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Duncan
03-28-2014, 09:24 PM
Do the two pieces holding my project have to be the same thickness as my project. For example if my final board measurement is 10" long by 10" wide by 3/4" high and I cut the board 10.25" by 10.25" by 3/4" and center under the rollers will there be a problem if the two end pieces holding my project are 4" by 11" by 1"?

Duncan

eelamb
03-28-2014, 09:34 PM
The thickness is important that they be the same, and the width needs to be the same too, in this case.

fwharris
03-28-2014, 09:45 PM
Eddie is right, the top surfaces of the board and sled should be the same. You can get away with having the carving board less than the sled thickness by having the bit touch on the board when it is doing the "finding surface". What you need to make sure of is that the board/sled top surface is the same thickness for the full piece.

Duncan
03-28-2014, 10:44 PM
Thanks for your help. Since I am planing rough lumber I was hoping I could get away with the end pieces not having to be the exact thickness of the project pieces. It would eliminate the need for multiple end support pieces as each project will have different thicknesses.


Duncan

fwharris
03-28-2014, 11:43 PM
Thanks for your help. Since I am planing rough lumber I was hoping I could get away with the end pieces not having to be the exact thickness of the project pieces. It would eliminate the need for multiple end support pieces as each project will have different thicknesses.


Duncan

How much difference is there between your thickest and thinnest pieces? If not to much you could set your sled up for the thickest boards. When carving the thinner ones you would have to jog to the board surface during the "finding surface" set during set up.

unitedcases
03-29-2014, 08:23 AM
Going to jump in on this one...my lumber yard like to give me 7/8 boards when I want 3/4 boards. I don't know why. I always have to ask them to rerun them down to 3/4. Anyway the sides and tails of my sled are now at 7/8. That way when they try and give me 7/8 I can make it work. As a precautionary measure I always jog to touch. http://img.tapatalk.com/d/14/03/29/meja5upy.jpg

I was taught years ago the art of using a sled by Al, LG, and Mtyler so I consider myself professionally trained. I went to the back of the sled and drew an index of where to put mounting holes for the various projects I do. Works very well for me. My designs are made on designer using my sled dimensions then I put the artwork or pattern on the sled where I want it. As Dan would say it isn't rocket science. You just have to figure out what works best for you. For me this is seamless when I want to carve something. Very easy to be repetitive. I can post more pics if need be.

kcc2012
03-29-2014, 11:35 AM
I really appreciate this thread about sleds. Not being a woodworker I get intimidated by these types of things. I use a sled when I am scanning an abject and have only used a sled for carving once before which worked great but still no confidence in actually building one that isn't just pieced together.

Ambrose

jakab
03-29-2014, 12:35 PM
As a precautionary measure I always jog to touch.

I have a couple of questions if you don't mind.

1) When you jog to touch, where do you touch? Does it matter, as long as you are on the actual board?
2) When measuring the board (actually the sled, right?) does the CW give you trouble because the ends don't extend the full width?
3) OK, I lied, I had 3 questions :mad:. When the board is measured, is the sled measured, or just the actual board on the sled?

Thanks a lot.

... Peter

unitedcases
03-29-2014, 12:36 PM
My design in designer is the same as the sled. The machine measures the sled and that is the same as what is in the design. Same measurement every time.

jakab
03-29-2014, 01:44 PM
My design in designer is the same as the sled. The machine measures the sled and that is the same as what is in the design. Same measurement every time.

OK, I got that part, but what about when you choose Jog to touch, where do you make the bit touch? On the sled, on the board. If on the board, where, anywhere, or a corner, or does it matter?

Thanks.

...Peter

FWMiller
03-29-2014, 01:46 PM
Where it touches sets the top surface of the carve so it does matter. Touch it on the workpiece, not the sled.

unitedcases
03-29-2014, 01:55 PM
The actual board itself.

jakab
03-29-2014, 02:14 PM
Thanks to both of you.

...Peter

Chip
03-31-2014, 08:24 PM
Unitedcases, I for one would appreciate a couple of more pics of your sled, particularly the bottom :shock:.
As for the ends of the sled, is the sled being measured to the corners of the end pieces or to the corners of the rail?
If measuring to the corners of the rails, what is the purpose of the pieces of wood on each end? :confused:
Pics and reply is greatly appreciated.

unitedcases
03-31-2014, 08:49 PM
Unitedcases, I for one would appreciate a couple of more pics of your sled, particularly the bottom :shock:.
As for the ends of the sled, is the sled being measured to the corners of the end pieces or to the corners of the rail?
If measuring to the corners of the rails, what is the purpose of the pieces of wood on each end? :confused:
Pics and reply is greatly appreciated.

