Horizontal Band Saw Machine (copyleft?)

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vesema3
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Horizontal Band Saw Machine (copyleft?)

Postby vesema3 » Wed Jun 12, 2019 1:10 am

Dear community,
I would like to share my idea for a design of horizontal band saw machine. It should be made in such a way so to incorporate readily available standart parts and be able to produce it in home conditions without the need of any expensive machining or tools. For example I haven't still concluded the clamping for the cutted profiles and maybe there are some other things that should be added to the design, and in that respect I was wondering if you can suggest a copyleft license, that will require any following additions or redesigns to be also available for free to the community? Maybe GPL would be the one, but I'm not sure if it can be used for mechanical designs?

P.S.: someone willing to implement it in FreeCAD? :|
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roerich_64
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Re: Horizontal Band Saw Machine (copyleft?)

Postby roerich_64 » Wed Jun 12, 2019 2:36 am

Hi,

i can help to implement it in FreeCAD.
Also a CNC router is here to build anything ;-)

Walter
herbk
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Re: Horizontal Band Saw Machine (copyleft?)

Postby herbk » Wed Jun 12, 2019 5:41 am

Hi vesema3,

for a school project we we use the CERN Open Hardware Licence.
https://www.ohwr.org/project/cernohl/wikis/home
Gruß Herbert
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vesema3
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Re: Horizontal Band Saw Machine (copyleft?)

Postby vesema3 » Wed Jun 12, 2019 9:45 pm

Ok, thanks for the suggestions!
I see, that this open source hardware(design) stuff is like getting into "murky waters" situation, so there is no point to discuss on that any more, but rather get into details about the idea itself.
Before we start, I would point out the following:
1. The design is pretty simple (don't expect much), and actually this is what protects it from being patented or whatever.;
2. The design is not tested at all and I would not take any responsibility if anywhere anything happens.;
3. The design is not fully completed and may require additional ideas or change of an existing ones.;
4. Generally I would like to share my thoughts about the technology, that should be sufficient for the physical creation of the design.;
5. For everything I present here a CERN OHL version 1.2 should apply, where appropriate.

Ok, enough with the bs, here are some pics of what I have done, by hand (+tools), just as a proof of concept for the actual design:
pic_hbs_1.jpg
pic_hbs_1.jpg (29.93 KiB) Viewed 1086 times
pic_hbs_2.jpg
pic_hbs_2.jpg (35.24 KiB) Viewed 1086 times
pic_hbs_3.jpg
pic_hbs_3.jpg (38.78 KiB) Viewed 1086 times
This is as you can imagine the guide for the band saw. There should be a welded flat bar on top (opposite to the nuts). The nuts should be self-locking ofcource, because of the vibrations during the cutting. More info about the standart parts, dimensions and the "technology" used -> maybe tomorrow.

BR
Martin
Last edited by vesema3 on Sat Jun 15, 2019 11:13 am, edited 1 time in total.
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roerich_64
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Re: Horizontal Band Saw Machine (copyleft?)

Postby roerich_64 » Wed Jun 12, 2019 11:04 pm

ok,

i need dimensions of
- bearings
- bolts
- rectangle profile

BR
Walter

Edit: First shoot ;-)
Pic_1.jpg
Pic_1.jpg (222.26 KiB) Viewed 1039 times
Pic_02.jpg
Pic_02.jpg (205.2 KiB) Viewed 1039 times
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vesema3
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Re: Horizontal Band Saw Machine (copyleft?)

Postby vesema3 » Fri Jun 14, 2019 2:08 am

Wow, that was fast! Wish I could also become that fast with FreeCAD.

-bearings- all 3 are 6201-2RS (32x12x10, DxdxB);
-bolts- both are Eyebolts DIN 444 - not sure, which type (B or C), but dim. are: lenght from the center of the hole(d=12H9), to the end of the thread(M12) is 47 mm (they are cutted, the actual lenght is bigger, don't remember exactly); the non-threaded lenght is around 25 mm from the center of the hole(d=12H9); the width between the flats is 14 mm; the sphere head is D=25 mm in diameter.
-rec. profile- 60x40x3(2,8 measured) - L= 60 mm. Its common S235JR electro-welded profile, not very precise.

Additional:
-the washers used as distances are DIN 433 - M12 (precise distances from suitable pipe should be perfect ;) );
-the cylinder pin is DIN 7 - 12m6 x 60;
-there are some DIN 988 - 12x18x0,1 added to the distance stacks, so to create the needed gap for the band saw thickness and also to create minimum clearance with the vertical bearing (the outer raceways should not touch);
-the washers between the profile and the bearings are hardened (its something like DIN6340; dim.: 13x23,5x2,5; dxDxh) and relatively flat compared with the DIN125A under the nuts.
- for the pin I have "axis fixation washers", those which are easy to mount and hard to remove :D.

