# 3D printed bevel gear



## Gordon (Sep 14, 2020)

Is there a program to generate a 3D printed bevel gear. I have an old Sears band saw and it has a small bevel gear about 2" dia. I have found a drawing of the gear and I have a 3D printer but my CAD expertise is not up to drawing the gear. I thought perhaps there is a stand alone program to do this.

Gordon


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## RM-MN (Sep 14, 2020)

I don't have much CAD experience but I do a little mucking about with FreeCAD.  There is an addon that generates gears, also free.  There is a section just for bevel gears so if you want to download FreeCAD, there is an add on manager in the tools tab that lets you add the gear generator.

What CAD have you used?  There may be a bevel gear generator built in.


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## johnmcc69 (Sep 14, 2020)

Hi Gordon, there are a few sites out there where you can input your gear criteria & it will create the CAD model for you & allow you to download it in various 3D formats. I've only used them as "representations" in my CAD modeling, so can't vouch for their accuracy...

 But, if you send me the specs, I'll model it up for you in 3D CAD & give you a usable (modifiable) printer file.
 -I have more faith in creating some models from scratch, & "Machinery's Handbook" has never let me down..

 John


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## jkimberln (Sep 14, 2020)

I think you could find what you want at Thingiverse.  You could look for a program written in OpenScad as it would be variable in a number of parameters.  That way you could get the size, number of teeth, angle, etc. that you need.  Thingiverse has a large number of gear files.

JerryK


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## dsage (Sep 15, 2020)

Gordon:
Have a look on McMaster Carr or one of many Gear suppliers. If the gear you are looking for exists you can usually download it as a CAD file to suit your program and it will be accurate. Once you have the CAD file you can export it easily enough with your CAD program to STL format and then you should be able to simply (?) print it on your 3D printer (with all that is required in that effort i.e slicing etc. ect). 
There is a possibility you'll find the gear tooth pattern and size you require but it has a boss or maybe the wrong hole size or something. But editing it with the CAD program to suit shouldn't be too difficult.

The other issue to consider is - Will the gear will be durable enough made from plastic.


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## Henry K (Sep 15, 2020)

I had a Sears table saw years ago. My wife's uncle used it once, tilted the table and broke teeth off the gear. In his defense, it required a lot of stress on the gear to tilt the table even though it was working properly - a design problem. Since 3D printed stuff is frequently 70 % air I doubt it would work unless you set the printer to be nearly 100 % plastic and even that may be a stretch.


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## Gordon (Sep 15, 2020)

I have looked at several distributors of bevel gears with cad drawings. It appears that this gear is kind of an oddball. It is 16 pitch with 28 teeth. The original was plastic so that should be OK. The original lasted for probably 40 years with light home use. A couple of years ago the gear stripped and I could not find a replacement so I kind of cobbled a replacement in brass using large and small diameter and cutting with a gear cutter with the gear set at an angle and indexed on a rotary table. That seems to work but is noisy.  At that time I did not have a 3D printer so the machined version was the only option. I recently had to replace the tires and I had to tear the machine apart so I thought that this would be a good time to make a new gear. Parts from Sears are no longer available.

I have played around with Free Cad in the past and I have found the add on but I have to reeducate myself on how to use Free Cad. I will keep trying.


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## awake (Sep 15, 2020)

As someone who has machined gears out of plastic, and has 3d printed gears in plastic, I can offer one person's first-hand experience: the printed gears do not hold up well, while the gears I've machined out of plastic have held up just fine.

My experience is based on 3d-printing gears out of ABS and PETG, with many variations of perimeter and infill settings and different layer heights. The gears in question have been module 2 gears (so, somewhat larger - not tiny) and experience a fair bit of stress. Infill has not been the problem; rather, the teeth strip too easily. I have attempted to 3d-print these gears out of nylon, hoping they would hold up better, but have not been successful in keeping the nylon print from warping. (One of these days I'll make an enclosure and try again ....) I also have some POM filament (trade name Delrin), but it warps even more than the nylon, so again, waiting on an enclosure.

Obviously there is success to be had in some applications, since many 3d extruders use printed gears. It may be that have succeeded even with gears undergoing a greater stress than in an extruder, and if so, I will be very eager to hear about it - I'd like to know how to achieve success!


