FishingMan
Well-known member
I have a horizontal metal band saw that i want to build a hydraulic downfeed for. does anybody have any info on them or a source for a cylinder?
Hydraulic downfeed for bandsaw build?
- Thread starter FishingMan
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E.rodz
Well-known member
you can use a air cylinder with flow control valves on down side that is what most manufactures use now. also a screen door shock works with a needle valve to adjust to door closing as well.
StormcrowAz
Well-known member
matt_i
Well-known member
There's two parallel flow paths, that connect the two ports, the cylinder is oil filled.
One way is a quick exchange of fluid via a check valve that opens a large passage.
The other way is the needle valve which is the adjustable orifice.
If harbor freight has the assembly that's probably where I'd try first. Wellsaw, Dake/Kysor/Johnson also have parts but they're going to be more $$$.
There is also some form of spring balance usually. Its not totally sufficient to rely on the damper in most cases unless the saw is very neutrally balanced.
One way is a quick exchange of fluid via a check valve that opens a large passage.
The other way is the needle valve which is the adjustable orifice.
If harbor freight has the assembly that's probably where I'd try first. Wellsaw, Dake/Kysor/Johnson also have parts but they're going to be more $$$.
There is also some form of spring balance usually. Its not totally sufficient to rely on the damper in most cases unless the saw is very neutrally balanced.
csp
Well-known member
![IMG_3880[1].jpg](/forum/data/attachments/815/815664-59b05ec83d33662d1e1359932d279e57.jpg)
OP
FishingMan
Well-known member
Anyone have any part #s ? Thanks for the help guys
CSP & HotWire... How did you work around the cylinder area difference between the bore diameter and the rod diameter end? The volume of oil is different between the top of the cylinder and the bottom of the cylinder. When you stroke the cylinder to fully extend and back to fully retracted does the cylinder lock up before it can be fully retracted?
metlmunchr
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You fill the rod end of the cylinder to have the correct amount of oil. Because of this, if you raise the saw head part way and let it go, it will feel a bit "bouncy" due to the fact that there's still some air in the cylinder as opposed to the totally stiff feeling of a cylinder that's full of oil on both sides of the piston. This is normal, and a new saw will feel the same.
Honestly, a cylinder functions well as a shock absorber in the case where you lift the head part way and drop it. It keeps the head from slamming down and possibly damaging something. But a cylinder alone doesn't really provide much in the way of downfeed control when you're actually sawing something.
A saw really needs a counterbalance spring between the back end of the head and the base frame to control the effective weight of the head when the blade is in the cut. Most medium size industrial grade saws use a combination of the counterbalance spring to adjust head weight plus a cylinder as a shock absorber.
I've got 4 horizontal saws ranging from an old 4x6 Wilton that was made in Taiwan before US manufacturers discovered China, to a 1216 DoAll that'll cut 15" round stock. The little Wilton is really handy for cutting light gauge tubing and similar materials, but it required hand feeding the head down thru the stock as it had no counterbalance mechanism. I made a couple brackets and attached a spring with an adjustment screw to vary the head weight and that modification made it about 5X more useful as you can start the saw and let it feed itself thru the cut rather than standing there like a monkey and babying the blade down thru each cut.
BLUE72CAMARO
Well-known member
The other guys have you on the right path. Any pneumatic cylinder will work just fine as long as it has a mounting method that you can make pivot.
On my old Ridgid saw that I am selling the factory cylinder was majorly screwed when I bought it. Not sure how the previous owner managed to bend it but he did and in a big way. So i scrounged around in the dumpsters at work for quite some time and came up with the important parts of what you see here. Parker cylinder and flow control valve with a check in the other direction, I did add a ball valve to my system since I wanted to move the controls to a better location. It allows me to lock the travel in a position without adjusting my feed speed everytime.
The kalamazoo saw that I am just about done restoring has the same system but no ball valve but the controls for the flow control are all the way out by the clamping handle on them so its very easy to stop and open the controls. This saw is also much better balanced and doesnt require messing with the cylinder to control down pressure.
On my old Ridgid saw that I am selling the factory cylinder was majorly screwed when I bought it. Not sure how the previous owner managed to bend it but he did and in a big way. So i scrounged around in the dumpsters at work for quite some time and came up with the important parts of what you see here. Parker cylinder and flow control valve with a check in the other direction, I did add a ball valve to my system since I wanted to move the controls to a better location. It allows me to lock the travel in a position without adjusting my feed speed everytime.
