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MrUserfriendly
03-04-2007, 03:13 PM
I have made a wooden gear. I scanned an actual gear in photoshop, then outlined the image and blackened the gear. Next, I imported the 2-dimensional image of the gear into a carvewright file. I used material that was .75" thick and 1.75 in wide. I placed this on the end of the board. even though the widths of my board were accurate, I was asked if I want to scale. I had choices of abort or continue with scaling. Even though I did not
want to scale, I continued anyway because the gear will still work OK if it is a little bit smaller.


I told it to carve .700" deep. It carved a gear, however, the gear is tapered in the thickness direction. I really wanted the gear to be uniform in the thickness direction. Any suggestions on how to keep it even so that I get a uniform gear? Attached is the bmp file that I generated in photoshop.

This is about my 5th or so carving. I think I have the hang of it. I have read a lot of postings of other people. I get the impression that more people use Corel than Photoshop. I find this hard to imagine, unless it is just that Corel is easier to use. I always believed that Photoshop is the Cadillac and Corel is a Chevy. It takes some know-how to use Photoshop. I have used Photoshop well over 13 years. The thought of downgrading to Corel, and having to learn Corel's idiosyncracies is not what I have in mind but I am willing to do so if I can better use my carving machine. Photoshop is the industry standard for the printing industry.

This thread is about making wooden gears, but I also want to know from someone authoritative on an opinion about Photoshop vs Corel. Thank you in advance.

Incidentally, I think the CarveWright is awesome. I have a CNC vertical mill and to me writing a carving in the CarveWright software is much easier than programming in G-code. The Carvewright people have done a good job. I have ordered the scanner and can not wait until it arrives.

cajunpen
03-04-2007, 03:23 PM
If you are used to Photoshop and already have it - then by all means you are ahead of the game. Most of us have gone to Corel because of the price difference AND the learning curve (Corel vs. Photoshop). Both programs will accomplish the same thing.

As for your gear, did you allow for the 3.5" overhang on either end of your actual board size. This keeps your work under the rollers at all times. I suspect that by putting the carving on the end of the board you may have had more pressure on one end, causing the tapering effect.

CallNeg151
03-05-2007, 01:10 AM
I told it to carve .700" deep. It carved a gear, however, the gear is tapered in the thickness direction. I really wanted the gear to be uniform in the thickness direction. Any suggestions on how to keep it even so that I get a uniform gear? Attached is the bmp file that I generated in photoshop.

Hmmm... Here is my guess- I guess that you used the 1/16th inch carving bit. If that is the case, there is no way to avoid the taper, because that is the shape of the bit- it tapers from 1/16th to 1/8th inch.

What you will want to do is use the "Outline Pattern" option to create a vector path around your gear, and then cut the path. Flip the cut, if needed, so that the subtracted material is on the outside of the cut. The cut will be done with the 1/8th inch cutting bit, and will not be tapered.

MrUserfriendly
03-05-2007, 05:46 AM
Prrior to reading your response, I tried using the 1/8" straight bit. It cut fine, however; the hole is oversized and the gear-teeth are pointed instead of
rounded. I will try the "outline pattern" next as you have suggested.

Charles M
03-05-2007, 07:05 AM
I have made one gear (so far) and did it as CallNeg151 suggested: In Designer, outline the pattern, choose Cut Path and flip the cut. The 1/8" bit will be used to cut around the gear and leave about 4 tabs uncut to hold the gear to the rest of the board. Also, you will get better results with a clean PNG or GIF file than with a JPEG and the higher the resolution the better.

Jon Jantz
03-05-2007, 09:26 AM
Mr UserFriendly.... not an authority, but will give you my two pesos. As far as Corel and Photoshop go, you can do very well with Photoshop. The tools you use to tweak a bitmap are pretty basic and either program has way more capability than needed to prepare a bitmap for Designer. There is no need to move over to Corel if you are proficient in Photoshop...

For adding beveling to letters, creating logos, and even making the gear cutouts, it is very beneficial to have a vector program. I design about 90% of my projects in CorelDraw, but I also have Illustrator. Either one will do the same thing, as you again are just using basic tools. Being a Photoshop guru, you would probably prefer Illustrator.

As far as one being a Cadillac and one a Chevy, it's like this. Both programs have way more tools and capabilities than most normal users will ever use, unless you operate the program all day every day. I find Coreldraw's tools more intuitive, and they have evolved faster than Illustrator. But Illustrator is still the preferred program by Graphic Designers.

I am a part of a sign forum that has many of the designers whose signs you see every month in Sign Business, Signs of the Times, and Signcraft. Even among these people it is divided about 50/50 CorelDraw and Illustrator.

