Cross Cut Sled Fence - Bowed At Kerf

On Wednesday, February 11, 2015 at 2:41:14 PM UTC-5, dadiOH wrote:
> "DerbyDad03" <[email protected]> wrote in message
> news:[email protected]
>=20
> > What are your thoughts on sandpaper on the face of the fence?
>=20
> You didn't ask me but I've finished my work for the day so I'll butt in=
=20
> anyway :)
>=20
> All it does is make the piece you are going to cut harder to position.
>=20

That's what I thought.

Some descriptions of sleds say that adhesive backed sandpaper helps keep th=
e material firmly positioned on the fence, others (like the Wood Whisperer)=
suggest a smooth surface which I assume is for *ease* of positioning, espe=
cially when making repeated cuts from the same piece of material.

On Tuesday, February 10, 2015 at 2:14:29 PM UTC-5, dadiOH wrote:
> "dpb" <[email protected]> wrote in message news:[email protected]
> > On 02/10/2015 10:41 AM, DerbyDad03 wrote:
> > ...
> >
> > > Last weekend I built a cross cut sled, ...
> > > http://www.youtube.com/watch?v=3DuE9f4bp_wm8
> > >
> > > My fence was made from a 4" tall piece of 3/4" melamine covered
> > > composite material ...
> > ...
> > > ... the single screw I had placed in the center area of the fence. As
> > > soon as I removed that screw, the bow disappeared and the fence is
> > > nowonce again flat across the face.
> > ...
> >
> > I think the problem basically is the 3/4" laminate simply isn't
> > stout-enough material for the purpose. I notice in his video it appear=
s
> > to be at a minimum 1+" and guessing 1-1/2" maybe???
> >
> > I generally use hard maple or similar hardwood of about that thickness
> > for the purpose.
>=20
> Or 2 layers of decent 3/4 ply.
>
=20
I originally glued up 2 cutoffs from the 1/2" ply I used for the base to cr=
eate a 1" fence. It was not perfectly flat, so while chatting with my neigh=
bor he offered the 3/4" melamine covered option. I was going to buy a piece=
of hardwood, but decided to try his suggestion first.

If I have anymore issues with the current fence, I'll probably go the hardw=
ood route.

On Tuesday, February 10, 2015 at 12:14:20 PM UTC-5, -MIKE- wrote:
> On 2/10/15 10:56 AM, dpb wrote:
> > On 02/10/2015 10:41 AM, DerbyDad03 wrote: ...
> >
> >> Last weekend I built a cross cut sled, ...
> >> http://www.youtube.com/watch?v=uE9f4bp_wm8
> >>
> >> My fence was made from a 4" tall piece of 3/4" melamine covered
> >> composite material ...
> > ...
> >> ... the single screw I had placed in the center area of the fence.
> >> As soon as I removed that screw, the bow disappeared and the fence
> >> is nowonce again flat across the face.
> > ...
> >
> > I think the problem basically is the 3/4" laminate simply isn't
> > stout-enough material for the purpose. I notice in his video it
> > appears to be at a minimum 1+" and guessing 1-1/2" maybe???
> >
> > I generally use hard maple or similar hardwood of about that
> > thickness for the purpose.
> >
> > --
>
> I agree. The fence he uses in the video appears to be built up finish
> plywood, at least 1-1/4' thick. It should also be checked for straight
> and flat before attaching. Plywood can warp, too.

I assume you didn't watch the entire video - and that's OK...

If you scroll to 3:50, you'll see that the fence he used is made from 1 1/8" HDO plywood with a "resin impregnated fiber" coating. He called it "regular plywood on steroids." At 7:00 Marc does indeed check it for flatness *before* installing it, as did I.

The point I was making is that he doesn't check it for flatness *after* installing it. That was when I found the bow caused by the screw. I'm not sure how the screw caused the bow, but I will be much more careful when I install the new screws tonight.

>
> I used a simple 2x4 for my fence. My intention was to build a
> prototype, then make a "good" one using better materials. But heck if
> that prototype didn't turn out perfect! No need for another.

As I often say: "It's only temporary...unless it works."

...snip...