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## Gordon (Sep 15, 2020)

awake said:


> As someone who has machined gears out of plastic, and has 3d printed gears in plastic, I can offer one person's first-hand experience: the printed gears do not hold up well, while the gears I've machined out of plastic have held up just fine.
> 
> My experience is based on 3d-printing gears out of ABS and PETG, with many variations of perimeter and infill settings and different layer heights. The gears in question have been module 2 gears (so, somewhat larger - not tiny) and experience a fair bit of stress. Infill has not been the problem; rather, the teeth strip too easily. I have attempted to 3d-print these gears out of nylon, hoping they would hold up better, but have not been successful in keeping the nylon print from warping. (One of these days I'll make an enclosure and try again ....) I also have some POM filament (trade name Delrin), but it warps even more than the nylon, so again, waiting on an enclosure.
> 
> Obviously there is success to be had in some applications, since many 3d extruders use printed gears. It may be that have succeeded even with gears undergoing a greater stress than in an extruder, and if so, I will be very eager to hear about it - I'd like to know how to achieve success!


Sounds like my best bet is to just stick with the brass and make another if it wears out. Obviously this is not a precision piece. If I start replacing too many parts on this saw it is just going to be cheaper to replace it. I am finding that the roller guides are also pretty worn and they also are not available. I saw the same saw on craigslist or facebook a while back for $40 and thought that is just like mine. I should have bought it but that was before the tire came off on mine. Now I have $30 in new tires and I am having trouble keeping the blade on it.


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## popnrattle (Sep 16, 2020)

I drew a bevel ring and pinion(4.11 to 1 ratio) along with the spiders and printed them as part of an auto differential display to show students how it works. I uploaded my 2 procedures using CAD and Inventor(correct or not) to you tube if you care to take the time. The musical accompaniment may not appeal to you so just mute it.


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## n1326e (Sep 16, 2020)

Try 'Gearotics'   "Gearotic Motion Gear design Software"
Tom


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## MrBoo2u (Dec 30, 2020)

johnmcc69 said:


> Hi Gordon, there are a few sites out there where you can input your gear criteria & it will create the CAD model for you & allow you to download it in various 3D formats. I've only used them as "representations" in my CAD modeling, so can't vouch for their accuracy...
> 
> But, if you send me the specs, I'll model it up for you in 3D CAD & give you a usable (modifiable) printer file.
> -I have more faith in creating some models from scratch, & "Machinery's Handbook" has never let me down..
> ...




Is it possible you could draw this up for me I have the same saw and am currently unable to use it because of a broken tooth on the nylon bevel gear I have access to a 3d printer but limited cad experience to draw one up. I can send pics and measurements or post them. Im pretty sure the OP has the same saw its a Craftsman Commercial horizontal bandsaw . The saw was made under a few names Atlas was one of them but the part no longer exists. There was a guy in another forum printing them but he kind of disappeared


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## Gordon (Dec 31, 2020)

MrBoo2u said:


> Is it possible you could draw this up for me I have the same saw and am currently unable to use it because of a broken tooth on the nylon bevel gear I have access to a 3d printer but limited cad experience to draw one up. I can send pics and measurements or post them. Im pretty sure the OP has the same saw its a Craftsman Commercial horizontal bandsaw . The saw was made under a few names Atlas was one of them but the part no longer exists. There was a guy in another forum printing them but he kind of disappeared


I ended up machining one from brass. Kind of a crude operation. Machined the blank and put it on the tilted rotary table and cut the teeth with one of my metric cutters which was the closest fit. Works but is noisy.

Found a site which sells the gear: Sears/Craftsman Band Saw Bevel Gear - Part 341-299 by taylorsizem_re on Shapeways

Drawing: Covel Manufacturing Co. - Publication Reprints - 341-299 Horizontal band saw bevel drive gear | VintageMachinery.org

Look for Clausing part number 341-299 and there are a couple of places showing a drawing for the gear. I started to try to figure out how to generate a drawing and soon decided that the learning curve was too steep since I had already made my brass gear and it was working.


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## MrBoo2u (Jan 1, 2021)

I may have to go the same route as you. But im going to have to find a tilt rotary table as Im lacking that in my home shop but really hoping to find someone to draw this up in a cad 3d model that can be posted up so others can print it themselves. Im working on trying to figure it out myself right now just having to figure out which free cad system is going to be the best for me since I havent touched cad in a few years and mainly used mastercam but drawing gears is new to me .

but thankyou for the links the print wll come in very handy


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## johnmcc69 (Jan 1, 2021)

I would like to see a pic of the actual gear, especially the tooth "form". The drawing Gordon shows states it a "Gleason" style gear, the one being sold in "Shapeways" appears to have a straight cut profile. I just need to know the tooth profile a little better (Circular thickness?)

