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Re: Mysterious shift in saw alignment
On Mon, Mar 21, 2022 at 12:17 PM, Mark Kimball wrote:
I actually removed the blade cover to see if that improved things, and it did -- but only a little. Totally familiar... Watch these videos I made about my saw! https://www.youtube.com/watch?v=SzjqDqpWRCA&list=PLz2A001hMBoQjJrC268cd6IzjxXQYZJEk? |
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Re: Mysterious shift in saw alignment
On Mon, Mar 21, 2022 at 03:35 PM, John Vreede wrote:
Mark2's sawframe hit that switch guard too. Maybe your saw is closer to the condition of his than you think? Mark Kimball, You saw looks just like mine. I've posted a bunch of picture just as a reference but to also show you the elevation plate. Note where I ground the clearance for the switch. This was done before I installed the plate. As John noticed it does look like your saw needs to be pushed to the left just going by the position of the blade in the slot in the lower casting. Mine was not like this but there was no way I could get mine to complete the cut without deflecting the blade downward.? ? Contact me if you want the plate in the picture. Mark? |
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Re: Mysterious shift in saw alignment
On Mon, Mar 21, 2022 at 03:35 PM, John Vreede wrote:
Mark2's sawframe hit that switch guard too. Maybe your saw is closer to the condition of his than you think? John, I agree 100%. This saw looks just like mine. Mine cut fine when I got is but the blade guides were deflecting the blade significantly downward. From what I am seeing it looks like the head needs to be pushed to the left and the pivot point lowered (which of course is hard to do). Also I thought the same about the pivot pin spacer but mine is the same as Mark1's (see attached). Mark1, I have an elevating plate I'll sell at a discount. It has extra holes in it but will function perfect.? ? Mark (2) ? ? ? |
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Re: Mysterious shift in saw alignment
That's a very weird?alignment.?? Sorry for more questions?but in the planview shot of the blade and slot, is the fixed jaw parallel and the blade square to the pivot axis? (because it's slanting across the the slot, indicative?of poor pivot bearing?hole drilling) Its way off centre of the slot too (cf with mine in 2nd pic). Also I've never seen a shouldered pivot shaft before - all my description of a spacer between the sawframe and the base pivot ears is nonsense on your machine. 'Normal' saws have a straight 15mm shaft through pivot arm casting base pivot ears and sawframe with a tubular spacer that fits over the pivot shaft between the sawframe and base pivot ear on RHS (see pic - much simpler I wonder why they changed this?). Your blade is so far over the RHS of the slot that there's no room to move the sawframe sideways anyway.? There is no way I'd have thought the sawframe would hit the base in that position. See the blade position in pretty much all my saws?in 2nd pic, where I believe it is designed to be. I think this off-centre alignment on your saw is the key to understanding why the sawframe doesn't clear the switch properly.? Mark2's sawframe hit that switch guard too. Maybe your saw is closer to the condition of his than you think? Earlier saws never had that guard, with ears on both sides, around the switch. Perhaps if you remove that it would clear some space? (I found the similar sheet-metal guard on my new saw?annoying and removed it, as you can't access the switch easily when the sawframe is close to the base).? Is that black washer fixed to the side of the base pivot ear with a screw or is that the spring pin you talked about - jv? ? On Tue, Mar 22, 2022 at 7:27 AM Mark Kimball <markkimball51@...> wrote: As promised, some photos. |
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Re: Mysterious shift in saw alignment
As promised, some photos.