On Tuesday, February 10, 2015 at 3:04:29 PM UTC-5, Max wrote:
> On 2/10/2015 12:16 PM, Dan Coby wrote:
> > On 2/10/2015 8:41 AM, DerbyDad03 wrote:
> >> This just a tip/warning that I thought you folks might want to be
> >> aware of...
> >>
> >> Last weekend I built a cross cut sled, following the techniques used
> >> in The Wood Whisperer, Epsiode 146. If you scroll forward to 8
> >> minutes, you will see the portion of the video where Marc attaches the
> >> fence and then aligns it using the 5 cut method.
> >>
> >> http://www.youtube.com/watch?v=uE9f4bp_wm8
> >>
> >> My fence was made from a 4" tall piece of 3/4" melamine covered
> >> composite material that my neighbor gave me. He uses scraps he has for
> >> sacrificial fences since the material is perfectly flat and smooth.
> >>
> >> I went through the alignment process and then test cut a few pieces of
> >> 1 x 6 poplar. The fence was initially aligned using the left side of
> >> the kerf and all boards were fed from that side i.e cutting off small
> >> strips and small ends from the right side of the boards. I was quite
> >> satisfied with the squareness of the cuts.
> >>
> >> Both ends of the fence were screwed to the sled as part of the
> >> alignment process, and then when I was satisfied, I added one more
> >> screw just to the right of the kerf, planning to add more screws once
> >> I was sure that everything was aligned to my compete satisfaction. I'm
> >> glad I waited.
> >>
> >> Last night, I decided to make a few zero clearance insert blanks from
> >> some true 1/4" hardwood plywood left over from some old drawers. Since
> >> the panel was ~14" wide, it spanned the kerf in the fence more than
> >> anything I had used for my test cuts. That's when I noticed that there
> >> was a gap between the fence and the far right side of the panel. As
> >> first I thought there was an issue with the panel, but I decided to
> >> check the fence with a straightedge. There was indeed a slight bow in
> >> the fence right at the kerf.
> >>
> >> I bent down and looked under the sled and saw the single screw I had
> >> placed in the center area of the fence. As soon as I removed that
> >> screw, the bow disappeared and the fence is now once again flat across
> >> the face.
> >>
> >> I went back and watched the video again and I didn't see any mention
> >> of Marc checking the face of fence once it is secured to the sled. My
> >> next step will be to carefully pre-drill for more screws, starting
> >> from right, working towards the kerf and checking the flatness after
> >> each screw is secured.
> >>
> >> Just something to keep in mind...
> >>
> >
> > I will add my experience on building a crosscut sled.
> >
> > I checked my alignment after I added screws to help hold the fence
> > aligned. The alignment was fine before adding the screws but off after
> > adding screws. The process of torquing down the screws took the fence
> > out of alignment. To fix the problem, I finally realigned the fence and
> > alternated gradually tightening the screws to keep the fence square.
> >
> >
> > Dan
>
> Just like torquing lug nuts or manifold bolts or.....

I torqued the manifold bolts on the cross cut sled to 30 ft-lbs.

