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bleeth
01-29-2005, 05:02 PM
Okay-I'll seperate it to a new thread for the purists.
Paco-It looks great-the main thing is does the profile match a particular molding or did you wing it?
If you are going to make curved moldings for contractors then they are very likely buying stock extrusions for the rest and your service will need to match the profiles so therefore:

Gene or others-How do you go about efficiently profiling a contractor supplied molding?

Dave

Brady Watson
01-29-2005, 05:22 PM
You can either scribe the profile in on a piece of paper and scan it in on a flatbed scanner, trace with vectors and extrude using any # of programs out there...

or use a Picza and scan a few lines to get the profile ~ then extrude in the same fashion. I would imagine that you could also use the SB probe, but it won't get into every nook and cranny with the 1/16" stylus. Then again, neither will your bit.

I have scibed profiles attached to the wall of a victorian house (at the floor....slip paper under molding and trace with fine pencil), vectorized the tracing, and swept the profile in Rhino. There you go. You can sweep it along a straight line or a curve just as easily.

-Brady

fleinbach
01-29-2005, 05:42 PM
Brady

After sweeping in Rhino can you follow the swept profile maintaning the same Z height throughout each pass? Or do you run it as a 3D file

bleeth
01-29-2005, 05:44 PM
Thanks Brady: That is pretty much what I was thinking. I know a lot of the molding manufacturers also print and/or post full size drawings of their moldings as well and although my software is Artcam 7 the sweeping tools are probably similar to Rhino.


Dave

Brady Watson
01-29-2005, 05:47 PM
Yes Frank....It's a 3D toolpath, unless of course you want to waste hours and hours making it a 2D one with various bit geometries etc, lots of coffee and migranes


-Brady

bleeth
01-29-2005, 06:04 PM
Quite a few moldings have hard inside corners which would indicate a flat bottom bit with a toolpath strategy using really miniature stepover. That could mean some heavy machine time for a very normal clerestory window arch that could easily need to be 6 feet wide. What do you suggest in that regard?

Dave

paco
01-29-2005, 06:18 PM
Brady,
I might ease all this soon... with a single cup and a smile!

Dave,
not e-v-e-r-y moulding could/will be machine but many...

Both,
still, "limited" to circular arch (did'nt fix the oval path)... but from various openning/spawn... and not limited to only ball end tool bit... I plan on having a demo soon to show; a real part...

I would add that this "problem" with oval path to extrude can be viewed as another option/possibility...

Brady Watson
01-29-2005, 08:00 PM
Dave,
Since you have ArtCAM you can use a larger bit, say 1/2" ballnose to machine the entire molding, then go back in with a smaller bit, machining only the areas that you define. You most likely don't need to do a roughing pass with a 1/2" ball. This strategy would give you the most time effective method of finishing, plus the ability to machine those finer areas that the 1/2" bit can't get WITHOUT rastering over the entire thing again with the smaller bit.

-Brady

fleinbach
01-29-2005, 08:46 PM
Thanks Brady, that's what I thought. I tried to convay this in the other thread where this all started. that Artcam will not follow a swept profile while maintaining the same Z height, but instead does it at some tangen to the swept path. What Paco is working on to create swept profiles while following the swept curves is something that should be capable in a program like Artcam. It is not a perfect solution to createing trims in arcs or any shape you might desire, due to some trims tight recesses and flat inside corners. But it would allow profiles with sweeping curves being cut faster and cleaner then 3D currently does.

bleeth
01-29-2005, 10:13 PM
Brady-Makes sense to me. Since it's all about producing for profit and hence efficiency in my mind I've been thinking about the "big wheel lathe" system that I have seen producers of arch moldings who specialize in them use using what amounts to the toolpath scheme that Frank is wanting to make our software do. For me it gets down to "yes we can do it but it would be better if we could cut circumferences with a nice sharp v bit with a narrow shank and a sharp angle!!"
Does this mean "You can't always get what you want but if you try hard you can get what you need"? In general the idea of using the bot to produce arch molding sounds like a nice little bread and butter complimentary routine that may underutilize a PRT and Artcam or Rhino and vector but can earn some decent $ without major relief work may end up more time consuming and complicated than it appears on first examination. Or am I getting too close to the trees to see the forest? Gene is right-this is a great subject.

