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first time with scary sharp method, didn't quite work, what's wrong?

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Forum topic by Spikes posted 10-29-2018 10:05 PM 3406 views 2 times favorited 30 replies Add to Favorites Watch
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Spikes

96 posts in 245 days


10-29-2018 10:05 PM

Hi,

so I asked about sharpening tools with diamond plates in another thread thinking that’d be the way to go, however my conclusion from that conversation was that the scary sharp system was a good place to start, cheaper to get into and more forgiving with mistake, plus I could start right away just buy getting some wet dry sandpaper from the local auto parts store.

Here’s what I got:
- laminated mdf bed
- tempered glass from a scanner bed
- wet dry silicon carbide sand paper (100, 400, 800, 1000, 1200, 1500, 2000)

Chisels to sharpen:
- one very hold chisel, totally beaten up (could not cut any wood at all)
- one irwin marple chisel bought new (could not cut a mortise in pine, but could take some rough shavings with a lot of force)

What I’ve done:
- put a sheet of paper at a time on the glass resting on the mdf
- while holding the paper drag the chisel backwards 10 times per sheet, dragging for about 6 inches more or less always on the same spot of the paper
- after dragging the bevel flip the chisel and use another spot of the paper to lap the back
- could not feel any burr

Results:
- both chisels are shiny
- the one that wasn’t cutting barely cuts, but really can’t deal with a 2×4 end grain (went all the way from 100 to 2000)
- the irwin can make some dents in the end grain altho lots of tearout but cuts quite nicely along the grain (much better than before sharpening and since it already had a flat bevel I only did 1000 – 2000). Definitely cannot shave the hair on my hand like they show in the sharpening videos…

Questions:
1) first off, some videos spray water on the sandpaper, some say to absolutely not to, which one should I follow? no water would be cleaner but…
2) the sand paper seems to clog and become basically useless after just a couple pulls, maybe the water would help with that?
3) some people say to pull only to avoid tearout, but many videos I’ve seen go back and forth, is one better than the other?
4) how many times should one stroke the paper? 10 seemed a decent number, but maybe I’m just going too fast? I just don’t wanna wear out the chisel and I’ve read that if you go at it too much you actually lose the edge you had just put on it.
5) should I do the back only at the very end or after each grit of paper? I’ve seen both and it’s not clear which one is right/better if either

anything else I’m missing? also I don’t have a strop or strop compound because some threads said it’s needed, some said you don’t and since I don’t have a lot of cash I thought I’d try first without.

thank you for all the feedback.

-- Don't worry about making progress, worry about practicing. If you practice you will make progress even if you don't want to.


30 replies so far

View chrisstef's profile

chrisstef

17761 posts in 3206 days


#1 posted 10-29-2018 11:15 PM

Start with making the back flat first. Work it all the way up to 2000. A flat back is of utmost importance. Then we’ll work on the bevel.

You can use a paint brush to get rid of the metal filings clogging up your paper.

Use as many strokes as it takes to create a burr.

-- Its not a crack, its a casting imperfection.

View Nubsnstubs's profile

Nubsnstubs

1422 posts in 1929 days


#2 posted 10-29-2018 11:15 PM

If you can’t find a plug on that MDF, you need to toss it and go get yourself something that has a cord on it. Then you can sharpen to your heart’s content….... Jerry (in Tucson)

-- Jerry (in Tucson) www.woodturnerstools.com

View Richard Lee's profile

Richard Lee

196 posts in 975 days


#3 posted 10-29-2018 11:40 PM

Keeping your blade at the same angle and straight by hand can be tricky,try something like this.
http://www.leevalley.com/us/wood/page.aspx?p=32968&cat=1,43072,45936
I use this paper http://www.leevalley.com/us/wood/page.aspx?p=68943&cat=1,43072

View OSU55's profile

OSU55

1964 posts in 2189 days


#4 posted 10-30-2018 12:08 AM

Using the scary sharp method to get the back flat is a pita – regulR wet/ dry paper has enough give in it to slightly round the edge. I check fltness with ~ 320-400 grit to assess how far out the surface is. Sometimes then go to 60 or stay where I am or anywhere in between, its a judgement and I guess wrong at times. Up to ~120 use sanding belts and dont put much down force (rounds the edges). Use a shop vac or brush to clean the paper. At ~220 I start using water. To actually polish the surface I use polishing film 25 um down to 1 um. You can move the surface back and forth, you arent using a lot of downforce.