On 2/10/2015 12:16 PM, Dan Coby wrote:
> On 2/10/2015 8:41 AM, DerbyDad03 wrote:
>> This just a tip/warning that I thought you folks might want to be
>> aware of...
>>
>> Last weekend I built a cross cut sled, following the techniques used
>> in The Wood Whisperer, Epsiode 146. If you scroll forward to 8
>> minutes, you will see the portion of the video where Marc attaches the
>> fence and then aligns it using the 5 cut method.
>>
>> http://www.youtube.com/watch?v=uE9f4bp_wm8
>>
>> My fence was made from a 4" tall piece of 3/4" melamine covered
>> composite material that my neighbor gave me. He uses scraps he has for
>> sacrificial fences since the material is perfectly flat and smooth.
>>
>> I went through the alignment process and then test cut a few pieces of
>> 1 x 6 poplar. The fence was initially aligned using the left side of
>> the kerf and all boards were fed from that side i.e cutting off small
>> strips and small ends from the right side of the boards. I was quite
>> satisfied with the squareness of the cuts.
>>
>> Both ends of the fence were screwed to the sled as part of the
>> alignment process, and then when I was satisfied, I added one more
>> screw just to the right of the kerf, planning to add more screws once
>> I was sure that everything was aligned to my compete satisfaction. I'm
>> glad I waited.
>>
>> Last night, I decided to make a few zero clearance insert blanks from
>> some true 1/4" hardwood plywood left over from some old drawers. Since
>> the panel was ~14" wide, it spanned the kerf in the fence more than
>> anything I had used for my test cuts. That's when I noticed that there
>> was a gap between the fence and the far right side of the panel. As
>> first I thought there was an issue with the panel, but I decided to
>> check the fence with a straightedge. There was indeed a slight bow in
>> the fence right at the kerf.
>>
>> I bent down and looked under the sled and saw the single screw I had
>> placed in the center area of the fence. As soon as I removed that
>> screw, the bow disappeared and the fence is now once again flat across
>> the face.
>>
>> I went back and watched the video again and I didn't see any mention
>> of Marc checking the face of fence once it is secured to the sled. My
>> next step will be to carefully pre-drill for more screws, starting
>> from right, working towards the kerf and checking the flatness after
>> each screw is secured.
>>
>> Just something to keep in mind...
>>
>
> I will add my experience on building a crosscut sled.
>
> I checked my alignment after I added screws to help hold the fence
> aligned. The alignment was fine before adding the screws but off after
> adding screws. The process of torquing down the screws took the fence
> out of alignment. To fix the problem, I finally realigned the fence and
> alternated gradually tightening the screws to keep the fence square.
>
>
> Dan

Just like torquing lug nuts or manifold bolts or.....

On 2/10/2015 1:13 PM, DerbyDad03 wrote:
> On Tuesday, February 10, 2015 at 3:04:29 PM UTC-5, Max wrote:

>> Just like torquing lug nuts or manifold bolts or.....
>
> I torqued the manifold bolts on the cross cut sled to 30 ft-lbs.
>

;-)

"DerbyDad03" wrote:

I bent down and looked under the sled and saw the single screw I had
placed in the center area of the fence. As soon as I removed that
screw, the bow disappeared and the fence is now once again flat across
the face.
----------------------------------------------
As others have suggested, too small a pilot hole and 3/4" stock
requires screws to be dead nuts on center, which leaves very
little for error.

SFWIW, I use 75% of full body dia for pilot drill dia.

Haven't stripped a screw yet.

Lew

On 02/11/2015 01:05 PM, DerbyDad03 wrote:
> On Wednesday, February 11, 2015 at 2:41:14 PM UTC-5, dadiOH wrote:
>> "DerbyDad03" <[email protected]> wrote in message
>> news:[email protected]
>>
>>> What are your thoughts on sandpaper on the face of the fence?
>>
>> You didn't ask me but I've finished my work for the day so I'll butt in
>> anyway :)
>>
>> All it does is make the piece you are going to cut harder to position.
>>
>
> That's what I thought.
>
> Some descriptions of sleds say that adhesive backed sandpaper helps keep the material firmly positioned on the fence, others (like the Wood Whisperer) suggest a smooth surface which I assume is for *ease* of positioning, especially when making repeated cuts from the same piece of material.
>

Where it does help is with a miter sled.



--
"Socialism is a philosophy of failure,the creed of ignorance, and the
gospel of envy, its inherent virtue is the equal sharing of misery"
-Winston Churchill

On Tuesday, February 10, 2015 at 11:16:11 AM UTC-8, Dan Coby wrote:

> I will add my experience on building a crosscut sled.
>
> I checked my alignment after I added screws to help hold the fence
> aligned. The alignment was fine before adding the screws but off after
> adding screws. The process of torquing down the screws took the fence
> out of alignment.

If I care about alignment (usually do, in any jig), I predrill and drive
one nail as a pivot, then glue the piece into position. When the glue
is set, before using the assembly, I predrill and screw along the glue
joint so it won't break. Optionally, also remove the nail...

This allows me to get good results even with hotmelt glue (which
allows later disassembly for adjustment). Predrilling is key, a bit
of woodgrain can cock a sheetrock screw badly, and has some
effect even on shanked woodscrews.

