SLT BF is shorthand for 'Select Broadfork'. Mike the Handleman packages these beautiful handles and ships them to me a hundred pairs at a time. Select grade wood handles are the best that money can buy. In select grain wood, the grain is straight for the entire 4 feet of length with no runouts. What that means is that I get only about 8 handles for every 100 he makes. When he told me that it was going to be expensive to buy the select grade wood, I told him that I don't care what it costs, I just want the best. This is an heirloom tool.
This is a bird's eye view of a box of handles showing the end grain of the wood. I don't randomly ship the handles as they come out of the box. I set the bar high and I go to the trouble of finding matched pairs of handles to go on your broadfork.
Look at the growth rings on these two handles. The ones on the left are fine grained and tight; on the right, much farther apart.
This is an even more radical difference. The wide grain handles have a bit stiffer feel and the tighter grain gives a more supple touch, a bit more dynamic feel. To make a broadfork with these two handles would mean that one would feel quite a bit different from the other in use.
After matching and sizing the handles to whisper perfectly into the handle sockets, the bottom end is soaked for a couple of days in a 50/50 mixture of boiled linseed oil and turpentine. The wood actually drinks this mixture about a foot up the handle, gets saturated and it starts seeping out. The result is that it stabilizes the wood and helps to prevent the wood from checking (cracking) and dry rotting over many years of use.
You won't find varnish on these handles, they're just finished with the same mixture. Varnish seals the wood with and can cause sensitive hands to get friction blisters more easily as sweat is trapped between skin and varnish. I learned that fact many years ago as a beginning blacksmith. The result is a tool that is treated much the same way as it would have been a hundred years ago using distilled pine tree sap (turpentine) and linseed oil, which is pressed from flax seed. If you read your Foxfire Books, you'll find that both linseed oil and turpentine have been used for centuries in folk medicine.
The same mix is used on the metal part of the broadfork because I don't think it's a good idea to be painting a tool you're going to shove into your nice organic soil. The paint wears off immediately and gets into the soil where your plant roots pull out their nutrients.
It's important to me to think about these details to provide you with a tool that is as good as it can be. I make every one of these myself; no one else touches them before they arrive at your garden. Quality is the name of the game here at Gulland Forge.
Good soil to you.