"Leon" <[email protected]> wrote in message
news:[email protected]...
>
> "samson" <[email protected]> wrote in message
> news:[email protected]...
>> There must have been an extra big gravel of sand on
>> my sand paper, because my palm sander left a tiny
>> spring-shaped line all across the front of my project.
>> Worse, I couldn't see it until I put on some finish.
>> Crap!
>>
>> S.
>
> Did you wipe the surface of all dust when changing grits?
>
And run your hand over everything before you finished? I often find small
irregularities by feel rather than by sight.
In article <[email protected]>,
Scritch <[email protected]> wrote:
> Not on this subject, but I was sanding the other day with my ROS, and
> noticed that the vibration of the sander was making my wedding ring spin
> around!
That's a worryingly dangerous amount of vibration.
Have you ever heard of something called "whitefinger", it's caused by
subjecting your hands/arms to too much vibration.
http://patient.co.uk/showdoc/23069104
--
Stuart Winsor
For Barn dances and folk evenings in the Coventry and Warwickshire area
See: http://www.barndance.org.uk
On Oct 26, 10:19 pm, samson <[email protected]> wrote:
> There must have been an extra big gravel of sand on
> my sand paper, because my palm sander left a tiny
> spring-shaped line all across the front of my project.
> Worse, I couldn't see it until I put on some finish.
You couldn't see it because we like to flood our shops with overhead
lighting but a raking light is what you need to expose all the little
flaws. Usually I don't worry about it until I hit 150 grit, then
either I pick up the piece to get the surface between me and the light
source or I move a light if it's not feasible to lift the work. Mark
all the problem areas with a pencil and back up on the grits. Repeat
until everything looks consistent at 150 grit. Then move on finer if
not staining.
There was an episode of Dirty Jobs where they make surfboards. In the
room where they carve the foam of the board they had two lighting
systems. The general overheard lights and rows of pot lights set on
two walls just above the surface the boards. With the overhead lights
on you couldn't see any detail on the foam. Switch to the raking
lights and voila, everything is clear as day. Kind of like when you
repaint a wall in an old house. As long as you point the lights
straight at the wall it looks half decent. The second you move the
light parallel to the wall you recoil in horror at all the bad patch
jobs and holes.
-Kevin
In article <[email protected]>,
[email protected] says...
> In article <[email protected]>,
> samson <[email protected]> wrote:
>
> > There must have been an extra big gravel of sand on
> > my sand paper, because my palm sander left a tiny
> > spring-shaped line all across the front of my project.
> > Worse, I couldn't see it until I put on some finish.
> > Crap!
> >
> > S.
>
> As already mentioned, that could have been a grain from a previous paper.
> If I know I'm going to stain, I always blow off in between grits and
> wipe with a clean rag, wetted down with methyl hydrate.
> That will show any snake tracks or other scratches.
Lots of good information. Thanks guys.
S.
In article <[email protected]>,
[email protected] says...
> There must have been an extra big gravel of sand on
> my sand paper, because my palm sander left a tiny
> spring-shaped line all across the front of my project.
> Worse, I couldn't see it until I put on some finish.
> Crap!
>
> S.
>
cleaning the work piece with compressed air from time to time
at the very tail end of the prepping will usually show up any such
scratches, that are often invisible due to being filled with fine
compressed sawdust.
-P.
"samson" <[email protected]> wrote in message
news:[email protected]...
> There must have been an extra big gravel of sand on
> my sand paper, because my palm sander left a tiny
> spring-shaped line all across the front of my project.
> Worse, I couldn't see it until I put on some finish.
> Crap!
>
> S.
Did you wipe the surface of all dust when changing grits?
samson <[email protected]> wrote in
news:[email protected]:
> There must have been an extra big gravel of sand on
> my sand paper, because my palm sander left a tiny
> spring-shaped line all across the front of my project.
> Worse, I couldn't see it until I put on some finish.
> Crap!
>
> S.
Not on this subject, but I was sanding the other day with my ROS, and
noticed that the vibration of the sander was making my wedding ring spin
around!
In article <[email protected]>,
samson <[email protected]> wrote:
> There must have been an extra big gravel of sand on
> my sand paper, because my palm sander left a tiny
> spring-shaped line all across the front of my project.
> Worse, I couldn't see it until I put on some finish.
> Crap!
>
> S.
As already mentioned, that could have been a grain from a previous paper.
If I know I'm going to stain, I always blow off in between grits and
wipe with a clean rag, wetted down with methyl hydrate.
That will show any snake tracks or other scratches.
In article <[email protected]>,
"Rick Samuel" <[email protected]> wrote:
> >>> S.
> >>
> >> Did you wipe the surface of all dust when changing grits?
> >>
> > And run your hand over everything before you finished? I often find small
> > irregularities by feel rather than by sight.
> >
>
> Ive been a machinist for 40 years now, and it never ceases to amaze me at
> what a finger tip or nail can feel.
Isn't that the truth. Snake tracks are elusive though. Not as easily
felt as straight grooves. Making the dust moist with methyl hydrate,
then wiping the dust into the grooves, will show them nice and bright as
the methyl dries... it dries a bit slower in the grooves. It also raises
the grain a wee bit and give a preview of what kind of figure is
awaiting a proper finish.
>>> S.
>>
>> Did you wipe the surface of all dust when changing grits?
>>
> And run your hand over everything before you finished? I often find small
> irregularities by feel rather than by sight.
>
Ive been a machinist for 40 years now, and it never ceases to amaze me at
what a finger tip or nail can feel.
"Scritch" <[email protected]> wrote in message
>
> Not on this subject, but I was sanding the other day with my ROS, and
> noticed that the vibration of the sander was making my wedding ring spin
> around!
Put the ROS in the right place and your wife will spin around