Question about planing. Are there any who are experianced at running Planers?

I have several parts that are longer then the stroke on my planer.
I need to plane the full length of the part. I am limited on how to use this machine but this job would be a good one to do on it. the parts are 84 inches long and are planed 5/16 deep on the flat and come out with a 45 degree angle the full length of the part. The stroke on my planer is only 6o inches. What is the best way to do this? I know my tool needs a place to clear on both ends of the stroke.

Planers are usually handled over in the Antique machinery forum.

Does your application allow for an interrupted surface? You might be able to cut a clearance notch in the middle for tool clearance at the end of the stroke and do 60" off the work, then shift the piece and finish the remaining 24 inches. If you can set a stop for the horizontal travel of the tool you should be able to get very close.

Where's Forrest Addy?

L7

What tolerances are you working to ?

Regards Tyrone.

"I know my tool needs a place to clear on both ends of the stroke."

If you convert the machine to a planer mill by adding a Bridgeport head to it, you can carefully relocate the work on the table and do the job with two cuts. No need for a gap between cuts.

Larry

About the only way you could do this without cutting a clearance notch would be if you had excess width on the table so that you could set the work at an angle. But then you'd be adding a lot of unnecessary time to the job. Better to try Larry's idea or send it out if your machine doesn't have the necessary travel.

L Vanice said:

"I know my tool needs a place to clear on both ends of the stroke."

If you convert the machine to a planer mill by adding a Bridgeport head to it, you can carefully relocate the work on the table and do the job with two cuts. No need for a gap between cuts.

Larry

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Lotta work though. Bolting the B'port head on is the easy bit, replacing the table drive with a big ball screw or similar is a lot more aggravation.

I have a planer with missing table drive components and a spare B/port head so I've given this some thought....

PDW

PDW said:

Lotta work though. Bolting the B'port head on is the easy bit, replacing the table drive with a big ball screw or similar is a lot more aggravation.

I have a planer with missing table drive components and a spare B/port head so I've given this some thought....

PDW

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There are other ways to slow the table drive on a planer, if it has one. For instance, you can throttle back the steam engine or put a larger pulley on the planer.

Larry

PDW said:

Lotta work though. Bolting the B'port head on is the easy bit, replacing the table drive with a big ball screw or similar is a lot more aggravation.

I have a planer with missing table drive components and a spare B/port head so I've given this some thought....

PDW

Click to expand...

There's a bit more to it than that. Planing is very forgiving of certain misalignments in your machine, milling isn't. For instance If the columns/uprights are leaning forward a bit causing the cross rail and toolboxes to lean forward also it won't affect planing at all. However if your milling head is leaning forward you will create a scalloped finish in your work. That's just one example.

Regards Tyrone.

Tyrone Shoelaces said:

There's a bit more to it than that. Planing is very forgiving of certain misalignments in your machine, milling isn't. For instance If the columns/uprights are leaning forward a bit causing the cross rail and toolboxes to lean forward also it won't affect planing at all. However if your milling head is leaning forward you will create a scalloped finish in your work. That's just one example.

Regards Tyrone.

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Bolting the B/port head on is still the easy bit though. Aligning it is another problem. Slowing the table feed *and* getting the feed speed working nicely is non-trivial. Not to mention positioning control, which by default planers don't do well.

I like the comment about just bolting on a bigger pulley. Sure, let me know how that works out for you and what effect it has. If you can find something suitable that is. My working planer has 400mm diameter cast iron pulleys, I've recently had it apart to fit bronze bushes to them. Ended up being a nice job for the baby Kearns HBM to line-bore the pulley/gear assembly.

PDW

Back to the OP original question.

It's really no big deal planing a work piece that is longer than the stroke of your planer. Just have to do some pre-planing to make sure everything will out.
When I had my planer which was a 72" stroke Cincinnati DH planer, yeah, small compared to it's big sisters being made, I took on a job that I lost my ass on, planing two sides of an rectangular casting that was around 80" long. They only wanted two sides machined, the other two were left as cast. They weren't the prettiest looking castings either. Set the job up on a set of parallels where it balanced on more or less four corners, with one or two corners shimmed so it pulled down without twisting. Next set up my planning tool to plane the top surface, rougher and a broad nose finisher. Then set up a vertical tool to plane one side down about 1" and stopped. You do not need a relief at the end of the cut, the cutting tool would raise up a tad on the return stroke. Remember, using Rex 95 here or was that Mo-Max, I don't remember. It was HSS regardless.