So to answer your question in short form: "It doesn't matter." Go with what you are most familiar with and what you can afford.

Edited to add: I'm attaching a quicky sign I'm making this morning. It's for my dad and is his logo. He sells steel buildings, so the beams will be hollowed out like I-beam, with the lettering suspended in the middle. This took me about 15 minutes in Coreldraw, drawing it up from scratch.

CallNeg151
03-05-2007, 10:18 AM
Prrior to reading your response, I tried using the 1/8" straight bit. It cut fine, however; the hole is oversized and the gear-teeth are pointed instead of
rounded. I will try the "outline pattern" next as you have suggested.

Definately. You don't want to cut the gear out in raster mode (sweeping from side to side like a printer), you want to use the cut out or router path tool to actually follow the vector path to cut the gear. The sides will be even, AND it will be many times faster (much less cutting to do).

Just so you can see it, I threw together (under 5 minutes) a board that shows you the steps.

MrUserfriendly
03-05-2007, 03:10 PM
I tried using the 1/8" straight bit and my bit broke in the middle of carving the gear. I have bits on order from over 2 weeks ago that I think are not due for quite a while. I have removed one of the set-screws. The other is not so easy and has some WD-40 soaking it loose. I'll try in a while.

While I am waiting for my bits can anyone tell me where to get a plunge-bit that I can replace inside the holder while I am waiting for my order of bits. At that rate, I will not be able to test the good suggestions for a while. After I remove the second set-screw, I will replace it with a better screw. ALternately, someone please send me a private email if you have a solution for a 1/8" straight bit to lower my waiting time. Thank you in advance.

I know this is on other postingss - but I tried a search and did not find it

CallNeg151
03-05-2007, 05:00 PM
I tried using the 1/8" straight bit and my bit broke in the middle of carving the gear. I have bits on order from over 2 weeks ago that I think are not due for quite a while. I have removed one of the set-screws. The other is not so easy and has some WD-40 soaking it loose. I'll try in a while.

While I am waiting for my bits can anyone tell me where to get a plunge-bit that I can replace inside the holder while I am waiting for my order of bits. At that rate, I will not be able to test the good suggestions for a while. After I remove the second set-screw, I will replace it with a better screw. ALternately, someone please send me a private email if you have a solution for a 1/8" straight bit to lower my waiting time. Thank you in advance.

I know this is on other postingss - but I tried a search and did not find it

I'm sorry to hear about breaking the 1/8th inch bit. I hope it wasn't my sample pattern that killed you. One thing you must do when doing cutouts within 3.5 inches of the edge of a project is select the "keep under rollers" option. If you do not, the board will tend to buckle, and the cutting blade will end up trying to drive through the full width of the board because the cutting passes do not line up perfectly.

Someone else was short a cutter bit, and managed to use a RotoZip bit:
http://www.carvewright.com/forum/showpost.php?p=15439&postcount=10
but found that it was more prone to breakage (but cheap to replace).

Anyway- How to get your bit out of the holder:

The bit is held in by the screws and by loctite. Hold the bit with a pair of pliers, or in a vice, or something so that you can apply some heat to it with a heat gun or something similar. This will melt the loctite a little bit. Remove the retaining screws with the allen wrench. The bit will still be stuck in place. Using a small hammer and punch, you should be able to drive the bit out of the holder by gently tapping the shank end. The holder can then be re-used.

Good luck.

Dan-Woodman
03-05-2007, 09:25 PM
1/8" cutting bits are available at most any mail order woodworking catalog or online.
The problem is they don't cut 1" deep like the carvwright bit. Which now we know why 1" cutting bits ane not available( they break) 1/8" solid carbide is too brittle to cut 1" deep.
An alternative would be to get a 1/8" bit that cts 1/2" deep and cut from both sides.
Pricecutter, Woodline, MLCS, all have 1/8" cutting bits 1/4" shank, 1/2" cutting depth.

John
03-05-2007, 09:49 PM
Woodcraft carries the Whiteside router bits. In fact they have the 1/8" spiral down on sale right now. (Actually all Whiteside bits are on sale right now for 20% off at Woodcraft) The Whiteside part number is RD1600 and the Woodcraft catalog number is 09I17. They have a store in Canton on Ford Rd just west of 275. They also have a store on the north end on Van Dyke in Sterling Heights. Glenn Wing Power Tools on Woodward in Birmingham (I think) may carry Whiteside also. Probably want to give any of these a call to see if they have them in stock before making a special trip.

I have used the RD1600 in my CW without problems. Cutting depth IS limited to 1/2".

