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| Author: | Goodin [ Mon Dec 27, 2010 11:06 pm ] |
| Post subject: | Jointer Issues |
Sorry for the long post. This is my first experience buying and setting up a jointer. I just spent a few hours with it so all this is fresh on my mind... So I am getting my shop set up and collecting power tools and last weekend I bought an old Powermatic 50, 6" jointer off of CL for real cheap. I did my homework before I checked it out. Put the straight edge (just a good Woodcraft ruler) on it, ran some feeler gauges and it seemed to check out ok, so I brought it home. The jointer is from about the 1950's and was in a Vo-tec school most of it's life so it has seen alot of use. Me and two buddies unloaded it out of the truck and I threw my back out and had to take off of work for a few days, another story;). When I got better I decided to try it out without checking the set up. After about three passes of a bookmatched set of dulcimer wood, i opened the bookmatched and it was way convex, like about a quarter inch at the ends. So I did more research, got a true, milled straight edge (the kind that stands up), and a One-Way Multi Gauge. Now I realize this thing is way out of whack. I am hoping some of you knowledgeable folks can help me out and shed some light on if this jointer is worth saving or making it into a boat anchor. With the Multi-gauge zeroed right at the edge near the blade on the outfeed table, i worked the gauge back to the end of the outfeed table. When I got about an inch back (from the outfeed table edge near the blade) the gauge went up .002" and as I checked various spots working back on the outfeed table it was about .001-.025" higher (than the edge near the blades). I did this same test on the infeed table and got about the same results. Will this be acceptable variances? The next step, I checked for coplaner. I set the Multi Gauge to zero at the edge near the blades and nearest to me, on the outfeed table, and brought up the infeed table to zero, then with the gauge on the infeed table near the knife edge, i moved the multi gauge towards the back and the gauge dropped .010". So this thing is way out of whack. I discovered the adjustment screws (two on each table), but im not sure how to use them properly, and the lower adjustment screw on the infeed table is twisted off. Also, all the knives were set .005" below the outfeed table. Had I been this knowledgeable and had straight edge and Multi Gauge while checking it out i probably would have passed on this jointer. With all this in mind, is it worth fooling with this machine? Would it be worth it to get the tables machined? Do they need it? Thanks for any advice. |
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| Author: | Mark Fogleman [ Mon Dec 27, 2010 11:43 pm ] |
| Post subject: | Re: Jointer Issues |
Marc Spagnolo (The Wood Whisperer) does an excellent job of explaining how to set up a jointer in this video starting at ~the 5 minute mark. Some older jointers need shims to get it coplaner. http://www.blip.tv/file/3585141?utm_source=player_embedded |
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| Author: | Michael Smith [ Tue Dec 28, 2010 4:26 am ] |
| Post subject: | Re: Jointer Issues |
If as you say you got it cheap I wouldn't kick myself. That is a very nice tool and it sounds like you just may not have it set up right. I don't use my jointer much for instrument making. I find a hand plane works better joining tops and backs. |
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| Author: | bluescreek [ Tue Dec 28, 2010 6:43 am ] |
| Post subject: | Re: Jointer Issues |
sounds like it needs a good setup . If you made sure there are no looseness in ths shaft . If you have 2 framing squares set them up with one on each table in feed and out feed and see that that squares mate . Once you get things set up and square you should be good. |
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| Author: | GregG [ Tue Dec 28, 2010 7:40 am ] |
| Post subject: | Re: Jointer Issues |
I'm not following you exactly with your explanation, But, that should be a very good machine and I would be surprised if it cannot be set up properly, though who knows maybe things are just too out of whack. You need to figure out how to adjust the tables, then follow the explanation someone else attached, it is a bit tricky to get one of these set up but once you do they will work great......In short, get the tables coplaner, then drop the infeed table a touch and run a level from the outfeed table over the blade, turn the blade by hand(machine unplugged)until the blade just touches the bottom of the ruler, no lifting of the ruler, I mean the blade just grazes the bottom of the ruler, reset your infeed table to proper height and give it a try. |
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| Author: | bluescreek [ Tue Dec 28, 2010 10:51 am ] |
| Post subject: | Re: Jointer Issues |
As a machinist we had to do this kind of work often . This should help getting you close on the out feed to blade adjustment . Take a piece of glass the thicker the better . Put a few drops of oil on the out feed table and lay the glass into that . The oil will cause a suction and hold the glass in plane . You can watch the oil move as the glass is contacted . this lets you know that the blades are planing above that table . It don't take much and this is more accurate that eyeballing . If you can get a magnetic base with a dial indicator you can adjust them perfectly . This tool is only as good as the set up . If not set up , it is just another pretty boat anchor that makes wood chips . I also found that the longer the time needed to set up a planer , the faster you will find a hidden nail in the next board . |
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| Author: | klooker [ Tue Dec 28, 2010 12:47 pm ] |
| Post subject: | Re: Jointer Issues |
Assuming the machine wasn't damaged in some way, you should be able to get it set up properly. IMHO the old US built Powermatic machinery is some of the best. You may want to try owwm.org for more help. Kevin Looker |
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| Author: | Goodin [ Tue Dec 28, 2010 2:22 pm ] |
| Post subject: | Re: Jointer Issues |