On Wednesday, February 11, 2015 at 8:29:19 AM UTC-5, Swingman wrote:
> On 2/10/2015 1:34 PM, DerbyDad03 wrote:
> ginally glued up 2 cutoffs from the 1/2" ply I used for the base to
> create a 1" fence. It was not perfectly flat, so while chatting with my
> neighbor he offered the 3/4" melamine covered option. I was going to buy
> a piece of hardwood, but decided to try his suggestion first.
> >
> > If I have anymore issues with the current fence, I'll probably go the hardwood route.
>
> Or, laminate both plywood, and hardwood(for the critical face of the fence):

Good idea.
>
> http://e-woodshop.net/images/SmallTableSled.JPG
>
> Ran the (scrap) walnut face across the jointer for "flat".
>
> My goto crosscut sled for just about all crosscutting under 12", that
> puppy has been rock solid for years.
>
> (it has white oak runners, routinely waxed)

What are your thoughts on sandpaper on the face of the fence?

DerbyDad03 <[email protected]> wrote in
news:[email protected]:

> I added one more
> screw just to the right of the kerf, planning to add more screws once
> I was sure that everything was aligned to my compete satisfaction. I'm
> glad I waited.

<...>

> I bent down and looked under the sled and saw the single screw I had
> placed in the center area of the fence. As soon as I removed that
> screw, the bow disappeared and the fence is now once again flat across
> the face.
>
> My
> next step will be to carefully pre-drill for more screws, starting
> from right, working towards the kerf and checking the flatness after
> each screw is secured.

I have seen the same thing happen in various situations,
where putting a screw in the center pulls a piece out of
line. It's always better to work from one end to the
other, or from the center out to both ends, than it is
to do the ends and then the center.

John

On 2/10/2015 1:34 PM, DerbyDad03 wrote:
ginally glued up 2 cutoffs from the 1/2" ply I used for the base to
create a 1" fence. It was not perfectly flat, so while chatting with my
neighbor he offered the 3/4" melamine covered option. I was going to buy
a piece of hardwood, but decided to try his suggestion first.
>
> If I have anymore issues with the current fence, I'll probably go the hardwood route.

Or, laminate both plywood, and hardwood(for the critical face of the fence):

http://e-woodshop.net/images/SmallTableSled.JPG

Ran the (scrap) walnut face across the jointer for "flat".

My goto crosscut sled for just about all crosscutting under 12", that
puppy has been rock solid for years.

(it has white oak runners, routinely waxed)

--
eWoodShop: www.eWoodShop.com
Wood Shop: www.e-WoodShop.net
https://www.google.com/+eWoodShop
https://plus.google.com/+KarlCaillouet/posts
http://www.custommade.com/by/ewoodshop/
KarlCaillouet@ (the obvious)

On Wednesday, February 11, 2015 at 6:53:57 AM UTC-5, dadiOH wrote:
> "DerbyDad03" <[email protected]> wrote in message
> news:[email protected]
> > On Tuesday, February 10, 2015 at 2:14:29 PM UTC-5, dadiOH wrote:
> > > "dpb" <[email protected]> wrote in message news:[email protected]
> > > > On 02/10/2015 10:41 AM, DerbyDad03 wrote:
> > > > ...
> > > >
> > > > > Last weekend I built a cross cut sled, ...
> > > > > http://www.youtube.com/watch?v=uE9f4bp_wm8
> > > > >
> > > > > My fence was made from a 4" tall piece of 3/4" melamine covered
> > > > > composite material ...
> > > > ...
> > > > > ... the single screw I had placed in the center area of the fence.
> > > > > As soon as I removed that screw, the bow disappeared and the fence
> > > > > is nowonce again flat across the face.
> > > > ...
> > > >
> > > > I think the problem basically is the 3/4" laminate simply isn't
> > > > stout-enough material for the purpose. I notice in his video it
> > > > appears to be at a minimum 1+" and guessing 1-1/2" maybe???
> > > >
> > > > I generally use hard maple or similar hardwood of about that
> > > > thickness
> > > > for the purpose.
> > >
> > > Or 2 layers of decent 3/4 ply.
> > >
> >
> > I originally glued up 2 cutoffs from the 1/2" ply I used for the base to
> > create a 1" fence. It was not perfectly flat,
>
> If/when you need to make a thicker piece of ply by gluing together two
> thinner ones, cut them from the same sheet and glue face "A" to face "A".
> If they didn't start out flat - like most all borgply - this will *help*
> flatten both thereby minimizing the additional work needed for total
> flatness.
>
That's what I did and while it *helped*, it still wasn't flat enough for my liking. The best of the 2 was used for the back fence, the other one is in the ever growing scrap pile.

