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While I was waiting for new blades from sawblade.com to arrive this week, I spent some quality time with my saw and discovered that there was a lot of gunk between the blade guide bar and the slot it fits into (the one closer to the hinge end of the saw).? Cleaning it up actually straightened the blade out a bit, but only by a degree or two.? I tried inverting the blade too, but it didn't make any difference.? ?When the new blades showed up today, they still cut at an angle, so I knew it wasn't the blade.? I thought about shimming the blade guides to change the angle of the blade, but that wouldn't fix the problem, just the symptoms.? I adjusted the cams, and it cut a little straighter, but after about a minute of cutting some aluminum, the blade suddenly stopped.? One of the bearings had broken (a chunk fell out of the outer race!) and the dust caps had popped off.? Obviously way too tight.? Another set of bearings was swapped in, and then the blade wouldn't stay on the wheels.? This was going downhill fast, so I stepped back and realized that the best way to adjust the bearings was without the blade, and off the machine.? Much easier!? I only did one test cut, which was almost perfect, and left it to work on some other things.
Last week, when I checked the HF blade for squareness, it looked right on (both before and after I inverted it.).? Today when I checked the new blade, it was obviously not square, but both cut at the same angle before adjustment.? If further tweaking doesn't make it cut dead straight consistently, I'm thinking about adding set screws to channels the guide bars sit in so that the angle can be finely adjusted.
-Dave
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Dave, just trying to decipher what you've said. Have you got one of those old HF 'Greenie' saws with the one-piece cast alloy guide assemblies sliding on the outside of the sawframe casting, where the guide brackets carrying the rollers are not adjustable on the guide bars? If yes, then shimming the bar off the raised tracks on the sawframe casting is a good idea.? I have also seen people?put set screws into the casting to get some adjustment. Bit?puzzled by you?getting an 'almost?perfect' cut, if the angle of the blade-body is not square to the vice table. The only problem with setscrews?is that they provide a point loading on the guide bars and will dent the soft alloy and more likely, twist/bend the guide bars as you tighten, unless they're right next to the clamping handwheel.? I think a strip of shim will be better at transferring?the load.? You can get shim that is made up of?leaves of 0.001" that you peel away until you get the right thickness, like this from McMasterCarr?.? Just stick it to the casting with double sided tape. The aluminium stuff is cheapest though you can get it in brass, steel and stainless too.? If your guides are aluminium there's no point in anything more expensive - jv
On Sat, Apr 17, 2021 at 5:47 PM Dave Seiter < d.seiter@...> wrote:
While I was waiting for new blades from to arrive this week, I spent some quality time with my saw and discovered that there was a lot of gunk between the blade guide bar and the slot it fits into (the one closer to the hinge end of the saw).? Cleaning it up actually straightened the blade out a bit, but only by a degree or two.? I tried inverting the blade too, but it didn't make any difference.? ?When the new blades showed up today, they still cut at an angle, so I knew it wasn't the blade.? I thought about shimming the blade guides to change the angle of the blade, but that wouldn't fix the problem, just the symptoms.? I adjusted the cams, and it cut a little straighter, but after about a minute of cutting some aluminum, the blade suddenly stopped.? One of the bearings had broken (a chunk fell out of the outer race!) and the dust caps had popped off.? Obviously way too tight.? Another set of bearings was swapped in, and then the blade wouldn't stay on the wheels.? This was going downhill fast, so I stepped back and realized that the best way to adjust the bearings was without the blade, and off the machine.? Much easier!? I only did one test cut, which was almost perfect, and left it to work on some other things.
Last week, when I checked the HF blade for squareness, it looked right on (both before and after I inverted it.).? Today when I checked the new blade, it was obviously not square, but both cut at the same angle before adjustment.? If further tweaking doesn't make it cut dead straight consistently, I'm thinking about adding set screws to channels the guide bars sit in so that the angle can be finely adjusted.
-Dave
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Hi John-
My saw is an '85 Packard with a capacity greater than most 4x6s (there are photos of it in the photo section under Packard).? I may have something similar to what you mention:? the roller guide assemblies have a channel cut into them, so when bolted onto the guide bars, they are fixed and have no adjustment.? (It's all cast iron)? The only real adjustments my saw has are blade tension, down feed, horizontal guide location and the guide cams.?