The kalamazoo saw that I am just about done restoring has the same system but no ball valve but the controls for the flow control are all the way out by the clamping handle on them so its very easy to stop and open the controls. This saw is also much better balanced and doesnt require messing with the cylinder to control down pressure.
csp
Well-known member
Mine is neither fully extended nor fully retracted throughout the complete travel of the saw. The cylinder allows about 7" of stroke, but I only need 3" of that stroke between the locked into vertical position and the bottom of the horizontal position.
dkmc
Well-known member
Hey, that saw looks sharp. I have the same one, did a spruce up when I got it back in about 1985...If you haven't you should post a thread here on the work you've done to it.
The kalamazoo saw that I am just about done restoring has the same system but no ball valve but the controls for the flow control are all the way out by the clamping handle on them so its very easy to stop and open the controls. This saw is also much better balanced and doesnt require messing with the cylinder to control down pressure.
BD1
Well-known member
You could contact ELLIS for theirs. Here's what it looks like.
https://www.irvansmith.com/scart/el...UxDenve7GAsmN9uPP4AnRNYkKOH2Vb-saAoLqEALw_wcB
https://www.irvansmith.com/scart/el...UxDenve7GAsmN9uPP4AnRNYkKOH2Vb-saAoLqEALw_wcB
BLUE72CAMARO
Well-known member
Thanks!
I wish I had took better pictures along the way so I could but I didnt document things well at all. It was an operating basket case when I bought it. Luckily I only gave $90 for it so the $600 in parts it took to get it back right was a little easier to swallow. I am hoping to get the coolant tank painted this week and get it back on so I can call that project done and get back to the things I had planned to work on this winter.
metlmunchr
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- Sep 10, 2011
- Messages
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Can't tell from the pic whether your Kalamazoo is a model 7 or a 9, but both are similar in construction.
I've got a full automatic model 9, and when I got it I had trouble with it breaking blades for no apparent reason. Eventually figured out someone had "adjusted" the orientation of the idler wheel such that it was out of plane with the drive wheel. This put unequal tension across the blade and caused the breakage.
In realigning the idler I also found the misadjustment had caused the back of the blade to ride heavily against the flange of the wheel, wearing a good portion of the flange away. Turned a ring with a shrink fit to the wheel diameter and parted it off at the correct width to restore the flange, and then shrunk it in place on the wheel.
To get to the point, having the idler in the same plane and aligned with the drive is very important. To check this you can use a straight edge across the outer face of both wheels. A piece of 1/4 x 2 CR flat stock was plenty straight enough for this, standing on edge. Obviously the blade can't be tensioned while making adjustments to the idler, but it does need to be tensioned when checking with the straight edge as the frame will deflect somewhat when the blade is tightened. Took me a couple hours of messing with the adjustment and checking alignment, but it stopped the blade breakage and also stopped the blade from eating the wheel flange.
IMO, Kalamazoo kinda went overboard with the adjustability of the idler, and that makes it a PITA to adjust. I've also got a Wellsaw 850 which is about the same size saw, and it has a simple adjustment for tracking on the idler which works fine and doesn't have the multiple degrees of freedom that the Kalamazoo has.
I've got a full automatic model 9, and when I got it I had trouble with it breaking blades for no apparent reason. Eventually figured out someone had "adjusted" the orientation of the idler wheel such that it was out of plane with the drive wheel. This put unequal tension across the blade and caused the breakage.
In realigning the idler I also found the misadjustment had caused the back of the blade to ride heavily against the flange of the wheel, wearing a good portion of the flange away. Turned a ring with a shrink fit to the wheel diameter and parted it off at the correct width to restore the flange, and then shrunk it in place on the wheel.
To get to the point, having the idler in the same plane and aligned with the drive is very important. To check this you can use a straight edge across the outer face of both wheels. A piece of 1/4 x 2 CR flat stock was plenty straight enough for this, standing on edge. Obviously the blade can't be tensioned while making adjustments to the idler, but it does need to be tensioned when checking with the straight edge as the frame will deflect somewhat when the blade is tightened. Took me a couple hours of messing with the adjustment and checking alignment, but it stopped the blade breakage and also stopped the blade from eating the wheel flange.
IMO, Kalamazoo kinda went overboard with the adjustability of the idler, and that makes it a PITA to adjust. I've also got a Wellsaw 850 which is about the same size saw, and it has a simple adjustment for tracking on the idler which works fine and doesn't have the multiple degrees of freedom that the Kalamazoo has.