For primary bevels get a bench grinder. Then free hand or use a jig (I prefer jigs because I use the film and put microbevels on the edge). I use a back and forth motion. I polish to 1 um, no stropping. Strops work, especially to tune a good edge starting to dull, but strops also sharpen lower grit edges which are jagged and fail quickly due to microfractures of the sharp jagged edge. Strops used to break burrs retain the metal and scratch the edge. You will find many opinions on sharpening, strops, etc.

You may find something helpful in my sharpening blog

View ocean's profile

ocean

121 posts in 1033 days


#5 posted 10-30-2018 12:26 AM

Flatten the back first. Personnel I stop at 800 or 1000, but your welcome to go on out to 2000, it is just how much time you wish to invest. Shiny does not mean sharp. If you don’t own a chisel guide, get one. The Lee Valley is nice but a bit expensive. Try one from General or the clones available form lots of places, about $15-16.00. Just brush off the filings from the paper. I do go back and forth many times as needed (no set number). Final test is to place the chisel straight up against your thumb nail (at about a 45 degree angle or more down) and if it catches on your nail and stays in place it is sharp enough. Future sharpenings will only require to you to start at the higher grits unless you have chipped the edge or they are really dull, like dropping on the concrete floor blade down. Cutting end grain is very difficult for any sharp chisel. Don’t let that be your soul bench mark of a dull chisel.

-- Bob, FL Keys

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BlasterStumps

982 posts in 639 days


#6 posted 10-30-2018 12:36 AM

I use sand paper for the beginning stages of sharpening. I have interchangeable discs with different grits that I can put on a low RPM motor that is mounted vertical in a box. I touch the tool on the spinning disc for a second or two then cool with water then touch again and so on. Once I get the angle and work thru to 320 grit, I go to my diamond stone and work it thru to 1200, then I rub it on an 8000 water stone for a few strokes and then to a stope that is also on a disc on that low RPM motor. The whole process to sharpen a chisel or blade is only a matter of a few minutes unless the tool has been badly damaged.

-- "I build for function first, looks second. Most times I never get around to looks." - Mike, western Colorado

View msinc's profile

msinc

569 posts in 703 days


#7 posted 10-30-2018 03:16 AM


If you can t find a plug on that MDF, you need to toss it and go get yourself something that has a cord on it. Then you can sharpen to your heart s content….... Jerry (in Tucson)

- Nubsnstubs

This!!!


Keeping your blade at the same angle and straight by hand can be tricky,try something like this.
http://www.leevalley.com/us/wood/page.aspx?p=32968&cat=1,43072,45936
I use this paper http://www.leevalley.com/us/wood/page.aspx?p=68943&cat=1,43072

- Richard Lee

And this!!!! After you have the chisels ready to actually start honing.

One of the problems with all this free advice regarding a certain method is that often the posters don’t do too good a job explaining at what point their chisels are actually at when they begin the “method”. I seriously don’t believe anyone means for you to start out with sandpaper {or a hone} to try and sharpen a chisel that has seen better days and first needs to go on a grinder to get it close to going on the paper.
Given the state of the chisels you are describing, there is zero chance I would start out with paper or a hone. I usually begin with a power grinder to get them close. Then I start honing with the rough stones and finish with a razor hone. Now, I could take a gunched up chisel and given enough time, strokes and single malt get it to cut with just the razor hone….but I wouldn’t recommend trying it!!!
It sounds like what you have done so far is along these lines and given enough time and elbow grease it might have worked…but, if you really insist on wasting all that time it sure would be better spent with the use of some type of edge guide.

Edit: water works as a honing lube…but honing oil is way better…lacking that I use some type of light oil like WD-40. Not the best, but it will do and is better than water.

