Do-it-yourself professional diamond blade scraper. How to make a two-handed straight staple from a cut-off wheel Cooper one-hand staples
Perhaps the most difficult task for a novice cooper, who undertook to collect all necessary tool for his workshop, is the manufacture of cooperage brackets. This question is far from being as simple as it seems at first glance, and if there is no experienced master-mentor nearby with his own set of tools, then you can get into a mess by making braces with incorrect parameters, which will be impossible to use.
In general, the scraper is a universal tool. Once upon a time in Russia they were used instead of planes. One and the same scraper can both "drive the chips" from the workpiece, and remove the transparent thinnest chips from it. But for different purposes, different brackets were made. So, for example, a straight scraper, with which carpenters hew and scrape logs, is completely unsuitable for coopers. It's all about two important parameters that determine the functionality of the staple. This is the angle between the plane of the blade and the plane of the handles, as well as the angle between the handles themselves.
Straight cooper scraper
A straight cooper's staple is usually used to plan the outer face of a rivet on a cooper's bench. It can also be used to chamfer the bottom or the end of the product. In accordance with the type of work, straight staples can have different blade lengths.
Sketch No. 1 shows the optimal spreading angle of the handles of such a staple. Pay attention to the most important condition: the plane of the blade and the plane of the handles must be parallel! (shown in the left view).
Bracket "Zhelobikha"
Honestly, I only use the straight staple for chamfering. It is not very convenient for them to detach the outer surface of the rivets, especially if it is wide. It is much more convenient to work with another tool - a "chute" scraper.
Sketch No. 2 shows its main parameters. Pay special attention to condition # 1: the centerlines of the handles must intersect the level line of the top of the cutting arc... Thanks to this, the staple works "in both directions", that is, it can be used to process both the outer and inner faces of the rivets!
There are two ways to process the gutter on the outer surface of the rivets on the cooper's bench - both with the concave (in relation to the master) side and the convex one. In the first case, the chute works on the principle of a scherhebel plane, providing a quick rough cutting of the workpiece. In the second, it forms a semicircular surface, which will only have to be brought to mind with a joiner jointer. The concave side of the groove can be used to process the inner face of the rivet. Roughing of rivets with a groove is faster than an electric planer.
It is also convenient to use the chute for stripping and debarking wooden hoops.
In my workshop there are only two standard sizes of gutters (indicated on sketch No. 2). Big, I plan rivets of any width and for any diameter of tubs. Well, the smaller one is used exclusively for hoops.
Improved semi-circular cooper scraper
Semicircular staples are used when processing the inner surfaces of tub frames. For any semi-circular staple, it is important to observe optimal slope handles, shown in sketch No. 3. Better to make the handles parallel between themselves, otherwise when scraping you will knock on the edges of the skeleton of the wrist and hand.
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A conventional semicircular staple with a constant bending radius of the web has a significant drawback. If you make its radius close to the inner radius of the tub, then its edges will touch the inner surface of the frame where it is not necessary at all, including on the already processed and cleaned side. If you reduce the radius of the scraper, then it will work like a scherhebel plane, leaving after each pass a groove that still needs to be removed somehow.
Therefore, it is better to make the curvature radius of the canvas variable. In its central part, the radius is large, close to the parameters of the skeletons of your tubs, and at the edges - reduced. Such steeply rounded edges will never touch, and inner surface will be smooth enough.
The staple with the parameters indicated in sketch No. 3 is my most popular one. It is the smallest, but with its help I process almost all products. Small and medium he does cleanly, and for large and very large he performs roughing. For their finishing, I have two more standard sizes, which are quite enough for the entire range of manufactured products.
Cooper one-hand clasps
Brackets are used for the same purpose as semicircular brackets, with the only difference that they are intended for products of the smallest sizes. Accordingly, the smaller your products, the smaller the radius and width of the staple should be.
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Everything that has been said about semicircular staples is also true for staples. Sketch # 4 shows that the edges of the bracket below the horizontal centerline are rounded inward. The intersection points of the horizontal centerline and the scraper blade are the mating points of two different radii. How much to make the second radius smaller - see for yourself, it depends on the size of your products.
A little exotic
In the process of mastering the craft, each master from time to time has various problems, for the solution of which it will be necessary to invent a special tool or device. There are, in addition to the main ones, a great variety of different highly specific cooper scrapers. As an example, consider a unique tool invented and made by one of my acquaintances, a master.
This staple does not have a single surface that could be called a base. The handles diverge in different directions, moreover, in planes almost perpendicular to each other. The canvas has a smoothly changing radius of curvature, and even just as smoothly wrapped with "Mobius". None of my acquaintances would undertake to draw this scraper, but even if they did, hardly anyone would be able to read the drawing. So here I am just showing appearance in various angles.
Life does not stand still, it moves. Something dies off in it, making room for the new, but something remains unshakable, like fashion - everything is new, it is well forgotten old. About the scraper and its modern application my story.
