Estimate to build these?

[TheEquineFencer]

I'm curious what it will cost to have some gears like this made? I'm just trying to figure out if I want to try to fab them, something like this I've never done, or just bite the bullet and buy them, or see if I can get them made cheaper than buying them. If I can get a few sets made cheap enough, I'd rather farm them out. I'm open to suggestions.

SAE1117 alloy and hardened to Rc 58-62

 

[1953mercury]

They will cost much more to have made than to buy, generally speaking. Mike

 

[kd3pc]

likely several hundred dollars for the 4 of them, assuming you can find someone to set it up or do it.

 

[iajonesy]

Most likely,you will pay a premium for just 1 or 2 sets at a small machine shop. You will be several hundred dollars ahead to just buy them.

Mike

 

[TheEquineFencer]

In the back of my mind I'm thinking they can't be that hard to make. Someone else is making them. I'm wondering if you can buy the steel stock with the splines already cut, then machine the teeth.

 

[shawnspeed]

Ahhh did ya check the boston gear catalog???http://www.bostongear.com/products/open/index.html Even if you bought a gear with no splines, and found a hub with the needed splines and mated the 2 together...

 

[TheEquineFencer]

Ahhh did ya check the boston gear catalog???http://www.bostongear.com/products/open/index.html Even if you bought a gear with no splines, and found a hub with the needed splines and mated the 2 together...

That's sort of what I was thinking. I'm going to look into getting the rear end these gears are going into apart and do some measuring. I may try to buy two gears with the right diameter from a place like above and just machine the outer part off to make the center hub from the OEM gears and weld it to the "new" outer gear.

I'm just kicking ideas around until I get the rear end apart.

 

[SilverSS1969]

In the back of my mind I'm thinking they can't be that hard to make. Someone else is making them. I'm wondering if you can buy the steel stock with the splines already cut, then machine the teeth.

It's not that is hard to make. But the cost adds up quick when you figure in reverse engineering the gear to get the correct dimension, set up time in the lathe, mill and EDM wire or cost of broch to make the ID spline.

Some one else is making them but they ready have the process down. The thousands they have made recoup all the cost. If you make that many parts it would only be a few cents for these services per part. If you only make one or two, these cost don't spread out enough to justify making them.

 

[beltfeed]

Where I work we run off custom straight tooth gears like that are on wire edm once and a while. But first we have to probe a tooth to get the tooth geometry then make a CAD file of the gear. Heat treat the blank if required then wire EDM the ID (spline) and OD. You are looking at probably 8 hrs for inspection and CAD file creation for all 4. And probably 24 to 32 hours wire time for all 4. That is if they are a couple inches in diameter, can't really guess the size from the image. Total cost 4K-5K, not really a good deal for a non industrial customer.

 

[zkling]

Main question...do you have a dividing head? Cutting the actual gear profile wouldn't be the difficult part for me. The splines would be as I no longer have my shaper and no slotter.

How much is a new set from the factory or the source you have?

 

[Divcod]

Take them to a power transmission house, Kaman in our area, and they should have a source for blanks that can be modified to meet your needs. Haven't done this myself in a longtime but used to do it all the time. Hope this helps.

 

[TheEquineFencer]

The set of Gears on the left are the OEM gears. The set on the right are the "overdrive gears." I'm figuring the company that sells them must begetting them either made or are using "off the shelf" gears, or have found a source for getting them done on the "cheap."

It's $200 + shipping for the two on the right. I was wondering if someone with a CNC mill or something like that could "pop them out".

 

[Kevin54]

If you know the gear angle, you can get a cutter to cut the gears. I have one to cut for 383 240Z, but don't know if I can do it, as I can't find a dividing head for a reasonable price. I've been looking for a gear, but running into roadblocks like he did. I may try to just CNC it in the mill, by trying it in a piece of aluminum first.

 

[beltfeed]

The set of Gears on the left are the OEM gears. The set on the right are the "overdrive gears." I'm figuring the company that sells them must begetting them either made or are using "off the shelf" gears, or have found a source for getting them done on the "cheap."

It's $200 + shipping for the two on the right. I was wondering if someone with a CNC mill or something like that could "pop them out".

For $200 you should already have the check in the mail.

 

[Zrexxer]

For $200 you should already have the check in the mail.