Dave

woody
01-29-2005, 10:36 PM
I make curved crown every day. I use a 2.5D program, it’s like sweeping a profile, you pick your profile then your path and BAM, you got your tool path. You can use the pocket profile that will take layers at a time. I precut on the bandsaw and cut within .005 of my finish size.


img src="http://syntheticgraphics.com/cv/cv_images/curvedcrown1.jpg"

img src="http://syntheticgraphics.com/cv/cv_images/curvedcrown2.jpg"

garyb
01-29-2005, 11:58 PM
Sorry Frank, I missed what you was getting at but I see Brady got the answer you was looking for.

fleinbach
01-30-2005, 07:06 AM
Scott

What program do you use? Off course I could see being able to produce a swept crown using a 2.5D method due to all faces being perpindicular to the bit axis. In fact it could theoreticly be cut with a bit cut to the crowns profile. Off course you would have to take very shallow passes.
The question is will your program cut a profile simular to the one located in the thread where this all began located here http://www.talkshopbot.com/forum/messages/2/6137.html?1107010033
You will have to scroll down to see some of Paco's drawings.

geneM (Unregistered Guest)
01-30-2005, 09:36 AM
WOW,
left work around 4 on sat, came back sunday and found all of this!

I have been doing these for a couple years and cangive all of you guys some GREAT advice!

When the client calls, get the profile, window size(H x W)and the window model#.
ALL window manufacturers have web sites with online catalogs.

First, the profiles are almost always in a catalog.
these I scan on a flatbed scanner.
When they are not... I cut a 1/4" peice and scan that on the flat bed scanner.
either way...open the file as "create model from image" in ARTCAM Pro.
reset the releif and draw the profile as an open vector.
save this.

now, as far as the shape goes, go to the manufacturers site and copy and paste the window picture into artcam.
reduce it to 2 colors, then create the vectors from the bitmap image.
after that... resize to the supplied dimensions from the client( often you will need to adjust about an eigth for the reveal)

use the extrude function to create the molding releif.

check both the profile and the shape closely as a simulation.
these may need to be cleaned up.

ARTCAm users who spend time on their forum will see downlaodable videos for this process.
generously donated by Mitch the PA. shopteacher.

as far as using a ball end mill to cut them and not having a sharp "crease"...most often the client never notices.
arched and eliptical windows areoften above eye level.
Builders are not too particular(some are), the sharpness can be sanded in by hand with some 150 grit wrapped around a cabinet scraper.

MAype I am "copping out"
but Ted told me way back when ..."CNC machines make lousy table saws"
the jist of that is...When you need to do something simple...do it simple.
let the router get you as close as it can.then improvise.

One more thing,
all this talk of changing bits. Unless the CNC changes the bit for you, you are opening yourself up to"human error"
95% of our machining is with the 1/8 taperball.
so much in fact that 4 out of 5 routers in our shop have probobly never seen a different bit
( maybe a little of an exageration)
but seriously... to change the bit and then re zero can often lead to slight errors.
combine that with the bowing and cupping of many species of wood and you could possible fill your garbage cans with more products than your shelves.

finally, Please remember, when desinging these moldings, the angle at which the molding sits when installed is not always the way a millwork shop would run it thru the W&H molder.

for instance, we are currently cutting bar rail for a Humongous job.
the 150' of straight rail goes thru the molder as a 8/4 x 6. but then rests on the surface at a 15 degree angle. the corresponding rounded corners must be cut from 10/4 x 10" stock to accomodate for this 15 degree slope. the same will hold true for most crowns, panel molds and the like.