I was prompted to master this tool by a case when a friend presented me with several bags of shed rubbish left over from a father-in-law, a well-known artisan in our district. Stunned with luck, I took out from my bags either a rare selector, or a set of cripples - a true gift of fate, and even a surprise - a curved forged knife, shaped like a sickle, with two vertical handles. This outlandish tool turned out to be a scraper, which I saw many times in the pictures, but did not have to hold it in my hands. Immediately, intuitively taking it in my hands, I tested it on a log and realized that I wanted to master the work with it.
It turned out that the scraper is much older than I could have imagined. Already in the Middle Paleolithic, people used a stone scraper, flint blades with an inwardly beveled arcuate working edge. With the advent of iron in everyday life, the scraper takes on a familiar form for us and no longer changes. He served for stripping, scraping the bark. It is the peeling, not the shearing off, of the material that has determined such a long life for this instrument. Let's recall the structure of a tree: bark, cambium, bast, sapwood, core and heartwood. The cambium layer and the bast part of the wood are the natural protection of the wood from external influences. It is the preservation, not the cutting of the bast, that is the main task of the scraper. Prying off the bark and peeling it off, the scraper crushes the back surface, smoothes the bast to a characteristic shine, compacting and leaving the wood intact. The movement of the scraper is possible only along the cambium, since it is soft and loose in structure, and it is completely unacceptable for the instrument to get stuck or split the wood. The movement of the scraper is directed towards itself, by the effort of two hands, smoothly and without jerks, in order to tear off rather than cut the material and, of course, along the growth of the fibers, from the butt to the top. After scraping with a scraper, the surface of the wood takes on a characteristic, waxy white color... The wood starts to shine, as after waxing or varnishing. If such a visual effect is observed, then technological process performed correctly. The walls of a log house made of logs "treated for a scraper" usually no longer need additional protection and attract attention with their unique and natural beauty.
But it is possible to carry out a rough, as is written in the majority of literature, primitive planing with a scraper. Don't know why primitive? Having slightly sharpened the cutting edge, it is very convenient for me to trim, clean and adjust the thermal groove with a scraper when knitting a log house. Yes, I clean the corner bowls and adjust them. But this is an exception rather than a recommended practice. Since the proverb is still alive: “after supper mustard, that after the scraper - an ax.
In the recent past, debarking logs under the scraper was widespread, since people tried to use natural protection as much as possible, without having invented impregnation yet and performing many operations by hand. Today, many firms also offer their customers a "scraping" log, but in practice they remove the layer by planing, rather than crushing the bark with scrapers until it shines bast. Such a log is sold, of course, more expensive, and if you agreed to pay for this work, try to control it.
tool steel 9ХС and hardened up to 55 ... 58 HRC. Blade bending radius - 200mm, sharpening - straight chamfer down. Handles 140mm long are made of beech wood and impregnated with oil. Cutting length - 170mm or 270mm, width 36mm
To select the desired staple, click on the product name
from 3600 p
Staple PETROGRAD N3, 170mm (semicircular, R60)
A semicircular staple with upward curved handles will be convenient for various operations in carpentry: precise adjustment of logs to size, quick removal of material, as well as selection of recesses. The blade is hand forged from tool steel 9XC and hardened up to 55 ... 58 HRC. Blade bending radius - 60mm, sharpening - lenticular ... Handles 140mm long are made of beech wood and impregnated with oil. Cutting length - 170mm, width 36mm... Blade thickness - 6mm, sharpening angle - 30 degrees. Manufactured in Petrograd (Russia).
3500 p
Staple PETROGRAD N5, 270mm (Swedish type)
Forged bracket curved in two directions has the advantagebefore other non-linear braces, in convenience and control. The blade is hand forged from tool steel U8A and hardened up to 55 ... 58 HRC. Handles 140mm long are made of beech wood and impregnated with oil. Cutting length - 270mm, width 36mm... Blade thickness - 6mm, sharpening angle - 30 degrees. Total length of the scraper is 650 mm. Manufactured in Petrograd (Russia).
5200 p
Staple PETROGRAD N7, for cleaning grooves in logs (Meddragskniv)
Staple PETROGRAD N7, for cleaning grooves in logs (Meddragskniv). Complete analogue of the Norwegian Meddragskniv scrapers. The thickness of the blade is 6 mm, the radius of the selected groove is 35 mm, the distance between the handles is 400 mm, the sharpening angle is 30 degrees. Forged hardened blade made of 65G steel, cutting edge hardness - 55-58 HRC. The total weight is ~ 1.1kg. Handle length - 140mm. The handles are made of beech.
Designed for finishing the lunar groove after tesla (removes the effect of flaking). The shape of the scraper arms allows it to be rotated during operation to sand the entire groove surface. Forged by hand.
Production - factory of joinery and carpentry tools PETROGRAD.
Made in Russia.
8400 p
John, the author of the YouTube channel "John Heisz - I Build It", tells about the making of another tool - the scraper, which, although not very often used in carpentry, but, nevertheless, it is simply necessary. In addition, he will tell you about a very reliable way to attach the tool handles.
Materials.
- Hardwood
- Old diamond disc for concrete
- Two-component epoxy resin
- Sandpaper
- Impregnation for wood
- Thick copper wire.