View jeffgao's profile

jeffgao

10 posts in 52 days


#8 posted 10-30-2018 05:01 AM

I have prepared newly purchased Irwin chisels using sandpapers with success. Comparing between what I have done and what you did, I guess you can look into these:

  1. Like other people already pointed out, work on the back first to polish it up. Regardless of the concerns on sandpaper’s give (whether you have a rounded back or not), you should end up with a mirror finish on the back that allows you to have a good edge.
  2. Going directly from 100 to 400 is probably too much of a gap. You can have 220 as the second step after 100, or have 220 as the first step if there is no significant chip. Also, you could keep 1000 and 1500 and eliminate 1200 and 2000. 1500 should give you enough sharpness – that’s the highest grit I stopped for my chisels.
  3. For steps before the final step, especially steps below 1000, feeling no burr is wrong. That actually means you have never created a consistent burr yet. You should only move on to the next step after you feel a consistent burr across the edge.
  4. Use a honing guide. A cheap $10 Eclipse type will do.
View Manitario's profile

Manitario

2681 posts in 3082 days


#9 posted 10-30-2018 08:32 AM

Lots of great advice so far. Most of us learned to sharpen with the “Scary Sharp” method. Like most beginners, it’s easy to over think something that is simple.
1)Flatten and polish the back; use the coarsest grit until you have an even scratch pattern on the back. Then move up to the next grip and repeat.
2)Do yourself a favour as a beginner and get a honing guide. It adds <10 seconds to the sharpening process and will give you consistent results. If later you want to learn to freehand sharpen, great, at least you have a reliable method for sharpening to fall back on.
3)Sharpen the bevel with your coarsest grit until you have an even pattern of scratches and an even burr. Move up a grit and repeat.
4)Enjoy having sharp tools.

-- Sometimes the creative process requires foul language. -- Charles Neil

View CaptainKlutz's profile

CaptainKlutz

601 posts in 1694 days


#10 posted 10-30-2018 08:48 AM

+1 Use an edge guide, takes a tremendous amount of skill to free hand sharpen a blade to a specific angle. Attempting to learn freehand method while you learn how to make a sharp edge can be very frustrating.

+1 Must develop a burr on the edge before gong to next grit. Typical burr is thinner than human hair. It is much easier to feel the burr, then see a burr on edge (unless you have 10-15x magnifier handy). Using a magnifier can also help you see edge sharpness, as dull rounded edge will reflect light and look shiny, but a sharp pointed edge is almost invisible.

+1 Process is important.
Flatten and polish the back first, going through all grits till last 1/2 to 1 inch of blade is flat. Then sharpen front edge.

The reason for recommendation to only use pull stroke is to help avoid breaking off the edge burr as you push the blade forward. Only takes a subtle lift on back end of blade during push stroke, and you grind the burr off = making a dull rounded edge. Once you learn how to keep the blade angle exactly same during both pull and push; then you can attempt push stroke – otherwise use pull only.
Note that if your sandpaper is not bonded perfectly to glass, or backing paper has swelled due lubricants; that can allow grit surface to move slightly. When using a push stoke, if the paper moves/indents ahead of blade due excess pressure; you end up removing the burr and rounding the edge on push stroke – even if using an edge guide. Wet/Dry paper absorbs oil slower than water, so best to use light machine oil or ATF as lubricant .vs. water. Lubricant absorption and movement is also reason that plastic film backing is used for expensive super fine diamond grit materials suggested by Richard Lee.

FWIW – Your posted challenges making a sharp edge are the exact reason I posted in other thread to start with cheapest option – sandpaper. Making a sharp edge requires knowledge, patience, and practice. Once you figure it out, making sharp edges will become easy with any method you choose to use. :)

Best Luck.

-- I'm an engineer not a woodworker, but I can randomly find useful tools and furniture inside a pile of lumber!

View Max™'s profile

Max™

44 posts in 109 days


#11 posted 10-30-2018 08:51 AM

I wonder why it took so long until I saw someone suggest sideways strokes for chisel/plane sharpening by hand?

After doing it myself, might just be my setup but for me at least, it’s a lot easier to maintain or tweak an angle when you’re skating something sideways towards/away from you than it is if you’re moving it edge-first towards/edge-dragging away from you.

I’m generally seated down low when I’m sharpening so I can watch the angle itself, and after trying straight back/forth strokes, various circle or figure-8 strokes, and then switching to side-to-side strokes, it is a lot less work for me to maintain an edge.

Helped me realize I was actually going way too far when I was pushing the edge along the paper, repeatedly forming and overshaping past the edge when I could reach my desired shape in a handful of strokes per grit.