I hope I am helping, given that most levels of experience are varied, I always try to post for the middle of the pack.

thanks
Gene Marshall

bleeth
01-30-2005, 09:36 AM
Good Morning Frank: in Artcam by defining your toolpath as machining selected vectors then you will end up cutting your molding along z level axis. It's been interesting playing with a new strategy. I hope the small jpg shows the cutting lines clearly enough. This would be a first pass with a 1/2" ball nose

Dave



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bleeth
01-30-2005, 09:48 AM
Wow Gene: simultaneous posts!! I found from someones suggestion elsewhere a simple line drawing to vector converter available as freeware that I downloaded last night that may shortcut the shape to vector process even more. See
http://wintopo.com/

Dave

garyb
01-30-2005, 11:15 AM
Gene, nice synopsis. My question is how are you handling your blanks? I presume you have a bending table for your solid woods.

geneM (Unregistered Guest)
01-30-2005, 02:55 PM
Gary,
good question
I do not steam bend.
I make latteral glue ups.
while in artcam I draw a rectangle to represent a portion of the stock i intend to cut. then copy and paste it over the digital molding.
to rotate I suggest using the transform vectors feature.
maybe I am over simpifying this.
but the idea is to be able to quickly cut 1 offs.

I like to use these rectangles to give me a layout for blocks of material that will contain the molding within its borders.
to that end... create vectors that represent the outside of the molding and cut them on your material to make sure you have assembled them the way you should have.

another way to get the blank is to glue strips, about 1/8 thick together into a form. this is how ANDERSEN WINDOWS makes theirs. I have tried this and the down side seems to be that you would need to have a form for each window, as well as the mess glueing all that up.

the first way seems to be the easiest.
I glue them up right on the table with west system 5 minute epoxy. using wood screws instead of clamps to provide tension.

however, no two ways about it...
if you need to make a bunch of arched moldings.
the molding machine is more efficient.
but when you add the cost of cutters to a single arch. most clients will be taken back.
our molding machine runs about 5 seconds per foot.

but this procedure is a good money maker for short runs.
and even if you use the molding machine, the cnc will cut the shape for use in the molding machine more efficiently than a bandsaw or jigsaw ever could

cheers,
gene marshall

geneM (Unregistered Guest)
01-30-2005, 03:01 PM
one more thing...
installation trimmers like to have a straight drop on the bottom of the moldings.
the key to this is your drive rail should be an arch, with short vertical lines added to the start and end.

by adding these "drops" the trimmer can miter the molding into the horizontal peice quickly.

cheers
gene

Brady Watson
01-30-2005, 03:17 PM
Gene,
Good point: "combine that with the bowing and cupping of many species of wood and you could possible fill your garbage cans with more products than your shelves. "

When cutting molding on the bot, it will invariably want to bow up or cup. I strongly suggest using vacuum or some other means to keep the material flat. AND if you do change bits, make sure that you remember where you zeroed your bit the 1st time ~ better yet, keep a block of material on the piece where you can do this. Zero the bit, move the bit to your zero-plate height and use it as a feeler gauge to be sure that you are exactly where you need to be in Z.

-Brady

bleeth
01-30-2005, 06:17 PM
Gene: If I understand you correctly you are generally using the system of end gluing blocks that end up cut as regular trapezoids possibly at (for example) 11.25 degrees for 22.5 degree shapes and using 5 minute epox. For this system I am in the habit of using a biscuit or two where it won't show and Titebond I or II. I'm sure you don't have much joint failure with your method or you wouldn't use it but it does seem a little "light" for end gluing. One of Bill Y's bot generated step scarfs, a traditional half-lap, or even a quick route with a glue joint bit would seem to me to give it a whole lot more structural integrity as the piece goes through all the moving, shipping, and handleing before it is finally installed on someones wall. What do you think?

Dave

geneM (Unregistered Guest)
01-31-2005, 08:21 AM
Dave,
Yes to both...

I got a finger joint bit from TWC at the last show.
tried it and although it was definitely stronger, the setup added cost to the part.
the biscuits are a great idea and i have added them after the fact.
I would have trouble plotting the location of the biscuit before the cut.
the epoxy is pretty f'n strong.
Maybe some others who are following this thread would weigh in on this issue.

like I said before... the methods i am using are about a cost effective way to push a single peice thru production.
I know that there are better ways, more secure jointery, more accurate drawing techniques.
IN FACT... better woodworkers than me, out there.

brady, how ya been,
we do not use vacuum hold downs
we most often make our blanks larger than the model and screw to the plywood table.
pretty unsofisticated for a CNC shop, but hey, works for me.
also, because the bits we use are Tin. coated, the Z-zero plate is useless.
so I would have to do all zeroing by eye. Good luck with that.
my theory so far, get all you can out of the first run, after that...improvise.
sometimes I struggle...not too often.
vast majority. out the door within a 2 week turn around
builders love that.

cheers
gene marshall

rookie432
01-31-2005, 04:27 PM
Gene,

Great info. Nice to see you in the forum again.
Just wanted to say hi and let you know I check your website every few months and your 5 ladies piece is pretty impressive.