1:? Blade alignment with no shims on the support bracket: Alignment with .050" shim stack: As low as she goes (look particularly at the blade guide on the right -- it is above the cutout in the base): Blade cover photos -- cover contacting base, scratch marks on cover showing location of contact(s): Photo showing pivot end of saw: Photo showing how far the sawframe can be moved over when the support bracket bolts are loosened: I ultimately was able to achieve decent alignment without shims by inserting a bladed screwdriver between one of the support bracket screws and support bracket and levering the sawframe over with it.? However, the blade cover still contacts the base so the blade drops just barely enough to cut through stock. That said, the blade now DOES completely cut through stock, and the alignment can be brought to the point where the saw can cut straight.? So it's still a mystery but I can coerce the saw into behaving in a reasonable fashion. Mark |
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Re: Mysterious shift in saw alignment
Mark, can you take some photographs.?? From what I understand from your description, there is enough movement in the slip joint between the pivot arm casting (yr #121) and the sawframe that the blade is nearly hitting the RHS of the slot and still the sawframe is fouling the base to the extent it doesn't complete the cut?? Definitely weird.? (if there wasn't enough movement you can file more clearance into the slots in #121, something I've routinely done on the saws I've adjusted. Would seem to me its hanging up somewhere other than the switch, and it's real difficult to see between the sawframe and the base at the best of times. Try draping a sheet of plastic or a cloth over the base and then lowering the sawframe.? Pull the sheet to see where it hangs up. Maybe there's?more than one pinch point - jv On Mon, Mar 21, 2022 at 3:56 PM Mark Kimball <markkimball51@...> wrote: Loosening the M10 screws on the support bracket, part #121, and pushing the sawframe over as far as it could go -- to the point where the blade was close to hitting the outfeed support nearest the front of the saw -- still did not permit the sawframe to drop down much more.? Pretty strange. |
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Re: Mysterious shift in saw alignment
On Sun, Mar 20, 2022 at 04:37 PM, John Vreede wrote:
?If these conditions do not exist, the saw will NOT cut both horizontally?and vertically square through a workpiece at the same time.??This is confusing to think about but also correct. I think I need to do a new video which includes the importance of the back jaw.? |
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Re: Mysterious shift in saw alignment
Hi all Just re-reading this thread to see if there's something I've missed and it occurs to me that MarkK has missed and important point in msg 16008 when he said: ? ? "Rotating the fixed jaw so it's perpendicular to the blade is not all that big a deal, so maybe I'm overthinking this.? It won't take much adjustment to the vise, and, given the fact that adjusting it to get square cuts is a common approach, it appears it's in my bandsaw's near future as well." Implicit in my statements in msg 16001 about "the heart of a 4x6...." being in the conditions of parallelism and squareness relationships of the workpiece and saw blade to the pivot axis, are 3 things I didn't say but should have:?
Mark can't adjust the sawframe and vice fixed jaw as he proposed in the quote above without compromising the vertical squareness.??That's?where just moving the whole sawframe sideways by changing the spacer length will work because it maintains those parallelism and squareness conditions Sorry for any misunderstandings- jv? On Sat, Mar 19, 2022 at 5:17 PM Mark Kimball <markkimball51@...> wrote: I wasn't able to do everything I wanted to on my bandsaw today, but was able to do some preliminary stuff.? The first thing I wanted to do was to set the fixed jaw so it 's parallel to the pivot shaft, using Rick Sparber's method with a 1-2-3 block and some other bits.? The thing with these saws is that they have so much adjustment range that it is all too easy to end up on an extreme that interferes with some other adjustment...so I wanted to first establish some kind of baseline. |
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Re: Mysterious shift in saw alignment
Mark2's comments are spot on, it takes very little fore and aft movement at the slip joint to move the head of the sawframe sideways quite a bit.
Can you give some measurements:
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Re: Mysterious shift in saw alignment
On Sun, Mar 20, 2022 at 12:51 PM, Mark Kimball wrote:
The direction of adjustment also doesn't look like it is purely on the horizontal axis, either? I have to conclude that the adjustment done there is normally expected to be quite small, certainly not enough to address my problem.Yes I agree, the amount of adjustment at this point would be limited by the clearance of the pivot point. However, it would not take much movement in this area to make a significant change at the switch end of the saw. I'd say the movement at the switch end would be about 4 times what you move at the back of the saw. Also, if the jack bolts are installed as indicated in the picture that John posted the adjustment would be purely horizontal (looking down on the saw it would move the switch end of the head left or right. I have no idea what might have moved but if you are seeing a horizontal change near the switch I'm thinking this back adjustment is the only place that will effect this.? |
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Re: Saw versions
I don't think it is any particular brand or model of saw.? These problems occur on all brands, from out of adjustment and not knowing what 'properly adjusted'?is, all the way up? to mis-manufacture?at the factory, and combinations of that in between. They've made 100's of 1000's of them over the years (1st one I know of that's recognisably a 4x6 was from Dayton in September1965), so the scope for not cutting well is huge.?? Given all the ways that things can go wrong I'd guess that <30% are made to their original drawing dimensions, and less than that are actually adjusted correctly (to give squareness better than 0.3% (0.003" per inch of cut or 0.03mm/cm of cut)).?? On Sun, Mar 20, 2022 at 1:20 PM mike allen <animal@...> wrote: ???? ??? I had one of the HF saws that I bought @ 25 years back I gave |