The hand-made technology I used is:
-the band saw cut-out is made by first drilling a 7 mm through hole on a drilling machine hand stand, then draw tangent lines from the hole, perpendicular to the base side of the profile and with hand metal saw cut along till the holes. The cut-out height is around 17 mm from the center of the 7 mm hole to the bottom side of the profile ;
-as Walter nicely modeled already, there should be one 12 mm base hole for the eyebolts, and instead of a long hole, I made one 13 mm hole for positional compensation and ease of mounting of the second eyebolt (don't drill through the weld! there is no point :) );
-needless to say that the band saw should be centered, and so the supporting parts too;
-because the non-threaded cylindrical surface of the eyebolts has the same outer diameter as the M12 thread (11,85 mm), I used piece of 0,1 mm filler blade to compensate the resulting gap with the bearings ;) .

Need to check my drafts for the other parts and their dimensions. Once again, nice work Walter!

BR
Martin
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roerich_64
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Re: Horizontal Band Saw Machine (copyleft?)

Postby roerich_64 » Fri Jun 14, 2019 2:48 pm

Hi Martin,

The most parts i found in the BOLTS-Macro-Database and i assemble it with A2plus from Klaus:
Pic_04.jpg
Pic_04.jpg (363.38 KiB) Viewed 788 times
Now with M12 parts ;-)

BR
Walter
Last edited by roerich_64 on Sat Jun 15, 2019 7:38 pm, edited 1 time in total.
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vesema3
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Re: Horizontal Band Saw Machine (copyleft?)

Postby vesema3 » Sat Jun 15, 2019 10:30 am

Hi Walter,
actually the initial design I thought of was with pass-shoulder bolt by ISO7379 + securing nut by DIN 985 and washers, but using the DIN 7 pin plus 2x "axis fixation rings" (https://euroboltbg.com/groups/321.jpg) is more cheaper and I think, that the clamping forces from the M12 nuts are sufficient to prevent any post movements of the eyebolts. So to finnish this guiding assembly I've prepared the flat-bar part we spoke of earlier. It should be welded between the radii of the rec. profile - 3 x 10 mm welds per side would be ok. The part should be centered over the face oppopsite to the M12 nuts side of the rec. profile. Not sure if the rec. profile and the flat-bar should be in separate "welding" assembly - its up to you ;).
The gap between the opposing bearings should be 0,65 mm as the design incorporates 13x0,65 band saw. I think it is more common than the 14x0,7 type.
Next will be to show my poor attempts of creating the main beam with FC :( .

P.S.1: I think the washers under the M12 nuts are not DIN125A?
P.S.2: I've noticed that after I saved the enclosed file, FC made another one with .FCStd1 extension. Also I see a message saying "File was not written with this version of the topology" into the Report view - haven't installed anything new except the A2p workbench?
P.S.3: Can't attach the file. When I push submit with file listed for attachment I get: Error window with message "HTTP Error"?
P.S.4: The Hole feature always changes the thread to left, when I reopen the feature - maybe this is a bug?
I will post a picture of the part:
GuideAssem_FlatBar1.jpg
GuideAssem_FlatBar1.jpg (213.17 KiB) Viewed 678 times
BR
Martin
Last edited by vesema3 on Sun Jun 16, 2019 1:17 am, edited 1 time in total.
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roerich_64
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Re: Horizontal Band Saw Machine (copyleft?)

Postby roerich_64 » Sat Jun 15, 2019 11:31 am

You can make drafts with hand. Make a picture and take them here ;-)
Pictures sayes more than thausend words...

FreeCAD-Files you can add with 'drag and drop'
P.S.1: I think the washers under the M12 nuts are not DIN125A?
when you need an other one, you can have it...
the red washers are DIN433 Pos 4, the blue ones DIN6340 Pos 7. Are these right?

Edit [create space for knowns...]:
Push On Fastener [yellow]: https://docs-emea.rs-online.com/webdocs ... 581a20.pdf
spring washers [green]: https://www.schrauben-jaeger.de/tradepr ... DIN137.pdf
washer DIN 125A [gray]: https://www.schrauben-lexikon.de/download/tiso_7089.pdf

be patient for the next drawing...

btw.: your GuideAssem looks good, Martin :-)