|Home » Forums » Architectural Woodworking » Message||Login|
You are not logged in. Consider these WOODWEB Member advantages:
sanding profiled trim and molding8/12
Im actually a finisher , and am looking for a faster method of sanding trim and molding . willingness to do the sanding may mean more work coming my way in the near future , but I need a faster method than doing it by hand .
I recently stumbled upon this : https://www.youtube.com/watch?v=2H63cofkkts , and it looks interesting and geared to the low-usage user . . has anyone ever tried a product like this ? my main concern is what it can do with mill marks and chatter . any input on this would be highly appreciated
My experience is not flap style sander is going to remove chatter without removing details in the profile.
There are straight line sanders that use matching profile sanding blocks. That may be the route you need to go.
That type of brush is a joke compared to a tampico backed quality brush. Look at Flex Trim and Slip Con. I have worked for both of those companies and my current company sells a line of quality brushes as well.
A few quality brushes in line will remove knife marks and light lines in the cutter, but none of them are capable of removing chatter.
Chatter represents a contour that the brushes will follow and not simply a surface texture being sanded off.
Also, the brushes pictured require high speed to work at all. They tend to buff the surface instead of sand. 400 rpm on a quality brush with proper pressure will do a huge amount of sanding. At 1200 rpm those other brushes will hardly do anything.
3000 RPM! Holy crap! Haha!
10,000 whole feet of molding! Wow!
I have had quality brushes go over 500,000 lineal feet. That is assuming a proper brush at 300-600 rpm.
alright , thanks for the feedback guys . looks like I'll pass on the mop sander and continue researching . thanks for the leads .
Look up Larick machinery. Larry builds his stuff right for a good price. Opti sand is another good company.
Removing chatter @ the sanding stage is nearly hopeless. It should have been taken care of when the moldings were run. It is the result of poor molder setup. Some kinds of wood result in fine chipouts that just seem inherent in those woods.
Larry.......I agree . 80% of everything I finish comes from one guy......a guy and his shop , and always ready to stain or clearcoat . until this past spring , when I took a trim job which was from a big-box . homeowner didnt realize the difference ; and I didnt want it to look like crap so I sanded it myself,,,,,only 800' or so , but it sucked terribly doing it by hand . I charged hourly for sanding , advising that sanding is time consuming and hard to predict how long it will take . homeowner was cool with that , and I came out o.k. on it .
so I need to prepare for this in the future ....while keeping in mind that Im pretty low volume ; which to me means not to overspend . realistically I cant justify going over 500 bucks at this point....which sets quite a few limits .
The hub and strips will run almost $400. You will need a variable speed motor to build a reasonably useful machine yourself. You could use pulleys and fix it at 3 to 1 for around 600 rpm on an 1800 rpm motor. You will need about 3/4 hp.
I ran a 10 head Makor profile sander. We did white wood as well as scuff sanding with it, but even with that machine if the profiles weren't run properly on the molder it just wouldn't clean it up good enough. When the profiles were run clean the thing was incredible. We could run 10,000 lf of molding sanded, stained, sealed, glazed and top coated in 3 days. (could have ran more but that was all the racks we had)
so let me ask you guys this.....would stock purchased from a big box clean up if it were ran through a higher end molding sander ?
Im starting to wonder if my best bet would be to find a shop that can run it for me . kinda seems that any low cost solution isnt going to get the job done .
the Larick style looks great for raised panels , but I cant figure how they could be used for moulding or trim ; and each different profile would require a different wheel.....doesnt sound cost effective for small runs like what I get . but maybe Im missing the boat here .
it seems to me that the best way to remove heavy mill marks or chatter is with a hard backed sanding device ....100 grit paper on a hard backing , which forces the paper to contact the high spots first ; eventually the high spots are abraded down to the point of being flush with the low spots...and presto....no more chatter . this sounds like a wood sanding block....no ? but then the dilemma becomes how to shape a wood block to match a profile . this is where Im at now .....started looking into straight line sanders a bit , but havent yet found anything that uses profiled blocks .
Im even considering playing around with making my own custom blocks . maybe figure out a way to use this with a SL sander ? or make it long enough to allow 2 handles , thus allowing it to be used like a hand plane ? not a power application , but Id bet its still faster than the alternative .
and once again , I gotta say thanks for all the replies . very much appreciated . I can certainly share what I learn if anyone is interested .
I hate doing it but have made custom hand sanding blocks using Bondo over a wood block ruffed to size and pressed on to the molding with a pc. of sand paper the thickness I was going to used contact cemented to the molding. Use a pc. of stretch film, Saran wrap or whatever between the Bondo and sand paper as a release. You will have a perfect match and can put your sandpaper on that. In making your paper match the molding it may be necessary to use a sharp scribe to make the paper fit tight inside corners.