Some people just don't know when they're already staring at a bargain.

 

[zkling]

The set of Gears on the left are the OEM gears. The set on the right are the "overdrive gears." I'm figuring the company that sells them must begetting them either made or are using "off the shelf" gears, or have found a source for getting them done on the "cheap."

It's $200 + shipping for the two on the right. I was wondering if someone with a CNC mill or something like that could "pop them out".

The best way for someone to "pop" them out, is on a wire EDM or a laser. Both of which are difficult to find people doing on the side. The downside to that is, as beltfed mentioned, it requires an accurate CAD input file. Which takes time and if you are being billed by the hour, adds up fast.

 

[ranger302]

For $200 you should already have the check in the mail.

I agree with this statement. Unless you are set up for making gears, and have a heat treat house that you trust. Just buy them, you will come out ahead. I am set up to make gears and these would touch $2000 real fast for one set.

 

[TheEquineFencer]

That's my point. If they can sell them for this price, they must be getting them from somewhere "off the shelf" is what I'm thinking. It's just a matter I think of figuring out where they are coming from or knowing how to make them "on the cheap."

 

[ranger302]

Making them "on the cheap" means ordering hundreds if not thousands at a time.

 

[TheModelAGuy]

Try Boston Gear.
http://www.bostongear.com

 

[gorilla]

That's my point. If they can sell them for this price, they must be getting them from somewhere "off the shelf" is what I'm thinking. It's just a matter I think of figuring out where they are coming from or knowing how to make them "on the cheap."

$200.00 is cheap for those gears. It requires a huge investment in equipment and tooling to produce them at that price and a market to amortize the investment over.The only way you will make them cheaper is if you get the use of someones expensive equipment and time for free.

 

[MoonRise]

'custom' made or one-offs are going to be $$$$. Easily in the 4+ bills region.

Next, 1117 steel is never going to get you Rc 60 +/- 2. It's a resulphurized low carbon steel. You'll have to carburize them to get a high carbon case that can get you a hard surface layer and you'll still have a pretty soft core (around Rc 20).

So, to get them 'custom' made, you'd have to get the complete gear tooth specs (and not all gear tooth forms are completely 'standard', sometimes there is a tooth form 'adjustment' off of the standard) and make the teeth. Then after machining the gear teeth and the spline teeth (and there again, spline teeth are not always 100% 'standard', sometimes the size/shape are adjusted slightly for various reasons), you'd also have to heat treat the gears (which for 1117 gears would probably have to include some case hardening as well). Then you'd probably then have to regrind the gear teeth to 'finesse' the size/shape back into spec after the heat treatment distortion.

And depending on the speed/power requirements of the gears, the needed precision for the gear tooth form (size/shape) can easily be in the 'tenths' range. That's ten thousandth of an inch or better (0.0001). (AGMA Class 10 or better)

$200 for the set? Just buy them.

 

[macgyver37]

I charge $75/hour, (I know many shops in my area are higher than I am by alot) so that allows for less than 3 hours to spend on these not counting material or heat treat. The Only way that you are going to get these cheaper than $200 per set is if you plan to do the work yourself or you want to buy a large quantity of them. I guess another way is to find a hobbiest that will do it for the challenge and fun of it for free.

Are you looking into selling them to others? Or do you just want to have another set for yourself. If you are serious about making and selling them yourself, go buy a used gear hob and broaching machine.

The dirt cheapest way to make them would be a shaper with a dividing head so you can use cheap tooling and wouldn't have to buy a gear milling cutter or broach.

If you want to have a stroke, price some broaches for doing splines.

Another idea, just call the vendor and ask for their supplier...... HA

 

[Zrexxer]

Y'all are wasting your breath. The same thing has been said over and over in this thread, but the OP keeps coming back with "yeah, yeah, I know all that but where can I get 'em CHEAP?" Some people will just never catch on.

 

[shocwav3]

If the OP can draw them up in cad, they could be done on a water jet for a minimal investment...Small splines on the lower right may be an issue.

 

[Kevin54]

The best way for someone to "pop" them out, is on a wire EDM or a laser. Both of which are difficult to find people doing on the side. The downside to that is, as beltfed mentioned, it requires an accurate CAD input file. Which takes time and if you are being billed by the hour, adds up fast.

