Perry S.

OK, I'm tired of all my HL tanks not being able to turn under the heavy load of metal tracks and upgrades. Also tired of the race car scale speeds. So I designed new gearboxes. They are an exact size match for the HL units and will fit all the HL tanks. I was able to add one more 3:1 reduction gear (HL gear but will have to be modified). So this is 3:1 reduction gearbox from stock HL. 1/3 the rpm's and 3x the torque.
I also want to make a vacuformed cover that seals the GB from debris.

Now it's down to the shop to fabricate the sheet metal components.

shenlonco

My Feedback: (2)

All you really need to do is find a smaller pinion gear than the 10 tooth that's on it and just remout the motor.

Perry S.

you mean a 3 or 4 tooth pinion10 is the smallest they make for this size shaft.

shenlonco

My Feedback: (2)

Are you sure 10 is the smallest it looks kind of big for a pinion gear to me?.. I bet somebody makes a smaller one... heck i have found 48pitch 8 tooth pinions and that's on a big 540 motor shaft so it could be done easy on a smaller arm shaft.

Perry S.

I did a lot of searching. I think you can get 8T pinions for a 2mm micro shaft, maybe they exist for a 2.3 mm shaft. Still, 8T gives you a 50:1 reduction which would lower rpm and increase torques by only %20

shenlonco

My Feedback: (2)

Hi i looked at my mini T pinions they seem to be the same pitch you could drill out the hole bigger in them?
Also our gearbox is 40 to 1 with the 10 tooth....i don't know what the smallest pinion gears are they sell for mini T 280 sized motors is but it may work.

Perry S.

yes 40:1 stock with 10T pinion
8 tooth pinion yields 50:1

Perry S.

Here is my first 1:3 reduction prototype gearbox. It works incredibly well but I need to adjust the moter pinion to the right depth still. Gearbox so far is a perfect fit in my PIII but ti should fit all HL's. Just need to finsh off the cover and move on to the other gearbox.

darkith

Lookin good. Any thoughts on upgrading the final sprocket driveshaft will ball bearings for a more reliable output shaft? The steel & brass bushing always seems like such a weak point to me, but I haven't had my Heng Long for long enough to really know how long it'll last, either stock or with metal upgrades.

D.

Perry S.

I believe that the bushing on the driveshaft is of OK quality. Stress calculations show that it should hold but once I get these gearboxes working and driving hard in the field I will watch them. If they start to loosen up they will be fair game for a bearing swap.

BIGMIG

Man I would love to see your shop,you really get seriouse when you take on a project.How did you cut out the side plates,on a CNC mill or do you have a punch press.

Perry S.

It is actually pretty humble and I make up for it with creativity. Anyone can build these gearboxes with a dremel and a hand drill!
I made paper templates on my computer and taped them to some 1 mm steel from Home Depot. Drilled out the holes with a hand drill. Cut them to final shape with an air compressor and a cut-off wheel. A Dremel would work. Bent the pieces in a bench vise.

steenv

Hi Perry

Very nice work on the gearboxes. I am in for 2 x gearset for my HL tigers, if you decide to produce some for sale


Regards
Steen

BIGMIG

I wish I had half of your talent,I have a shop full of industrial machines and we sell them to guys with your talent to build things I can only wish I could do.Keep up the good work I am impressed with your ability.

pattoncommander

If you decide to make and sell these, I'm open for a couple sets.

Bill

Perry S.

In order to make this thing work I had to create a gear which is not stock HL. I cut up some old plastic HL gears and glued together the pieces. Filled in the gaps the bes I could with Tam putty. Then I made a silicone mold and cast the necessary gear. THis is the first time I have cast a part. The process was pretty easy. Now I have the gear.
Bought some new 10 and 15 tooth pinions which will allow me to set the gearboxes up as 2:1 or 3:1.

About selling them. Right now everything is hand made. The expensive part of the fabrication is the sheet metal. Sent the CAD data out for quote to 3 different places and the cheapest came back at $70 per gearbox for a run of 10 gearboxes. Volume discounts don't really kick in until the 1000's of parts range. I'm sure HL pays 4-5 cents for them. Oh to be in China and needing 100,000 parts[&o] So if I went that route it would cost me $200 just to make a set. I don't know, what would you guys be willing to pay? I imagine I would only be able to sell 20 sets so it's not really a get rich prospect

darkith

Nice cast! What do you cast the part out of???

D.

Perry S.

I rdered this from a company called Smooth-On
http://www.smoothonsecure.com/store/...44d9abc22f8f18
I really like the process and it was pretty easy. I thought after my S-100 conversion kit all these castings were crap but with a little care they yield excellent results. If you look through their stock they have aluminum filled resins for higher strength too.

johnmar78

Perry,,,I am impressed with your talent and patience. I better catch you before you off line.

I am sick of hl plastic gears, it ruined my enjoyment 2 years old after 2 tanks failed with metal tracks...pretty dumb ehh. SO I use tamiya gear box /tank too. But with the latest HL metal gear box...its better??? I have to wait my panzer !!! in action this weekned. time will tell.


I would prefer if you can make the gear box wall thicker so as the gears (wider) for better support. So the final diff does not grind all gears.

The cost you mentioned is true but may not practical for small orders(200US) each or for two?....

Even in australi, one gear made cost me 90$AS......or 45US.

For econimical reasons..I use tamiya gear box and paying around 110US dollars...each no offense to you but thats the fact.

Keep up with your work and I would be interested in 3:1 ADD on reduction kits for hl GBox. Let me know...

Thanks

Perry S.

I couldn't imagine wanting to pay more than $100 for both gearoxes with motors.

johnmar78

In that case, I am preparing to give it a go. So is that come with build in 3:1 reduction ?

Perry S.

I have pretty much finished the first gearbox. I still need to install the longer pinion. We'll see how long my resin gear holds up. It is possible to make this gear out of a stock HL metal gear but my spares are taking a while from Mato. I'm really happy with this one (it is about my 4th attempt). It runs silky smooth and it's reduction has to be seen in action.

swathdiver

Video! Video! Video! Show us that gearbox climbing a ladder in a Tiger chassis or something!

ksoc

Perry,

When looking for someone to produce you parts did you check out this site?

http://www.emachineshop.com/

Since I am on a Mac, I've never got to try their software, but the site looked interesting.

Perry S.

Kevin, that's a really cool site. I didn't try them but I tried 3 online sheetmetal prototyping services. They're in it for a business and I can't imagine any of them producing any order for under $300. It's just the nature of the game. At work, it means nothing to $1000 every couple of day for prototyping and most places cater to this because it's where the money is. Because of stoopid f'en ethics I won't make the on my work account.I need to find some old hobbiest dude that will make the sheetmetal for fun plus a few gearboxes in payment. Otherwards it pretty much dies here[sm=cry_smile.gif]