1/8 th scale hydros
01-11-2010, 12:38 PM
#51
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Location: brownsville,
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RE: 1/8 th scale hydros
Thanks JP,
Makes perfect sense and I'll do that then...I was going to order some race bearings from mecoa however I'm not quite 100% sure of the size that Ineed. What I have is an older k&b sport marine engine (6.5cc/side exhaust) that came with a Perry carb. Its in pieces right now & I cleaned up the piston and cylinder with 000 steel wool along with the case inside & out. The piston and liner look like it was used very little, practally new looking, along with the cylinder head...
Has anyone ever used a tumbler (for reloading ammo) to polish up parts & engine caes?
Makes perfect sense and I'll do that then...I was going to order some race bearings from mecoa however I'm not quite 100% sure of the size that Ineed. What I have is an older k&b sport marine engine (6.5cc/side exhaust) that came with a Perry carb. Its in pieces right now & I cleaned up the piston and cylinder with 000 steel wool along with the case inside & out. The piston and liner look like it was used very little, practally new looking, along with the cylinder head...
Has anyone ever used a tumbler (for reloading ammo) to polish up parts & engine caes?
02-13-2010, 09:36 AM
#52
Thread Starter
RE: 1/8 th scale hydros
Wow thats a pretty early k&b I havent seen the old fence style piston in a long time, as I remember they were real torquey but lacked in the rpm capabilities, maybe use a bigger pitch prop & cup the tips a little at a time till you find it's sweet point..... good luck and I'll be wachin.
02-13-2010, 06:57 PM
#53
RE: 1/8 th scale hydros
I know that walnut shell medium you can buy for a sand blast cabinet will put a mirror shine on aluminum even in the corners.
I would have to think each part to decide if the tumbler idea would be a good one or not. I guess backplates would be okay, maybe a crankcase but not the head or the front intake where there's bearing fits, close tolerance machining or sharp edges that are meant to stay sharp.
Grit blasting I don't like because you can never be sure all of the grit is out of the aluminum. If I were to use grit or sand or bead blasting I would assemble the empty cases first and blast it as an assembly, then take it apart and clean it ultrasonically.
I think just going around each machined edge checked with a file or stone and some steel wool to smooth that out is a good start and basically all an engine needs to be safely put together again. Anything past that I would say is extra but worth it. Not sure if I would want to drop in nothing less than a clean rebuilt engine in a new hull. Thats always a good goal to have
F16 mentioned something I'll be fighting a bit with the early Webra's which have the same character as RJ's. These I have are primarily all alky engines. They don't like nitro not even to idle some of them like the early baffled piston. They develop some good power and to use it you have to make up for it in prop diameter. Not necessarily the best path sometimes because of torque effects on handling but using a smaller prop and fine tuning it up to the power curve you can try and sneak by.
I would have to think each part to decide if the tumbler idea would be a good one or not. I guess backplates would be okay, maybe a crankcase but not the head or the front intake where there's bearing fits, close tolerance machining or sharp edges that are meant to stay sharp.
Grit blasting I don't like because you can never be sure all of the grit is out of the aluminum. If I were to use grit or sand or bead blasting I would assemble the empty cases first and blast it as an assembly, then take it apart and clean it ultrasonically.
I think just going around each machined edge checked with a file or stone and some steel wool to smooth that out is a good start and basically all an engine needs to be safely put together again. Anything past that I would say is extra but worth it. Not sure if I would want to drop in nothing less than a clean rebuilt engine in a new hull. Thats always a good goal to have
F16 mentioned something I'll be fighting a bit with the early Webra's which have the same character as RJ's. These I have are primarily all alky engines. They don't like nitro not even to idle some of them like the early baffled piston. They develop some good power and to use it you have to make up for it in prop diameter. Not necessarily the best path sometimes because of torque effects on handling but using a smaller prop and fine tuning it up to the power curve you can try and sneak by.
01-13-2016, 01:45 AM
#56
I've always got something on the bench. The issue is getting the time to work on them. My bench, right now anyway, has the following under construction:
1/8th scale 1973 Pay'N Pak
1/8th scale 1985 Executone
1/8th scale 2000 Elam Plus to replace the 15 year old hull I've run for the past few years
1/8th scale 2009 Oberto
1/6.7 scale gas 1978 Madison
3 sport 20 boats, 3 sport 40 boats
You can add to that a scale Steve Muck 1978 Circus Circus that I'm restoring
On top of these, waiting in the wings, I have two "sorta scale" Dumas Circus Circus builds(one kit and two cowl sets) and a Dumas Eagle sport 40
If that's not enough, I also have a Sig Kadet Jr started and FOUR 50cc gas aerobatic planes waiting to be built
I figure, when I get some spare time, I should be able to get them all built and running
1/8th scale 1973 Pay'N Pak
1/8th scale 1985 Executone
1/8th scale 2000 Elam Plus to replace the 15 year old hull I've run for the past few years
1/8th scale 2009 Oberto
1/6.7 scale gas 1978 Madison
3 sport 20 boats, 3 sport 40 boats
You can add to that a scale Steve Muck 1978 Circus Circus that I'm restoring
On top of these, waiting in the wings, I have two "sorta scale" Dumas Circus Circus builds(one kit and two cowl sets) and a Dumas Eagle sport 40
If that's not enough, I also have a Sig Kadet Jr started and FOUR 50cc gas aerobatic planes waiting to be built
I figure, when I get some spare time, I should be able to get them all built and running
Last edited by Hydro Junkie; 01-13-2016 at 02:11 AM.
01-13-2016, 09:32 AM
#57
Thread Starter
OK then,,,,,, let's see what year were you born so I can figure out if you could finish all that ha ha , I did not know that you came over to the dark side of air planes,,,, you will have to hook up with Karl Hibbs up there in your neck of the woods, probably one of the most talented pilots in this country that I've ever seen.........................