I was tired when I wrote it last night, so confusion is very understandable.? I did get the blade square to the table, at least as well as can be seen in bad light with only 1/2" to compare.? While I like the idea of set screws for adjustment, you're right about potentially bending/ twisting the guide bars.? Three per side would work (with the middle one next to the hand wheel), but then adjustments would become tiresome.? The double sided tape is a great idea, as I have a many rolls of stainless shin stock.? Even aluminum duct tape would work.? I've never seen the peel-away stuff before; that's good to know about!
-Dave
On Saturday, April 17, 2021, 02:07:47 PM PDT, John Vreede <vreededesign@...> wrote:
Dave, just trying to decipher what you've said. Have you got one of those old HF 'Greenie' saws with the one-piece cast alloy guide assemblies sliding on the outside of the sawframe casting, where the guide brackets carrying the rollers are not adjustable on the guide bars? If yes, then shimming the bar off the raised tracks on the sawframe casting is a good idea.? I have also seen people?put set screws into the casting to get some adjustment. Bit?puzzled by you?getting an 'almost?perfect' cut, if the angle of the blade-body is not square to the vice table. The only problem with setscrews?is that they provide a point loading on the guide bars and will dent the soft alloy and more likely, twist/bend the guide bars as you tighten, unless they're right next to the clamping handwheel.? I think a strip of shim will be better at transferring?the load.? You can get shim that is made up of?leaves of 0.001" that you peel away until you get the right thickness, like this from McMasterCarr?.? Just stick it to the casting with double sided tape. The aluminium stuff is cheapest though you can get it in brass, steel and stainless too.? If your guides are aluminium there's no point in anything more expensive - jv
On Sat, Apr 17, 2021 at 5:47 PM Dave Seiter < d.seiter@...> wrote:
While I was waiting for new blades from to arrive this week, I spent some quality time with my saw and discovered that there was a lot of gunk between the blade guide bar and the slot it fits into (the one closer to the hinge end of the saw).? Cleaning it up actually straightened the blade out a bit, but only by a degree or two.? I tried inverting the blade too, but it didn't make any difference.? ?When the new blades showed up today, they still cut at an angle, so I knew it wasn't the blade.? I thought about shimming the blade guides to change the angle of the blade, but that wouldn't fix the problem, just the symptoms.? I adjusted the cams, and it cut a little straighter, but after about a minute of cutting some aluminum, the blade suddenly stopped.? One of the bearings had broken (a chunk fell out of the outer race!) and the dust caps had popped off.? Obviously way too tight.? Another set of bearings was swapped in, and then the blade wouldn't stay on the wheels.? This was going downhill fast, so I stepped back and realized that the best way to adjust the bearings was without the blade, and off the machine.? Much easier!? I only did one test cut, which was almost perfect, and left it to work on some other things.
Last week, when I checked the HF blade for squareness, it looked right on (both before and after I inverted it.).? Today when I checked the new blade, it was obviously not square, but both cut at the same angle before adjustment.? If further tweaking doesn't make it cut dead straight consistently, I'm thinking about adding set screws to channels the guide bars sit in so that the angle can be finely adjusted.
-Dave
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Unless I'm missing something Dave your saw is the same as most everyone else's, and I was talking about something else entirely? Let's define some terms first: The guide assembly is made up of a guide bar that slides in the sawframe casting.? A?guide bracket that holds all the rollers is bolted on top of the guide bar with a wide/shallow tongue&groove?joint. There is a 5/16' UNC bolt that fixes the two together. From the look of the photos you've posted, there may not be much, if any, rotation adjustment in your guide bracket-to-guide bar joint.