On 2/10/2015 8:41 AM, DerbyDad03 wrote:
> This just a tip/warning that I thought you folks might want to be aware of...
>
> Last weekend I built a cross cut sled, following the techniques used in The Wood Whisperer, Epsiode 146. If you scroll forward to 8 minutes, you will see the portion of the video where Marc attaches the fence and then aligns it using the 5 cut method.
>
> http://www.youtube.com/watch?v=uE9f4bp_wm8
>
> My fence was made from a 4" tall piece of 3/4" melamine covered composite material that my neighbor gave me. He uses scraps he has for sacrificial fences since the material is perfectly flat and smooth.
>
> I went through the alignment process and then test cut a few pieces of 1 x 6 poplar. The fence was initially aligned using the left side of the kerf and all boards were fed from that side i.e cutting off small strips and small ends from the right side of the boards. I was quite satisfied with the squareness of the cuts.
>
> Both ends of the fence were screwed to the sled as part of the alignment process, and then when I was satisfied, I added one more screw just to the right of the kerf, planning to add more screws once I was sure that everything was aligned to my compete satisfaction. I'm glad I waited.
>
> Last night, I decided to make a few zero clearance insert blanks from some true 1/4" hardwood plywood left over from some old drawers. Since the panel was ~14" wide, it spanned the kerf in the fence more than anything I had used for my test cuts. That's when I noticed that there was a gap between the fence and the far right side of the panel. As first I thought there was an issue with the panel, but I decided to check the fence with a straightedge. There was indeed a slight bow in the fence right at the kerf.
>
> I bent down and looked under the sled and saw the single screw I had placed in the center area of the fence. As soon as I removed that screw, the bow disappeared and the fence is now once again flat across the face.
>
> I went back and watched the video again and I didn't see any mention of Marc checking the face of fence once it is secured to the sled. My next step will be to carefully pre-drill for more screws, starting from right, working towards the kerf and checking the flatness after each screw is secured.
>
> Just something to keep in mind...
>

I will add my experience on building a crosscut sled.

I checked my alignment after I added screws to help hold the fence
aligned. The alignment was fine before adding the screws but off after
adding screws. The process of torquing down the screws took the fence
out of alignment. To fix the problem, I finally realigned the fence and
alternated gradually tightening the screws to keep the fence square.


Dan

On 02/10/2015 10:41 AM, DerbyDad03 wrote:
...

> Last weekend I built a cross cut sled, ...
> http://www.youtube.com/watch?v=uE9f4bp_wm8
>
> My fence was made from a 4" tall piece of 3/4" melamine covered
> composite material ...
...
> ... the single screw I had placed in the center area of the fence. As
> soon as I removed that screw, the bow disappeared and the fence is
> nowonce again flat across the face.
...

I think the problem basically is the 3/4" laminate simply isn't
stout-enough material for the purpose. I notice in his video it appears
to be at a minimum 1+" and guessing 1-1/2" maybe???

I generally use hard maple or similar hardwood of about that thickness
for the purpose.

