Thread: Disston D-8 replica

Disston tended to use a smaller first bolt ... I always wondered why ... probably exactly this, I guess.


What about ... (I know your handle is inset, but ...)




Hard to judge from close-up pictures IMHO ...

Hi Rob. 3 saw bolt assemblies looks the go. I doubt the 4th assembly would be able to pick up any of the saw plate. Not sure about the look of the bottom rail to cheek connection. The additional complexity of taper grinding the saw plate would scare off most other saw makers. You deserve a lot of kudos.

Look forward to viewing the completed hand saw.

regards Stewie;

I worked more on this saw today between other tasks adjusting the hang angle and blade inletting. Here is a comparison of old and new.

3 mediums and a medallion.jpg

I like the medallion in the middle and three medium head screws. Abdul is less than interested.

Abdul cant take it anymore.jpg

Now for the stamp for the medallion. I talked with my jeweler friend today and he said he would press the vendor to finish my quotation.

Stewie, did you receive yours yet?

Hi Rob. Not yet. I delayed the order with the stamp until I got around to purchasing a 10 tonne hydraulic press. The press arrived yesterday, so I have set it ready for use when I get the time.

Stewie;

Somehow I managed to squeeze in some work on this saw today - this is turning out to be an extremely busy spring for me.

First the configuration of the screws. I settled on the distribution pattern of the D-8 discussed above and the question now is which size.

Medium

screw positions final.jpg

or large?

screw positions large final.jpg


I decided to go with the large ones because the topmost screw looked a little lost in that relatively broad area of the handle. I set this handle up with the stainless bushings to ensure a positive and durable lock-up between the stock and the blade.

stainless bushings in place.jpg


A few minutes later and we have the screws in.

D-8 handle finished a little closer.jpg


D-8 full length.jpg

Now for detailing and finish application.

When I get my saws to this stage I start testing them. I sharpened and set this saw and gave it a try. It took some adjusting to get the set correct so that it tracked straight. While making test cuts I noticed that this saw did not have the harmonic oscillation that causes the tip of the blade to ring that so many Disston saws have. Does anybody know if this tip-ringing phenomenon has a name? I've always found the ringing of some Disstons to be extremely annoying in use. The Disston is sharpened and pitched to the same specification as my D-8. (15^o -> 10^o progressive rake, 15^o fleam, 5^o bevel and 12 tpi)

This one works better overall in my hand and it cuts about 20% faster than does the Disston.

I also pulled the blade around 180^o (bent it in a U shape back toward the handle) and let it snap back - no residual distortion in either direction.

Originally Posted by rob streeper

While making test cuts I noticed that this saw did not have the harmonic oscillation that causes the tip of the blade to ring that so many Disston saws have. Does anybody know if this tip-ringing phenomenon has a name? I've always found the ringing of some Disstons to be extremely annoying in use. The Disston is sharpened and pitched to the same specification as my D-8. (15^o -> 10^o progressive rake, 15^o fleam, 5^o bevel and 12 tpi)

I have a few ideas. Is the tip of the Disston any thinner than yours? Some of them get very thin right at the toe-top.

I've found that the "inefficient" sounds vary with how I hold my hand and arm.
My hand can be rotated a little CW or CCW out of vertical ... and sometimes the direction I'm holding is not directly along the line of the saw ... so tiny adjustments make a difference to the sound and any"flapping".

So ... I wonder, even if the blades were identical in thickness profile if, being newer, yours has more stiffness/less flexibility or "flop" to it?

I wonder if there can be changes along the "grain" of the metal with time and use?
Or if it is directly related to the "grain" of the metal.

Cheers,
Paul

Here's some photo's of the bend test.

first to the right.jpg


then to the left.jpg


still straight.jpg

Originally Posted by pmcgee

I have a few ideas. Is the tip of the Disston any thinner than yours? Some of them get very thin right at the toe-top.

I've found that the "inefficient" sounds vary with how I hold my hand and arm.
My hand can be rotated a little CW or CCW out of vertical ... and sometimes the direction I'm holding is not directly along the line of the saw ... so tiny adjustments make a difference to the sound and any"flapping".

So ... I wonder, even if the blades were identical in thickness profile if, being newer, yours has more stiffness/less flexibility or "flop" to it?

I wonder if there can be changes along the "grain" of the metal with time and use?
Or if it is directly related to the "grain" of the metal.

Cheers,
Paul

Hi Paul,

The grind profile of the D-8 is very similar to my saw. I'm wondering if the early references to 'fast and loose' in the literature discussing hammer tensioning are in fact discussing this effect.

Cheers,
Rob

hi Rob. That last photo that shows the line of the saw plate after its been flexed in both directions. Does that concern you.

regards Stewie;

Originally Posted by planemaker

hi Rob. That last photo that shows the line of the saw plate after its been flexed in both directions. Does that concern you.

regards Stewie;

Hard to take a good photo with the iPhone. Looking at the saw in person I can see the blade is straight. I'll try to get a better photo, the skew back accentuates the appearance of non-linearity if the centroid of the focal area is less than perfectly aligned with the long axis of the blade. Here, this is somewhat better.

straight.jpg

Thanks Rob. That looks much better.

Stewie;

I've been experimenting with hot finishes too. Here's the handle after three coats. This is shellac/beeswax/BLO.

3 coats hot wax treatment.jpg

A little bit more information pleassseee Sir
(On the hot finishes)

Here's the current recipe:

~100 ml turpentine + ~100 ml BLO + 1 button of shellac + 30 gm beeswax. Mix together in a glass jar, place the jar in a pan of boiling water until wax is dissolved - careful of fire safety of course and don't screw the lid down or the jar might explode. Take the pan containing the water and the bottle of finish to your workstation. Wait until the finish cools enough to be comfortable to handle and wipe on with a rag or paper towel. Allow the finish on the handle to cool and buff with a soft cloth. A couple of coats will generally do. When the finish solution is too cool to use the wax forms a fluffy yellow precipitate - boil in water again to re-use.