 John


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## TSutrina (Jan 1, 2021)

freeCAD 18 has a work bench to design gears including bevel gears.     covers all types of gears  but you may want to start with a tutor on  spur gears     the text for bevel gears  FCGear BevelGear - FreeCAD Documentation.     I have designed gears but have not printed them, however.  Pete Tubalcain has built gears and used them on his lathe.  https://www.youtube.com/channel/UCKLIIdKEpjAnn8E76KP7sQg

freeCAD is free and goes on the popular computers.   You can store them as step and stl files to use hour slicer.  I have printed parts I design on my Tornado.    And there are many tutors to get familiar with using the software.  Get control of what you print by being able to make a 3D model.


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## MrBoo2u (Jan 1, 2021)

johnmcc69 said:


> I would like to see a pic of the actual gear, especially the tooth "form". The drawing Gordon shows states it a "Gleason" style gear, the one being sold in "Shapeways" appears to have a straight cut profile. I just need to know the tooth profile a little better (Circular thickness?)
> 
> John




heres a couple pictures of the actual gear


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## Donrecardo (Jan 2, 2021)

Have you tried this , it generates all kinds of gears , bevel spur herringbone rack etc 
just input the parameters you want and it will generate a file for you
runs on the free open scad program








						GitHub - chrisspen/gears: OpenSCAD gear generator.
					

OpenSCAD gear generator. Contribute to chrisspen/gears development by creating an account on GitHub.




					github.com
				




Don


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## Chiptosser (Jan 2, 2021)

Gordon,  If you are having trouble with the blade waking, you have other issues.
Is the blade new?  If it is used and you installed the new tires, the blade could have a bow in it.
If you lay the blade on a flat surface, does it lay flat?
Are the tires running true on the wheels?   If every thing is running true, your wheel alingment may need adjusted on the top tracking wheel mount. The blade rollers , or cam rollers as they are call by some. They are out there you just have to keep looking.


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## Gordon (Jan 2, 2021)

Chiptosser said:


> Gordon,  If you are having trouble with the blade waking, you have other issues.
> Is the blade new?  If it is used and you installed the new tires, the blade could have a bow in it.
> If you lay the blade on a flat surface, does it lay flat?
> Are the tires running true on the wheels?   If every thing is running true, your wheel alingment may need adjusted on the top tracking wheel mount. The blade rollers , or cam rollers as they are call by some. They are out there you just have to keep looking.


Solved that problem back in September. The problem was that the new tires were slightly wider than the groove in the drive wheel. That meant that the tire did not go all of the way down in the groove and made a high ridge which would not let the blade track. I ended up machining a little bit out of the groove so that the tire went all of the way down in the groove and now it tracks.


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## Gordon (Jan 2, 2021)

johnmcc69 said:


> I would like to see a pic of the actual gear, especially the tooth "form". The drawing Gordon shows states it a "Gleason" style gear, the one being sold in "Shapeways" appears to have a straight cut profile. I just need to know the tooth profile a little better (Circular thickness?)
> 
> John


I don't think that anything has to be that precise. I made the brass gear using a very crude setup and it works. I think that anything close would work. Gleason system seems to just refer to the company which makes the gear cutting machine.


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## Gordon (Jan 2, 2021)

MrBoo2u said:


> I may have to go the same route as you. But im going to have to find a tilt rotary table as Im lacking that in my home shop but really hoping to find someone to draw this up in a cad 3d model that can be posted up so others can print it themselves. Im working on trying to figure it out myself right now just having to figure out which free cad system is going to be the best for me since I havent touched cad in a few years and mainly used mastercam but drawing gears is new to me .
> 
> but thankyou for the links the print wll come in very handy


You do not need a tilting rotary table. Just set the rotary table at about 5° off from the mill table. Half of 9°59' on the drawing. I think that even a home made gear cutter would be close enough.

The main reason that I gave up on the 3D print is as someone else pointed out the PLA is not strong enough to hold up under the stress and running in the chips that this gear is subjected to.