--

On 2/10/15 10:56 AM, dpb wrote:
> On 02/10/2015 10:41 AM, DerbyDad03 wrote: ...
>
>> Last weekend I built a cross cut sled, ...
>> http://www.youtube.com/watch?v=uE9f4bp_wm8
>>
>> My fence was made from a 4" tall piece of 3/4" melamine covered
>> composite material ...
> ...
>> ... the single screw I had placed in the center area of the fence.
>> As soon as I removed that screw, the bow disappeared and the fence
>> is nowonce again flat across the face.
> ...
>
> I think the problem basically is the 3/4" laminate simply isn't
> stout-enough material for the purpose. I notice in his video it
> appears to be at a minimum 1+" and guessing 1-1/2" maybe???
>
> I generally use hard maple or similar hardwood of about that
> thickness for the purpose.
>
> --

I agree. The fence he uses in the video appears to be built up finish
plywood, at least 1-1/4' thick. It should also be checked for straight
and flat before attaching. Plywood can warp, too.

I used a simple 2x4 for my fence. My intention was to build a
prototype, then make a "good" one using better materials. But heck if
that prototype didn't turn out perfect! No need for another.

I passed the 2x4 over the jointer a few times, then through the planer.
That made it perfectly flat and straight.


--

-MIKE-

"Playing is not something I do at night, it's my function in life"
--Elvin Jones (1927-2004)
--
http://mikedrums.com
[email protected]
---remove "DOT" ^^^^ to reply

On 2/10/15 11:54 AM, DerbyDad03 wrote:
> On Tuesday, February 10, 2015 at 12:14:20 PM UTC-5, -MIKE- wrote:
>> On 2/10/15 10:56 AM, dpb wrote:
>>> On 02/10/2015 10:41 AM, DerbyDad03 wrote: ...
>>>
>>>> Last weekend I built a cross cut sled, ...
>>>> http://www.youtube.com/watch?v=uE9f4bp_wm8
>>>>
>>>> My fence was made from a 4" tall piece of 3/4" melamine covered
>>>> composite material ...
>>> ...
>>>> ... the single screw I had placed in the center area of the
>>>> fence. As soon as I removed that screw, the bow disappeared
>>>> and the fence is nowonce again flat across the face.
>>> ...
>>>
>>> I think the problem basically is the 3/4" laminate simply isn't
>>> stout-enough material for the purpose. I notice in his video it
>>> appears to be at a minimum 1+" and guessing 1-1/2" maybe???
>>>
>>> I generally use hard maple or similar hardwood of about that
>>> thickness for the purpose.
>>>
>>> --
>>
>> I agree. The fence he uses in the video appears to be built up
>> finish plywood, at least 1-1/4' thick. It should also be checked
>> for straight and flat before attaching. Plywood can warp, too.
>
> I assume you didn't watch the entire video - and that's OK...
>

I don't have to, I've made them myself.


> If you scroll to 3:50, you'll see that the fence he used is made
> from 1 1/8" HDO plywood with a "resin impregnated fiber" coating. He
> called it "regular plywood on steroids." At 7:00 Marc does indeed
> check it for flatness *before* installing it, as did I.
>
> The point I was making is that he doesn't check it for flatness
> *after* installing it. That was when I found the bow caused by the
> screw. I'm not sure how the screw caused the bow, but I will be much
> more careful when I install the new screws tonight.
>

The real point is, you used 3/4" material. I don't think that's stable
enough. Screwing into it is enough to move it one way or another ever
so slightly.
You may consider (even on a thicker fence) screwing it to the base using
pocket screws with a washer in an enlarged hole. This way it can be
fine tuned when tightened and readjusted for seasonal movement.


>>
>> I used a simple 2x4 for my fence. My intention was to build a
>> prototype, then make a "good" one using better materials. But
>> heck if that prototype didn't turn out perfect! No need for
>> another.
>
> As I often say: "It's only temporary...unless it works."
>
> ...snip...
>

I have a ton of "temporary" jigs and tools in my shop that are still
going strong. :-)


--

-MIKE-

"Playing is not something I do at night, it's my function in life"
--Elvin Jones (1927-2004)
--
http://mikedrums.com
[email protected]
---remove "DOT" ^^^^ to reply

On 02/10/2015 11:54 AM, DerbyDad03 wrote:
...

> If you scroll to 3:50, you'll see that the fence he used is made
> from 1 1/8" HDO plywood ...

Which is at least 3/8" thicker than your 3/4" (and 50% as a percentage)...

> The point I was making is that he doesn't check it for flatness
> *after* installing it. That was when I found the bow caused by the
> screw. I'm not sure how the screw caused the bow, but I will be much
> more careful when I install the new screws tonight.

