of those
parts .
Thanks for sharing
animal
On 10/20/23 8:03 PM, Mark Kimball
wrote:
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Show quoted text
I've had a problem with getting good vertical blade alignment for
quite awhile now.? In that, while I can get the blade vertical, it
also is displaced.? In other words, it doesn't have just pure
twist, it's pushed to one side or the other.? This makes it
difficult to get proper alignment in the other axis, and also
leads to strange interactions between blade tension and blade
tracking.
I did some testing by clamping a short length of aluminum flat
stock to the blade and then used it to twist the blade so it was
exactly vertical (this was done with the blade guide assemblies
removed, but the mounting brackets were still installed).? This
showed me how far off the 8mm screw holes for the blade guide
assemblies were, since they should be more-or-less in line with
the aluminum flat.? I observed a number of things that were
wrong.? For the bottom blade guide bracket, the 8mm hole was in
line (this was good), but the dovetail boss wasn't parallel to the
bar.? It was so far off that it was impossible to adjust the blade
guide to avoid moving the blade around in order to get the blade
vertically aligned.? I also found that the upper blade guide
bracket's 8mm hole did NOT line up with my aluminum bar, so it,
too, would cause the same problem.? Now, it would be possible to
machine the bottom support bracket to improve the situation but
that wasn't going to work with the upper bracket.? Plus, I really
didn't want to modify the OEM brackets, just in case something
went wrong.
For these reasons I decided to make two replacement blade guide
brackets.? I had originally considered making a trunnion-like
arrangement that would only permit adjustments around the
blade-neutral axis, to get nothing but twist, no displacement --
but that was getting complicated and looked like it would require
making new blade guides, too.? Instead, I came up with a
relatively simple change to the OEM blade guide brackets that
would add additional adjustment range, enough to produce something
a lot like the trunnion scheme.
The following photos show a lot of what I did to accomplish this.?
FYI, the replacement mounting brackets consist of two parts.? One
is the vertical part (when the saw frame is vertical), which is
bolted to the saw frame; and the second is the support piece,
where the blade guide with its three ball bearings is attached.
This photo shows the lower vertical part, after marking the
location where the OEM bracket's 8mm hole intersected the aluminum
bar when twisting the blade for verticality.? I used this to
(eventually) determine where the horizontal support piece needed
to be attached.? The 8mm screw hole actually is centered on the
edge of the vertical bar, but this isn't an issue because the 8mm
mounting hole will be drilled/tapped in the horizontal piece.
The piece below is the horizontal piece.? I drilled/tapped an 8mm
screw hole centered on one axis, and .350" from the left edge (MK2
version, mentioned below).? This hole is used to mount the blade
guide assembly.
I aligned the piece so its 8mm hole was over the mark on the edge
of the vertical part, and rotated it so its long axis was parallel
to the aluminum bar when the blade was twisted to get proper
vertical alignment, then used a sharpie to draw the outline of the
vertical piece.? This was used to determine where I needed to
drill the mounting hole for screwing the horizontal and vertical
pieces together.
The photo below shows the two pieces screwed together, from a side
view.
The photo below shows the assembly from the top.? Note that the
horizontal piece looks a bit different.? It is the "MK2" version,
after I learned a few things.? The rounded corner is there to
provide clearance between the saw blade and the mount piece.? A
nice benefit of using this two-piece approach is that I can rotate
the top horizontal part, providing additional adjustment range.
The additional adjustment range works pretty well, at least on my
bandsaw.? Here's a photo showing the current setup, looking down
the blade toward the two blade guides:
The result is a vertical cut that is pretty good.? And I didn't
have to do much adjustment to get the work-holding vise at 90
degrees to the blade, either.