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## johnmcc69 (Jan 2, 2021)

Worth a shot?
(Crude dimensioning shown on drawing to verify some measurements...)
 STL file is full scale to the drawings, you'll have to rescale it for shrink depending on the material you use...
John


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## Gordon (Jan 4, 2021)

johnmcc69 said:


> Worth a shot?
> (Crude dimensioning shown on drawing to verify some measurements...)
> STL file is full scale to the drawings, you'll have to rescale it for shrink depending on the material you use...
> John


I am a long way from an expert on 3D printing and I have not used it for a while but I tried loading your stl file and I am not getting any thing on the Z axis. Just a flat outline. I will try again later when I get more time. I am using Ultimaker Cura software. I am sure that it is operator error. Thanks


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## kvom (Jan 4, 2021)

I have a copy of Gearotics that can model the gear and output an STL.  Post all the dimensions, and I'll generate it.


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## Gordon (Jan 4, 2021)

kvom said:


> I have a copy of Gearotics that can model the gear and output an STL.  Post all the dimensions, and I'll generate it.


John has generated an STL and and a PDF but I am having a problem loading it into my software. I am sure that the problem is with me, not the files.


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## Gordon (Jan 4, 2021)

Played around with it a little more. I have the part showing but I still need more work. More later after I take care of some other stuff


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## MrBoo2u (Jan 4, 2021)

Gordon said:


> You do not need a tilting rotary table. Just set the rotary table at about 5° off from the mill table. Half of 9°59' on the drawing. I think that even a home made gear cutter would be close enough.
> 
> The main reason that I gave up on the 3D print is as someone else pointed out the PLA is not strong enough to hold up under the stress and running in the chips that this gear is subjected to.




PLA isnt but it can be printed in petg or abs both are more suitable for gears


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## MrBoo2u (Jan 4, 2021)

Gordon said:


> Played around with it a little more. I have the part showing but I still need more work. More later after I take care of some other stuff



thankyou


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## Gordon (Jan 5, 2021)

MrBoo2u said:


> thankyou


I have only used PLA. I have a Monoprice Mini printer. I am not sure if it will use other filaments. I will have to do some more investigation.


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## MrBoo2u (Jan 5, 2021)

Gordon said:


> I have only used PLA. I have a Monoprice Mini printer. I am not sure if it will use other filaments. I will have to do some more investigation.





it should I know the monoprice mini v2 will print abs petg wood pla pla+ metal composites and several other filaments
I have a longer lk4 that will as well. Most printers will print abs and petg along with PLA


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## TSutrina (Jan 6, 2021)

A free  3D design program that has gear modeling including bevel is freeCAD, windows, mac, and lenox software.  When the software is loaded go to tools and at the bottom add on managers.  I have used the STL model from FreeCAD and built and sliced them with Cura and printed them on my Tovo Tornado filament printer.
Text on gears looooo/freecad.gears
Video on gears:   
As far as casting and PLA printed gear.   Can print a negative model and fill this with cast silicone mold  I would make a two part or more mold so the rubber can be removed.  Draft is not a problem.  Then paint on a thin layer of plaster with fine sand to keep shrinkage down.  After a few coats then coarse sand can be used.  Then use sand to support this coated gear when casting.  Solid plaster crack.  There is a special plaster for casting.  And even then thin coating are used for big castings.  Best bet with HDW plaster is to keep thickness down.  You can find investment casting of bronze information on the web.  Plaster needs to be dried and warm before casting to keep thermal shock which causes cracking.
As far as metal ZAMAC is the choice for decades on Atlas lathes gears.  It an alloy with high strength and low melting temperature.   With the thousands of laths sold to hobbyist it is the best choice and you can cast a new one.  This article on using ZAMAC for repair shows the process for casting.  https://rick.sparber.org/zrp.pdf


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## MrBoo2u (Jan 6, 2021)

Gordon said:


> Played around with it a little more. I have the part showing but I still need more work. More later after I take care of some other stuff




I played with it a bit in both tinkercad and freecad. from what I saw it was drawn in mm with inch dimensions so I blew it up converting it to the proper mm measurements. feel free to rename the file I forgot to clear a file name and this is just what it saved under lol

This one shows up in proper dimensions in cura slicer for printing. shows about 2 1/2 hours print time for my printer


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## Gordon (Jan 6, 2021)

MrBoo2u said:


> I played with it a bit in both tinkercad and freecad. from what I saw it was drawn in mm with inch dimensions so I blew it up converting it to the proper mm measurements. feel free to rename the file I forgot to clear a file name and this is just what it saved under lol
> 
> This one shows up in proper dimensions in cura slicer for printing. shows about 2 1/2 hours print time for my printer


I have loaded it into my printer and it is printing now. NOTE: I am not an expert on either 3D cad or 3D printer. 

