I have several older (not antique) planes that I should flatten the bottom (soles?).
How do 1.5"-2" thick granite cut-offs compared to float glass for this purpose?
I have several older (not antique) planes that I should flatten the bottom (soles?).
How do 1.5"-2" thick granite cut-offs compared to float glass for this purpose?
depends on how flat the granite is. If it's flat and nice and long then go with it. Float glass can be shimmed a little. Float glass on top of a granite cut off with some sheets of paper under to shim things to flat makes for a nice cheap and useful flattening substrate. For smaller planes, blades etc, (anything that finger pressure can easily lap a bow, convexity into you can shim the glass so it is convex just a touch. Helps with those small items.
"A pessimist sees the difficulty in every opportunity; an optimist sees the opportunity in every difficulty."
- Sir Winston Churchill (1874-1965)
Float glass can flex if it's used on a surface that's not flat. I use the top of my table saw and sandpaper for this purpose.
Sharp solves all manner of problems.
I use a 36" threshold from Home Depot for my planes. I don't use it to flatten them but to sand and shine them up
As sure as the Sun rises in the East Ralph's planes are shiney. He knows of what he speaks. BTW, if you would like to see some great plane restorations check out Ralph's blog https://accidentalwoodworker.blogspot.com
ken
Last edited by ken hatch; 01-01-2019 at 7:39 AM.
Both granite and float glass can bend a little. The thicker either is, the less that it bends.
With granite, be sure that the back is as flat as the face. If it's not flat you can use thinset or leveling compound to support it from bending or better, move on to another piece. In years past, granite was cut with wire saws and the thickness was very inconsistent. In the last few decades, they have moved on to diamond gang saws that produce a much more consistent thickness. It's not perfect, but, it's much better.
Your 1 1/2" thick pieces should be great for flattening your planes. I use a 12" x 24" x 3 cm piece of granite for flattening. I'm in the business, so I was able to select a piece that's consistently flat on both faces. Fortunately this was easy.
Be sure to fully support your granite. While it seems stable as a rock (sorry for the pun), it can flex a little if not fully supported.
Allen
I'd be willing to bet more people knock their planes out of flat than ever make them better. It is too easy to be inaccurate. Leave them be unless you're 100% sure that they can not work as is.
Bob,
I couldn't agree more. If you are sure the sole needs work your best bet is one of two things: Sell the plane to someone (not a friend ), or send it to a machine shop. Another option is to turn it into a roughing plane, scrub or jack. BTW, you should see the sole of my 30 year old wood stock scrub plane, ain't no way no how a metal plane sole could be a bad and it still works a treat.
ken
A milling machine and fly cutter
check to see if they’re flat before you work on them. How far out and where they are out matters. A touch up at the ends isn’t noticeable and I could live with the center slightly up on a long plane.
Bumbling forward into the unknown.