Stahl dozer gear boxes and drive motors

[rc13]

I looked all over the place for the correct pinions needed for this mod... I bought some pinion gears from a few diff. suppliers. One set wasn't quit long enough and the other set had a tad too big of a diameter. Couldn't get answers from them prior to purchase, so I took the chance and bought them anyway. They were only a few bucks.

So, I talked to someone at SDP/SI (Stock Drive Products / Sterling Instrument). I gave him the exact measurements. The rep directed to me to the parts on their site where I could purchase some pinion stock. It is sometimes nice to get live help over the phone instead of by email.

https://www.flickr.com/photos/146664.../shares/78471Q

So I bought 2. They are what I was looking for. Now I can just cut them to the correct length. Oh, and drill the 2mm bore. I better do that first..

Also, I going to see about getting the original gearbox repaired.

[SmallHaul]

That is great that you found the gears. I wouldn't drill the gear out to 2mm because you want a pressed/interference fit. Make the hole .002 (two thousandths) smaller than the shaft and press the gear on.

It is best to practice on similar material making the interference hole because when you drill the hole it will often be larger than the size of the bit when you measure the shaft. Drilling a hole accurately to the thousandths of an inch is a bit of an art (pun intended).

A good read:

https://www.quora.com/Machining-If-I...resultant-hole

What i have found that works well is to make a pilot hole about .01 (ten thousandths) smaller than your final hole size and then allow the part to cool and then run the final bit size through it.

[rc13]

Originally Posted by SmallHaul

That is great that you found the gears. I wouldn't drill the gear out to 2mm because you want a pressed/interference fit. Make the hole .002 (two thousandths) smaller than the shaft and press the gear on.

It is best to practice on similar material making the interference hole because when you drill the hole it will often be larger than the size of the bit when you measure the shaft. Drilling a hole accurately to the thousandths of an inch is a bit of an art (pun intended).

A good read:

https://www.quora.com/Machining-If-I...resultant-hole

What i have found that works well is to make a pilot hole about .01 (ten thousandths) smaller than your final hole size and then allow the part to cool and then run the final bit size through it.

Good point about drilling the hole .002 smaller for the finished hole. I will do that. The true measurement of the motor post with my caliper is 1.96mm. I definitely don't want that slipping...

I usually drill holes with a little smaller bit than my finish bit, but I will definitely do that on this.

I think it will work out well. I just need to get too it.

Thanks!