Bonza hit and miss engine designed by John Williams

[AussieJimG]

Press on Greg! The really hard work was done by John Williams, the original designer; all I did was to modify the engine to suit my limited abilities and re-do the drawings in Alibre.

Speaking of Alibre: I have posted a CD with all the Alibre files in it. It really is the easiest way to do the Imperial conversion (I know from doing several the other way). The thing that will get you is the thread conversions but that is simple too - just edit the holes and change the thread specification and it is all done.

I am looking forward to seeing the finished conversion. And, of course, the build log.

Jim

 

[AussieJimG]

Ian, Lonnie, Jim the drawing files (complete with Greg's amendments) have been sent. I know some of you have received them.

I am now looking forward to seeing some build logs to brighten my day.

Thanks all of you for your interest.

Jim

 

[AussieJimG]

The lines are running hot. Jim, Bertil, Ken and Leonard should now have the drawings.

This is getting exciting.

Jim

 

[GKNIPP]

Hey there Jim, I am almost affraid to say this for fear of upsetting you, but, I found a few more dimensions and features omitted on the original plans. Do you want me to just send you an e-mail with the errors as I find them or just wait until I think everything has been addressed?

I hate to bother you, but, I guess I am trying to help work out some of the bugs and make things easier for the other gentleman to work with. I hope you don't mind.

Greg

 

[AussieJimG]

Far from being upset Greg, I am very grateful to you for going through the drawings in such detail. It is almost impossible to pick up those errors oneself and I feel bad about sending out stuff that is not correct.

I would be happy for you to post the problems here as you find them and that way the other people to whom I have sent plans can see and either correct them or ask for an amendment.

So press on my friend, and let it all hang out.

Regards

Jim

 

[Jeff-in-PA]

I PM,d about a set of plans too. Thanks

Cheers
Jeff

 

[GKNIPP]

With your blessings Jim I will begin to post as I find errors, missing features/dimensions etc....

Sheet #4 "Rear Plate",----- Should there be a relief or cut-out to allow for clearance of connecting rod ?

Sheet #5 "Governor Side Plate",----- The upper hole feature located towards bearing block cut-out missing dia./thread size.

Sheet #6 " Ignition Side Plate" , ----- The hole for cam gear shaft is marked as 3X and should be only 1X. Should the X&Y dimensions for this hole location be given using the crank center as datum by the utilization of the pitch dias. of gears for proper mesh?

Sheet #7 "Crankshaft"------ Missing center distance of crank throw from main shaft dia. and hidden line indicating the crank throw dia.

Sheet #18 "Exhaust Rocker"------Missing "L" shaped finger depth dimension from centerline of part to tip of R4.

Sheet #19 "60T gear & 30T gear"------ Is it possible to list the root diameters, outer diameters and pitch circle diameters of specified gears.

Again Jim, Please do not look at this as me being a pain but rather trying to be helpful. I am sure I can speak for the rest of the guys that your work is well appreciated.

This is all for now. My wife suggests we get some supper now.

Regards my friend;

Greg

 

[AussieJimG]

Thanks Greg, you are doing a great job. I will fix the drawings today. I am sorry I made it so hard for you.

Jim

 

[GKNIPP]

Not hard at all. It is easy enough to do, in fact, I can't guarantee I didn't overlook something but I hope not. It is just greatly appreciated that you took the initiative to share a design with us as you did the hard work.

Sheet #21 "Valve Rod"----- Thread length dimensions missing at each end of rod.

Sheet #22 "Flywheel Center"------ Add note suggesting to install bolt hole pattern in cenetr after assembled so as to insure proper orientation of mating part #80, governor plate, to position weight arm BETWEEN spoke of flywheel assembly.

Sheet #24 "Governor Adjuster" ----- I believe the 10mm center hole should be indicated as a 10mmx1.0 thread?


Well, I think that is about all I can detect for now. Now comes the fun part!!!! C O N V E R S I O N!!!!!!!!!

