Scraper Blades

[ozziebluesman]

I have no experience using scraper blades but would like to start using them in my shop.

What sizes, shape and thickness are best for use in guitar building?

The Robbie Obrien scraper video has great info on sharpening but not much on scraper size shape etc

Any tips, pictures suggestions will be appreciated.

Cheers

Alan

[Allen]

I've got your standard rectangular scraper and it's pretty good for most things. Get a good one because the edge holds up a fair bit longer than a cheap one.

I've also got a selection of thick heavy duty ones ranging from 6mm wide to 30mm. They are actually tool steel sharpened for mini planes that I need to build one day. Held about 90 degrees to the job in the finger tips they just peel off things like cured epoxy pore fill and tidy up hard to get at corners etc.

[ozziebluesman]

G'day Allen,

I bought a cheap set on ebay and they are very thick with not much give in them.

Maybe the thinner half millimeter thick blade might be better for our use?

I also will have to scrape the re-curve on my archtop at sometime in the future so I'm thinking I need something with a curve.

Cheers

Alan

[Allen]

I've got thin sets but never reach for them. The steel wasn't very good and just weren't a joy to sharpen and use. But for something like recurves on arch tops then it's probably the go. I've not got to that point, so not the one to comment on what's best there.

[DarwinStrings]

I use a .75mm (Marples I think it is) Alan and it is flexible enough for most things but a .5 would be handy too. Like Allen said get good ones as with most tool steel tools, the better the steel and tempering the better the edge will hold. A rectangle is great for most stuff but those French curvy ones are helpful too but I haven't used them on a guitar. mind you I have never made a archy. Like Allen said again, thin is harder to hook but not impossible.

Jim

[Kim]

Bacho make a very good card scraper, they come with a plastic protector which is good for storage.



Blackwoods did stock them a few years back when I bought a box of them but I don't know if they still do. If you have problems finding them let me know and we can work something out.

Cheers

Kim

[auscab]

Very good ones can be made from old saws like old Diston's ,if you have an angle grinder with the thin blades,and a linisher or belt sander, I find not much flex is better. I make all my own ,

The best burnishing tool is made from an old file, you have to anneal it [ Make soft ] then file or grind ,then polish, then re harden,you could do it in a camp fire, I have done them in the wood heater at work, and oxy and acetylene is the fastest,these are way better than the back of any tool.
I can go in to more detail if you were thinking of going down that path

After filing them they should be finished on an oil stone , the more polished and square the better
Rob

[Puff]

Glass -see your local glazier and ask for option on what he/she gets in as broken/repair.
Passed useby date bandsaw/hacksaw blades - just mount 'em in something and sharpen the back edge.

[auscab]

Just measured the thickness of the stiff ones that I think do the best on flat surfaces, all 1mm.

I have tried out these scraper planes in the past as well ,some have their uses but the basic hand held on the left is the best,much quicker to use ,with lots more edge, for big tables I would sharpen all three, and sometimes wet the wood first,keeps the scraper cool and cuts even better, cant see you dunking your guitar though

Rob

[ozziebluesman]

This Veritas set looks looks like good stuff.
Some different shapes too!
Available in 0.6 and 0.4 mm thickness.
From your responces the 0.6mm should be ideal thickness.
$19 is a good price also

http://www.carbatec.com.au/veritas-supe ... pers_c5550

Cheers

Alan

[J.F. Custom]

Hey Alan.

The Veritas ones are made in France so they are seasoned travelers having done a round the world trip to get to us! They are decent quality - especially for the price, I've got a few. The Pax are made in England and they are good too. They do actually have a reasonable edge on them "from the packet" so you can use them prior to burnishing a new edge, but of course, you can get a better burr and results yourself. The Marples are a little too expensive in my opinion for no appreciable quality difference.

As for thickness, there are considerations and eventually you will want to have a range on hand. The thinner they are, the easier on your hands and thumbs to use, but they take a finer shaving so are best suited to that. The thicker the steel, the more force is required to use and therefore the quicker your hands will fatigue. However, they are capable of a heavier cut.

There is also a scraper holder available from Veritas to save strain on your hands which is useful as they tend to cramp when used like this for extended periods. Particularly useful for those with carpal tunnel issues or similar. Of course, there is not a lot to them (the holder) so you could always make your own.

Cheers,

Jeremy.

[ozziebluesman]

Thank you eveyone for your advice.

Jeremy: I'm glad you pointed out the holder as I do have an issue with tendonitis in the left elbow from too much guitar playing over the years.

Cheers

Alan

[matthew]

And don't forget the fridge-magnet on the back of the blade to insulate your thumbs when things heat up ...

[ozziebluesman]

Yes thanks Robbie for that little gem of an idea and to you Mathew for pointing it out.

Cheers

Alan

[Clancy]

A scraper is included with the veritas holder.
Of my little collection it's the one I reach for the most (actually I've got 2 of them)

[ozziebluesman]

So what did you use to scrape the re-curve on your archtop build?

Cheers

Alan

[auscab]

The thick ones are good for leveling off the top peaks left after hand planing of flat boards after it has been planed with a smoothing plane with a slight curve in the blade,this leaves slight peaks which are taken down with the scraper kept 95%to 98% straight, and for taking down purfling and binding flat and level with sides, they are a tool for making things flat

A more flexible one would be better for taking out stains or dents but you have to watch you blend it in with the rest other wise it shows up as a dip when polished ,scrapers usually dont need to be bent as much as the Carbatec picture

The curved ones are good for getting scorch marks out ,specially on the inside, the concave curves ,good for the neck shaping.

