Old jointer blade direction

[dadpad]

I bought an old jointer. Pulled the blades and sent them off for sharpening. Now that i am ready to install the new blades I realise i have no idea which way around they should go. Arrows indicate the direction of rotation. I'd appreciate any advice.
395989395988

[auscab]

In the picture top right , spin the blade around , the sharp edge has to be coming at you , the bevel goes to the back . Blow out , and clean any dust and gunk build up so it's nice clean metal on metal when you put it back together as well . That's important for safety.
Rob

[Bohdan]

Correct orientation is with the sharp end of the blade against the "groove" in the cutter block.

There should be a packing piece which goes on the side of the blade away from the "groove".

Make sure that there is no dirt or wood residue in the cutter block when you mount the blades, give the slots a good scrub with some abrasive like fine sandpaper or steel wool.

Just be sure that you set them both to be exactly the same height and level with the outfeed table.

[Bendigo Bob]

https://www.youtube.com/watch?v=fvbfdzkPPSg that was a good primer for me when i started

[Bendigo Bob]

One extra thing, you don't need fancy expensive jigs to set the blades. As Colin in that clip says,a simple steel rule works as well as any of my gadgets :) :)

[Vann]

Your first picture is the right way around. Second picture is the wrong way around.

Cheers, Vann.

[dadpad]

Thanks all for the tips. The blades are in. I spent a bit of time cleaning the cutter block with 180 nd 240 grit sandpaper then mounted the blades. The result is a little dissapointing.

Using the steel ruler method I've set the out-feed table to where I thought it should be. I guess I can adjust the out feed table a little at a time to reduce/remove the snipe but i'm pretty concerned about the tear-out.

The blades were (very) ordinary when i sent them away so I'm not really blaming the sharpening guy but it does seem like they could use some more work.

Is the tearout and clogging of the blades a result of poor sharpening or some other problem?396027

[Bohdan]

The blades are sticking out of the cutter block too far.

The groove on the cutter is a chip breaker (the same as on a hand plane) and you have to adjust the tip of the blades to be very close to the edge of the chip breaker to minimise tearout.

A good starting point would be about 1 mm or less and then you adjust for the timber variety that you are planing. The larger the gap the more tearout but also the ability to take a larger cut.

Some of the cheaper planers don't have that range of adjustment as you need to lower the outfeed table to match the new cutter positions but if you have one of the better machines you should have no problem setting it up.

[dadpad]

The blades are sticking out of the cutter block too far.

you have to adjust the tip of the blades to be very close to the edge of the chip breaker to minimise tearout.



Hmmm, I would say the blades are fully inserted into the cuter block I cant see how the blades could be inserted any further to reduce the amount of blade tip sticking out.
I guess its possible they moved a tiny fraction as I was doing up the allen keys and also possible that there is still some gunk in the bottom of the housing but neither feel likely at this point.
Thanks for the advice. I'll definitely check those possibilities.

There isnt any blade adjustment (as far as i can see) only in feed table and out feed table adjustment

[Kuffy]

On the cutterhead, there seems to be a flat section between the blade slot and the rounded groove detail. I would not expect it to have a flat section. In your first posts photos, it looks like this flat section is a user modification such as a piece of sandpaper or similar to prevent the knives slipping out.

[dadpad]

On the cutterhead, there seems to be a flat section between the blade slot and the rounded groove detail. I would not expect it to have a flat section. In your first posts photos, it looks like this flat section is a user modification such as a piece of sandpaper or similar to prevent the knives slipping out.

I take it you are refering to396038
The sectioned outlined in this photo (left of photo). That is definitely part of the cutter head.

[Glenn.Visca]

If your cutter has gib plates ... Are they installed against the flat side (NOT bevel side ) ?

[dadpad]

If your cutter has gib plates ... Are they installed against the flat side (NOT bevel side ) ?

not 100% sure what a gib plate is but there does not appear to be any extra pieces. Just the blade and a thin spacer located on the bevel side that goes between the blade and the 4 holding allen key bolts.

I'm grateful for the offered solutions.

[Bohdan]

If the blades are fully inserted into the cutter block slots and still stick out too far then the blades are the wrong width for that particular machine.

Since the blades are manufactured in standard widths I suggest that you try to buy a set of narrower blades to fit your machine, ones that will insert into the block untill they are close to the chipbreaker groove. Machines of this type rely on the blades being ground in sets of identical width and the width being the height setting.

[dadpad]

If the blades are fully inserted into the cutter block slots and still stick out too far then the blades are the wrong width for that particular machine.

I'm now almost certain the blades do not stick out too far. I have no way of measuring but it seems less than 1mm and probably close to half mm. The blades have small amounts of the same blue paint as the body of the machine on them which leads me to believe they are originals.
I've spent an hour or so cleaning the slots with steel wool and 800 grit paper. The edge of the cutter block that the blades rest on seemed a little ordinary so i've dressed that as well with 800 grit to clean it up a little.

I also did a little dressing of the blades with a stainless steel sharpener followed by 800 grit to remove any burrs.

After reinstalling there doesn't seem to be any tear out on pine or on a stick of ironbark I tested but still tears out on that piece of redgum. I've reduced the amount i'm taking off.

All in all I feel its better but not as good as i hoped

I'm still inclined to suspect the sharpness of the blades. If anyone has a recommendation for a sharpening service in Melbourne or surrounds I'd appreciate it.

Thanks for all the replys and suggestions thus far.

[auscab]

When I did get mine back from having them ground (these days I grind my own ) I sharpen them on a stone same as a chisel . As far as I know, most of the sharpening services give them back finished on the grinding wheel , not honed .

[Glenn.Visca]

My family has used these guys for many many years ...

https://g.co/kgs/S3yu8g

[dadpad]

I spent today truing up the feed tables..... or at least trying to. Quite a frustrating excercise. The feed out table now droops about 4 thou in the last 3 or 4 inches perhaps 5 thou at the very end according to my straight edge and a set of feeler guages. Is it necessary to have it better than that? I suspect i'll have to shim it if it needs to be more accurate.
After that I reset the blade heights so they move the straight edge 5mm.

99% of the tearout is gone but still getting snipe something cronic that no amount of adjustment to the feed in table is able to fix. It may be my technique but I'll have a look at some more vids and see what i can do about it.

[auscab]

keep raising the out feed table tiny amounts until the snipe is gone.
If the snipe is happening at the end of a pass, at the end of the board, the end of your wood is dropping off the front table down to the level of the back table.
A straight edge is used when setting up the blade height to the back table . The real test as to how good it is, is how it cuts the wood.
If you go to far when raising the back table to get rid of snipe , you start to get a strange effect where no matter how many times you pass a board across, trying to take a cut, you cant get a full cut, it wont do it . So you have to lower the back table a tiny bit . .
That's how I get my buzzer working well any way .
When I do have a straight edge on the back table testing the height of the blade as I'm installing it , I don't think it would lift the blade and shift it 5mm forward , more like just kiss it, and not move the blade , at both ends of the blade. Do this to both the blades and then the back table adjustment is done after taking test cuts.

Rob