-- One hand to hold the saw, one hand to guide it, one hand to brace the work and in the sawdust OW MY THUMB!

View therealSteveN's profile

therealSteveN

1685 posts in 774 days


#12 posted 10-30-2018 09:29 AM

If you can find one on E-Bay I would suggest getting a Sharp Skate sharpening guide here Derrick shows a very good review

Harrelson Stanley is still selling them through HMS, but jeeze, they are several hundred dollars, which is crazy money. They work side to side on 8 tiny rollers, the action is very smooth, and you can set your angle to get perfection. So many of the back and forth guides can/will allow you to tip the guide up, and or down, which muddles your edge.

The order you have been given is correct, always do the backs first until you get a uniform sheen all across the back, work through all the grits first pass, then swap to your bevel. Once you have established sharp, you are routinely going back to touch up at the higher grits to stay sharp.

One truth about tool steel is, cheap is junk, sure you can get it sharp, but the amount of time it stays that way is very short. Good steel and that time period between sharpening will expand with increased outlay of dollars. I really like the LV PM-VII

Another sometimes lower priced chisel that cuts very well are the Japanese chisels. Ignore the convex backs, and sharpen the same as an English chisel.

Once you learn a good edge, look into a micro bevel, sharper, yet only a tip in length, and easier to repair when you dull them out.

Personally I really suggest you get a WorkSharp 3000, and put all the other behind you.

-- Think safe, be safe

View fuigb's profile

fuigb

522 posts in 3157 days


#13 posted 10-30-2018 11:25 AM

Very good advice in this thread!

I agree that flattening and polishing the back is important as is a decent guide. What I emphasize is getting the edge right. With a badly used chisel it might take an hour or two of concerted effort to create a uniform edge using only 100 grit paper. Don’t take at face value the demo vids where the guy goes from dull to razor sharp in 90 seconds because a ton of time might be necessary before the actual sharpening begins. Many of my favorite and most-used chisels were bought as basket-cases found at estate sales for 50 cents; hours of work later and the former scrap gleams and slices through hard maple like nobody’s business.

-- - Crud. Go tell your mother that I need a Band-aid.

View rwe2156's profile

rwe2156

3170 posts in 1680 days


#14 posted 10-30-2018 02:20 PM

- could not feel any burr

This indicates you need a coarser grit or more strokes.

I don’t use sandpaper but the principle is the same: No burr, don’t move to next grit.

Are you doing a secondary bevel?

Also, the grits for sandpaper, water stones and diamond stones do not translate.

I go to 8000 on a water stone. A lot of guys to to 16000. That may translates to a lot higher than 2000 in sandpaper. Somewhere I saw a chart comparing grits for paper & stones.

-- Everything is a prototype thats why its one of a kind!!

View a1Jim's profile

a1Jim

117328 posts in 3777 days


#15 posted 10-30-2018 03:18 PM

I use to use the scary sharp method for years before switching to a worksharp 3000 F, reading this thread seems to me that this process is being over complicated as others have said holding the chisel at the correct angle is important so if you can’t do that the buy a guide,as other have said you need to flatten the back of the chisel. I use every grit from 60-600 but only start that low of grit if your chisel is in very poor condition with big chips or damaged edge or start at a bench grinder to get rid of very rough chisels. Just use spray adhesive to hold each grit of sandpaper on a piece of MDF large enough to glue one piece of sandpaper of each grit using both sides then start with the lowest grit necessary to get any chips smoothed away concentrate on getting a straight smooth edge if there are only small chips you may be able to start at 100 or 120 grit .
There is no magic number of times you have to strokes the sandpaper only until the edge is all even then move through all the grits to at least 600 or higher if you like ,where many people miss out in this process is trying to zoom through all the grits or skip some grits without getting the defects out or getting the edge done before moving through the grit as you go finer and finer it takes less time for each finer grit. In my opinion, you don’t need to use water or look for burrs I think this can drive a person crazy that is just getting into the scary sharp system constantly checking for burrs. If you just can’t get this process buy a Worksharp 3000 it makes sharping a lot easier.

-- https://www.artisticwoodstudio.com/videos wood crafting & woodworking classes

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