Hope to hear more from you.

Bill Jarvis

garyb
01-31-2005, 04:37 PM
Gene, interesting method for your blanks. I guess it would also give you the advantage of creating a radius profile larger than your table.
We use the same method for medellion borders but they have a backer and become a one piece unit therefore not subjected to installation movement.
Never dreamed of doing it with radius mouldings.
Here, the blanks for arch mouldings and radius bases are 1/8" strip glue ups formed on the bending table, then shoved through the moulder.

Frank, now that I'm thinking 1/2 way straight today. What I stated in other thread was

"If machining a relief you can select an offset strategy and cut in climb or conventional direction and you can select a starting point of the inside (center point) or outside edge"

This method is cutting your tool path along the Z level axis meaning the offset strategy follows the profile of the relief, then you also have the option to cut in a conventional direction or a climbing direction and you can start on the outside edge or the center or the relief.
Just as Dave's photo above, but to answer the burning question yes Artcam will machine along the Z level axis on a radius profile.

Brady Watson
01-31-2005, 04:53 PM
Gene,
Good!...we've been busy!

Hey good mention of the coatings on the bits and the fact that the z-zero plate doesn't work with it!!!

I just did a run of 2000 carbon fiber parts, and the diamond coated bits were the same way. Luckily my intuition was right...and I tested the plate on the bit 1st before wasting a $50 bit!

Back to the method we used before there was a z-zero plate ~ a steady hand on the controls and a piece of paper. I find that DOS is easier to work with than Windows because the keys/response are too ham-fisted on the Windows version.

-Brady

jf_allie
01-31-2005, 09:15 PM
Hey guys,

I have read you can keep precompressed wood for a while before you bend it... It might be way to make your stock before machining. Also, I wonder if it could be machined before bending...or before precompression.

http://www.compwood.dk/
http://www.bethelfurniturestock.com/news_1.html
http://www.iswonline.com/wwp/200107/bethel.htm

jf

P.S. Paco there is a company that makes precompressed wood in Quebec as well.

bleeth
01-31-2005, 10:11 PM
Jean-Francois: This is a new one on me and I LOVE IT. The imagination goes wild with fantastic designs. Salvidor Dali in three dimensions. You guys can make moldings out of it-I'm building clocks with backward running hands.

Dave

Brady Watson
02-01-2005, 12:16 AM
Yeah, pretty cool!

I saw this a while ago...and dropped it because the stock wasn't available in the US...Looks like it's more common now.

-Brady

geneM (Unregistered Guest)
02-01-2005, 07:53 AM
Jean-Francois,
great link, although once again the cost and time factors may turn off the average builder.
these guys are cheap, I know , I'm one.
But all in all, I agree with dave, My imagionation runs wild.

maybe we should try to get some and play with it.

Bill, How ya been, thanks for the compliments.
I get a little worried that the work will dry up.
then the phone rings and I get worried I wont get any days off.

LOL

Paco , have you tried this bendy wood, saw your site, great stuff.

Dave, tried to look up your site, couldn't.
please call the office when you have a chance,
got some questions about FLA.
732-899-4458
thanks
gene marshall

gerald_d
02-01-2005, 08:26 AM
Even here in Darkest Africa I have played with that stuff about 5 years ago. Was involved with a guy who wanted to produce the flexible wood here for the local boat building industry. Some snags I remember is that the timber that goes into the machine must have a perfect grain (no knots, etc.) and must be "green", (not commercially dried). In other words, you need access to still growing trees - commercially dried stuff from timber merchants is useless for this process.