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Re: Mysterious shift in saw alignment
Still not sure why your saw suddenly won't cut all the way through - did you disassemble it at some point? The left-right position of the saw frame is set primarily by the spacer on the pivot shaft between the saw frame and base casting on the RHS of the saw so that, in?plan view, the blade runs in the centre of the gap between infeed and outfeed tables and parallel to the length of the gap. The length of this spacer varies according to manufacturer.? My old UC115 has a 15mm (~5/8") long spacer? while the yr2000 RF is only 8mm (5/16"). On the last saw (that?had seriously?misaligned holes for the pivot shaft in the base ears), I had to remove the spacer altogether, to get it to work.? A tell-tale of mis-aligned?drilling as above, is that the?blade does not run parallel to the slot between the infeed and outfeed tables.? If? (looking vertically down) the blade runs at an angle to this slot when the sawframe is resting horizontally, then this may be the reason why your sawframe now hits the base near the switch, especially if in the past the slip joint between the pivot arm casting and the sawframe was set so the sawframe did miss the base casting near the switch and horizontal squareness was achieved by adjusting the fixed vice jaw square to the blade instead of the other (proper) way round.?? If the blade is parallel to the slot but to the left of centre, then the spacer is too short. Even?If it's?parallel and central, just make a longer spacer for your machine to shift the sawframe to the right, then pack out the resultant gap between the pivot arm casting and the sawframe at the LHS rear. The blade not central?in the slot is no big deal and upsets nothing. If the blade angles across the slot now you've set the vice jaw parallel to the pivot shaft and adjusted the LHS rear joint so it cuts horizontally?square, then likely the pivot shaft holes in your sawframe or base casting are not drilled correctly. and that's a big deal to fix.? You cannot set the vice jaw at an angle to the pivot to compensate because then?the vertical cut cannot be made to cut square and there is no way to compensate for that (its complicated but the blade moving in 3-dimensional space just doesn't move vertically straight down anymore).? If that's?the case, just set the fixed vice jaw parallel to the pivot shaft and change the spacer length until the sawframe clears the base and it cuts full depth and accept the blade angling across the slot is going to look funny, but at least will be capable of cutting square in both directions - jv On Sat, Mar 19, 2022 at 5:17 PM Mark Kimball <markkimball51@...> wrote: I wasn't able to do everything I wanted to on my bandsaw today, but was able to do some preliminary stuff.? The first thing I wanted to do was to set the fixed jaw so it 's parallel to the pivot shaft, using Rick Sparber's method with a 1-2-3 block and some other bits.? The thing with these saws is that they have so much adjustment range that it is all too easy to end up on an extreme that interferes with some other adjustment...so I wanted to first establish some kind of baseline. |
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Re: Base casting measurements?
Hi Terry Yes it will be, but maybe not as much as you might want.? However, whatever?shortcomings you may find can be easily fixed. There are 3 major drawbacks of the original flimsy?sheet steel bases:
So it's a very useful improvement over the original. If it still makes too much noise you can damp?the vibrating?panel?with a steel plate bolted to it, with a bit of softish rubber sandwiched between.? The tippy-ness and flimsy legs can easily be overcome with a 1"x1/4" min. steel brace spanning from front to back legs on each side (see pic) and putting wider wheels on. say an old pair from a lawn mower. That still leaves it a bit prone to tipping over backwards when the sawframe is vertical (the weight of the sawframe and motor hanging behind the wheels with this stand), but that can be overcome by letting the brace project say 3-4" behind the rear legs and attaching the wheels there.? I actually prefer to have a tray, but find the swarf build up really annoying. So I use a thin (say 20-22G) sheet metal shield slipped between the base casting and the sheetmetal legs that is bent a bit at the top to?project?upward under the base casting, so no swarf falls into the tray.? It wraps under the RHS of the OEM tray and is pop-riveted to it so stiffens?the tray a lot.?? Your new set of legs has the shield on the wrong side, blocking access to the LHS, of the saw, so has no possibility of a tray. But if you installed the legs under the base end for end, and positioned the wheels on the lengthened brace (so the shield is now on the RHS) you could install a plywood tray AND get additional cross bracing to make the new stand even more rigid and less noisy.? You'd have to pop-rivet a short extension to the top of the?shield to fill up under the base casting to deflect swarf from the?slot between the infeed and outfeed tables. Your new stand is way better than the original and much better than the open stands made from 16G angle section on newer Grizzly and RF saws.?Its not the manly, 400HP, Tim-the-Toolman style of a stand built in 2"x2"x1/4" tube that many prefer, but, that said, I've?never built a new stand from scratch, as my?2 saws with original flimsy sheet metal bases are more than rigid enough with the mods shown in the pics.? Your new base will be more than adequate in stock form and easily upgraded if you find it necessary - jv? On Sun, Mar 20, 2022 at 3:43 AM terry keeley <tkee@...> wrote: I have the stand coming, says it's made from 14 ga (0.075") steel sheet, is it much of an improvement over the previous paper thin versions? |
Mark
John Vreede
