[san83]

Hello -

I have a few questions for you folks.

I bough a new G0704. I ran into issues with less than an hour of run time. I saw heavy smoke coming out of the headstock. I contacted Grizzly and they said it could be the motor winding. They sent me a new motor. I was about to install the new motor, and get ready for the CNC conversion. I dismantled the headstock and I found melted gears, see attached pictures. I have emailed the tech support of Grizzly, and from my past experience with them - they should get back in 3 days and send me the gears.

I don`t want to deal with these plastic gears anymore. I want to do the belt drive conversion, a bit earlier than I wanted to. I don`t have the ability to machine right now as the machine is down, and I don`t want to put back the machine together and then tear it down again for the belt drive conversion. I also don`t have a lathe.

Here are the questions -

1] What is a good kit out there for a belt drive conversion? Should I use the stock motor or upgrade to a different motor. I see 1100 W motors are almost 600$. Is it worth the upgrade.
NOTE : I don`t want the quill function or the fine feed.
2] What kind of lubrication do I need for dove tails ways? Can someone link me to online place I can buy from.
3] What kind of lubrication do I need for rest of the machine?

Best,
San

[Fastest1]

Bench Top Precision makes a great kit that requires no machining. A simple bolt on. Very well done too.

[san83]

BTP has a long lead times from what I have seen. Is anyone aware of someone who stocks the conversion kits?

[Fastest1]

He might have a long lead time on a custom kit. Usually he is pretty fast. Might even have it in stock.

[san83]

Does anyone have knowledge of the belt drive kit from Home Machine Shop HMS G0704 / WMD20 Belt Drive (Stock Motor)

[CL_MotoTech]

I have the HMS kit (but with a brushless motor) and like it a lot. Others seems to think that it should be more feature heavy, but it's been working well for me.

[san83]

@CL_MotoTech - Feature heavy as in different pulley settings? And what else? I plan on using the motor the G0704 came with. Did you upgrade your bearings?

Are the belts easily available?

[CL_MotoTech]

Yeah, different pulley settings seems to be desired by many. If you power tap it's probably necessary. I converted to AC bearings, the verdict is still out, but so far it's been okay.

I'm not sure what belt the stock motor conversion kit uses, but the belt for the brushless kit is easily found. I would be willing to bet it uses a similar belt.

https://www.amazon.com/Gates-5M365-P...rds=5m365+belt

[109jb]

My experience was that the stock motor needed the low gear to drill anything larger than about 3/8". I would think that the single speed pulley would be the same. I never looked into my stock motor or speed control too much though, so maybe mine was weak.

[CL_MotoTech]

I used my machine for a year without breaking a single set of gear. Maybe you're just asking too much from them and the motor?

[Fastest1]

I used my machine for a year without breaking a single set of gear. Maybe you're just asking too much from them and the motor?

Nope it is a plastic gear. Poor design.

[coherent]

Nope it is a plastic gear. Poor design.

With this type of design the plastic gears used in the 2 locations afford something to "give" in the event you accidentally run a end mill into a work piece at excessive cut depth. I also quickly did a belt drive upgrade on mine after my first plastic gear got chewed up/melted. At least with the belt drive the belt and pulley system offer more of a safety feature than chewing up metal gears. I'd highly recommend replacing the existing spindle bearings with some better AC bearings. It will likely run at the very least a little faster RPM with a belt drive depending on your pulley selection and my stock bearings ran extremely hot even at fairly moderate speeds with the stock setup. Grizzly even sent me replacement bearings for the issue. Even with the new bearings and the bearing preload set correctly I had issues... belt drive and new bearings fixed all of those issues.

[Fastest1]

The only thing I want to "give" is the workpiece. Either cut the project or break the end mill but don't junk the machine over it.


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[109jb]

The only thing I want to "give" is the workpiece. Either cut the project or break the end mill but don't junk the machine over it.


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I would have to disagree a bit with this. While I see your point, for a small machine such as this you aren't going to break something like a face mill, or 3/4" EM. If you try to take too much cut with a cutter that won't break and stall the machine, the magic smoke can leak right out of the DC motor if the machine totally stalls. I would much rather have a low cost plastic gear strip than burn up the motor.

The gear shown here is not the one that usually breaks. It is usually the single upper gear. After hearing about that gear stripping, I ordered 2 spares, and I still have 2 spares. I have not had a problem with the stacked gear stripping either, but it is undoubtedly plastic since the head is not an oil bath type setup.

[Fastest1]

I was never impressed with the gears or the motor. Both have been replaced.


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[bgriggs]

I have all the gears and original parts I took off my G0704 if you are looking for parts.

Bill

[sharat]

The Belt drive kit from HMS is on the way. I`m also upgrading the spindle with new bearings from VBX. The only issue is the 1mmx25mmIDX35mmOD shim spacers are out of stock at McMasterCarr and expected to ship in two weeks. That`s a long wait. Does anyone have extra I can buy from. I know they come in a pack of 10 and you only need 4.

[CL_MotoTech]

Send me a Pm, i'm pretty sure I have enough shims to get your setup. I'll have to check when I get to the shop though.

[bgriggs]

If any one is looking for replacement parts for their G0704, let me know. I did the full Phase 3 conversion and added a 3 Phase motor. The original motor might have an hour worth of run time at most. Everything is wrapped in plastic and has been lubricated. Attachment 334882