The machine presses the wood from 3 directions - in thickness and in width, as well as in length. It is a fairly complex pressing process.

After the wood has been bent and fully cured (dried), it is not quite as strong as wood where the cells have not been burst.

And that is about all that I can remember. It never took off here - the steam route is still the well-beaten path.

paco
02-01-2005, 11:05 PM
J-F & Gene,
nope; I did'nt tryed that yet. I browsed the links and look interesting though I do not have a use for now...

paco
02-01-2005, 11:18 PM
By the way, I'm currently working on a new previewer for SBP file... with p'etty good rendering...

2624

2625

jf_allie
02-02-2005, 08:27 AM
Hey Paco,

Is this a strait piece of Polyethylene foam glued in a round?... cause that's exactly what I had in mind when I mentioned the precompressed wood i.e. machine it strait then bend... especialy when the end product is out of touch and painted.

gerald_d
02-02-2005, 08:41 AM
There is no way that you would bend straight foam into a circle and not see the joint.

garyb
02-02-2005, 06:34 PM
Jean-Francois
Interesting link, there's a number of little projects I can see using the precompressed wood, but I would suspect you would be very limited with profiles.
I mean how much distortion will your profile be subjected to in bending?

jf_allie
02-02-2005, 09:31 PM
Gerald,
Please explain the problem you see with the joint, Is it the darn glue line again? I'm curious.

Garyb,
Yes indeed that is the question...but also how much shrinking after it's cooked? Maybe it's not possible to machine before... I was after all speculating...

beacon14
02-02-2005, 09:56 PM
I would be surprised if you could mill it before bending for two reasons: it's wet, and it's not stiff. (For those who didn't read the linked web sites, the product is processed at 20% MC and must not be allowed to dry before bending.) Even if you could figure out how to push it past a cutter while keeping it perfectly ridgid, I'd have to wonder how the cutter will perform in wet, spongy wood and what kind of surface you'll end up with when it dries. The picture that comes to my mind involves lots of sanding after it dries.

paco
02-02-2005, 10:23 PM
J-F,
no... it's a 2D profile "extruded" along a circle path; the program read the 2D profile and machine it's shape along a circular path. Here the 2D profile that I used to "extrude"... The part above is 14" outside diameter and about 0.625" thick.


2626
Each path (or pass) of this 3D type part is Z fixed height, which make the machining process quite fast and clean.
...but you can't see this on the rendered preview above with the textures and shadowing I added! 8-)

gerald_d
02-03-2005, 12:41 AM
J-F, straighten out a paperclip and then bend it to make a circle. You will see that you can't bend the last 8mm at the two ends without using a lot of force. With a piece of foam as wide as Paco showed, bent in a circle of such a tight diameter (would be a very soft foam), he would have been lucky to get a "water drop" shape. If he had some super special foam, that would hold its shape after bending without springing back, he could have used a piece that is too long, and trim the straight tips after bending, but then it is used like a wound spring and the whole thing doesn't lie flat afterwards. Bending perfect circles is extremely difficult. Even bending half-circles is difficult - you tend to get parabolic curves, and not instant transitions from straight to circular.

fleinbach
02-03-2005, 07:11 AM
Paco

What you have done is fantastic. My question about weather or not Artcam can accomplish this the way you and I and probably many others are looking for has been answered several times but I'm still not sure it will do it this way. But even if it can it is at a considerable cost if this was a persons main objective. That is to have a simple program that can easily be set to follow any vector path. You seem to have gotten the basics, now all we need to do is work it into an easily setable program to be added to the tool extras in the shopbot software. I believe you mentioned you would like to obtain help to get it to that point. If you would like I could ask my son if he would write the program. He is a programer and owns a company that writes software for Microsoft
( I'm not sure if that's an attribute or not
)

garyb
02-03-2005, 08:12 AM
Hey Frank, if you would like to send me a drawing of the profile you want, and the arc you want it extruded on, I will tool path it in ArtCam and send to you to trial cut.

I would have to say if this is a persons main objective for the program then Artcam would be a waste of money to them, due to the fact that Artcam does so much more and unless you utilize the benifits of the program then your not getting you monies worth. just my 2 cents.