Absolutely. The entire sled is measured. The sled is 39.5 long and 12 inches wide. So my design in designer is those exact measurements. The ends are about 3 inches long but in designer I have 4 inch squares at both ends. The rails are 3/8 inch and in designer I have those drawn out as well. So when I upload a project I just make me design 3/8 from the top and then center it. I have many sleds but this one is for all my 11.25 inch wide boards. I use it to make 11 inch tall pieces. That way I have some wiggle room top and bottom. Everyone does it different. I found that the best way to be quick and somewhat repetitive was to learn the sleds. I think I have 8 or 9. Some don't get used near as often. And I don't think that includes my scanning sled. The bottom is crude but for me, very effective. Rather than have a bunch of holes going thru and wearing the sled itself out I always add a inch on each side of the piece I am carving and fasten it from the backside. Using the grid. All I did was cover it with masking tape and then made a big grid. I drill when I need new holes. Let me know if this helps.

http://img.tapatalk.com/d/14/04/01/bu5epenu.jpghttp://img.tapatalk.com/d/14/04/01/ra9urany.jpg

I used stain grade shelf panels and 3/8 square dowels from lowes. The pine is thick enough to handle the holes and screws but light enough to not add a lot of weight. I used very small nails to fasten the rails on with.

DocWheeler
03-31-2014, 09:26 PM
As for the ends of the sled, is the sled being measured to the corners of the end pieces or to the corners of the rail?
If measuring to the corners of the rails, what is the purpose of the pieces of wood on each end? :confused:
Pics and reply is greatly appreciated.
The end pieces are necessary for the sensor to measure in the X direction.
They need to be at least 1-1/4" to 1-1/2" wide (X direction) to work correctly.

ronboley
04-01-2014, 12:34 PM
Just a thought on sleds...I've found that the machine is a lot more cooperative in measuring and running projects if you use an accurately built sled to hold the work pieces rather than just loading a board. It seems that no matter how flat, square and true you try to mill your board, the machine has issues with measuring the board and/or carving the whole project. The sleds can be built very straight, square and ridged with 1/4" ply bottoms, 1-1/2" wide x 1-1/2" thick (or thicker) rails and 3-1/2" wide end pieces. The board is centered so the "center on board" option can be used.

I make the rails out of the best hard wood scraps I have around and mill them as flat, square and true as possible . I have built four general purpose sleds to fit a variety of "stock" widths and lengths and a couple of special use (long) sleds for specific projects. I've built these sleds over a period of time as I worked on projects so now I have a variety. The attached picture is my sled for a 4" x 24" board (or smaller). I'm currently running 3-1/2" x 24" boards for leg pieces (32 of 'em) on a table project. I shim the board to be centered on the sled. The sleds can be built up to match the boar thickness or filler pieces can be placed below the board to make the board top surface and the sled top surface the same. The current sled is carving boards 1-3/4" thick so I added 1/4" to the top of my 1-1/2" deep sled. I run my sled assembly thru my table saw to make sure the assembled sides are parallel and smooth.

Long boards are especially difficult. I tried to carve 6 foot boards directly with mixed success. It seems no matter how well you place auxillary rollers on the infeed and outfeed, the length causes the board to raise or move and the natural bow of the lumber (always is some) creates real problems with the ability of the machine to measure the board. My fix on my previous table project was to was to build a long sled that helped with the rigidity of the board and took some of the bow out of the problem.

OK more than one thought but that's it.

fwharris
04-01-2014, 12:45 PM
Just a thought on sleds...I've found that the machine is a lot more cooperative in measuring and running projects if you use an accurately built sled to hold the work pieces rather than just loading a board. It seems that no matter how flat, square and true you try to mill your board, the machine has issues with measuring the board and/or carving the whole project. The sleds can be built very straight, square and ridged with 1/4" ply bottoms, 1-1/2" wide x 1-1/2" thick (or thicker) rails and 3-1/2" wide end pieces. The board is centered so the "center on board" option can be used.

I make the rails out of the best hard wood scraps I have around and mill them as flat, square and true as possible . I have built four general purpose sleds to fit a variety of "stock" widths and lengths and a couple of special use (long) sleds for specific projects. I've built these sleds over a period of time as I worked on projects so now I have a variety. The attached picture is my sled for a 4" x 24" board (or smaller). I'm currently running 3-1/2" x 24" boards for leg pieces (32 of 'em) on a table project. I shim the board to be centered on the sled. The sleds can be built up to match the boar thickness or filler pieces can be placed below the board to make the board top surface and the sled top surface the same. The current sled is carving boards 1-3/4" thick so I added 1/4" to the top of my 1-1/2" deep sled. I run my sled assembly thru my table saw to make sure the assembled sides are parallel and smooth.