Once you know how to sharpen one they are great but the sharp part of the blade is usually good for about ten to fifteen shaves, it starts to dull and you use the blade to the left then the right and then flip it and you have three sides left . Flat blades can be filed then to a stone, but the curved ones I just do on the linisher ,that creates a burr that works but it's a little jagged

The ones with the handles would be easier on the hand muscles,but when the blade goes dull they are a fair bit of a fiddle to re do and set up compared to the life you get out of the hand held one, plus they are ground at an angle first, same as a plane blade [? I forget the exact angle ] then a hook is formed with a burnisher,

cheers Rob

[ozziebluesman]

Rob: Thanks for taking the time to explain as I now understand much better how to use these tools. I am probably more interested in using a scraper for more fine detail work. At present I have roughed carved the back of an archtop build and I now want to refine my arch inside and out. I've never used a scraper before so now is a good time to start getting some experience using them. I did buy some 1mm shaped scraper blades off ebay but looks like I need a thinner set as well.

Cheers

Alan

[auscab]

Ah I see,
for you archtop you will need to flex quite a bit or get one the right shape or grind one , I never liked the thin ones much ,they feel more dangerous ,Ive never slipped with one or seen any one who has though, for the soft timber ,thin with the fine shaving like Jeremy said, might scrape better than trying to take a bigger bite out of soft wood.

I scrolled down at the Carbatec picture before and saw the Veritas holder, I wasn't talking about that one , I was talking about the cast one in the picture with the flat scrapers,it's a copy of the stanley 80, they are a fiddle, The holder looks good.

cheers Rob

[Lillian]

I have an old Bahco. You can't find them in the US anymore. I also have a set of Lie Nelson's and a couple of Lee Valley's. I can't say I like one more than the others. Why so many? So I don't have to stop and sharpen them when I'm doing something.

As far as thick or thin goes, I have both. I tend to use the thicker ones in the Veritas holder and the thinner ones by hand. I have issues with my left thumb and can't hold the thicker ones and flex them. The holder works nicely. If my hand is really bothering me, I'll use the thin ones in it as well.

As long as the scrapers are made of good steel, your sharpening technique is what will make them a joy to use or the reason you never use them.

[auscab]

Just did a check on the stanley 80, the blades on these are ground to 45 deg ,honed , then the hook is formed with the burnisher,

It may be that to grind a curve on the end of a rectangular scraper, and then finish it same as above ,you could get an easy to handle long scraper,that would be better for a soft wood, I'm thinking of the inside of your top. I dont know if it will be better, could be worth a try.

The normal sharpening of a scraper is not as good for soft woods as it is for hard woods, may be fine for tone woods ? but not on a lot of the standard building softwoods,

Moulding plane makers used to change the bed angle of the plane depending on whether you were working on soft woods or hard woods , joiners mainly moulded softwoods and had the common pitch at 45 degrees , cabinet makers moulded the hard woods and the bed angle was 50 to 55 degrees

cheers Rob

[vandenboom]

Two small things to add....
- if you don't have the annealing skills referred to earlier, which I don't, then consider also getting the Veritas Burnisher
- for my one and only incomplete archtop, I took a heavier rectangular scraper that I found I never used and ground a long curve on it. It was great for getting to target thickness on the undersides of top/back. I use the one with the french curves for the actual recurve - it offers a choice of radii with only slight movement as you work around the recurve contour.
Frank

[WaddyT]

My favorite rectangular scrapers are, by far, the Lie Neilson ones. Two pack, 1 thick @ .5 mm, 1 thin @ about .3 mm, for about $14 US at Woodcraft. Don't know what the on line price is, never looked, as they were available locally,, and I believe in supporting my local businesses as much as possible. The LN's seem to hold their edge better than any I've used, though I have not tried the LV ones. As to burnishers, my favorite is an old knife sharpener I got at an attic sale. It is so used, it is smooth all over, all the grooves are worn off. It's awesome. That said, a screwdriver shaft works just fine. An older screwdriver with a steel shaft, not one of the newer type with those grainy cheap finishes to make them look good.

I also have a set of little multi shaped scrapers that I have come to love. I think I got them through Vitali Imports. They weren't cheap, but the set contains 1 rectangular at about 1.5" x 1", 1 Square at about 2", a couple of small oval ones and a couple of D shaped ones. They are very useful around the neck area and working on a bridge or fingerboard.

[Kim]

My favorite burnisher is the stem of an old cylinder head valve....hard, smooth, shiny and freely available for nothing from any engine recon place and they work a treat.

Cheers

Kim

[J.F. Custom]

Yes, a good burnisher is simply smooth hardened steel - harder than the scraper you want to put the burr on. As Waddy says, many of the old screwdrivers are perfect. I don't see the point in buying a burnisher designed for the job - I'm sure they work well, but given that many items already in your workshop are likely to do the same, there seems to be little point.

Franks comment on the LV adjustable burnisher is different though. That allows you to "dial in" the angle of the rod, in this case tungsten carbide from memory I think, allowing consistency from one end of the scraper to the other, as well as whether you want a shallow fine cut, or a heavier burr for more aggressive work. The bonus is if you find you like particular angles for particular scrapers you have in your sets, or specific jobs, you can also re-create the same angle edge easily. You can simply stick some masking tape on each tool and write the preferred angle on it to remind yourself when it comes to sharpening.

Doing it without one is not overly difficult though.

Jeremy.