Jean-Francois and David, some good points. The big advantage I see of this system is to eliminate curved glue ups, I mean if you can just bend this to your radius, dry then run through the moulder think of the possible labor savings in time.

jf_allie
02-03-2005, 08:50 AM
Guys, I'm realy surprised to learn that there isn't a sort of "sweep along path" raster strategie in ArtCam !!!

SO, Paco is there a Project Wizard "coming to a neighbourhood near you" soon?

I remember clearly, Bill & Ted mentioning that at this stage of the Project Wizard system, if you could come up with a part file, they would help you with the interface part.

You could make it so that the ShopBotter can upload ANY profile, or, simply provide a choice of profiles with a choice of path shapes (circle, elipse, arcs...)

David, you're probably right about the precompressed wood, but I think it might still be usefull as curved stock. In any case, the proof is in the pudding as they say. The company mentioned in the article might already have tried it.

Gerald, What if there is a groove at the bottom of the profile allowing you to glue it on a simple, sheep,flat wood frame?

paco
02-03-2005, 08:58 AM
I am in NO WAY trying to compete with ANY high end softwares; I am just discovering programming and having A LOT of fun (until my eyes burn in the middle of the night...). What I've showed to all of you so far is a part of what can be done with the SB code; yes, only the SB code! When I get to master another code language it might just speed up the process and probably enhance the possibilities...
I tend to assume that ArtCAM PRO can do this kind of thing (and MUCH MORE); I would be quite decived if I were to discover that it cannot!...

Frank,
thanks you very much for the offer but I'm not really looking for someone else having the fun I'm looking for... my invitation was to thoses who might want to team work on similar projects, share what they have created so far or suggest solutions to problems I submited like some have did since... so, if programming is something that get you excited and your looking for to use this knowledge to create programs to enhance the use of your tool, then you might want to consider contacting me!!

paco
02-03-2005, 09:08 AM
J-F,
both Ted and Bill have already helped me alot in some of my projects. I am VERY thankful for their kind advices and hints...

The circle/arc extrusion program I've wrote allow to choose from the 2D profile of your choice and to enter different values to define the resulting finished part. So this is a two steps process; 2D CAD designing of a profile and the "extrusion" of it along a circle/arc path...

jf_allie
02-03-2005, 02:02 PM
Paco (and everyone interested in programming),

See my post about GUI4CLI in the Developers area.

beacon14
12-03-2005, 06:47 PM
I could use some help with this puzzle. I am limited to PartWizard, DesignCad (2D and 3D) and ShopBot. I am trying to figure out how I can machine this shape in varying lengths.

2627
The workpiece shown is 15" wide x 3.65" high by 20" long but I may need to make some 62" long as well.
Using constant Z height "sweeps" as the bit follows the contour should work fine but how do I get from the drawn curve to the ShopBot file? If it means more software I'd be open to that as I am keen to start exploring 3D work but this is on a tight timeframe so I might need some help just to get this project done.
Thanks all

paco
12-03-2005, 08:18 PM
Formatting ErrorThe formatting code png_alreadyuploaded_t does not exist or cannot be used in this context.

paco
12-03-2005, 08:19 PM
OH C-O-M-O-N!


2628

paco
12-03-2005, 08:25 PM
Hey David!

I've been doing this on a few occasion with custom moulding in foams using both ball end bit, V bit AND "straight slot bit"...

Here the SBP code for you (anybody) to have a look at; but you may need some help for "feeding" it with a "profile path".




2629 (0.7 k)


2630 (0.6 k)

At the time I was working on this (2004-2005 winter), I was using PW to create curve/profile path to follow... Let me gather the informations and I should be back with more complete details about the use of this parametric code... I must say that it's not user friendly, but it's doing what it's supposed to.

See...


2631


2632

I just wish I would have the time to work more on the "curved moulging project"; got to make money first... on the other hand I know some of you have been trying too; maybe some could chime in if they got anything better or different...

By the way, Morris Dovey deserve credit on this little code!

One other thing that I'm thinking of; I've doing similar stuff with RHINO and MeshCAM; both which may do even more than straight custom moulding...

See...


