Mate diesel from Motor Boys plan book (long)

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quinette7 said:

I only randomly visit this site, but when I saw your post today, I just had to submit my first reply here.

Don't give up on your "Mate" Diesel! It will run! Mine did! - but not at first. It turned into a true learning experience.

Bob G


Welcome to HMEM Bob. Thanks for dropping by and giving Ariz a hand. I am sure that he appreciates it.

I notice that you have been a member for close to a year now and have your first post under your belt. With your experience I am sure that you will fit right in to many of the forums on the board. When you have a chance perhaps you could post some pictures of a couple of your engines that you have crafted over the years. It would be nice to leave an introductory post telling a bit about yourself in the "Welcome" section of HMEM. I look forward to seeing more posts from you in the future. :)

Cheers :)

Ariz -

I am sitting here admiring your helical knurls on the prop driver of your Mate Diesel. The knurls on my Mate don't look anywhere near that good. I'd like to emulate yours on my current MLA diesel construction. How did you do that?

Bob G
Hey there, just wondering if you ever got the mate and the other engine running?
I'm just doing exactly what you did: today I started to make another piston, because I suspect that most of the problems are there... lack of compression

To create tapered cylinder: Piston create tapered piston when the piston is lapped into the cylinder at final stage.
To test fit is correct: Dry piston/cylinder ---> tight to enter into cylinder. Oiled piston/ cylinder ---> The piston is loose fit in BDC cylinder and tight in TDC.

Lets take a look at a typical lapping job - that of producing a fine finished bore and piston for an IC engine. In fact, piston and bore are both lapped in separate operations (NOT both together). All of these operations will be carried out in the lathe (and I need hardly mention the importance of keeping lapping compounds off the machine, particularly the chuck and slideways). For the bore an expanding lap is ideal, and this should be some 3-4 times the total length of the bore. The first grade of abrasive would be mixed with light machine oil (10W or lighter) and liberally coated on the inside of the workpiece. Similarly, the slurry would be added to the outside (and inside assuming it is of the ventilated type) of the lap. The lathe would be started at about 300rpm (for a nominal 1" bore) and the lap passed rapidly through the bore, keeping it moving back and forth without it coming out the bore. How to hold the lap? well, perhaps the best way is with a 'floating' tailstock holder, and failing this holding with the hand is a method as good as any. Be careful when holding the lap by hand as it's possible it may jam, hold it lightly and expect the unexpected. Remember also that unless the lap is maintained dead parallel with the bore (an almost impossible task) it will tend to bell-mouth the bore a little - hence the reason for making the work a little longer than finished size and trimming to length later. When the inside of the bore has achieved an all-over grey appearance, with the fine scratches appearing even and criss-crossing both ways, and with no evidence of any deeper scratches (as might be left by the reamer) it's time to move onto the next finer grade. The work will have to be removed from the chuck to clean it properly, and this should be done with clean paraffin oil followed by hot soapy water. The same procedure applies to the lap and all traces of the abrasive must be removed. The process continues until you reach the 'flour' grade of abrasive by which time the finish on the workpiece should be very fine indeed. A final polished finish, should this be deemed necessary, can be achieved using metal polish (diluted Autosol, or some liquid chrome cleaner). The lap should be a separate 'finishing' lap so there is no chance of contamination with the coarser grades of abrasive which might be embedded in the main lap. The piston is treated in a similar way except of course the lap is female. Work will continue with the coarse abrasive until (using the un-trimmed bore as a gauge) the piston will not *quite* enter the bore. At this stage finer grade abrasives are used and work continues until the piston will just enter the bore tightly. At this stage, it is usual to finish mating the two parts by using metal polish and briefly using the piston to lap the bore directly. Great care needs be taken but this method ensures that the fit is good for the entire length of the bore.

About fuel, I had never had problem to use diesel from gas station in model diesel engine. The model diesel engine is not self igniting diesel by heat of compression. Also it is ether who is self ignited by heat of compression and then the main fuel such as diesel, kerosene, lamp oil or Jet-A1 will be ignited by ether in same time. Ether has self ignition about 188 degree celsious/370.4 Fahrenheit while the main fuel has high self ignition about 250 celsius/482 Fahrenheit.
If at first you don't succeed---then build a Webster i.c. engine. Just about everybody in the world has built one, they always manage to get them to run, and the plans are a free download off the internet. The Webster is a four cycle engine with valves, and there are about a billion well documented build threads on any forum you go to. I have built both two cycle and four cycle engines, and contrary to what makes sense, four cycle engines with valves and cams and all that tricky stuff are much easier to get running than two cycle engines which are about as simple as it gets.---Brian
hola chicos
aquí estamos de nuevo con un nuevo motor
No me gustan las premisas, pero aquí son necesarias pocas palabras.
Me gustaría documentar mis imágenes y publicarlas en la sección 'trabajo en progreso', pero descubrí que no puedo hacerlo por ahora: tengo poco tiempo para trabajar en el taller y sobre todo estoy demasiado cansado para tomar fotografías. subirlos y explicarlos
Para nosotros que no somos británicos ni hablamos inglés, no es tan fácil escribir artículos largos y llenos de explicaciones detalladas, especialmente por la noche, cuando uno está cansado después de un día de trabajo.
Navego por el foro a menudo y siempre es un placer, pero rara vez encuentro la energía para publicar e interactuar contigo, y esto es una gran preocupación para mí, especialmente cuando veo obras maestras admirables pero no encuentro las palabras para expresarlas.
afortunadamente existe la sección 'fotos y vídeo' donde puedo poner un breve resumen del build
hummm... Pido disculpas por la premisa, ¡no me gustan! ¿Ya lo había dicho?

Bueno, también lamento la calidad de las fotos: las tomé bajo una lámpara LED y están un poco oscuras.
a cambio, se enfatizaron muchos los defectos, tal vez por la luz tangente, efectivamente el motor no está tan mal

Este es mi cuarto motor y mi segundo motor IC.
Gané el POM en agosto de 2009 con mi segunda máquina de vapor, así que el año pasado construyó dos motores IC, los scuderi y este.
el scuderi todavía no corre ( :-\ ), espero que este tenga más suerte :D

Es el compañero diesel australiano de David Owen, y tomé los planos del 'libro de planos de motores modelo' publicado por los chicos del motor ( ), que compré hace algún tiempo.
bueno ahora las fotos...

el carter, aluminio




el cigueñal, acero



la cabeza y la placa posterior, de aluminio


el impulsor de biela y puntal (aluminio) y el tornillo de compresión, acero



Cilindro (acero), pistón y contrapistón, hierro fundido: el interior y el exterior del cilindro tienen peor aspecto de lo que son



esta foto de la cabeza es para mostrar lo que sucede cuando la rueda blanda que estás usando para pulir una pieza la atrapa y la dispara (pequeños carteles a las 9 - 10 en punto):semana:


la barra rociadora, de latón (aquí no soldada todavía)


Esta es la configuración para lapear el pistón, sugerida en el libro: muy efectiva.


Las fotos restantes son una secuencia del montaje.







bueno, ¿qué más?
Ahora construir necesito una fijación, algo para asegurar el motor al banco.
algún tipo de tanque para gasolina (por cierto, ¿qué tipo puedo usar para arrancar el motor?)
y una hélice... pero no pienso volar un avión con el motor, ¿puedo usar algo más en lugar de la hélice para arrancar el motor?
o necesito comprar una hélice porque no puedo construirla :-\

Eso es todo... Pido disculpas si hay demasiadas fotos en el post, espero que les gusten.

que planos usaste

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