Question about curved scrapers

[DaveP (UK)]

Especially smallish ones, such as you might use when inletting a round barrel,
Are they best used with a sharp square edge or with a burr formed in the usual way?
I'm having trouble visualising how a burr edge could be used unless the scraper were to have such a small radius, compared to the channel, that I might as well stick to paring with a gouge.

[Darrin McDonal]

Hi Dave,
You can use scrapers with or without the burr and as for me all of my hand scrapers get a burr around all the edges. My barrel channel scrapers do not because they get a much more aggressive work out and a burr wouldnt hold up to it. My bbl channel scrapers are either bent & shaped old files or the Brownells BBL channel scrapers ( in addition to my barrel channel planes) which are nothing more than a series of washers with nice square edges and a stout rubber washer in between each cutting washer. They do work good but are a little tedious to resharpen.   
Darrin

[DaveP (UK)]

Thanks for the ideas!
 I hadn't got quite that far, mentally, mainly because I've just started my first pistol using, so far, tools I already possess. I had been thinking of cutting up some old cabinet scrapers but recycling some old files sounds better.
What sort of edge profile should I try for? Working edge a sharp right angle I imagine, but should I relieve the trailing edge, and if so, how much flat should  leave behind the working edge?
Or perhaps it should be more like a wood turners scraper?

[Acer Saccharum]

Long John makes his own scrapers. They look like a chisel, except a pretty decent hook on the end where the scraper is. The end is bent down, and sharpened. Cuts on the pull stroke.

The bed gives the handle some lift, so your knuckles clear the barrel channel edges.

[eddillon]

I have used various sizes of these for 35 years.

http://www.gunline.com/inletting.html

For octagon I use Jerry Fisher scrapers that I grind the edge to the proper angle.

BBoth of these are available from Brownells.

[Mark Elliott]

I now sharpen and hone all my scrapers square, no burr.   My finest and most used scraper is a utility knife blade honed flat on the edge.  I got this idea from Allen Martin.   I regularly hone it on a 1200 grit diamond hone.   The edge is very sharp and will remove a lot of material.   You don't need a burr to cut, just a well honed edge. 

[Flint62Smoothie]

FWIW I reamed out some washers, stacked them into a bolt at a tight fit (bolt OD to washer ID), then turned them to a common OD on the lathe, then disassembled them, put them onto a holder w/ a fiber washer (smaller OD) between them ... and it cuts great!

I just need to fab a 2-handed tool ...

[Darrin McDonal]

That washer method is great. Most of our hand tools are usually easy enough to make ourselves and end up with a tool that are at least as good if not better than the commercial ones. But time is an issue sometimes.

[DaveP (UK)]

I think a repurposed file will satisfy my present needs, and I think I understand how to go about it - Thanks!

The multiple washer type of scraper is quite interesting. Does anyone know if they are a traditional gunsmiths tool or a relatively modern development?
The reason I ask is that medieval bowyers are believed to have used a multi blade scraper to finish longbow staves - nothing new under the sun they say...

[Dphariss]

Especially smallish ones, such as you might use when inletting a round barrel,
Are they best used with a sharp square edge or with a burr formed in the usual way?
I'm having trouble visualising how a burr edge could be used unless the scraper were to have such a small radius, compared to the channel, that I might as well stick to paring with a gouge.

A burred scraper has to be soft enough the roll a burr. Hard scrapers don't burr well and will need to be sharpened to a square edge. So I burr my softer ones and the hard ones are square. The square edge is often the most useful for flat scrapers burred is better for contoured scrapers. Barrel inletting scrapers that one buys are hard with a square edge.

Dan

[Long John]

Yea, I was just quietly lurking for a while and then Acer blew my cover!

Here is a small sampling of the pull scrapers I make.



I make them out of 1095 spring stock that I pick up at Dixon's Store.  I cut and file to shape, bent to about a 75 degree angle and then sharpen with the bevel on the outside of the edge making sure that both sides of the cutting edge are flat and smooth.  I then heat to bright red, quench in light oil, polish so I can see the colors and then anneal to an amber color before quenching again.  I then polish the edge on my diamond stones.

They cut on the pull stroke.  When the edge begins to hesitate cutting I polish the bevel edge ONLY pulling the edge across the polishing leather so that the cutting edge is trailing.  This makes a microbur on the edge that cuts like crazy.

Acer an I talked about doing a demo on how to make them at the next Fair.

Best Regards,

JMC

[smokinbuck]

JMC,
Your scrapers intique me. Do you make them for octagon as well as round barrel channels anddo you sell them?
Mark

[Long John]

Mark,

Your answers: yes and no.

I make scrapers for octagon barrel channels.  Mine are sharpened only on the bottom flat edge.  To work down an obliques flat I just rotate the scraper.  This helps avoid widening the barrel channel by acident and getting a sloppy fit.

I am a hobby gunmaker - I do this for fun.  But I am thinking about doing a demo at the Fair next sumer on making scrapers.  Once you learn how to make your own it sets you free to make the tools you need, as you need them.  No one knows better what you need than you!

Best Regards,

JMC

[T*O*F]

Brownells offers these, both in round and flat configs.  I've had the complete set for more than 20 years.  Personally, I use them more for edging and flattening lock, sideplate, and trigger/guard inlets than for doing barrel channels.

http://www.brownells.com/gunsmith-tools-supplies/stock-work-finishing/stock-making-hand-tools/wood-scrapers/hard-fit-curl-scrapers-prod398.aspx

I also have a set of these and find them more useful than the scrapers above when inletting "round" barrels and cleaning up ramrod channels.

http://www.leevalley.com/US/wood/page.aspx?p=67392&cat=1,310,41069

Some guys enjoy @$#%&*@ around making their own tools and more power to them.  It's just not my thing as it wastes too much time.  Would rather have a tool handy than get diverted in the middle of a job.

[smokinbuck]

John,
Thanks for the input, makes sense, re opening up a channel by mistake. Guess the best way is still the old way, no shortcuts.
Mark