It is rotation of this joint around the axis of the fixing bolt that twists the blade square to the vice table.? If you have not enough rotational movement to get the blade square (quite a common problem), then working with a file on the edges of the tongue will give it to you. You don't?need to remove much, just a triangle of metal from the corners that are touching the guide bar groove which ever way it needs to rotate. Now I figure you were talking about set screws in the edge of the groove like the attached photo. The std groove is too shallow for even 1/8" set screws so you need to mill it deeper. These are 0.200". Don't put the screws too closer to the ends as the joint still has to slide fore&aft.? 1/4" bolt in back is to so you maintain the set blade back to rer roller clearance while adjusting blade twist.? You really need to have good way of seeing that blade is perfectly at right angles to the vice table surface like flat 6" rule clipped to the blade back - jv ??
On Sun, Apr 18, 2021 at 10:10 AM Dave Seiter < d.seiter@...> wrote:
Hi John-
My saw is an '85 Packard with a capacity greater than most 4x6s (there are photos of it in the photo section under Packard).? I may have something similar to what you mention:? the roller guide assemblies have a channel cut into them, so when bolted onto the guide bars, they are fixed and have no adjustment.? (It's all cast iron)? The only real adjustments my saw has are blade tension, down feed, horizontal guide location and the guide cams.?
I was tired when I wrote it last night, so confusion is very understandable.? I did get the blade square to the table, at least as well as can be seen in bad light with only 1/2" to compare.? While I like the idea of set screws for adjustment, you're right about potentially bending/ twisting the guide bars.? Three per side would work (with the middle one next to the hand wheel), but then adjustments would become tiresome.? The double sided tape is a great idea, as I have a many rolls of stainless shin stock.? Even aluminum duct tape would work.? I've never seen the peel-away stuff before; that's good to know about!
-Dave
On Saturday, April 17, 2021, 02:07:47 PM PDT, John Vreede < vreededesign@...> wrote:
Dave, just trying to decipher what you've said. Have you got one of those old HF 'Greenie' saws with the one-piece cast alloy guide assemblies sliding on the outside of the sawframe casting, where the guide brackets carrying the rollers are not adjustable on the guide bars? If yes, then shimming the bar off the raised tracks on the sawframe casting is a good idea.? I have also seen people?put set screws into the casting to get some adjustment. Bit?puzzled by you?getting an 'almost?perfect' cut, if the angle of the blade-body is not square to the vice table. The only problem with setscrews?is that they provide a point loading on the guide bars and will dent the soft alloy and more likely, twist/bend the guide bars as you tighten, unless they're right next to the clamping handwheel.? I think a strip of shim will be better at transferring?the load.? You can get shim that is made up of?leaves of 0.001" that you peel away until you get the right thickness, like this from McMasterCarr?.? Just stick it to the casting with double sided tape. The aluminium stuff is cheapest though you can get it in brass, steel and stainless too.? If your guides are aluminium there's no point in anything more expensive - jv On Sat, Apr 17, 2021 at 5:47 PM Dave Seiter < d.seiter@...> wrote:
While I was waiting for new blades from to arrive this week, I spent some quality time with my saw and discovered that there was a lot of gunk between the blade guide bar and the slot it fits into (the one closer to the hinge end of the saw).? Cleaning it up actually straightened the blade out a bit, but only by a degree or two.? I tried inverting the blade too, but it didn't make any difference.? ?When the new blades showed up today, they still cut at an angle, so I knew it wasn't the blade.? I thought about shimming the blade guides to change the angle of the blade, but that wouldn't fix the problem, just the symptoms.? I adjusted the cams, and it cut a little straighter, but after about a minute of cutting some aluminum, the blade suddenly stopped.? One of the bearings had broken (a chunk fell out of the outer race!) and the dust caps had popped off.? Obviously way too tight.? Another set of bearings was swapped in, and then the blade wouldn't stay on the wheels.? This was going downhill fast, so I stepped back and realized that the best way to adjust the bearings was without the blade, and off the machine.? Much easier!? I only did one test cut, which was almost perfect, and left it to work on some other things.
Last week, when I checked the HF blade for squareness, it looked right on (both before and after I inverted it.).? Today when I checked the new blade, it was obviously not square, but both cut at the same angle before adjustment.? If further tweaking doesn't make it cut dead straight consistently, I'm thinking about adding set screws to channels the guide bars sit in so that the angle can be finely adjusted.
-Dave
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John Vreede
