Hello all,
I don't post here too often because I don't have much to add, but I do read most of the post on this forum.
I am working on my set of journeyman knives for the atlanta blade show and I have run into a bit of a problem.
For one of the knives I have a sculptured guard with some complex curves, I really like the shape and how it feels. I wanted to give this part a very clean satin finish but i find it impossible to make it on a three dimensional part like this, I cannot get the scratches in the same direction.
I have a pretty decent mirror finish on it right now, because this is the only way I can get it looking even, but this is not really what I wanted and I worry that it would not be desired for a journeyman test knife.
Maybe someone more experienced knows of a nice way to finish these sculpted parts evenly.
I've seen people do hot blueing and sandblasting, but both are beyond my shop capability right now.
No doubt the problem rests in that concave perimeter around the back, as this is a tougher spot. I would approach it one of two ways. Either a lighter backed abrasive, like paper that easily flexes into that area with the side of your thumb, or 0000 steel wool which gives a softer satin but very easily negotiates the curves but can be more difficult in getting all lines parallel.
The problem is in that curved back as it is a continuos surface around the entire perimiter. That leaves you no way to keep the satin "scratches" continuos around the whole surface. There will always be a spot where you have to stop, and start again.
You could try the abrasives Kevin menthioned and see if that works for you. It would take something extremely fine to not have a stop/start effect. You could also sand from back to front rather than around the perimeter. That may get you the look/consistancy you want. Probably far easier to make the satin even when going across that surface rather than around it.
I have found that for sanding these curvy features the answer is found at ........the drug store in the stationary section. Rubber erasers come in a variety of colors and hardnesses. They all will conform to a curved surface to some degree.
“So I'm lightin' out for the territory, ahead of the scared and the weak and the mean spirited, because Aunt Sally is fixin’ to adopt me and civilize me, and I can't stand it. I've been there before.”
Thank you both for the replies.
I will try the steel wool, I have some of the very fine stuff in my wood finishing toolbox.
I will also have a look for an eraser, I didn't think of sanding in the opposite direction (from handle to blade), that is why it is great to be able to ask other makers all over the world.
The stop/start lines were exactly my problem, even with very fine 2000 grit they were still visible in good light.
You might be amazed at what you can accomplish with these. They are a hard rubber that is impregnated all the way through with abrasive. Being somewhat flexible might be what you need.
Just a heads up about those Sandaflex blocks.... you can purchase them individually at TruGrit Abrasives.
I've been using these blocks for years in my shop, and I recommend them to my students, especially if they are trying to get a nice satin finish on JS test/presentation blades.... they do not leave "fish hooks" like sandpaper does (hint, hint) 😊
You can cut these blocks on a bandsaw or with a hand saw into any size you like, and I often shape them on the grinder to fit specific applications.
Also, don't overlook scothbrite hand pads.
I have several "blocks" that I made from rubber horse stall matting, with "hook" side velcro glued on.... and thes hand pads stick to it as if they were the "loop" side of the velcro.... just another option to make your finishing life easier. 😉
Ed Caffrey, ABS MS
"The Montana Bladesmith"
www.CaffreyKnives.net
Thanks again,
Who knew that there was so much variety of abrasives, I already have an entire cabinet full and still feel like i just barely scratched the surface. (theres a pun in there somewhere 😉
I already love the scotchbrite pads use them all the time for final finishing.
Great question and feedback. I've been using Sandaflex blocks and really like them, but will be adding a few of these suggestions to the mix. Thank you!