Manufacturing process.
It is quite simple to make a scraper from an old, unnecessary diamond disc for concrete, which the master demonstrates to us.
In his own words, he sketches the shape of the future scraper from memory, recalling the shape of similar products in the photo on the Internet, while trying to fit as much as possible into the size of the disc.
And he starts marking at the front edge of the knife, its tip, which will be about 5 inches long. This is a lot for a small scraper.
John then cuts off a small piece of steel with a cut-off wheel to see if it can be hardened. It is a good quality steel and will give a good pull. The author had problems with the first cutting blade: it got stuck in the cut and overheated the metal. John replaced it with a newer one and it worked much better. The fact is that the steel of most of these discs is already hardened, and it would be very difficult, if not impossible, to cut with such a tool. Of course, this is not a problem for a plasma cutter! However, in this case, it will take a lot of time to sew to a given shape.
The master uses an ordinary grinder here, although there is also a rechargeable one in his arsenal. The thing is that the cordless machine is good in those cases when you need to make a quick cut or in such works where you do not need to apply a lot of effort. Otherwise, it is better to resort to a conventional corded tool. Its discs last longer and cut faster at higher rpms.
After cutting out the main part, he slightly modifies difficult places with a sharpening disk. For this kind of work, it is better to have a spare sander with a regular sander to quickly switch from one to the other.
Marked the future blade and fixed the workpiece with a clamp.
Then he cuts at right angles, and cuts the edges of the future handles, the purpose of which will be announced a little later.
Initially, the author intended to carry out all the work on sharpening the blade with the help of a hand grinding stone. But, since in his arsenal there was a tape grinding machine, the master did not refuse his services.
In front of you homemade machine Roger with 2x72 '' tape. All the plans needed to build it are available at this link.
To guide the blade at the correct angle and keep it, John secured a piece of board to the machine.
The next step could have been omitted, since the author mentioned that this is already hardened steel. In addition, he did nothing that would contribute to overheating. He heated the blade to a slightly crimson color, just cooled it in water.
John tried not to overdo it with cleaning and limited himself to removing rust and scale formed after heating the steel. But if you wish, you can bring the product to shine.
Next, the author cuts out a piece of maple for the handles. And then the craftsman finds interesting solutionhow to attach them to the blade. It makes slots wide enough for the shank to fit, right on circular saw... It is much faster and easier than drilling these grooves.
And then he will fill the open part of the groove with a board of the same thickness.
And now the reason why John cut these slots at the ends of the shank ... The most unexpected and dangerous thing that can happen while using the shank is when the handle suddenly slips off the shank. To prevent such a development of events, the author bends the ends of the shank with pliers, in this way, after warming them up properly.
And then immediately puts the handle on them. Thus, he burned the grooves in the handle for the "mustache". Charming technical solution, is not it?
Repeat the same action with the second handle.
Having liberally coated the grooves with epoxy, installs the handles on the shanks, and drives a suitable board into the groove.
After polymerization epoxy resin, cuts off excess planks and grinds them thoroughly with sandpaper.
Initially, the master planned to use a copper tube for the safety ring, but later decided to use copper wire, twisting it several times around the handle. This is an ordinary copper wire from a power cable that has been previously stripped of the insulation.
This turned out to be quite difficult. This work should have been done before the handle was placed on the shank. Then the wire could be bent more precisely in shape.
John then coats the copper coil with a thick layer of epoxy to hold it in place. At the end, the author overlays a couple of layers linseed oil on the handle, more for beauty than functionality.
A day for drying and finishing.
Of course, the obligatory impregnation with linseed oil.
First approbation on a piece of soft wood. Excellent cuts!
This is the kind of tool John made.
Thanks John for detailed master class, and especially for a reliable way of attaching handles!
A staple (plow, nastrug, coroder) is an old carpenter's tool in the form of a straight or curved knife with handles at the ends, designed for stripping bark from logs and their primary shaving, as well as the main tool for manual planing riveting in the manufacture of cooper dishes (tub, cad etc.).
Skobel (another name - plow ) is used for strippinglogs for felling ; after stripping, the wood becomes light, without traces of bark. The walls of the log house, processed "under the scraper", do not require additional sheathing and finishing and attract the natural beauty of the tree. At the same time, it is impossible to level the surface of the log with a scraper - irregularities remain, repeating the shape of the trunk, and scuffs from the ax on the knots.
In general, the scraper is a universal tool. Once upon a time in Russia they were used instead of planes. One and the same scraper can both "drive the chips" from the workpiece, and remove the transparent thinnest chips from it. But for different purposes, different brackets were made. So, for example, a straight scraper, with which carpenters hew and scrape logs, is completely unsuitable for coopers. It's all about two important parameters that determine the functionality of the staple. This is the angle between the plane of the blade and the plane of the handles, as well as the angle between the handles themselves.
Straight cooper scraper
A straight cooper's staple is usually used to plan the outer face of a rivet on a cooper's bench. It can also be used to chamfer the bottom or the end of the product. In accordance with the type of work, straight staples can have different blade lengths.
