twisted jointer fence: have machined or buy new?

[michael langman]

Meehanite cast iron was used on all american made machine tools of good quality up until they were put out of business by the japanese and then china. The process of making meehanite cast iron is much more expensive and controlled then making other types of cast iron.
Unless it is specified if it does not say meehanite in the description of the machine then you can assume that the cast iron is inferior and a hit or miss on it's long term stability, and quality.
When machines were made here in the USA most companys had their own foundries and their castings were made at least a year or two in advance of being machined for finish purposes. It was also a good practice to rough machine a casting, let it sit for a while and then finish machine it later. This allowed the casting to stabilize also.
Castings were left outside in the elements in the north too as the temperature changes helped stabilize the casting.

Using a wood subfence on the warped fence is a good idea as the casting may not be worth machining if it was not designed with enough cross ribbing to help keep it straight and flat.
If you try to machine some bosses on the backside to help hold it during grinding it will cause movement issues,so good fixturing is needed .

[Mike Kees]

I have straightened a jointer fence by suspending it between two 4x4's and stepping on it slowly applying my weight. It worked like a charm. I think you could put it in a vise and slowly and evenly twist ,you will feel it "give". Stop at that point.

[David Kumm]

I'm in the subfence camp as I'm not sure they make straight fences for jointers. Dave

[Andrew Hughes]

My experience with jointer fences is they really don’t need to be perfectly flat to get good square edges.
A convex shape from end to end is what I prefer.
This way a small section of the fence can be set square to the outfeed just past the cutter. Pressure is applied at the this spot. Confidence and a sure hand is developed
A badly twisted fence is obviously a bummer. But really only a small section might need to be removed the end that tips a board against your plan.
Good Luck

[Mel Fulks]

I’ve never used a jointer fence that would hold 90 degrees, for glue ups I just do face in , face out... I have seen guys make a good
start on a barrel by not ....emulating me. Fence twist is not acceptable...’course ya gotta be proud that the manufacturer thinks YOU COULD fix it !

[johnny means]

My experience with jointer fences is they really don’t need to be perfectly flat to get good square edges.
A convex shape from end to end is what I prefer.
This way a small section of the fence can be set square to the outfeed just past the cutter. Pressure is applied at the this spot. Confidence and a sure hand is developed
A badly twisted fence is obviously a bummer. But really only a small section might need to be removed the end that tips a board against your plan.
Good Luck

I was thinking the same. Especially with longer boards that may have a little bow along the length.

[Bruce Lowekamp]

Thanks for all the great responses. Though I guess in some sense the answer is ultimately more depressing than I hoped, but at least I know I'm not alone.

For my particular problem, I've decided not to buy a replacement Grizzly fence; it seems like I'm not terribly likely to improve the situation. The wooden secondary fence is obviously the easiest, though I have to make peace with drilling holes in my fence (which feels wrong even though it's twisted). It occurs to me I need to get a countertop for the sink vanity I'm making, and maybe I could get a scrap of granite/quartz about the right dimensions and use that as a fence. Also a bunch of options like buying an aluminum fence from a JJP-10 (not sure I believe it's likely to be flatter, but would be easier to bend back) or various t-tracks.

decisions, decision...

Bruce

[Curt Harms]

Thanks for all the great responses. Though I guess in some sense the answer is ultimately more depressing than I hoped, but at least I know I'm not alone.

For my particular problem, I've decided not to buy a replacement Grizzly fence; it seems like I'm not terribly likely to improve the situation. The wooden secondary fence is obviously the easiest, though I have to make peace with drilling holes in my fence (which feels wrong even though it's twisted). It occurs to me I need to get a countertop for the sink vanity I'm making, and maybe I could get a scrap of granite/quartz about the right dimensions and use that as a fence. Also a bunch of options like buying an aluminum fence from a JJP-10 (not sure I believe it's likely to be flatter, but would be easier to bend back) or various t-tracks.

decisions, decision...

Bruce

You don't want the thickness of any 'subfence' to reduce the capacity of the jointer too much. I've drilled Asian cast iron a couple times, it was uneventful. My JJP-12 has an aluminum extrusion for a fence, I don't detect any distortion.

[Brian Holcombe]

I would not use granite for the fence.

I didn't think about the face plate earlier, but thats' not a bad idea. I think I would just use a sheet of UHMW thick enough to retain its form while you cut it.

[michael langman]

Try using double back tape to put the wood fence on the warped one.

[Paul Haus]

I picked up some plastic sheet material a number of years back. Not sure what it is made of but it's around 1/2" thick by 8" wide and about 4' in length. It's dead flat and even the full length. I used it on an old jointer with a twisted fence. Drilled it to match the fence and shimmed it till it was uniform along the entire length of the machine. Used it that way for a numbe of years and it worked fine for me. I even added it to my 8" Delta when I got that one to have a taller fence and it's worked fine there too.