Need LA machine shop to grind jointer fence flat!

[Jason White]

I have an old Delta DJ20 jointer and the cast-iron fence is warped. Anybody know a good machine shop in the San Fernando Valley that could grind it flat for me?

Thanks for any suggestions!

- Jason

[Andrew Hughes]

Hi Jason, I looked into that once out here in Pomona area we lots of machine shops,they told me it would be expensive not a straight forward thing to do.What I do with may crooked fence is square the fence to the table just past the cutter head.
and press there when edge jointing.
I too am setting up a used jointer, hopefully it will work as well as my old 8 inch.Andrew

[Sean Solan]

Hey Jason. I just joined SMC, it's nice to meet you. I'm in the SF Valley as well. I'm going to keep an eye on this thread because I've often been looking for a quality machine shop. As you know they're tough to find around LA. Not to jump your thread but do you know a good welding / metal fabricator in the Valley? I'm building a router extension wing for my SawStop. Thanks & good luck.

[Jason White]

Hi, Sean. Sorry -- I don't have any personal experience with metal fabricators here.

- Jason


Hey Jason. I just joined SMC, it's nice to meet you. I'm in the SF Valley as well. I'm going to keep an eye on this thread because I've often been looking for a quality machine shop. As you know they're tough to find around LA. Not to jump your thread but do you know a good welding / metal fabricator in the Valley? I'm building a router extension wing for my SawStop. Thanks & good luck.

[Jason White]

Andrew -- Mine is much worse than that, unfortunately. It's got a high spot/crown right in the middle where wood passes over the cutter head.

I've thought about setting it on a flat surface and pounding on it to try and make it flat, but I fear that might crack it.

- Jason

[Jeff Duncan]

Don't pound on it!!! That's a sure fire disaster waiting to happen! Cast iron is brittle and does not take well to shock:eek:

There was an article in Fine Woodworking maybe 30 years or so ago on taking the bend out of Powermatic jointer fences that had gone out. IIRC the general principle was to lay the fence down like a bridge over 2 support blocks on either end. You then start adding downward force slowly and steadily until you feel it "pop" back into position. Once it pops it should be in it's original position and you don't want to stress it any farther. I don't know if they have old articles available online or anything but may be worth a little searching.

Now this is just what I remember from memory, I haven't tried it and so can't vouch for it, plus it was specifically in relation to PM fences which supposedly had the "magic" cast iron process of the time so a lot of variables there. Just something you may want to look into further before acting on any plan;)

good luck,
JeffD

[Mark Bolton]

Assuming you searched the internet's, and no idea of the proximity but just punching in "blanchard grinding san fernando valley ca" came up with a bunch, an sherman oaks listed the same. I would guess one of those shops could give you some direction on a shop which could surface it for you?

http://www.yellowpages.com/pacoima-ca/blanchard-grinding

http://www.yellowpages.com/pacoima-ca/blanchard-grinding

[Mark Carlson]

Could you attach/shim a wooden auxiliary fence to the warped one?

~mark

[Chris Fournier]

If the fence is 90 degrees to the work surface from start to finish you're laughing, "straight" don't matter.

[Sam Puhalovich]

Take it to a engine re-builder. The 'head-surfacer' will handle that in a cinch.
I had both tables of my 12" jointer re-surfaced by one.
Set-up took about 10 minutes ... machine cut about 20 minutes ... $50 each.

[Jason White]

UPDATE: I got a bid of $150 to Blanchard grind the fence, so last night I propped the fence on a couple of softwood blocks and smacked the middle of the fence a few times with my large deadblow mallet. Now its dead nuts straight. Hoping it stays that way! If not, I'll have to cough up the dough to grind it.

[Brian Brightwell]

I was in the need for truing the throat plate on my Laguna table saw. This is a large throat plate, about 4 times the size of a Power Matic. I finally attached the plate to a board and used my wide belt sander. I took very light passes and it took awhile but it was flat when done.

[Mark Bolton]

UPDATE: I got a bid of $150 to Blanchard grind the fence, so last night I propped the fence on a couple of softwood blocks and smacked the middle of the fence a few times with my large deadblow mallet. Now its dead nuts straight. Hoping it stays that way! If not, I'll have to cough up the dough to grind it.

Scary for sure. As Jeff mentioned its a major roll of the dice. Cast iron does not play well when bent. What usually happens is you push it "just" to the point where it needs to be and "pop" it cracks. $150 sounds like a steal deal to me. If it doesnt stay straight I would never hit it again :rolleyes:, the replacement would likely put 150 to shame.

[Jason White]

Yeah, I figured I'd roll the dice on this one. A replacement fence is $300-400.

The old one is thick and has a lot of webbing for reinforcement on the backside, and I took my time with it. Had it been flimsy looking and more badly warped, I wouldn't have tried this approach.

That said, so far so good! :D

JW



Scary for sure. As Jeff mentioned its a major roll of the dice. Cast iron does not play well when bent. What usually happens is you push it "just" to the point where it needs to be and "pop" it cracks. $150 sounds like a steal deal to me. If it doesnt stay straight I would never hit it again :rolleyes:, the replacement would likely put 150 to shame.

[Mark Bolton]

Yeah, I figured I'd roll the dice on this one. A replacement fence is $300-400.

The old one is thick and has a lot of webbing for reinforcement on the backside, and I took my time with it. Had it been flimsy looking and more badly warped, I wouldn't have tried this approach.

That said, so far so good! :D

JW

Glad it worked out for you. Just remember thick or thin, webbing or not, cast iron is no different than porcelain (a dinner plate), an aluminum wheel on your car (alloy), glass.

As a rule it has zero tolerance for bending. At least the replacement isnt as bad as it could be. It'll be great if it stays in shape for you.

Ive heard of people having success bending thin cast iron pieces with a lot of heat but then you risk introducing stress and more problems.

Just ride the wave! :)

[Rick Lizek]

Comparing porcelain isn't even close to glass. When I bought a 6" Powermatic Jointer 40 years ago there was a warp to the fence. I was talking to the Regional Sales Manager to fix the problem and the first thing he said was to put it on a couple of blocks and use a clamp to put gradual pressure to straighten it out. He assured me if it broke he would get me a new fence free of charge. So I figured it was worth a try. Worked like a charm. Since then I became a machine technician for a dealer and fixed manya fence like that. For twists I clamp one end to a sturdy bench and clamp a 2 x 4 to the other end as a lever and gradually twist it straight. It doesn't work on every fence but cast iron is more flexible than most people think. To compare cast iron to porcelain is so far off. A tap with a hammer will shatter porcelain or glass. Hitting cast iron or aluminum will yield a dent. Truly an inaccurate comparison.

[Mark Bolton]

Agreed an overly cautious comparison but I, as I'm sure you have, have seen numerous castings pushed a minuscule amount beyond "that point" and things get ugly. Same goes for alloy wheels on cars and motorcycles. I have a sanding station in my shop at the moment with the table sitting beside it because a board leaning against wall fell rather gently and caught the outer tip of the table. The table survived but the two ears on the casting that the hinge pin went through snapped off. I've got a couple mortar mixers around as well with large 20" diameter cast iron gears which suffered similar fates.

A porcelain dinner plate flexes too, just on a different scale.