John (near Flint, MI)

Kenm810
03-06-2007, 08:00 AM
John

Thanks for the info on the bits, I forgot about Glenn Wing, I drive by there a couple times a month, and Woodcraft on Van Dyke is about 3 miles from my house.

Thanks Again
Ken

MrUserfriendly
03-06-2007, 08:01 AM
Thank you for all the excelent suggestions. While I solve the bit issue, in the meantime, I have been working toward making vector images. I have had Adobe Illustrator and kept up on new versions for the last 13 years - but rarely use Illustrator. I can not use Illustrator as well as Photoshop. However, I called tech support at Adobe and they told me how to easily vectorize my rasterized scan. So, now I am able to vectorize a scanned image.

This leads to a question. I like what was said about using vectorized images because then your cutting time will decrease and less cutting is done to get the same work done. This makes sense as a goal to set. Do I want to vectorize the entire gear as black as can be done in Illlustrator or do I want to just have the two paths ( outline and hole in center)?

One thing is disconcerting about Illustrator. It is touted to be the king of such programs. However, it does not have a history command the way that photoshop does. You can simulate a history command by hitting ctrl-Z many times, but this is not robust. Does Corel have a history command where you can go back many steps earlier in your imaging process? I would be willing to go Corel if it saved me time and effort and this is an important issue to me. It is time spent doing the job. In Photoshop, I frequently use the history command. Also, does Corel have the Rasterizing and Vectorizing all in one package? Thank you in advance.

Charles M
03-06-2007, 08:54 AM
The History in Photoshop is a recent addition. It can only go back a preset amount of steps because it uses a LOT of memory with everything being rasterized. That's why you see the steps and have only one Undo. Illustrator's Undo uses little memory and can go back a LONG way (maybe all the way to the file opening?) but does so in individual steps. If you use a lot of keyboard increment moves with the arrow keys it will take a long time to undo a move but other than that I have always been happy with the way the undo works. I think CorelDraw has the same type of Undo as Illustrator.

MrUserfriendly
03-07-2007, 01:52 PM
From a longevity point of view, especially when using very hard woods, would it be better to use a 1/4" cutter to cut a rasterized pattern? Or even a 1/2 inch cutter? Obviously, this affects inner radii at sharp corners and turns, but for cases without sharp corners would it not be better to use a larger than 1/8" cutter. I am using woods like zebrawood, paduka and other very hard woods. So far I have not used wenge which is much harder yet.

When I use zebrawood, I specify it to be mahogany, since zebrawood is not on the menu. Maybe that is why my bit broke. CW told me that my bits are coming in one month. Do we want to ask CW to include a superslow mode so that the bits will not break on ultra hard woods?

Charles M
03-07-2007, 04:49 PM
Longevity from a standpoint of less likely to break or time to dulling? If you were to use a larger diameter bit for cutouts the RPMs would be too high and I'd guess you would overload the motor. I do like your suggestion about controlling the cut but I think reducing the depth of cut per pass would be better than slowing the feed rate since feed rate, RPM and cutter configuration are all related and too slow feed will result in burning and reduced cutter life.

MrUserfriendly
03-09-2007, 11:27 AM
As mentioned earlier in this thread, my cutting bit broke, It will be about 3 weeks at best before I recieve a new cutting bit. A 1/2" replacement will not work because I am cutting thru 3/4" material.

I have some questions about the cutting operation of the CW machine.

Raster Cutting: When it is cutting a raster image, I assume it is cutting pixel by pixel in a down-cut many times. It is possible that in this mode, it does not cut side-to-side. Is this correct?

I would watch my machine cut, but i can not because my cutting bit is broken.

Vector cutting: I assume in vector mode it is cutting to the shape of the object with less waste. Does it cut in this mode in mostly a sideways cut where the cut is done by the side of the cutter? Or is it a series of many downward-cuts?

I would guess that my bit broke by doing more sideways cuts. Does this sound correct?

Is there a way to control the machine when cutting very hard wood to cut more often in a downward motion to avoid breaking the bit as I have done?

CallNeg151
03-09-2007, 03:08 PM
As mentioned earlier in this thread, my cutting bit broke, It will be about 3 weeks at best before I recieve a new cutting bit. A 1/2" replacement will not work because I am cutting thru 3/4" material.

I have some questions about the cutting operation of the CW machine.

Raster Cutting: When it is cutting a raster image, I assume it is cutting pixel by pixel in a down-cut many times. It is possible that in this mode, it does not cut side-to-side. Is this correct?

I would watch my machine cut, but i can not because my cutting bit is broken.