...

Because he had sufficiently-stout material that moving it wasn't likely
to be an issue...it never hurts to check, yes, but imo in your case it's
inevitable in that the material simply isn't very rigid owing to it's
thinness or lack of bulk.

The "how" is likely that your screw tip hit the edge of one of the plies
instead of dead center either in or between and that difference in
hardness pushed the material to the side instead of letting the screw
penetrate straight in at the starting location.

That's what doesn't happen with the stouter material, or at least not
nearly so likely and with clear hardwood isn't nearly the issue as with
the ply.

--

"dpb" <[email protected]> wrote in message news:[email protected]
> On 02/10/2015 10:41 AM, DerbyDad03 wrote:
> ...
>
> > Last weekend I built a cross cut sled, ...
> > http://www.youtube.com/watch?v=uE9f4bp_wm8
> >
> > My fence was made from a 4" tall piece of 3/4" melamine covered
> > composite material ...
> ...
> > ... the single screw I had placed in the center area of the fence. As
> > soon as I removed that screw, the bow disappeared and the fence is
> > nowonce again flat across the face.
> ...
>
> I think the problem basically is the 3/4" laminate simply isn't
> stout-enough material for the purpose. I notice in his video it appears
> to be at a minimum 1+" and guessing 1-1/2" maybe???
>
> I generally use hard maple or similar hardwood of about that thickness
> for the purpose.

Or 2 layers of decent 3/4 ply.

--

dadiOH
____________________________

Winters getting colder? Tired of the rat race?
Taxes out of hand? Maybe just ready for a change?
Check it out... http://www.floridaloghouse.net

"DerbyDad03" <[email protected]> wrote in message
news:[email protected]
> On Tuesday, February 10, 2015 at 2:14:29 PM UTC-5, dadiOH wrote:
> > "dpb" <[email protected]> wrote in message news:[email protected]
> > > On 02/10/2015 10:41 AM, DerbyDad03 wrote:
> > > ...
> > >
> > > > Last weekend I built a cross cut sled, ...
> > > > http://www.youtube.com/watch?v=uE9f4bp_wm8
> > > >
> > > > My fence was made from a 4" tall piece of 3/4" melamine covered
> > > > composite material ...
> > > ...
> > > > ... the single screw I had placed in the center area of the fence.
> > > > As soon as I removed that screw, the bow disappeared and the fence
> > > > is nowonce again flat across the face.
> > > ...
> > >
> > > I think the problem basically is the 3/4" laminate simply isn't
> > > stout-enough material for the purpose. I notice in his video it
> > > appears to be at a minimum 1+" and guessing 1-1/2" maybe???
> > >
> > > I generally use hard maple or similar hardwood of about that
> > > thickness
> > > for the purpose.
> >
> > Or 2 layers of decent 3/4 ply.
> >
>
> I originally glued up 2 cutoffs from the 1/2" ply I used for the base to
> create a 1" fence. It was not perfectly flat,

If/when you need to make a thicker piece of ply by gluing together two
thinner ones, cut them from the same sheet and glue face "A" to face "A".
If they didn't start out flat - like most all borgply - this will *help*
flatten both thereby minimizing the additional work needed for total
flatness.

--

dadiOH
____________________________

Winters getting colder? Tired of the rat race?
Taxes out of hand? Maybe just ready for a change?
Check it out... http://www.floridaloghouse.net

"DerbyDad03" <[email protected]> wrote in message
news:[email protected]

> What are your thoughts on sandpaper on the face of the fence?

You didn't ask me but I've finished my work for the day so I'll butt in
anyway :)

All it does is make the piece you are going to cut harder to position.


--

dadiOH
____________________________

Winters getting colder? Tired of the rat race?
Taxes out of hand? Maybe just ready for a change?
Check it out... http://www.floridaloghouse.net

On 2/11/2015 9:00 AM, DerbyDad03 wrote:

> What are your thoughts on sandpaper on the face of the fence?

Never bothered with it.

99% of the time I use a stop block or the TS fence, so it really isn't
necessary.

--
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