Thanks Jim;

Greg

 

[GKNIPP]

Jim, I do notice that the drawing set does not include the following parts:

-No Carburator Parts---- #110, #111,

-No Oiler Parts---- #119, #120, #121, #122, #123, #124

-No Grease Cup Parts----#117, #118

-No Muffler Parts----#106, #107, #108, #109

See I told you I would overlook things too. I realize the oilers and grease cups coulds easily be purchased and the if the modeler chose to do so he would need to adapt the engine parts to suit.

Greg

 

[AussieJimG]

Hi Greg, I finished amending and adding drawings after a long day yesterday and opened my email this morning in fear and trepidation (not really) but there were no more errors (?).

Just a couple of things: Sheet 4 Rear plate cutout. There was one on the original and I put one on mine to accommodate an oiler on the big end bearing cap. But my engine kept snapping the oiler off and throwing it across the workshop (never did find one of them). Then I found that there is so much oil splashed around from the piston that the big end seems to be adequately lubricated anyway. So I omitted the oiler. The conrod does not touch the end plate so that is not a problem. The cutout could be included for cosmetic purposes if required but I think the blank end might stop some of the oil being thrown so far.

Sheet 19 Gears. I could not find the root diameter for the gears. I think anybody making the gears will be able to obtain the dimensions from the specifications. Outside diameter and Pitch diameter were added as requested.

Sheet 21 Valve rod. The little down arrow is intended to indicate the length of the thread. I tried to add an explicit dimension but it didn't "take". Sorry about that.

I have sent you a set of all the updated drawings.

Bertil, BC1, Ian, Ken, Lonnie, I have also sent the updated drawings to you. Please let me know if they arrive safely.

Cogsy, drawings have been sent but they have overloaded your inbox. Let me know what did not arrive and I will send it again.

Leonard, CD going in the post today with complete set of updated drawings and other stuff as requested.

Once again Greg, thank you for all your efforts. I am astonished at how much I had left out. And good luck with the conversion.

Anyone else need the updated drawings?

Jim

 

[ozzie46]

I'd Like a set too please. PM sent.

Ron

 

[bearcar1]

Drawing updates arrived this afternoon in good fashion Jim, thank-you for keeping me(us) in mind. I've sent you a private email as well. All the new pages have been accounted for and replaced in my files, along with the addendum sheet for future references. Well done.

BC1
Jim

 

[AussieJimG]

Jim (BC1) has noticed that Sheet 24 is still Revision 1 and does not show the thread on Item 99. Thanks Jim dunno how I missed that but it is now fixed in the drawings and in the amendment sheet.

Would you and the rest of you to whom I sent the amendment sheet please hand amend Sheet 24 to show Item 99 with an M10x1.0 thread in the central hole and change the revision to 2.

And Cogsy and Leonard (who got the works) please do likewise.

Ron (ozzie46) yours should be ok when they arrive.

And other problems, please let me know. We might as well get it right.

Regards

Jim

 

[aarggh]

Hi Jim,

I got the updated drawings thanks very much! And thanks to Greg too for his valuable input!

cheers, Ian

 

[Cogsy]

Cogsy, drawings have been sent but they have overloaded your inbox. Let me know what did not arrive and I will send it again.

Thanks Jim, I got everything except the sheets 21-31. Looks great too Thm:

 

[ozzie46]

I want to publicly thank Jim for the drawings. I received all of them.

Thanks Jim.

Ron

 

[AussieJimG]

Last file (Sheets 21-31) is on its way Cogsy

Thanks everyone for your interest.

Jim

 

[GKNIPP]

Once I get these converted, I am going to need to harness someones abilities to transfer the dimensions onto the CAD prints.

BTW, where do you guys go to purchase gears? I used to have a suppliers list but cannot locate it at this time.

Thanks to everyone for your patience;

Greg

 

[AussieJimG]

Is anybody still waiting for copies of the drawings?

Jim