Vector cutting: I assume in vector mode it is cutting to the shape of the object with less waste. Does it cut in this mode in mostly a sideways cut where the cut is done by the side of the cutter? Or is it a series of many downward-cuts?

I would guess that my bit broke by doing more sideways cuts. Does this sound correct?

Is there a way to control the machine when cutting very hard wood to cut more often in a downward motion to avoid breaking the bit as I have done?

Carving- The machine prints much like a dot-matrix or ink-jet printer, moving the carving head side to side, removing .005" with each pass in Best mode.

Cut-out: The bit plunges into the wood a certain depth, and then follows the raster path, cutting out with the side of the bit. Once it completes the path, it cuts out a little deeper the next time, and keeps repeating. On 3/4" of material, it makes four or five passes (can't remember), with the final path leaving a few small tabs to hold the workpiece in place.

It is really important that the workpiece stay under the rollers when doing a cutout operation. If it does not, the bit is very prone to break because a noticable "stepping" will occur due to warpage of the wood. This means that the deeper cuts do not line up with the less deep cuts, and as a result the cutting blade is passing through the full depth of the material.

Hope this helps.

MrUserfriendly
03-09-2007, 04:40 PM
When we enter a wood such as Mahogany or Pine, is this a color-viewing aid or is this wood type used in changing how fast or slow the machine cuts, the feed-rates, the depths-of-cut, spindle speed, etc.?

HandTurnedMaple
03-09-2007, 04:42 PM
I think its just for looks, to compare even though those are not the favored woods for the majority of users. If it asked at upload what wood we want to use I would be inclined to think otherwise.

CallNeg151
03-09-2007, 04:45 PM
I think its just for looks, to compare even though those are not the favored woods for the majority of users. If it asked at upload what wood we want to use I would be inclined to think otherwise.

I'm pretty sure it's for looks only. Indeed, I remember reading somewhere in the forum of people creating their own textures to better see their patterns.

I think a "slow down" option might be a useful feature in later versions. One of the greatest features of the Designer software is that you don't need to know about programming CNC routers to get good results. The downside is, of course, the limited range of materials that the unit can handle. A single "Slow Down" option for really hard woods, like you are using, might be a good way of preserving the simplicity of the program, but allowing for a wider range of woods to be used.

pkunk
03-09-2007, 05:04 PM
Really not necessary to slow it down. I've cut some of the hardest woods readily available with no bogging down of the cut motor. Over 120 hours on the cut motor and no problems. The heaviest cutting I've encountered is a really deep, bold centerline text with a 60° v-groove, and the machine would slow down a little but always survived.

CallNeg151
03-09-2007, 05:14 PM
Really not necessary to slow it down. I've cut some of the hardest woods readily available with no bogging down of the cut motor. Over 120 hours on the cut motor and no problems. The heaviest cutting I've encountered is a really deep, bold centerline text with a 60° v-groove, and the machine would slow down a little but always survived.

Although I've been lucky enough to have no real problems I'm just wondering about the life of the 1/8th inch cutting bit for cutouts, and was just speculating that slowing down the X-Y drive might reduce the pressure on the bit as it cuts through the wood, and that this, in turn, might reduce the incident of breakage. Whether this is of any use would depend on how common it is for that bit to break doing cutouts.

pkunk
03-09-2007, 05:32 PM
Although I've been lucky enough to have no real problems I'm just wondering about the life of the 1/8th inch cutting bit for cutouts, and was just speculating that slowing down the X-Y drive might reduce the pressure on the bit as it cuts through the wood, and that this, in turn, might reduce the incident of breakage. Whether this is of any use would depend on how common it is for that bit to break doing cutouts.
I've done alot of cutouts and only broke 1 bit. That was on the old flex shaft and it lost contact with the cutmotor and got drug across the board without spinning.

Dan-Woodman
03-09-2007, 07:43 PM
Hey PK
I wonder when you choose "best" if it takes a smaller bite with the cutting bit as it does with the carving bit.
I mean like the carving bit takes .006 or so , does the cutting bit take smaller depths of cut in best quality setting?

pkunk
03-09-2007, 08:19 PM
Hey PK
I wonder when you choose "best" if it takes a smaller bite with the cutting bit as it does with the carving bit.
I mean like the carving bit takes .006 or so , does the cutting bit take smaller depths of cut in best quality setting?
Good question, Dan. I don't know, I doubt it though. I don't usually watch my machine work. We're not supposed to leave it unattended but I do. Usually it does it's thing after I'm done in the shop for the day. I visit it briefly periodically to make sure it is working, brew in hand.

