On Friday, February 1, 2019 at 1:04:19 AM UTC-5, dpb wrote:
On 1/31/2019 6:32 PM, DerbyDad03 wrote:
On Thursday, January 31, 2019 at 6:58:01 PM UTC-5, dpb wrote:
On 1/31/2019 4:14 PM, DerbyDad03 wrote:
....

If I've missed anything or if you have any other questions about the set-up
or my technique, just let me know.


https://i.imgur.com/fSSwztH.jpg

In bulk, that's a reasonable-looking approach.

What we don't see, however, is the actual setup when trying to do a
planing pass.

Other than me feeding the sled in and retrieving it on the way out, what aren't
you seeing? Should I post a link to a video? ;-)

Something's moving but we've no way to tell what from static picture so
that _might_ be of some help, yes. Of course, from afar, it might not
be, either; no way to predict, really.

Unfortunately, the provisions of my WITSEC arrangement prevent me from
posting pictures or videos of myself online. ;-)



That's the setup. What do you think is missing? Is it just the shims? If you
want me to insert shims and then take the picture again, I can, but I kind of
think that that would be a waste of time. On the twisted boards that I'm
actually trying to flatten, I am shimming the gaps both to eliminate any
rocking and fill them in to prevent flex.

I don't think it would be a waste of time, no. Seeing just how you
shimmed it and what's holding what how could be a klew...then again, as
above, from afar, "maybe not!" but you've not found it so far on your
own, so what can it hurt?

As I'm sure you know, every board has a different twist, warp or bow, so
showing you how I would shim the board in the image might satisfy that
situation, but none other.

In this case, I would clamp the front of the board to the infeed end of
the sled and use increasing thinner shims, starting at the highest point
of the trailing end, filling in all gaps on all sides. The shims would be
held in place with either hot glue or double sided tape. Once shimmed, I
would remove the clamp and check for any rocking, flexing or sliding.

Again, as I'm sure you know, there are many youtube's showing the flattening
process, including the shimming part. I'm doing what they are doing.



You don't give any measurements but if I just guesstimate that the
difference is as much as 1/32" over the last 3-ft of the material then
the angle is 0.05 deg from true straight edge. I don't think there's
any way you can measure anything close to that precision with the angle
gauge you've shown nor can be totally assured you don't have that much
flex in the setup shown in a combination of all the places there's room
for any movement whatsoever.

The board being planed is 70". The sled is 72".

As I mentioned, the gap shown in the image is exaggerated because of other
things I did to it. Even then, the exaggerated gap in the image is less
than 2'.

In practice, after planing the board with the sled, the gap is more like
1/32" over 6, maybe 8". Since I am supporting/lifting the sled on the
outfeed end well before the last foot or so goes under planer, I really
don't think the sled is drooping. If anything, since I'm lifting the sled,
I would expect the trailing end to be thicker, not thinner.

That tells me _something_ pretty major is happening that last foot,
then, and the video _might_ show it. I'm still curious about just what
the real stiffness of the machine itself is...I'll admit I've never used
one of the lunchbox planers "in anger" so I really don't have anything
to compare to but heavy iron but I've looked at various models in the
stores and they just look too flimsy for real work to me. I'm
suspicious something in the planer itself is giving with an irregular
geometry.


I'm with you on that suspicion.

OK, thanks for hanging in here as long as you have. I'm going to give this
a rest for a while. I have enough flattened and thickness-planned boards to
actually start building the bench for my daughter. All twisted boards were
cut 10 - 12" inches longer than needed just to be safe, so lopping off the
thinner end is not an issue - for this project, at least. I wouldn't try
this with an expensive/limited amount piece of wood until a solution is
found, but for now it's time to get building.

Thanks again.