Using a planer

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lenarenee

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Just how hard should it be to use a planer - and get a smooth soap? I've practiced on 3 bars of soap - two are 6 weeks cured, and one is 2 weeks.
Now all of them are much thinner than they used to be, and I don't have a smooth surface yet. There's waves or ripples that seem to happen about half an inch after the bar passes over the blade

Is there a trick to this or is it time to contact the maker?
 

lenarenee

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Yeah I left that important info out didn't I?

It's from Plowboyz [ame]https://www.youtube.com/watch?v=B_8F2VWJBPM[/ame]

By the way IrishLass - I want to give you a great big thank you for sharing your salt bar recipe! I've made 5 lbs of it over the weekend - my first time ever. Sure is going to be difficult to wait to give it a try!
 

dibbles

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I have that planer and it seems to work best if you don't press/apply pressure while you are passing the soap over the blade. Just gentle fingertips to keep it in place. There is a learning curve, but you will get the feel of it. HTH
 

lenarenee

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I practiced again with another bar (however, this one is several months old.) The blade digs into the bar once the bar passes over the blade and and dips down (about 1/2 - 1 inch). Also, as I get near the end of the soap I get ripples.

I'm still practicing, but right now my impression is that the blade is a little too high.
 

DeeAnna

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The side of the planer that the soap bar starts on is called the infeed table. The side of the planer that the bar ends on is the outfeed table. The annoying wavy divot at the end of the cut is called "snipe". Don't ask me why -- I haven't a clue! :)

I don't have that particular soap planer, but I've done woodworking and used planers and jointers for years. The methods translate pretty well from wood to soap.

Obviously you have to put some pressure to push the bar into the blade, but you also need to put moderately firm pressure down on the top of the bar at all times. This keeps the soap bar flat against the table. The downward pressure should be about the same amount of force as the sideways pressure.

First, start the bar into the planer blade. All of the downward pressure will obviously be on the infeed table at this point. As soon as the bar gets about halfway through the cut, however, shift where you are pushing down so more of the pressure is on the front third of the bar.

This means during the last half of the cut, ALL downward pressure will be on the soap lying on the outfeed table. Don't put any pressure on the soap that is lying on the infeed table. You may need to experiment with how to place your hand so you get the right amount of downward pressure on the right spot on the bar.

This should reduce the "snipe" at the end of the cut, but may not eliminate it.

To reduce the snipe further, try putting the bar through the cutter at a slight angle, so the cutter blade exits from the soap a little bit at a time, rather than all at once.

ETA: My soap planer takes off a shaving so thin it's translucent -- two passes to clean up the front and back faces remove only 3 grams of soap. If yours is removing a fair bit more than that, then, yeah, the blade may be too high.
 
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IrishLass

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That looks like a really nice planer! I have the acrylic planer from Soapmaking Resources myself.

I'm not sure if that safety-slider will allow you to do so or not, but are you able to push the soap over the blade at an angle (from one corner of the soap to the opposite corner) instead of straight-on like he shows in the video? If so, I think you may get a better plane/slice. That was the advice given to me from other planer users and it has served me quite well.

Also- something else to consider- I'm wondering how much the safety-slider mechanism interferes with the amount of even pressure you are able to exert on the soap as you pass it over the blade. I'm just wondering because I don't have a safety-slider on mine and I am able to get really good, even pressure control by having the whole balance of my hand on the soap instead of just the forward part of my hand. Do you feel like you'd have better, even pressure control without it?

The only other thing I can think of whether or not blade bows when you slide the soap across?


IrishLass :)

Edited to add: Didn't see DeeAnna's post until after I posted. lol
 
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lenarenee

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Thank you all - I'm going to put your info into practice later (time to pick up my little one from school). The people on YouTube make planing look so simple - just scrape over a couple times and you're done

IrishLass I was wondering the same thing about the safety panel. it at least causes a different dynamic in the learning curve since you can't really sense what your hand is doing. And I'll try the angle thing too.
 

