Building an Ohlsson & Rice test mount

Seeing that makes one wonder. If it does not fit a commercial test mount, how does one mount it to a plane????

I have two test stands, one being a Tatone and the other a EZ-Just. The O&R's fit both. Neither of these stands were offered until 20 years later. The O&R protrudes a fair amount from the bottom of it's lugs. K&B essentially did the same with their early Torpedo's. In 1948 Duke Fox offered the sand cast Fox .35. The same year the glow plug was offered. He made the lug spacing, length and width the same as the O&R. He did this for a specific reason and it pretty much worked. You now have a engine with twice the power, no batteries, coils, condenser to haul around. This was reason enough not to buy the O&R engines and directly swap his units into.

Most planes that utilized O&R's used full bodies to facilitate the electronics and battery case. The front was generally wide allowing the case to hang down unseen with the cylinder sticking up. These are well before my time but they don't offer much power. Whenever I've seen them in use, it's always been a timid flyer such as a freeflight. model.

I couldn't get my .29 to fit on either Ken, but I have the small Tatone.

About ready to fuel this thing up.  Hooked up a temporary bracket and hot melted it on to the mount and the tank too hoping to reduce vibrations should this thing actually run.  



Glow plug is bad so I replaced it.  I have no idea as to the heat range or which one the O&R would require.  Cut and try.




Anyone ever think about making a display of vintage glow plugs?  I have been mulling it over.  Vertical with a mirror behind a drilled piece of Mahogany, or milled out horizontal at a slight up angle.



Note to self - Next time do not put thumb in hot melt glue.......

Use the hottest plug you have. These engines need lots of oil, oil = HOT. If you have a 6 pitch prop similar to what you have it will keep a better load on the engine. These don't generally like high rpm's.

The Arden plug you show in the pic ( Big ball top) is the period correct plug and is a good choice if it lights.

I'm not familiar with these O&R engines, so I did a little research. Found an old thread (2012) right here on the forum. One contributor mentioned that the glow versions (remove the sparker mech and the plug) like 0% nitro and that they might have used Veco needle assemblies. So, I did wrong.

Secured the tank and using the filler blub from yesterdays excursion with the K&B filled it with Cox 25% before I noticed. Sucked some of it out and replaced with Traxx 10%. Primed it and first flip got a weak flutter of about four revolutions before it quit at about four turns out. Fooled around that setting getting strong runs of five or six revs and that's it, plenty of fire and strong fuel draw. Quit after last flip caught the back of my finger. Ouch.

I'm sure it will run, but what's the sense. Hate to give up, but it's not one of my two or three flip Enya's.

Running a O&R on 5-10% nitro is highly recommended. I don't putz with FAI  no nitro fuel, my engines have too low of compression to make that fuel work. Unless your Traxxas fuel has oil added to it, I wouldn't recommend running the O&R on it. The O&R needs 25-29% all castor fuel. The O&R has a needle bearing thrust washer in  it's bottom end that will probably not tolerate low oil content fuels.

           The only O&R's that I've ever witnessed blow their tops was the .60. The cylinders are spot welded on and when they let go, the just blows off of the top.

If you back flip the prop, you absolutely can't get hit in the finger. Most engines start easier this way and it's the only way to start a flooded engine.

It will start Ken, just will not keep running.  Act's lean, but a a turn or two rich doesn't make much difference.  In defense of it, I haven't even removed the needle to wipe it off or clean the spray bar.  Guess I will do that, then try some back flips and maybe try one of those old plugs.

Hot melt glue gave up on the bracket, didn't separate completely, but I still had to mechanically attach it with a screw.  Tank is holding well.

Poor hunk of 2X4 has seen at least two gun racks in addition to that fuel tank mount.  Before that I don't know.  Has more holes in it than swiss cheese.  Eager to trim it up some into a display mount for that O&R.



Looking for my .23 I found this little devil. Rear induction, weird plug, but I have two new cards of them. No NV when I got it, replaced with an Enya.

Hello Bob , see your having some O&R Fun , after all the trouble to get it turning over and the cleaning involved I can't believe you didn't do this >> (In defense of it, I haven't even removed the needle to wipe it off or clean the spray bar. Guess I will do that,)) I think it will run after a good cleaning of the holes ... Good luck and bee careful with that noise maker