Long boards are especially difficult. I tried to carve 6 foot boards directly with mixed success. It seems no matter how well you place auxillary rollers on the infeed and outfeed, the length causes the board to raise or move and the natural bow of the lumber (always is some) creates real problems with the ability of the machine to measure the board. My fix on my previous table project was to was to build a long sled that helped with the rigidity of the board and took some of the bow out of the problem.

OK more than one thought but that's it.

Great points on the benefits of using sleds. I've seen the same results.

unitedcases
04-01-2014, 12:55 PM
On ebay I found some adjustable roller assemblies. I mounted them on some scrap 2 X 4s and adjust for every project. Even when they are in the sled sometimes they are still different when it come to bow.

DocWheeler
04-01-2014, 01:22 PM
Just a thought on sleds...I've found that the machine is a lot more cooperative in measuring and running projects if you use an accurately built sled to hold the work pieces rather than just loading a board. It seems that no matter how flat, square and true you try to mill your board, the machine has issues with measuring the board and/or carving the whole project. The sleds can be built very straight, square and ridged with 1/4" ply bottoms, 1-1/2" wide x 1-1/2" thick (or thicker) rails and 3-1/2" wide end pieces. The board is centered so the "center on board" option can be used.

With rails wider than 7/8", you can not simply measure the Y direction with the rails only.
Anything greater or equal one inch requires a continuous area to measure the Y dimension.

Not a criticism of your sled, it obviously works for you.
With narrower rails, you can measure the Y just about anywhere.

ronboley
04-01-2014, 01:29 PM
Yep...just learned that from you yesterday...the learning curve goes on and on and on....Thanks!

DocWheeler
04-01-2014, 01:52 PM
Ron,

I was thinking after I wrote that, perhaps if you used black paint or black
electrical tape to cover the inner 3/4" of your rails, you could still do it.

liquidguitars
04-01-2014, 02:23 PM
What I do and i have over 30 production sleds that i make a asortment of guitars violins amd mandolins, is the following:

Decide the size of your part in my case its 16x8 in designer make a project board that's 10" longer than you part and 2" wider, 26x10 draw a box to the part size 16x8 and center it.

Assign a bit to the box .03 deep in z that you made and upload to the card, place a a 3/4 thick plywood base in the CW that's oversize by .50" in this case the board would be 26.5" x 10.5"

Run the program and use " keep the same" and "place on corner" cut to size no. now you have indexed a placement the corresponds to designer as 1:1 .

pull the sled bottom out of the machine and add 3/4 " dead wood to the lines that designer made, glue and clamp it. Now you have a sled with 4" tails 1" space on each ends to screw the wood down to hold it. When loading the the sled just place the tail under the truck and you will never have a issue indexing the part.

unitedcases
04-01-2014, 05:05 PM
What I do and i have over 30 production sleds that i make a asortment of guitars violins amd mandolins, is the following:

Decide the size of your part in my case its 16x8 in designer make a project board that's 10" longer than you part and 2" wider, 26x10 draw a box to the part size 16x8 and center it.

Assign a bit to the box .03 deep in z that you made and upload to the card, place a a 3/4 thick plywood base in the CW that's oversize by .50" in this case the board would be 26.5" x 10.5"

Run the program and use " keep the same" and "place on corner" cut to size no. now you have indexed a placement the corresponds to designer as 1:1 .

pull the sled bottom out of the machine and add 3/4 " dead wood to the lines that designer made, glue and clamp it. Now you have a sled with 4" tails 1" space on each ends to screw the wood down to hold it. When loading the the sled just place the tail under the truck and you will never have a issue indexing the part.

I wondered when one of you would chime in. You guys should definitely be paying attention now. One of the sled gurus has joined in. LG definitely broke it down for me barney style and learned me.

opensores
05-19-2014, 05:40 PM
Lovely. So can the rails of the sled be .5" thick only? I would like to work with a 13.5" mold width.

With the 13.5" width (between rails on the sled), is it possible to run 12" wide carves? Sounds like a dumb question, but what I am trying to figure out is if it is unwise to be telling the machine its carving, when in fact the bit isn't contacting anything at all for an inch or so...

bergerud
05-19-2014, 05:55 PM
I think I know what you are trying to do and I do not see the need for a sled at all. Why can you not just carve your mold cavity in the middle of a 14.5" wide piece of MDF (or glued stack of pieces) and then cut off the sides in the end? Do you not have a table or band saw?

opensores
05-21-2014, 08:08 PM
This post was meant for another thread...

fwharris
05-21-2014, 08:27 PM
This post was meant for another thread...

You are getting the error because the depth of the carve is 1.25" and the max depth you can carve with the 1/16" carving bit is 0.800" and to top edge of the slice goes way deeper than the base of the pattern. See attached image. This probably has more to do with the error than the carving bit as when I tried to change the pattern bit to the 1/8" long I kept getting the error.