Plane Floats

[Leigh Betsch]

I bought a old Sheldon metal shaper and spent the last month tearing it apart and cleaning it up. I have tinkered around cutting teeth for an edge float and cheek float. My question is, Is there an optimal pitch for float teeth? Do all floats have the same pitch, edge, bed, cheek? From what I can glean from the Lie Nielson site it looks like at least some of them are 8tpi. How about thickness is 1/4" too thick? I've cut teeth on a 1/8" and 3/16 O1 stock but I have 1/4" in more usable widths that the thinner stuff.

[Kent A Bathurst]

Leigh - dunno about their smaller plane floats, but.....

The LN mortise float is 7/64" thick with teeth @ 1/32" depth; their cheek float is 3/16" thick also with teeth depth @ 1/32' [I don't have a decimal caliper, just a Starrett dial fractional].

8 tpi on both.

Hope this helps. If you need other measurements, lemme know.

Say "Hi" to my Matsumuras....:D :D...Ooops - your Matsus

[David Weaver]

Leigh - for plane floats 1/8th and 3/16th are where you want to be. Probably most of them came out of 1/8th stock, except the thick bed float and the thick edge float (which i think are both 3/16ths). You could make a very stiff bed float with 1/4th, but I with the others, you need the cheek and side floats to be thin for room to work and flex in the side floats is helpful.

No rake on the teeth (except the first tooth can be more aggressive than zero rake so you can dig in with it). That's important. If you put rake on them and make them less aggressive, they won't work well at all - too much tooth surface on the material.

[Andrae Covington]

Leigh - for plane floats 1/8th and 3/16th are where you want to be. Probably most of them came out of 1/8th stock, except the thick bed float and the thick edge float (which i think are both 3/16ths). You could make a very stiff bed float with 1/4th, but I with the others, you need the cheek and side floats to be thin for room to work and flex in the side floats is helpful.

No rake on the teeth (except the first tooth can be more aggressive than zero rake so you can dig in with it). That's important. If you put rake on them and make them less aggressive, they won't work well at all - too much tooth surface on the material.

Actually the ones from LN have 80° rake; they are fairly shallow teeth. I don't know their reasons, but if one were making these things with a triangular file, tilting the file 10° would mean removing less metal. If my calculations are correct (based on 8tpi in 1/8" steel), it would mean removing 0.0003798 cubic inch per tooth vs 0.0005638 cubic inch per tooth. ...hey, just sayin' :D:eek::rolleyes: Of course with a powered shaper, cutting deeper teeth would be no big deal. But you still have to sharpen them with a file. Perhaps it is to reduce warpage during the heat treating process.

[David Weaver]

I just pulled one of mine out and took a look, it's hard to tell looking at it, but you're likely right about the 80 degrees (as in more aggressive than zero rake since people see rake differently depending on what they call positive or negative). I think i've relaxed it a little on mine just by sharpening, and they're probably close to 90 degrees. At 80 degrees, they're definitely easier to sharpen up to the business ends than they would be if they were 90.

[Leigh Betsch]

Thanks guys. My first trials are neutral rake although I was thinking 10 positive rake might be good to cut a little more aggressively. I took a stab at .150 pitch on the edge float and .100 on the cheek float. I don't really know how deep the teeth are as I just cut them until the tooth cleaned up, like you'd do if you were sharpening them. I'll keep the 60 angle so they can be sharpened with a saw file. Depending on what pitch I use the tooth depth will pretty much work it self out t compensate for the tooth spacing. Sounds like I should cut down some 1/4 stock to 1/8 or 3/16. I hope to get back to this tonight but today is spring motor maintenance day. Lawn mower, motorcycle, tractor, transfer pump, generator, .... my piston count has gotten out of control.

[Trevor Walsh]

When I made mine by hand I used 0 rake, and it cuts great. Leigh, are you going to be manufacturing these? and if you're using 1095, 01 or W2 I'd be tempted to say leave them unhardened. Reasons being; no HT warping to attend to (or loose stock on), easier to sharpen, and shorter lead times/less cost. considering their use they don't dull to quickly anyways, I'd say hardened and tempered floats would be for a production wooden plane maker like Bickford, or C&W.

[greg Forster]

most of the antique floats I've seen have a forward rake of 8-10 degrees; in addition they have a TPI of 5-1/2 to 7. I read somewhere one of the reasons LN went with 8 TPI is it's
more easily re-sharpened than a coarser tooth pattern (the file is "jigged" better)

as you increase the forward rake of a tooth, the gullet becomes deeper (see drwg) This can become an issue with a coarser tooth pattern. I learned this the hard way; when filing a side float (1/8" thick) @ 8 degrees/6-1/2 TPI, I lost my concentration on a few teeth and ended up with more like 10 degrees and 6TPI. This has left so little steel that eventually the float will break here.

As David said , there is an advantage to having some flex, esp. in the side floats;
Larry Williams mentions this also.

I did not temper my O-1 floats; that's a learning curve down the road a bit

193929

[Leigh Betsch]

Trevor, I hadn't planned to manufuacture these but once I figure out what I like it would be pretty easy to make a few extras while I'm set up if anyone is interested. I agree that non-heat treated would be a lot easier and perhaps even better. Mostly because of no warping they can be cut to size right off and ony slight filing to sharpen them.

[Trevor Walsh]

Glad to hear it. I only asked because given the shaper setup, it would be pie to run off a few of your given pitch and rake.