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I've had a problem with getting good vertical blade alignment for quite awhile now.? In that, while I can get the blade vertical, it also is displaced.? In other words, it doesn't have just pure twist, it's pushed to one side or the other.? This makes it difficult to get proper alignment in the other axis, and also leads to strange interactions between blade tension and blade tracking. I did some testing by clamping a short length of aluminum flat stock to the blade and then used it to twist the blade so it was exactly vertical (this was done with the blade guide assemblies removed, but the mounting brackets were still installed).? This showed me how far off the 8mm screw holes for the blade guide assemblies were, since they should be more-or-less in line with the aluminum flat.? I observed a number of things that were wrong.? For the bottom blade guide bracket, the 8mm hole was in line (this was good), but the dovetail boss wasn't parallel to the bar.? It was so far off that it was impossible to adjust the blade guide to avoid moving the blade around in order to get the blade vertically aligned.? I also found that the upper blade guide bracket's 8mm hole did NOT line up with my aluminum bar, so it, too, would cause the same problem.? Now, it would be possible to machine the bottom support bracket to improve the situation but that wasn't going to work with the upper bracket.? Plus, I really didn't want to modify the OEM brackets, just in case something went wrong. For these reasons I decided to make two replacement blade guide brackets.? I had originally considered making a trunnion-like arrangement that would only permit adjustments around the blade-neutral axis, to get nothing but twist, no displacement -- but that was getting complicated and looked like it would require making new blade guides, too.? Instead, I came up with a relatively simple change to the OEM blade guide brackets that would add additional adjustment range, enough to produce something a lot like the trunnion scheme. The following photos show a lot of what I did to accomplish this.? FYI, the replacement mounting brackets consist of two parts.? One is the vertical part (when the saw frame is vertical), which is bolted to the saw frame; and the second is the support piece, where the blade guide with its three ball bearings is attached. This photo shows the lower vertical part, after marking the location where the OEM bracket's 8mm hole intersected the aluminum bar when twisting the blade for verticality.? I used this to (eventually) determine where the horizontal support piece needed to be attached.? The 8mm screw hole actually is centered on the edge of the vertical bar, but this isn't an issue because the 8mm mounting hole will be drilled/tapped in the horizontal piece.  The piece below is the horizontal piece.? I drilled/tapped an 8mm screw hole centered on one axis, and .350" from the left edge (MK2 version, mentioned below).? This hole is used to mount the blade guide assembly. I aligned the piece so its 8mm hole was over the mark on the edge of the vertical part, and rotated it so its long axis was parallel to the aluminum bar when the blade was twisted to get proper vertical alignment, then used a sharpie to draw the outline of the vertical piece.? This was used to determine where I needed to drill the mounting hole for screwing the horizontal and vertical pieces together.  The photo below shows the two pieces screwed together, from a side view.  The photo below shows the assembly from the top.? Note that the horizontal piece looks a bit different.? It is the "MK2" version, after I learned a few things.? The rounded corner is there to provide clearance between the saw blade and the mount piece.? A nice benefit of using this two-piece approach is that I can rotate the top horizontal part, providing additional adjustment range.  The additional adjustment range works pretty well, at least on my bandsaw.? Here's a photo showing the current setup, looking down the blade toward the two blade guides:  The result is a vertical cut that is pretty good.? And I didn't have to do much adjustment to get the work-holding vise at 90 degrees to the blade, either.
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Correction in 1st paragraph: .... not parallel to the blade.?
On Sun, 17 Sep 2023, 7:16 am John Vreede via , <vreededesign= [email protected]> wrote: Hi? Mark The human eye is pretty damn good at seeing squareness and parallelicity so I don't doubt that groove in the bracket seat is not parallel to the arm it slides on. I've seen it on ones I've dealt with too.? Unfortunately the parts are not made with much precision. I believe the manufacturers build in so much slop (they call it 'adjustability') that you can mostly get it adjusted correctly, but I've had to file the corners of a bracket tongue to get enough twist to align a blade vertical on a brand new machine. For the purposes of your drawing the assumption that they should be parallel is correct - jv
Hi John,
The 40 degree angle is closer to what I measured when I looked at the angle between the blade guide support's square dovetail and its body.? That's part #84 in my Harbor Freight owner's manual.? It's called the "lower blade guide bracket seat" in my manual.? But I wasn't sure if the plane of the bracket seat's body is anywhere close to vertical (when the body frame part #62 is horizontal).? Apparently it is.