Next, I slid the work piece forward enough to finish cutting the rest of the piece of the iron. Re-clamped, rigged up an indicator to indicate in on the just finished planed surfaces. Once done picked up the cut to roughen, then come up behind with the broad nose tool to clean up and match plane to the previous cut. Not had to do, you can get it within a quarter to half an thousandth or better. Just takes practice. Been nice to have a milling head mounted to the old planer back then, just too slow, that was the reason I lost my a$$ on the job!

And I've mentioned this before, I've seen this done long machine beds, that had several bed sections bolted together making up a length of over 120 feet in length. It can be done.

Ken

Thanks Ken for your response. I still do not get what you are trying to say, when at the end of the stroke the tool will lift up on the return stroke. I am trying to do this at .312 depth and .005 to .01 across per stroke traveling 15/16 across part. The part is 84.00 long. I have 60.00 of travel on my planer. How do I keep from breaking the tool. Do I need to shift the part back and forth or do I rough out 60.00 first then slide the part forward to rough the last 24.00 and repeat this on the finish pass.

If you're using carbide to cut with, toss it out and get you a piece of HSS to cut with. On the return stroke, the cutting edge will automatically lift up slightly. Will not hurt the cutting edge. It lifts up probably no more than .020-.030", just enough so it doesn't drag directly on the cutting edge. The clearance under the cutting edge need not be more than about 3 degrees clearance. Anymore than this, it won't lift up properly and will dull the cutting edge quickly. Be sure to hone the cutting edge too. I assume your planer has a clapper block type of tool post? Please remember, I haven't been around a planer in almost 40 years. So a lot of what I said is from my fading memory. Ken

You can lift your tool at the exact same place every time with a lever sticking up on the toolholder and a cam at the end of the stroke which lifts the tool with that lever So the tool cuts a radius going out of the work There is also a mecanism that can keeps the tool retracted all the lengt of the return stroke Dont remermber how that was
That was on a shaper with a rotating head where the workpiece rotated at the return stroke So the tool had to be cleared from the work They made grinding cylinders for industrial coffeegrinders on these from white CI


Peter

hope said:

I still do not get what you are trying to say, when at the end of the stroke the tool will lift up on the return stroke.

Click to expand...

Edumacate yerself, then.

Google "clapper box", find definitions, drawings, and you-tube videos illustrating how they work on shapers and planers, "usually", slotters only sometimes - plus a few other reciprocating critters that power-operated wood chisels, mortisers, and such to make wagon-wheel hub slots for spokes in days gone by.

Sometimes they are locked. Sometimes they are even missing.

But it is the simplest of "physics" in-use when present.

- Pressure of the cut holds an advancing tool DOWN,

- modest heel-drag lifts a retracting tool UP.

Repeat strokes until done.

Page Two:

Out of 84" as two runs on a 60" shaper?

You won't want 60", then 24".

More like 48"+48" with an intentional overlap zone right at center to manage the transition.

And...

Shallow cuts = weaker chips that snap-off and clear better than thick ones, so less risk of build-up and unwanted deflection of the cutter at the end of a "blind" stroke.

Patience is your most reliable tool.

thermite said:

patience is your most reliable tool.

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fact ^^^^^^^

thermite said:

Patience is your most reliable tool.

Click to expand...

If you spend much time running a planer, you'll either have it or you'll get it......

PDW

Haven't had the pleasure of running a planer but have lots of time on a 26" stroke shaper. Love it, but yes to patience!

L7

If it was I, the depth of cut would be 3 or 4 passes to get the 5/16 depth of cut. Then with each successive pass I'd back the table return dog by another 1/2".

gbent said:

If it was I, the depth of cut would be 3 or 4 passes to get the 5/16 depth of cut. Then with each successive pass I'd back the table return dog by another 1/2".

Click to expand...

+1

Biggest challenge I see is that overlapping successfully REALLY wants an extremely high degree of familiarity with the particular planer (or shaper, or mill..) and all of its little quirks, imperfections, and deflections. AND, of course the metrology, experience, and clamping skill to successfully set-up to match and maintain the "plane" in the cut. A trio of "non-trivial" exercises, co-joined, if you will.

Some here (not I...) have that - near-as-dammit "married" to their particular machine(s) for long years and many taskings, so they have "BTDTGTTS".

The "miss" on clapper-box action suggests the OP may not have that level of comfort?

Might be better advised to send this task off to some other shop - especially if the workpiece has significant value, a tight deadline, or is not readily replaced - cheap or dear.

He who knows his limitations (guilty!) - as well as those of his tools - at least has the advantage over some more confident Pilgrim who admits of fewer. A cautious man finds lower-risk ways in advance to work around those limitations.

2CW