I purchased a 13 inch Jet planer/molder. After initial setup I was
able to easily thickness plane lumber. The results were excellent. I
think they may be too smooth - will need to sand a bit to get some
tooth for the paint to grab on to.

I am now trying to use the molder feature. The initial knives are
just used to plough out a 2 inch wide by .25 inch deep groove in a
1x4x 3/4" board. This is just the relief on the back of the molding.
I have determined that the instructions in the manual for setting up
the molding feature are totally bogus. It calls for the feed roller
to be initially set 5/16" below the level of the molding knives.
Even when the rollers are all the way down, I can't get them that far
below the knives. I set the rollers down as far as possible and tried
it. The feed pressure to start the board through the planer was very
high. Furthermore, as I raised the bed 1/8" for the first cut, the
roller pressure pressure increased significantly. By the time I did
the 2nd pass to get my final 1/4" it was nearly impossible to get it
started. Basically, each increase of 1/8" caused the rollers to be
under more pressure.

Has anybody got some experience, expertise, or hints they wish to
share about using this beast?

wrote in message
...
I purchased a 13 inch Jet planer/molder. After initial setup I was
able to easily thickness plane lumber. The results were excellent. I
think they may be too smooth - will need to sand a bit to get some
tooth for the paint to grab on to.

I am now trying to use the molder feature. The initial knives are
just used to plough out a 2 inch wide by .25 inch deep groove in a
1x4x 3/4" board. This is just the relief on the back of the molding.
I have determined that the instructions in the manual for setting up
the molding feature are totally bogus. It calls for the feed roller
to be initially set 5/16" below the level of the molding knives.
Even when the rollers are all the way down, I can't get them that far
below the knives. I set the rollers down as far as possible and tried
it. The feed pressure to start the board through the planer was very
high. Furthermore, as I raised the bed 1/8" for the first cut, the
roller pressure pressure increased significantly. By the time I did
the 2nd pass to get my final 1/4" it was nearly impossible to get it
started. Basically, each increase of 1/8" caused the rollers to be
under more pressure.

Has anybody got some experience, expertise, or hints they wish to
share about using this beast?

I've got one of those...

For backing out, on what is essentially a flat board, I'd leave the feed
roller in the same position as it is for "normal" planning and try it. For
some moldings the outfeed roller needs to be lower so it actually does
something but infeed on a flat board shouldn't require such an extreme
setting... This in my experience. Others may have had other experiences.

I'd also reconsider .25" deep backing... that is really deep. An 1/8" is
generally more than enough. Of course if you have some really rough surfaces
your installing over 25" may be appropriate.

John

On 10/5/2011 6:46 AM, John Grossbohlin wrote:
....

For backing out, on what is essentially a flat board, I'd leave the feed
roller in the same position as it is for "normal" planning and try it.
For some moldings the outfeed roller needs to be lower so it actually
does something but infeed on a flat board shouldn't require such an
extreme setting... This in my experience. Others may have had other
experiences.

I'd also reconsider .25" deep backing... that is really deep. An 1/8" is
generally more than enough. Of course if you have some really rough
surfaces your installing over 25" may be appropriate.
....

Troo-dat on both. The only reason need to lower the feed roller is when
the full thickness is removed so the next feed is thinner stock;
otherwise you still have the same material thickness overall.

(I don't have the specific moulder/planer, but only makes sense...)

Also on the backcut--standard moulding profiles back-relief generally is
only about 1/16", even 1/8" is quite a lot for the purpose.

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