I also saw that when the blade is twisted to be vertical the plane of its wide dimension passes through the M8 hole in the bracket seat.? That makes a lot of sense!? However, it doesn't seem to be exactly parallel to the long axis of the dovetail.? ?Maybe that's to account for the necessary clearance between the saw blade and guide bearings?? With zero clearance the blade and guide bearing axes would be parallel, but adding clearance would result in needing some additional "twist offset" on the part of the blade guide.? More clearance = more angular offset.? But how large is that angle?
Knowing that the bearings are 9mm long, for .005" clearance I calculate less than 1 degree. .010" would come to 1.6 degrees.? Not much to worry about I'd say.? So the dovetail alignment issue may be an observation error on my part (I just eyeballed it), or perhaps a minor design error.
Mark
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Hi? Mark The human eye is pretty damn good at seeing squareness and parallelicity so I don't doubt that groove in the bracket seat is not parallel to the arm it slides on. I've seen it on ones I've dealt with too.? Unfortunately the parts are not made with much precision. I believe the manufacturers build in so much slop (they call it 'adjustability') that you can mostly get it adjusted correctly, but I've had to file the corners of a bracket tongue to get enough twist to align a blade vertical on a brand new machine. For the purposes of your drawing the assumption that they should be parallel is correct - jv
Hi John,
The 40 degree angle is closer to what I measured when I looked at the angle between the blade guide support's square dovetail and its body.? That's part #84 in my Harbor Freight owner's manual.? It's called the "lower blade guide bracket seat" in my manual.? But I wasn't sure if the plane of the bracket seat's body is anywhere close to vertical (when the body frame part #62 is horizontal).? Apparently it is.
I also saw that when the blade is twisted to be vertical the plane of its wide dimension passes through the M8 hole in the bracket seat.? That makes a lot of sense!? However, it doesn't seem to be exactly parallel to the long axis of the dovetail.? ?Maybe that's to account for the necessary clearance between the saw blade and guide bearings?? With zero clearance the blade and guide bearing axes would be parallel, but adding clearance would result in needing some additional "twist offset" on the part of the blade guide.? More clearance = more angular offset.? But how large is that angle?
Knowing that the bearings are 9mm long, for .005" clearance I calculate less than 1 degree. .010" would come to 1.6 degrees.? Not much to worry about I'd say.? So the dovetail alignment issue may be an observation error on my part (I just eyeballed it), or perhaps a minor design error.
Mark
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Hi John,
The 40 degree angle is closer to what I measured when I looked at the angle between the blade guide support's square dovetail and its body.? That's part #84 in my Harbor Freight owner's manual.? It's called the "lower blade guide bracket seat" in my manual.? But I wasn't sure if the plane of the bracket seat's body is anywhere close to vertical (when the body frame part #62 is horizontal).? Apparently it is.
I also saw that when the blade is twisted to be vertical the plane of its wide dimension passes through the M8 hole in the bracket seat.? That makes a lot of sense!? However, it doesn't seem to be exactly parallel to the long axis of the dovetail.? ?Maybe that's to account for the necessary clearance between the saw blade and guide bearings?? With zero clearance the blade and guide bearing axes would be parallel, but adding clearance would result in needing some additional "twist offset" on the part of the blade guide.? More clearance = more angular offset.? But how large is that angle?
Knowing that the bearings are 9mm long, for .005" clearance I calculate less than 1 degree. .010" would come to 1.6 degrees.? Not much to worry about I'd say.? So the dovetail alignment issue may be an observation error on my part (I just eyeballed it), or perhaps a minor design error.
Mark
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John Vreede