Then comes the really boring part, sanding. Yuk! Still faster than wearing out your fingers.
There is an alternative using Etha foam for the sanding block. shape it as close as you can, finish it by gluing sandpaper on the molding and rubbing like hell. Then glue the sandpaper to the foam.
None of these seem like fun to me but do work and don't cost much in time or materials to make.
Whether the trade off to the big box store crappy molding cheap price is worth it over paying a custom molding shop the higher price is (not very) debatable.
Even after you sand the high spots off there is still the compression set that will affect staining.
What is the cost difference between commercial molding and quality molding? I can't imagine the hand sanding pays for itself.
larry......thats exactly what I was thinking . and Im stirring around ideas of how to make the block easier to hang on to....attaching handles , ect . the worst part of sanding trim is how hard it is on my hands ; a more ergonomic grip would alleviate some of that .
I dont know about compression set ; the run that I sanded that came from big-box looked fantastic when it was done .
big box versus custom ? I dont know . if someone wants to pay me to sand it , I'll do it . but I'll always be looking to make my day easier . if they dont want me to sand it , then they would have to sand it themselves or take it elsewhere for the finishing . I wont do it if it looks like crap .
I agree with other's,you and the customer will be money ahead to buy quality molding from another place.I can't imagine the cheaper stuff is really cheaper once they pay you to put that much time into it.I buy all my trim from Keim Lumber,it comes sanded and is in primo shape from one end to the other,and does not cost that much more than the junk from the box stores.I consider the stuff from the box stores is what's used for rentals or people that are flipping houses to make a quick buck,it's not cost effective to try to turn that trim into something nice,it was never meant to be that way in the first place.
Keim lumber uses a brush sanding machine made by Opti-sand. 4 top heads and two side heads. They have a good molder.
Max...I stumbled across the Festool 130 last night . there seems to be quite a selection of profiled pads available . definitely be looking into it further . you say you have one ? how rigid/hard are the pads ? do you get a good bit of footage out of them ?
Moldingknivesdirect.com sells a hard foam sanding block that is a perfect negative of the molding. All that is required is psa back sandpaper that he sells as well. I have used it with satisfactory results. You can send him the profile you require, or if you buy knives from him, like I did, you get a discount. It makes sanding moldings with lots of nooks and crannies a lot easier.
From what i see, the Festool custom DIY pads are $57 for each foam block. I will look at it from my supplier.
I like the Dynabrade profile sander but they dont have many profiles. I wish they did.
Check out Soft Sanders foam sanding blocks. I use these for all my raised panels.
It all starts with the machine doing the profiling. The higher the rpms and the sharper the knives ( 2 knives are half as good as four) the less pitch u get on your finished profile. More often than not, making a final pass removing only 60 thousandths of an inch will allow u to use most of the sanding processes above. It's another pass which takes some time- but u can start your sanding process with #120 as opposed to #80. You should be using a Schmidt head on your shaper or sticker and make sure u hone the knives after they have been set in the head.
Danny, there is far more to running a quality molding than speed and sharpness. The larger diameter the head the shallower the "scallops." Since no knife instantly starts cutting on contact, there will be some initial compression of the fibers. The shallower the cut the more compression and the greater the heat generated. During compression the knife is rubbing, not cutting = heat. You need enough chip load to carry away that heat. The same thing happens with too high of RPM compared to feed.
As for knife count, it is back to the issue of chip load. If nothing else changes doubling the # of knives cuts the chip load in half. At some point that results in more heat, more compressed fibers and a poorer result. Unless you are running hydro heads there is slop between the bore and the spindle, otherwise you can't get them on & off. So the knives are never cutting an = amount. Back to that chip load thing. On a 4 knife head only one is likely doing the finishing cut.
Honing: If you are running a quality profile grinder there is no point in honing. If there is a very slight bur, wipe it off with a stick. If you feel you have to hone, only move the hone toward and away from the center of the spindle, never axially. If you hone axially you are actually causing more harm than good. The fine scratches left by the hone create a weak edge because the grooves left right behind the edge reduce the thickness of metal there. The result will be that leading edge will have a very small piece of metal fold over & break off much sooner than it it wasn't there.
Not all woods react the same. Straight grained basswood VS curly maple. The hook angle of the head used for bass wood can be much sharper than that used for the maple. 25 degrees? VS maple @ 12! If you run the maple @ 25 you will lift chunks out at every grain reversal. Higher hook angles usually result in freer cutting and smoother finish. Knives are ground with the appropriate clearance angle depending on the slots you are going to use.
If you are using a shaper and buying off the shelf tooling you get a compromise. High speed steel will be sharper at first, brazed carbide less sharp and less desirable geometry due to the limitations of the type of carbide they have to use to be able to braze it. Inserted tooling is generally available in at least 4 different grades. The professional tooling companies have a better product for whatever your uses are.