2633

bleeth
12-03-2005, 09:23 PM
David:
You have mail.

Dave

benchmark
12-04-2005, 04:14 AM
David

Send me some dimensional details and I will create a shopbot file for you...I can do curved if you need them

Regards

Paul

beacon14
12-10-2005, 11:05 PM
Once again the forum comes through - Dave R and Paul have been unbelievably helpful - I made a sample from the client's drawings before ever seeing the parts he was having made and shipped across the country. They took one look at the sample and gave me the job.

This is one part of a high-tech (i.e. $$$$$) speaker column. If all goes well I'll be posting pics of the finished product next week.


2634

2635

2636

jhicks
12-11-2005, 10:18 AM
WOW, what interesting stuff. I also make curved molding but dont use any of the techniques described so I'm wondering how my method compares. We have a woodmaster molder/planer so with many contractors who use paint grade materials we take a sheet of 3/4" Trupan, lay out up from 7 to 14 arches per sheet depending on their size and how they nest, cut the radius or eyebrow out with an O-Flute, then feed through the arched jig on our molder. Time to process is about 5 minutes on a cad drawing, maybe 5 minutes to cut, and 5 to 10 to profile on the molder. Admittedly the knife costs about $50.00/ inch in width but with a only one knife required and a 20 minute process plus a couple minutes to clean up the fuzz, the prices justify the knife as many reuse on multiple projects.
We also leave 2 to 3 inches of extra material at the ends for finish carpenters to trim in and it requires 2, 1/2 rounds for 1 full round but that hasn't been any problem. For other real wood we also join at 22.5 degrees, finger join, and cut the same way from wide enough stock to create the arch or eyebrow.
How much time does it take to run these bot generated arches? I know the planer knives give a perfect reproduction and don't have the sharp corner issues so just wondering how you guys match conventional patterns like colonial or victorian trim profiles?
2637

kr_fitz
12-11-2005, 02:27 PM
Jerry,
My former employer used to use the same method as you. Then in 2002 he bought a PRT96 and we began experimenting with it to make the circle top moldings. However, we just used the bot to cut the arc, and then they processed it the old way using a jig and a shaper. It was a pain to get everything aligned and held down (no vacuum) on the ShopBot. I researched the use of vacuum pucks and the use of a laser to spot the pucks in the right place. It would have worked, but the company went under before we could try it. Bill Young wrote a custom circle top window plugin for the ShopBot software that worked very well as it eliminated all the cad layout.

kr_fitz
12-11-2005, 02:35 PM
Jerry, I didn't directly answer your question, did I? If you use Bill Youngs plugin, and use vacuum pucks and a laser, it would take just a few minutes to fixture and cut each arch from the glued-up blank. I think it will be more cost-effective to put the profile on with your shaper.

paco
12-19-2005, 12:55 PM
I've made up a quick tutorial about the Straight extrusion molding for a couple fellow Botters that contacted me recently... it's available to whom contact me by e-mail... all zipped with examples...

paco
12-20-2005, 09:16 PM
Hi Carl!

reply to this message please; seem there is a problem sending you the zipped file...

Paco

paco
12-20-2005, 09:18 PM
To all how have asked for the tutorial (about 20); please, remember that I would like some feedback about it... please...

Thanks!

gene
12-23-2005, 10:09 AM
Paco,
How can i look at the tutorial and what type of software are you using?
Thanks Gene

paco
12-23-2005, 10:34 AM
Gene,

once unzipped, read the PDF doc. first... PDF are read with Acrobat reader (http://www.adobe.com/products/acrobat/readstep.html).

SBP file are used by the SB3 controler, Art file can be from PW (the one included is from the latest Insignia 3.6c; I've included it just in case), the DXF can be from any CAD software...

cip
01-03-2006, 07:06 AM
I am in the process of test cutting a radius molding. Certain section of the profile have a problem with what I call the sewing machine stitch, an up and down of the Z axis instead of a nice snooth profile cut. I am using ArtCam pro and have tried changing the step over all sorts of ways but the end result is the same. The vertical areas of the profile are the worst with what looks like a gear tooth effect.

Any advice/help would be appreciated.

Mike