HandTurnedMaple
03-09-2007, 10:08 PM
I don't think it makes a difference. I don't have my controller on hand right now. Someone make just a simple circle with the cut out and then upload it. If changing the quality changes the time then you are probably correct. But if the time remains the same then the "quality" has no effect on the cutting.

MrUserfriendly
03-12-2007, 03:21 PM
My carving bit arrived way before the projected date of arrival. Thank you CarveWright.

john B
03-15-2007, 12:42 AM
this is the first attempt at cutting a gear, I also cut a rack for a rack and pinion set up for a project along with a bolt made from another tool i had.
I just wanted to try to make it work if i could. this is the first piece i cut with the cut path i did and i was worried about the 1/8 bit also butwhen the cw started to cut it did it in 4 stepd shallow cuts, i assumed it was the way it is supposed to work. but all worked out and no broken bit.
i still have alot to learn and little time for experimenting with it and corel.

MrUserfriendly
03-15-2007, 08:09 AM
John,

Your gear looks real good. Could you send me a copy of your Designer
file? Thanx.


Mr. UserFriendly

Gman_Ind
03-16-2007, 03:41 PM
I have a DXF file of a plastic gear I make. I have a compucarve ordered and will want to make a few with the compucarve . The software will import a dXF right??
it is 1/2" thick so it should cut right through it with a 1/4" endmill. err router bit.
I think I will want to nest this instead of milling from a small blank I think this will be the main material and setup saving feature. Now I make a 2x2 blank, 1/4 center drill then bolt it to a fixture for conventional CNC cutting, With this I will be able to layout the nested parts on the material strip. Is there any known issues feeding Delrin in the machine?
Thanks!

Charles M
03-16-2007, 04:11 PM
Mike,

You cannot import a DXF file. The only way to get a shape into the software is to either create it in Designer or make a raster gray scale image and import it. If you do the image at high resolution with transparent background you can outline it in Designer and choose Cut Path to cut out the shape. Nesting the shape will have to be done by hand. I don't have any experience with cutting plastics yet.

BTW, it cuts out with the 1/8" bit which is supplied with the machine.

Digitalwoodshop
03-16-2007, 08:31 PM
Delrin is similar to PVC board. I cut PVC board (komo brand) with no problem. Give it a try and let us know.

I have some engravers plastic I want to try.

I wonder if doing it in best mode takes smaller bites??

Need to try that.

AL

Gman_Ind
03-19-2007, 09:43 AM
I received the machine and it died right away, and I was not cutting plastic yet.
Sarge stated that using best mode on the machine created a smoother carving. so that would indicate it is doing a closer interpolation (with smaller chords) of the curves it should make no diff on a depth of cut or chip load. and no diff. on a straight line. I was taught (years ago) that a cnc converts arcs into chords and the shorter the chords the slower it runs and the closer to the actual shape the bit travels.
The best test of the speed and subsequent chip load would be to have the machine cut a staight line deep in multiple passes. do one on normal and one in best. time both and see if it takes longer on the best. if it does then it would be cutting at a lower feed/chip load.
I cannot evev perform this simple test as Mine is DOA.
A circle would not be the best test as it may be just dropping the chord length. a good test of this might be to have a large circle cutout in draft then another in best, look for visible flat spots (the actual chords) on the draft workpiece.
Disclaimer: I am using info I was taught in college back in 1988 about CNC milling. feel free to correct me or share your results!

Charles M
03-19-2007, 12:41 PM
Mike,

IIRC, the Draft, Normal and Best modes have no effect on vectored cutting, only on rasters. This is based on changing that setting before uploading and it did not change the estimated time to completion. So I don't think you can change the feed rates/bit speeds from the built-in machine settings.

MrUserfriendly
03-20-2007, 03:37 PM
In response #3 of this thread, CallNeg151 gave a good answer with details on how to cut the gear. I tried doing the following steps.

1. Import gear
2. Place gear on wood.
3. Tools - "Outline Pattern" to create a vector path around the gear.
4. Tools - "Cut Path"
5. Flip the cut, if needed.

In my attempt to do the above, when I got to the "cut path" step, there was no option to "cut path". Is this because my selection of "outline pattern" included the hole in the gear as well. In any event, I am currently unable to get to this step 4. Any suggestions by anyone would be appreciated.

Charles M
03-20-2007, 03:41 PM
Did it outline the gear and the hole in the middle with separate paths? If so, you just need to select the outer path and click the Cut Path. You could even select the hole path first and delete it if you like. If this doesn't work try zooming in close and see if the path around the gear is complete or if it is broken into segments. It will have to be complete to work.