Pull-Push Scraper

Some while back a post was made on the Forum concerning the use of scrapers. Posing the question as to whether they should be pushed or pulled. While I had seen references to pull scraping for recessed surfaces, it was not something I had given much thought too.

The Forum post did however start me thinking and a Google search brought up some very good information and several posts over the years on Forums in the USA. I tried the pull scraping technique by modifying a small Eclipse flat scraper that I had. Although I have done a great deal of conventional scraping in the past, I did find the pull scraper easier to use and more controllable. Also with my muscle problems this method did not give me so much grief.

During my searches one design in particular by "Agathon" took my interest and started me off on a design for myself. The above scraper has interchangeable blades of HSS or Carbide. The end faces of which are ground and honed dead square. The resultant face can be at 90 degrees to the blade or at an oblique angle. This allows the blade to access the corners when doing dovetail slideways.

The head that carries the blade can pivot to 5 different positions and in the in-line position the scraper can be used as per a conventional push scraper, with the appropriate blade.

The position of the handles are adjustable to suit each individual user. They are made from one Woodturning Chisel handle. An M5 Wood Screwcert allows an M5 grub screw to lock the handles in the desired position.

Some results from this type of scraping can be seen on the work tables in my post, HSS/TUNGSTEN TOOL HONING MACHINE.

Regards

Gray,

Gray

How are the blades held in place and how do HSS blades compare to carbide?

If you left click on the last image you will just make out the M6 Grub screw which presses on an inclined Brass pad. This gives a wedging action to clamp the blades and any pressure along the blades from the cutting action adds to the gripping action.

The Carbide blades are ex-industrial wood planer. I use these mainly to rough out, as the edge last for some time between sharpening. The finish left by the Carbide is not so good as the HSS. Due mainly to better honing facilities for HSS.

The HSS does however last for a very long time. I would have to hone my Carbon steel Eclipse tools almost constantly to get similar results. For my part I consider the HSS to be the best all round material.

Regards

Gray,

I like it. Nice work.

Steve.

Thanks for the kind words Steve,

The following 3D view courtesy of John Slater, will probably shed more light on the workings. The Brass locking pad is not shown, as at the time John received my drawings I had not drawn this detail up.

Hope this answers any construction queries,

Regards

Gray,

That's a nice looking design Graham.

Is there any amount of spring in the scraper or is it fairly rigid?

Pete.

Hi Pete,

Thanks for your kind comments,

The blade is 10 x 2 mm section and protrudes from the head about 15 mm. In use the pressure required to remove material is not that great, despite the cutting edge being a square corner. I hold the lower handle in my Rt Hand, similar to how I would hold a pen when writing. The upper handle rests on my Rt collar bone area.

Using the index finger of my Lt hand to align the blade on the work before pulling with my Rt hand. I have not noticed any spring in the blade in use.

Regards

Gray,

That's really good, if you have any other pictures of it disassembled I'd love to see more of that, seeing the technique of using would be interesting too.

Hi Pete,

I only managed to get some photo's of the tool fully assembled on the one bright day we have had recently. I like to use natural light when ever I can and the current weather is abysmal for photo-shoots. Plus I have not considered writing this up as yet, other projects need sorting first, so the need for photos of the parts was no a priority.

If you do a Google for pull-scrapers, on the Forums in the USA there are some interesting videos of using the Pull scraper. Also the Swiss have a different way of going about scraping. They go in 4 different directions. Using this technique I have found it quicker to bring a surface to flatness.

One video on hand finishing precision squares I found interesting. Perhaps one of the Moderators can paste the links here?

Regards

Gray,