D8R +463 in 1/5,6

[D8R]

Hi everyone, hope you have nice holidays!
Have not been so active with this Cat, but did get it running 3 months ago.
Found out that servos did not work as well as planned, felt like not having enough power (they should).
As you can see on link to vid bellow, that day model was only doing a left turn.

http://www.youtube.com/watch?v=psCaubtK4uo

Now I have new servos, got the holder cut only to get it together. But it's winter and have no warm garage to work in so have to wait (what is a couple of months, been building for 10+ years now).

Another problem is heat, engine getting to hot. Have tested removing noice damper inside homebuilt muffler, ended up mounting original silencer instead, hood and sides can not be on model with this muffler. Have to find another solution. Will try make a exhaust system without muffler to see if temperature gets lower.

And there's still some issues in hydraulic system. Can say that I was quite close to remove engine and hydraulic drive line, replacing it with electric motors. I know now that my size of model is as small as possible to build with this, components, tubing, hoses and all oil needed to get it running is just to much. A scale 1:5 should have been useful, every bit inside is used (of course cab could been used for oil and others but that's no option for me).

Some design errors made on homebuilt hydr cylinders has to be corrected to, but I'm supriced how good cylinders for blade turned out. Still more than 3 months since model was runned, blade is in air! That's tight cylinders, and weight of blade is almost 50 lbs.

Yes Jack, have all drawing saved on the model, but there will never be another made by me, just to many other interesting models to be built.

During the last months I have been active building some railroad stuffs, will post that in a seperate tread later.

Merry Christmas and a Happy New Year to you all!
Dan

[tc1cat]

Very nice dozer, to say the least!! Your issue with the motor may be not enough air flow over the motor to keep cool. Electric may be the best way to go. With your machining abilities, it should be no problem to make a drive system for the dozer. Ripper looks OK to me. Just needs to be pulled thru the dirt a few times and nobody will know its not yellow.

[D8R]

Originally Posted by tc1cat

Very nice dozer, to say the least!! Your issue with the motor may be not enough air flow over the motor to keep cool. Electric may be the best way to go. With your machining abilities, it should be no problem to make a drive system for the dozer. Ripper looks OK to me. Just needs to be pulled thru the dirt a few times and nobody will know its not yellow.

The Honda engine has a built-in fan that should keep engine cool. Have been thinking to add extra fan to get more air in-out of engine room.
Can't so much about engine (either), but if muffler don't let exhaust out easy I guess engine will have to fight harder to get mowing. Will test with new exhaust pipe.
Yes, yes, know wrong color on ripper but a soon model is up running good, all paint will be gone

[JAMMER]

Hi Dan Merry Christmas to you. Only a suggestion but you could try some computer fans under the hood to cool it and help remove exhaust gases. This is a very nice dozer and Big hope you get the kinks worked out so you can really enjoy using it. Ed

[D8R]

Originally Posted by JAMMER

Hi Dan Merry Christmas to you. Only a suggestion but you could try some computer fans under the hood to cool it and help remove exhaust gases. This is a very nice dozer and Big hope you get the kinks worked out so you can really enjoy using it. Ed

Yes Ed, have had same idea using such fan being powered from rc battery (have a large one and radio has voltage warning). Still think it's the homemade muffler causing the problem. A friend of mine installed a electric device that starts fan automatic when engine gets to a preset temperature.

Dan