Go to the hardware store and pick up a stepped drill bit and open that sucker up. I did this on my original motor mount and it looked great. Does a much nicer and cleaner job than a Dremel
Go to the hardware store and pick up a stepped drill bit and open that sucker up. I did this on my original motor mount and it looked great. Does a much nicer and cleaner job than a Dremel
View attachment 241969
First thing I'm noticing is that the shaft of your motor is definitely longer than the one on mine. My rotor was a replacement for an original 5mm that snapped. It never occured to me that they may have sent a rotor for a slightly shorter can. If the shaft on my rotor was as long as what I'm seeing here, I could have easily flipped the pinion and had room for the set screw to seat. FML
You're not wrong, but on my plate I found that if I step drilled it right up to the edge of the chamfer that the shoulder of an 8mm pinion would fit without rubbing. One thing to look out for is to make sure to use short enough grub screws that don't protrude outside of the pinion shoulder. Is it as neat as having the correct plate? No. But it does work. I suppose the argument against it might be that there aren't terribly many motors that have both a 25mm bolt pattern and an 8mm shaft. The TP 4080 and CC 1721 come to mind and I think you can get the 4070 with an 8mm shaft now. The 56 plate obviously wouldn't work for any of these motors.
I have a set, but I'm pretty sure the largest one isn't big enough. Great idea though. I think boring out the hole is the best option for now. I'm not convinced that moving the pinion on the spool was the best idea, but I guess I won't know until I make a few passes.Go to the hardware store and pick up a stepped drill bit and open that sucker up. I did this on my original motor mount and it looked great. Does a much nicer and cleaner job than a Dremel
View attachment 241969
TP has different length shafts (the part that protrudes outside the can I mean). My 4080 has a 30mm shaft, my 5680 has a 20mm shaft (I wasn't paying attention and just assumed it had a 30mm shaft also). It's a bit annoying but it's mitigated by the Joe Diaz spool which doesn't require spacers as it has shoulders that the bearings sit on so you can just position the spur wherever you like on the spool shaft.
So there's an optional slide with wider spacing for bigger cans, but probably won't work on my 4070 2250, even though it has an 8mm shaft. FML x 2
With the motor assembled, try and tap the rear side of the shaft and see if it will slide out the front a little more. Don’t wail at it with a ton of force but just little taps with a small hammer and punch. I’ve had to do this to my 4050 when the 5mm shaft snapped off a small bit. Was able to push the shaft thru the rotor enough to get a pinion on. Doing this with the motor assembled ensures you don’t go too far.
Mine is a 4070, and I do believe the shaft is shorter. I just went on the Arrma site and realized they have four different sliders. a 40, 50 and 56. I believe the stock kit uses the 50. I also noticed that Arrma offers a bunch of 8mm pinions. Is it possible that the pinions they make will fit the 50 series slide? Possible that they have a smaller circumfrence where the set screws attach compared to the Saga ones I currently have.
I actually took the motor apart last night to clean and oil the bearings. There is probably only ~2mm of play in total. I think my only solution is to bore out the hole on the slide as much as possible, or find out if those Arrma pinions will work with the 50 series stock.
I mitigated that problem by using 8mm id x 10mm od shims. They're perfect for keeping bearings off the pinion.
What about running a larger spur?
Did Arrma just recently start making 8mm pinions? I have a few of their spur/spool gears and they have a 15.8mm shoulder which is roughly equivalent to the shoulder on 8mm SAGA gears. I'd be a little surprised if the 8mm pinions from Arrma had a thinner shoulder.
They have 8mm pinions, but there's no spec on the shoulder size (surprise surprise) They all start with ARA3111 folowed by 20 to 27 ie: Ara311120 is a 32 tooth mod 1, 21 is 33t and so on. Available on Horizon's site, but none of my lhs have them yet. I'd buy one just to test fit, but I don't like the idea of paying shipping from the US just to find out.
Yeah, I feel ya. Shipping would probably cost as much as the item...maybe more. I bought a pair of tail lights from Polo Creations for $12. Shipping was $36. Granted, I'm in Germany but that's just obscene.
I'm attempting to do that now with some SAGA pinions I just ordered.
Agreed on option #1. I think in that case it would probably be best to use a grub with a pointed tip.
Funny you bring up the flat part of the pool. Last night, that was one of the modifications I made on mine. I used a Dremel to grind out a slighly larger are of flat so that I could reverse the stock spool gear and have a place for the set screw to seat. Was it a hack? Sure was, but I'm going to get that damn car running if it means chopping every thing in it to make it work with what I have. For the record, I had to drill out the cross pin head because of red loctite. The spur is only being held on by one set screw as both openings at 180 are threaded on the Arrma pinions. I used a small enough bit that I didn't wreck the threads in the first hole, but I can't figure out how to remove the remaing metal that was left in the hole. Does anyone else see how bad this is going? I think it's time I take up needle point, but I'd probably still end up stabbing myself.
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