# Are these any good?



## HMF (Jan 18, 2020)

What do you guys think of these plastic 3D printed metric sets? Will they  stand up?




SOUTH BEND HEAVY 10 METAL LATHE METRIC TRANSPOSING CHANGE GEAR SET 3D Printed

Condition: New

ITEM PRICE:US $64.00
TIME ENDS:Feb-08,01:06 PM
SELLER:       fdmprinters(364)Feedback score is 364 for fdmprinters100% positive feedback


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## SLK001 (Jan 18, 2020)

A lot of people have used them and say good things about them.  I imagine for anything less than 1mm pitch they would perform okay.  Larger pitches might pose some problems.

Also, they aren't a true transposing gear set, but are instead an "approximating" gear set.  My question, is if they can print an approximating set, why can't they print a true transposing set (ie, 127/100)?

Is that a Heavy 10 there?


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## Downunder Bob (Jan 18, 2020)

SLK001 said:


> A lot of people have used them and say good things about them.  I imagine for anything less than 1mm pitch they would perform okay.  Larger pitches might pose some problems.
> 
> Also, they aren't a true transposing gear set, but are instead an "approximating" gear set.  My question, is if they can print an approximating set, why can't they print a true transposing set (ie, 127/100)?
> 
> Is that a Heavy 10 there?



Should be ok for occasional light use. A lot of smaller lathes don't have enough room to swing a 127 gear. Most lathes under 10" don't have the room and not even all 10" lathes can do it.

Note some larger lathes also use 127 x 120, depends on lead screw and other gears in the chain. my 12" does.


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## coherent (Jan 18, 2020)

I think if you have a crash, it's a good idea to have plastic gear in the chain somewhere. I have some 3d filament that you anneal in the oven after you print it. It's definitely stronger than your typical plastic and has a much higher temp rating.


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## SLK001 (Jan 18, 2020)

Downunder Bob said:


> Should be ok for occasional light use. A lot of smaller lathes don't have enough room to swing a 127 gear. Most lathes under 10" don't have the room and not even all 10" lathes can do it.
> 
> Note some larger lathes also use 127 x 120, depends on lead screw and other gears in the chain. my 12" does.



My H10 uses the 127/100 combo and it fits just fine.  In fact, all the SB lathes could fit the transposing gears in the gear train.  The back end of the photo looks like a Heavy 10, but now I realize that photo was from the ebay listing, not H-M Founder's lathe.

I do know that some larger lathes need the 127/120 combo.  My lead screw is 8 TPI.  The 127/120 combo is for the 6 TPI machines.


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## MrWhoopee (Jan 18, 2020)

I made my own 80/63 set using gears from Boston Gear. If you use the 80 that's already on the lathe, you only need a 63, 36 and 32 to get all the common metric pitches. The hardest part was producing the 3/16 keyway without a broach or press. Yes, it's not an exact transposition, but it is so close that for practical purposes the difference is negligible.


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## middle.road (Jan 18, 2020)

None of the listing state what material they're using. Might want to find out about that.
Here's a possible budget friendly idea.
Are there any 'Maker's Spaces' near you in NYC?
I believe that the model for that gear is available for free download.
Haven't found it yet but maybe one of the folks more familiar with the 3D printing sites can chime in.


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## benmychree (Jan 18, 2020)

SLK001 said:


> My H10 uses the 127/100 combo and it fits just fine.  In fact, all the SB lathes could fit the transposing gears in the gear train.  The back end of the photo looks like a Heavy 10, but now I realize that photo was from the ebay listing, not H-M Founder's lathe.
> 
> I do know that some larger lathes need the 127/120 combo.  My lead screw is 8 TPI.  The 127/120 combo is for the 6 TPI machines.


127/120 also works with 4TPI screws.


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## Eddyde (Jan 19, 2020)

I can print the gears if you send me the files.


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## SLK001 (Jan 19, 2020)

Eddyde said:


> I can print the gears if you send me the files.



Now this seems like the best solution of all!


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## Matthias (Feb 14, 2020)

SLK001 said:


> Now this seems like the best solution of all!


Hi there,

Is there someone who allready have these files?


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## projectnut (Feb 14, 2020)

coherent said:


> I think if you have a crash, it's a good idea to have plastic gear in the chain somewhere. I have some 3d filament that you anneal in the oven after you print it. It's definitely stronger than your typical plastic and has a much higher temp rating.



Composite gears have been around for quite a while.  Sheldon used them as far back as the 1950's.  My 13" (MW-56-P) machine has a phenolic gear in the train.  As mentioned it's there as a sacrificial element in the event of a crash.  It also helps quiet the gear train.  The only downside I'm aware of is that being soft occasionally a piece of swarf gets caught in the teeth.  When that happens there's a rhythmic thump, thump, thump, every time that tooth engages with the corresponding gear.  Thankfully I can open the cover and remove the swarf with a dental pick.

I would guess with continual use this gear would be the first to wear out.  However the original gear on my machine was replaced as part of a rebuild in 2014.  Having lasted 54 years, I doubt I'll be having any trouble in the near future.


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