lewisc Posted February 22, 2017 Report Share Posted February 22, 2017 II'm struggling to get flat cuts on the jointer. Hopefully the pictures will explain what I might struggle with in words. I think my technique is fine - I'm keeping consistent pressure on the board as it passes over the blades. The board I was testing with seems to cut so the opposite corners on the diagonal are not flat. The video Marc does on Jointer setup has been really useful in understanding terms and what needs to happen to set this thing up properly. The things I think I can narrow it down to are: Technique In feed and out feed tables not coplanar (slowly learning about this one) Blades need adjusting. I'll be picking up a straight edge so I can start checking a few things and I've got a digital height gauge for the blades. Quote Link to comment Share on other sites More sharing options...
Keggers Posted February 23, 2017 Report Share Posted February 23, 2017 From your pictures it looks like your board has a twist in it. Apply pressure on the low sides of your board as you run it through. That would be the side touching the jointer table top. Keep in mind that most of your pressure should be on the out feed side of the blade with light pressure on the in feed side. As you get towards the end of the board switch pressure to the low portion on this end. I hope I explained this clear enough to be helpful if it's a technique issue. . Quote Link to comment Share on other sites More sharing options...
lewisc Posted February 23, 2017 Author Report Share Posted February 23, 2017 I never thought of the board. I'll try a few more pieces to see if I get consistent results. Update: I've tried a few more boards. A piece of Pine and another of Jarrah. Both have the same problem. When sitting on the jointer out feed table, the opposite diagonal corner is raised. I'm really hoping it's the machine and not my technique. Quote Link to comment Share on other sites More sharing options...
gee-dub Posted February 23, 2017 Report Share Posted February 23, 2017 Let's assume the machine is OK (maybe its not) . . . when you say " I think my technique is fine - I'm keeping consistent pressure on the board as it passes over the blades. ", where are you keeping constant pressure? Once 6" or so is past the cutterhead, the pressure on the infeed table is not much more than that required to move the board forward. Once that material has past the cutterhead it should reference your outfeed. The degree that it will solidly reference the outfeed depends on the amount of irregularity, The boards you show should seat well on the outfeed after one pass. I'm not saying they will be done in one pass but, with that minor of a deviation, the majority of the surface should be milled flat. If you continue to press down on a part of the board that is not already in contact with the tables, it will teeter-totter and foul the path. Unfortunately Gary Rogowski's video is no longer up but, I direct you to Marc's Vid. No offense to Marc but, he sort of rushes through the process without a lot of discussion about what and why. Let me dig a little . . . Alas, nothing that really floats my boat. Gary's video goes into detail about how to handle various boards with bow, twist cup, etc. Fundamentally I always run so that I cut with the grain, I place the cup down, I tail cut badly bowed boards. By tail cut I mean that if the board is bowed enough to have the ends straddle the cutterhead without touching it I will start in the middle and joint each end a bit before starting a more normal jointing process. 2 Quote Link to comment Share on other sites More sharing options...
lewisc Posted February 23, 2017 Author Report Share Posted February 23, 2017 2 hours ago, gee-dub said: Let's assume the machine is OK (maybe its not) . . . when you say " I think my technique is fine - I'm keeping consistent pressure on the board as it passes over the blades. ", where are you keeping constant pressure? Once 6" or so is past the cutterhead, the pressure on the infeed table is not much more than that required to move the board forward. Once that material has past the cutterhead it should reference your outfeed. The degree that it will solidly reference the outfeed depends on the amount of irregularity, The boards you show should seat well on the outfeed after one pass. I'm not saying they will be done in one pass but, with that minor of a deviation, the majority of the surface should be milled flat. If you continue to press down on a part of the board that is not already in contact with the tables, it will teeter-totter and foul the path. Unfortunately Gary Rogowski's video is no longer up but, I direct you to Marc's Vid. No offense to Marc but, he sort of rushes through the process without a lot of discussion about what and why. Let me dig a little . . . Alas, nothing that really floats my boat. Gary's video goes into detail about how to handle various boards with bow, twist cup, etc. Fundamentally I always run so that I cut with the grain, I place the cup down, I tail cut badly bowed boards. By tail cut I mean that if the board is bowed enough to have the ends straddle the cutterhead without touching it I will start in the middle and joint each end a bit before starting a more normal jointing process. I'll watch a few more videos on setup and technique. I've had great success with it in the past but recently, it hasn't been working as it should. I don't know if things might have rattled loose, or something was knocked when I recently change belts - I just know something needs to change either on the machine or my technique. I use a push stick at the back to feed and a flat push stick for the top of the timber. As I get just past the cutterhead, I keep pressure on that part of the timber as it feeds through. Maybe I'm not following through enough? I'll be getting a straight edge in the next few days so I can do some testing. Quote Link to comment Share on other sites More sharing options...
gee-dub Posted February 23, 2017 Report Share Posted February 23, 2017 Sounds like you are on track. I can confess to having certain methods morph a bit over time and I have to sort of reset my thinking to correct for it. The straight edge will help you eliminate the machine; it may be that you are fine and the machine has the issue. Quote Link to comment Share on other sites More sharing options...
Mick S Posted February 23, 2017 Report Share Posted February 23, 2017 I'm not sure if this video link is in the members only section, but it might help if you have access to it. Quote Link to comment Share on other sites More sharing options...
Eric. Posted February 23, 2017 Report Share Posted February 23, 2017 Sounds like a coplanarity issue to me, like one of the outer corners of the outfeed dips down or one of the knives is improperly set. When a jointer is perfectly tuned it's hard to not get a flat board unless you have some pretty egregious technique issues. Sent from my SCH-I545 using Tapatalk Quote Link to comment Share on other sites More sharing options...
wtnhighlander Posted February 24, 2017 Report Share Posted February 24, 2017 Sounds like a coplanarity issue to me, like one of the outer corners of the outfeed dips down or one of the knives is improperly set. When a jointer is perfectly tuned it's hard to not get a flat board unless you have some pretty egregious technique issues. Sent from my SCH-I545 using Tapatalk I don't know about the rest of you, but my vocabulary just expanded! Wait......@Eric. is using TapaTalk??? Quote Link to comment Share on other sites More sharing options...
gee-dub Posted February 24, 2017 Report Share Posted February 24, 2017 Thanks micks, that van dyke video is a good example of what I was looking for. Quote Link to comment Share on other sites More sharing options...
Ronn W Posted February 24, 2017 Report Share Posted February 24, 2017 If you have a board that is already flat run it through and see if it stays flat. That will tell you if the table need adjusting. When face planing I usually run the first pass with very little pressure so that I don't bend the board. I want the part that are naturally in contact with the table to be cut first. If the board is riding high on opposite corners I try to "balance" it on those corners for the first couple of passes. If your first cut can be as deep as the corner gap under the board, you may take the twist out in one(maybe 2) passes. Quote Link to comment Share on other sites More sharing options...
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