Wire EDM is done all the time around here. As far as an accurate drawing, gears come with a couple standard pitches, so to make a drawing, all you need is one tooth, which is standard, rotate the one tooth around the center point by how many number of teeth the gearing is requiring, and the outside diameter. The bad part about wire EDM is that is cost around $100/inch. Only as a last resort did we resort to wire EDM when making dies, but it does a beautiful job.

The most cost efficient way would find someone that still hobs gears, but most of that has been sent across the water, and not a lot of gear hobbing places around. So for one or two gears, the most cost efficient if you can't find someone with an indexing head and the proper pitch gear cutter, would be to CNC the gear out. But at that, you're looking at an 8 hour or so process/gear depending on the equipment. The smaller diameter of the cutter, the slower the machine has to run.

 

[Kevin54]

If the OP can draw them up in cad, they could be done on a water jet for a minimal investment...Small splines on the lower right may be an issue.

I must have been typing while you posted your reply and didn't see it. I completely forgot about water jet. The drawing would have to be saved as a .dxf extension, and most places can use the .dfx to generate their toolpath.

383 240Z.....you hear that? I'll make a couple phone calls as we have 2 places about 20 miles from me. I can make up a drawing in no time.

 

[KPSquared]

I started reading this thread with interest until I got to the "$200" part. Time to get off the wallet. If you land these in the same spec, one off, for less than that AND have them in hand before 2020, I'll be astounded. This is all crazy to save a few bucks.

 

[TheEquineFencer]

I charge $75/hour, (I know many shops in my area are higher than I am by alot) so that allows for less than 3 hours to spend on these not counting material or heat treat. The Only way that you are going to get these cheaper than $200 per set is if you plan to do the work yourself or you want to buy a large quantity of them. I guess another way is to find a hobbiest that will do it for the challenge and fun of it for free.

Are you looking into selling them to others? Or do you just want to have another set for yourself. If you are serious about making and selling them yourself, go buy a used gear hob and broaching machine.

The dirt cheapest way to make them would be a shaper with a dividing head so you can use cheap tooling and wouldn't have to buy a gear milling cutter or broach.

If you want to have a stroke, price some broaches for doing splines.

Another idea, just call the vendor and ask for their supplier...... HA

I like your ideas. What I'm doing is fishing for ideas. With this smart of a bunch of guys, someone's going to help me solve the "mystery" of how to make these things cheaper than I can buy them. If so, yes, I may try to resell them. Yes, I don't like being told it can't be done.

I was told once I couldn't make a '69 Buick LeSabre out run his '70 Chevelle, but it happened.

 

[KPSquared]

You'll never make them cheaper than you can buy them. Your best bet is to buy them cheaper than you can buy them.

Take a different approach... Start surfing forums and Facebook groups... With enough effort, you'll find someone involved in the manufacture of these gears. Next step, become friends and get deal. You have a way better chance of that than trying to save money with one off custom design and machining.

If being told it can't be done motivates you, then consider yourself motivated! Keep us posted!

 

[TheEquineFencer]

I'm thinking about buying and Scanning them or something like that and getting it converted into a file that points and such could be plotted from. I was hoping something economically could be done to make them. I might be able to get a friend of mine to get them heat treated where he works at a jet engine plant.

 

[ranger302]

Making them "on the cheap" means ordering hundreds if not thousands at a time.

You have been told how to make them "on the cheap". You will not be able to purchase a few few for cheap.

 

[beltfeed]

I'm thinking about buying and Scanning them or something like that and getting it converted into a file that points and such could be plotted from. I was hoping something economically could be done to make them. I might be able to get a friend of mine to get them heat treated where he works at a jet engine plant.

Having a pal do your heat treating is not going to be a big savings. We have are own heat treat dept where I work. Most heat treating shops run dedicated days for each material type. When you are doing large batches in a vacuum furnace the cost is low. You are probably looking at 10 bucks a gear. As far as some suggesting water jetting I would not go there. We have two flow water jets. They have their place in the machining world but not for cutting a gear tooth that meshes with another gear. Heck our laser will cut better then the flows and I wouldn't like that for a tooth finish and fit. Pry open your wallet get $200 out and move on. You are beating a dead horse on this cost savings idea.