DeeAnna

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"...The people on YouTube make planing look so simple - just scrape over a couple times and you're done..."

I noticed he is not getting a full shaving when he passes the large face of the soap over the planer. The worst snipe is going to be when you're taking off a full shaving. That might be why he can make it look so easy?
 

lenarenee

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"...The people on YouTube make planing look so simple - just scrape over a couple times and you're done..."

I noticed he is not getting a full shaving when he passes the large face of the soap over the planer. The worst snipe is going to be when you're taking off a full shaving. That might be why he can make it look so easy?

Aha! Is that what my problem is? I was pushing the bar in a manner where I assume the lion's share of the straightening would be on the planer....where it would catch the thicker part of the soap and just take that off and not touch the rest. Is it better to plane so that a whole layer is taken off at once? (Did I explain that well?)
 

DeeAnna

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Yes, you did good! :)

A planer is designed to (1) remove material to make a flat surface and then (2) to take an even slice of soap off that flat face. A planer won't do well if you want it to make a tapered cut as if to make one face parallel to the opposite face. Parallel, consistent cuts are the job of a soap bar cutter. The planer is supposed to just tidy up.

If you push harder on one end to make the planer cut deeper on that end and cut more thinly at the other end, you may be able to force the planer to make a slightly tapered cut, but it's also going to be harder to control the quality of that cut.
 

federalist

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If planing soap is anything like joining wood... it's important to apply even pressure to the top of the soap in order to keep it flat against the planer bed. If you are having difficulty doing so by hand, you can try using a push-block. They are easy to make or buy, and they prevent your hands from coming into contact with the blade, eliminating the need for the safety-slider.

 

DeeAnna

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A push block is helpful, but if you are planing a short item and you only push down on the part that lies on the infeed table, it can be tough to avoid getting some snipe. The downward pressure needs to shift more to the outfeed table to keep the item stable -- again I want to stress this is more important for a short item such as a bar of soap than for a long board.

This tendency to snipe is harder to control on a soap planer because the outfeed and infeed tables lie in the same plane with respect to each other, but the soap itself does not remain flat as it passes over the cutter -- the soap is slightly thicker on the infeed side and slightly thinner on the outfeed. Somewhere in the process of planing off a shaving, you need to account for this effect. If it all happens at the end of a cut, there's your snipe! On a wood planer, the outfeed table is slightly higher than the infeed table to account for the stock removed by the planer's cutter so the chance of snipe is less.
 

songwind

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On a related note, I'd be curious to know if anyone here has tried using either 1) a hand plane, or in sort of the opposite direction, 2) a kitchen mandoline/v-slicer for this?
 

cgpeanut

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I was just thinking about trying my mandoline. I like the idea of being able to adjust the blade. Especially when you do top swirling and your soap has gotten too thick. I thought it would be easier to have an adjustable blade.
 

DeeAnna

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I've used both. A mandoline is not able to be set to a fine shaving you would normally want. If you want to make thick curls for a project, it might be okay. A plane works well, but is too narrow for most bars of soap. I also don't like the idea of using soap with an expensive plane that is not intended for use on high pH things.
 

federalist

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Me too; I would hate to see a nice hand-plane used on soap. Most hand-planes are made with wooden handles; some have wooden bases. These wooden parts would be consumed over time by lye.

I cannot express how precious some older hand-planes are. The wood, casting techniques, craftsmen, and manufacturing facilities needed to produce an old hand-plane don't exist anymore. If you destroy an old hand-plane, there is nothing that can replace it. :(

Sure, you can shell out $200 for a shiny new Lie-Nielsen. Or buy a useless hand-plane shaped object for $40 at Home Depot. I would stick with a soap-plane.
 

DeeAnna

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"...useless hand-plane shaped object..."

<snort!> Too true! Well said....
 
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