BLUE72CAMARO
Well-known member
It is a H9AW.
I ended up having to replace both wheels on it and had it as far apart as the saw can go without a grinder or torch lol. The drive wheel had become loose on the output shaft and worked the woodruff key to a 45 deg. or more angle screwing up the wheel bore and shaft. The idler had the same issue yours had with virtually no flange left but my lathe isnt big enough to spin the wheels for me to be able to repair what I had so I bought new wheels and a output shaft for the gearbox. Suprisingly the cheapest place for parts for the majority of what I ordered was thru clausing which now owns kalamazoo.
I agree on the idler being a pain in the a$$. I set mine using a straight edge to get them close and then put a blade on and ran it and made small adjustments to get the blade to ride just off the flange by a 1/32 or so on both wheels. So far it has worked great. I have probably made 40 or more cuts with it now making a custom horse stall door for a buddy of mine and not a single hiccup yet.
I ended up having to replace both wheels on it and had it as far apart as the saw can go without a grinder or torch lol. The drive wheel had become loose on the output shaft and worked the woodruff key to a 45 deg. or more angle screwing up the wheel bore and shaft. The idler had the same issue yours had with virtually no flange left but my lathe isnt big enough to spin the wheels for me to be able to repair what I had so I bought new wheels and a output shaft for the gearbox. Suprisingly the cheapest place for parts for the majority of what I ordered was thru clausing which now owns kalamazoo.
I agree on the idler being a pain in the a$$. I set mine using a straight edge to get them close and then put a blade on and ran it and made small adjustments to get the blade to ride just off the flange by a 1/32 or so on both wheels. So far it has worked great. I have probably made 40 or more cuts with it now making a custom horse stall door for a buddy of mine and not a single hiccup yet.
dkmc
Well-known member
My H9AW had multiple cracks around the cast iron wheels and a few on the iron frame as well. They were not noticeable before sand blasting. All got welded up with nickle rod and have held up well all these years. The wheel flanges are in good condition, but some monkey managed to saw off the corner of the angling jaw on the vise. I've also modified mine to accept a 1" blade that seems to work well.
BLUE72CAMARO
Well-known member
I stripped my saw down to bare metal everywhere and not a single crack was found. I did fill a cut thru the upper frame where the blade had walked off the drive wheel and cut thru the upper housing for about 60 deg. of rotation. Odd that yours was setup for 3/4" blade, mine is made to run 1" blades.
Gives you an idea of how far apart I had mine. LOL You can see the cut that I am talking about in the second picture
Gives you an idea of how far apart I had mine. LOL You can see the cut that I am talking about in the second picture
dkmc
Well-known member
I think the reason mine was a 3/4" blade is because it is actually a Model 8C-W not a H9AW. It's been 30? years since I last looked at the data plate. And, mine also has the groove in the frame like yours. Seems to be a common injury with Band Saws. Metal Band Saws seem to get their share of abuse out in the wild.
BLUE72CAMARO
Well-known member
Yeah i would say they are probably the most abused/neglected piece of equipment in most machine shops. I was showing a guy I do business with at work a couple pictures when I first started painting mine and his comment was so when do you plan to knock it over with a fork truck because thats the only time anyone pays any attention to ours at the shop.
dkmc
Well-known member
This guy did some very nice mods to the vise and table on his saw.
BLUE72CAMARO
Well-known member
I like his vise jaws for sure and the length gauge. I wish he had went into more detail about how it attached and showed what was under the saw that it mated with. I dont see the need for the post on the other side of the blade he had especially since it would have to be removed for any angle cutting.
dkmc
Well-known member
Yes, I'd like more detail too. I'd copy some of those features and they'd make the saw more fun to use and more efficient.
csp
Well-known member
![IMG_3884[1].jpg](/forum/data/attachments/870/870772-180862a5e9d43e8544d173b8b01c089c.jpg)
Keyblazer
Well-known member
Saw this the other day.
https://rover.ebay.com/rover/0/0/0?mpre=https://www.ebay.com/ulk/itm/193008081441
https://rover.ebay.com/rover/0/0/0?mpre=https://www.ebay.com/ulk/itm/193008081441
OP
FishingMan
Well-known member
The one on ebay is the one im wanting to build. Give me a reason to use my mill, lathe or welder. I need to know what parts to buy.