 

[Willie Makeit]

... you can always spot the guys that have never stepped foot inside a machine shop

 

[TheEquineFencer]

... you can always spot the guys that have never stepped foot inside a machine shop

LOL, Yeah, and you can tell the guys that think they know everything too....I have a 9x42 BP and LeBlond lathe among a few other nice "non-Machine shop" tools...I hate trolls too...

 

[Kevin54]

I'm thinking about buying and Scanning them or something like that and getting it converted into a file that points and such could be plotted from. I was hoping something economically could be done to make them. I might be able to get a friend of mine to get them heat treated where he works at a jet engine plant.

Equine....If I remember correctly, you have machines as in a mill and a lathe. With that, do you have a Machinery's Handbook? If you do, look up gearing, and the first couple of pages will explain what you have as far as a spur gear. Also a few pages in you will have a chart that tells you your diametrical pitch for the number of teeth to gear diameter ratio. From that, a drawing can be generated. If you need a drawing, let me know, and I'll whip up one for you free of cost. I just need to know your diameter, # of teeth, and the pitch if you know it. The drawing will be a piece of cake.

 

[TheEquineFencer]

Equine....If I remember correctly, you have machines as in a mill and a lathe. With that, do you have a Machinery's Handbook? If you do, look up gearing, and the first couple of pages will explain what you have as far as a spur gear. Also a few pages in you will have a chart that tells you your diametrical pitch for the number of teeth to gear diameter ratio. From that, a drawing can be generated. If you need a drawing, let me know, and I'll whip up one for you free of cost. I just need to know your diameter, # of teeth, and the pitch if you know it. The drawing will be a piece of cake.

I'll get back with hopefully in a day or so on this. I'm still trying to get the DRO working and some tooling... in the middle of some fence jobs here at the house for the G/F. I may try to get the rear end these are going in apart tonight. I'm hoping I can get the measurements from the OEM gears, the new gears it really doesn't matter about the outer tooth profile, just the inner profile for the splined shaft. I did pick up a rotary table for "rough" cutting, it has some run out in it, but it'll probably be ok for use cutting circles or something if I cannot adjust the backlash out of it. It's 12 inch.

 

[gorilla]

It would serve you well to get a copy of Machine Shop Practice by Karl Moltrecht and read up on gear cutting. It might help you understand why some of us who have made gears are somewhat spectral about what you want to do.

 

[TheEquineFencer]

It would serve you well to get a copy of Machine Shop Practice by Karl Moltrecht and read up on gear cutting. It might help you understand why some of us who have made gears are somewhat spectral about what you want to do.

I think I had a copy of that or similar and a few others. When the shop burned down, I lost everything. I'm just starting to get things going again to a degree. LOL, and to top that off, today I finally got out to drive some post here on the farm, it looks like the hydraulic cylinder on the new driver has seized. After this disaster I think I'm going to change my SN.

 

[Kevin54]

I'll get back with hopefully in a day or so on this. I'm still trying to get the DRO working and some tooling... in the middle of some fence jobs here at the house for the G/F. I may try to get the rear end these are going in apart tonight. I'm hoping I can get the measurements from the OEM gears, the new gears it really doesn't matter about the outer tooth profile, just the inner profile for the splined shaft. I did pick up a rotary table for "rough" cutting, it has some run out in it, but it'll probably be ok for use cutting circles or something if I cannot adjust the backlash out of it. It's 12 inch.

A lot of rotary table will have backlash, unless it is an ultra high dollar rotary table that is made for a Haas, or something similar. What you have to do when setting it up, is to make sure you always go in one direction. If you go past your mark, then go back a ways, then go in the one direction to make sure the backlash is out. I always use clockwise turning on the handle so I remember. If I go past my mark, turn it counter-clockwise a half a turn or so, then come back up to your mark. It's a pain, and slow, but it works.

Didn't you have CNC equipment before? If not, then the rotary table is still doable. Once you have your blank centered, start by removing the majority of the material out by just using your "Y" axis and going to your depth times the amount of spaces you have. Tooth number. Then set up the left or right angle of the tooth and cut all of that cut, next the opposite side angle, and cut all of those. So on and so forth, always turning clockwise, and only offsetting your cutter comp and tooth comp. DO NOT try doing a space between each tooth total all at once. If this doesn't make sense, I can give you a quick sketch showing what I mean.