Hey guys - thanks for the great advice. I got a One-Way Multi Gauge ( http://www.oneway.ca/workshop/multi-gauge.htm ), so I won't have any problems setting up the knifes and getting the tables flat and co-planer. Hey Todd, I will check out John White's video. I am still a bit unsure how to "shim the ways". Can you explain a bit more how to do that? What are "ways"? I guess it's specific to each jointer. maybe i can take some pics of my jointer and post up here. im just not sure which bolts/screws to mess with. From the Woodwhisperer video, it appears that .002 inches is an acceptable tolerance. but to get a good edge joint for glue up, it needs to be perfect...so am i right to assume using a jointer for edging plates is out of the question? (I am working on a shooting board and getting a good plane, as that seems to be the preferred method here). |
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| Author: | Mark Fogleman [ Tue Dec 28, 2010 5:24 pm ] |
| Post subject: | Re: Jointer Issues |
I would put the Oneway gauge away until you get the beds coplaner. I don't think it can give you much useful information until you get to the blades. You need some MDF, a handful of drywall screws and 2 sets of feeler gauges. John White covers making Master, A, B bars and shimming in his book here: http://books.google.com/books?id=dSLOYOyQAmQC&pg=PA27&lpg=PA27&dq=john+white,+master+bar&source=bl&ots=NboURTbWOX&sig=Bvz_k0pkJ8ivn6p_pJ6IokOjTMM&hl=en&ei=I18aTfbXFML48AbRyt3nDQ&sa=X&oi=book_result&ct=result&resnum=1&ved=0CBcQ6AEwAA#v=onepage&q&f=false Use the second feeler gauge set as your shims. When you get the beds where they need to be then get your Oneway gauge and adjust your knives and the outfeed height. |
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| Author: | klooker [ Tue Dec 28, 2010 8:53 pm ] |
| Post subject: | Re: Jointer Issues |
Here's a manual. http://www.owwm.com/pubs/detail.aspx?id=1161 Ways are the inclined surfaces that the infeed & outfeed tables ride on - look at the manual & you'll see. Kevin Looker |
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| Author: | TomDl [ Wed Dec 29, 2010 5:20 am ] |
| Post subject: | Re: Jointer Issues |
You mention the blades are below the outfeed, that alone will make it cut convex. The way to test for correct set without a lot of fancy junk is to take a straight wood edge, and lay it on the outfeed over the blades. Rotate the blade in the cutting direction and the pieces of wood should lift and move approx 3/4" before the blade releases it. You will have to find the perfect length yourself, but that will get you started. Jointers do not make the edge straight without skill on the operators part. Most people seem to end up making convex edges at first. First if a pieces is not straight to start with running it over a jointer won't solve the problem automatically. You need to assess the edge and work the right part. If the part is convex, work in from the ends and take cuts until the machine can't cut any more because the ends are holding the center above the knives. When you get to that point, run the full length, but don't rock it through and round the edges again. Also be aware what your need to cut away. You don't want to cut a straight edge then find it isn't aligned with the grain as you want it to be. The basic process is assess the wood you want to get rid of and go after it. If you need tapered table legs you drop the wood in so the part in the apron is uncut and you will develop a taper,etc... Once the part is roughed out, go to the hollowing finishing pass routine to get the edge actually straight. Same thing with a hand plane. Make sure it is sharp, and beware a square head. |
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| Author: | TomDl [ Wed Dec 29, 2010 5:20 am ] |
| Post subject: | Re: Jointer Issues |
You mention the blades are below the outfeed, that alone will make it cut convex. The way to test for correct set without a lot of fancy junk is to take a straight wood edge, and lay it on the outfeed over the blades. Rotate the blade in the cutting direction and the pieces of wood should lift and move approx 3/4" before the blade releases it. You will have to find the perfect length yourself, but that will get you started. Jointers do not make the edge straight without skill on the operators part. Most people seem to end up making convex edges at first. First if a pieces is not straight to start with running it over a jointer won't solve the problem automatically. You need to assess the edge and work the right part. If the part is convex, work in from the ends and take cuts until the machine can't cut any more because the ends are holding the center above the knives. When you get to that point, run the full length, but don't rock it through and round the edges again. Also be aware what your need to cut away. You don't want to cut a straight edge then find it isn't aligned with the grain as you want it to be. The basic process is assess the wood you want to get rid of and go after it. If you need tapered table legs you drop the wood in so the part in the apron is uncut and you will develop a taper,etc... Once the part is roughed out, go to the hollowing finishing pass routine to get the edge actually straight. Same thing with a hand plane. Make sure it is sharp, and beware a square head. |
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| Author: | Goodin [ Wed Dec 29, 2010 9:02 am ] |
| Post subject: | Re: Jointer Issues |
Thanks guys, I went ahead and ordered the White book. It appears he is tuning a Powermatic 50 in his book. I don't think I will need to use the Master MDF method since I have a machined straight edge ($200???I got my 38" for 50 bucks) and the One-way multi gauge. Geez, I realized I have as much $$ in the set up tools as I do in the machine itself! I figured out what the gib scews are, i think, and the lower gib screw on the infeed table is twisted off. Looks like I will have to get it out of there some how, drill it out, or tap it. Is it possible to get replacement gib screws?? Tarhead said - "I would put the Oneway gauge away until you get the beds coplaner. I don't think it can give you much useful information until you get to the blades." Actually, I discovered that you can use it to check for flatness/twist of each table very accurately. Just zero the gauge at any point on the table (i started at the knife edge) and move the gauge at various points on the same table and it will tell you exactly the variances. It is also useful to zero the infeed table with the outfeed table. It's a great tool, glad i bought it. |
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