The earlier version by John was 35kb and this one is 5256kb. I tried printing the one from John and it just gave me single layer. This one looks t be correct except that it is printing it standing on edge instead of having the hub flat against the table. It may end up OK but it is going to have a lot of overhang. I will know in a couple of hours how it turns out.

I am presently printing using PLA because that is all that I have. If it turns out OK I will buy some ABS and try again.

Thank you for your efforts.

Gordon


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## Gordon (Jan 6, 2021)

Gordon said:


> I have loaded it into my printer and it is printing now. NOTE: I am not an expert on either 3D cad or 3D printer.
> 
> The earlier version by John was 35kb and this one is 5256kb. I tried printing the one from John and it just gave me single layer. This one looks t be correct except that it is printing it standing on edge instead of having the hub flat against the table. It may end up OK but it is going to have a lot of overhang. I will know in a couple of hours how it turns out.
> 
> ...


I just stopped the print because there is not enough support on the piece and it is too unstable to print. There must be some way to rotate it so that the gear is setting either on the hub or the face. Beyond what I know how to do at this point so I will have to try to educate myself. I played around a little bit with FreeCad several months ago but I will have to re educate myself.


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## Gordon (Jan 6, 2021)

OK That was easier than I thought it would be. I just rotated it in CURA and started a new print. Looks OK so far. It is going to be working on this after I quit for supper. Says 8 hours and 26 minutes. It is going to work without supervision.

Than you.

Gordon


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## johnmcc69 (Jan 6, 2021)

Some interesting observations there.
 I created the CAD model drawn in inches so I'm not sure why it had to be resized.
 Could it be when you import the file to your slicing software that it's default import settings are metric & would need to be changed to inch units?

 I can't explain the file size difference, when I created the STL file I just used the default settings. The model did appear "coarse" when I import it back in. I can tweak those settings if need be. 

 If you would like, I can send you a STP file to import into your CAD program so you can play with the export settings & see what works for you.

 John


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## MrBoo2u (Jan 6, 2021)

johnmcc69 said:


> Some interesting observations there.
> I created the CAD model drawn in inches so I'm not sure why it had to be resized.
> Could it be when you import the file to your slicing software that it's default import settings are metric & would need to be changed to inch units?
> 
> ...




the stl I downloaded showed up as metric in both freecad, tinkercad and fusion360 so Im not sure what happened. it took me a bit to figure out what was going on as it looked fine in cad but when I sent it to cura slicer it only would show up as a spec. it was when I blew up the spec in cura I realized the stl file was showing all the measurements in mm but it woud be great to see if you could refine it so we can pin the file here for other users that may need this gear as well. Im currently waiting on some abs materal to come in and then I will try to print it as well


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## MrBoo2u (Jan 6, 2021)

Gordon said:


> OK That was easier than I thought it would be. I just rotated it in CURA and started a new print. Looks OK so far. It is going to be working on this after I quit for supper. Says 8 hours and 26 minutes. It is going to work without supervision.
> 
> Than you.
> 
> Gordon



wow 8hrs the difference in print times with some printers is always interesting to me, Cura says print time for my longer lk4 is 2 and 1/2 hours. going to be interesting to see. I may try printing one tomorrow out of pla just to see while I wait for the abs filament to come in in the next few days or months lol never know with usps mail anymore


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## Gordon (Jan 7, 2021)

I printed it using PLA and it looks good. I have not tried it on the machine but it looks right. It did indeed take 8 1/2 hours. The Monoprice is a very basic and cheap machine and for the few times I use it it is just fine. It is not like I have to stand there and watch it. It was still working when I went out to the shop to check. I finished at some time while I was in the house. I will probably try printing one later with ABS just to have as a replacement part. The saw is presently working with my crude brass gear and the saw is not used a great deal.

Thanks for everyone's efforts on this.

Gordon


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## johnmcc69 (Jan 7, 2021)

Can you post some pics Gordon?

 John


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## Gordon (Jan 7, 2021)

Here is the final result.


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## johnmcc69 (Jan 7, 2021)

Looks good! 

 John


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## Gordon (Jan 7, 2021)

It is too much work to tear the saw down to actually try it but as near as I can tell it should work, or at least work when/if I print it using ABS.

The bore seems to be a little tight but it probably can be pressed on or at worse run a reamer through it.


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## MrBoo2u (Jan 7, 2021)

Looks good ,I will be assembling mine shortly as well so I will let you know how it goes good work guys


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## Gordon (Jan 22, 2021)

MrBoo2u said:


> Looks good ,I will be assembling mine shortly as well so I will let you know how it goes good work guys


So did it work?


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