Project of the Month built by mirek111

Help Support Home Model Engine Machinist by donating using the link above or becoming a Supporting Member.
Home Model Engine Machinist > Showing Them > Photos and Videos > Tiny I.C. Engine

Reply
 
Thread Tools
Old 03-07-2010, 02:04 AM   #71
putputman
Senior Member
 
putputman's Avatar
 
Join Date: Nov 2008
Location: Brainerd, MN. USA
Posts: 600
Liked 100 Times on 89 Posts
Likes Given: 18

Default Re: Tiny I.C. Engine

Gail, I checked my engine against the prints and found that I had cut the connecting rod down to .140 width. That gives it the necessary clearance.

I removed the print #8 rev B and replaced it with rev C. I think anyone that has got that far with the build can merely do as you suggested and norrow up the con-rod.

One thing I found with my engine is that the standard o-ring does not last very long. It may be that I don't have a highly polished cylinder bore but I think maybe it is more of a heat problem than a wear problem. The guy I buy my o-rings from ordered some Viton rings for me. They will stand 400 degrees vs the 200+ of standard rings. So far they seem to make the difference. I ended up with 30 of them. I will throw a few in an envelope & send them to you. I still have your address.

Greg, if you will PM me your mailing address, I will send some springs to you. I have quite a few of the very light ones. As I told you before they are light tension springs and I stretch them out to make compression springs out of them. Then cut them to length so that the free length and the compressed length is almost the same for the intake valve. You just need enough pressure to close the valve. The cylinder compression will seal it from leaking.



__________________
Regards
Arv
Brainerd, Minn. USA
******************
Think twice -- cut once ---- www.putputman.com
putputman is offline  
robcas631 Likes This 
Reply With Quote
Old 03-07-2010, 04:30 AM   #72
GailInNM
Administrator
HMEM_ADMIN.png
 
GailInNM's Avatar
 
Join Date: Feb 2008
Location: Albuquerque, NM, USA
Posts: 2,133
Liked 289 Times on 241 Posts
Likes Given: 112

Default Re: Tiny I.C. Engine

Thanks for the Viton O-rings, Arv. I have other sizes of Viton on hand, but was going to order some for this engine soon. I have a Buna-N (nitrile) installed in it right now, but I think you are right about the heat getting to Buna-N as Buna-N has better abrasion resistance.

For reference, Enco, MSC, and McMaster all have them in packages of 100 for about $10. My local seal shop also stocks a full line of them, but it would cost me $10 to drive over there to get them. On line ordering is normally the cheapest for me on most items as I live far from the industrial centers in Albuquerque.

Thanks for updating the prints. It will make it easier for the next guy to do a build.

Not much will get done on the Tiny for a few days. Have to go play games with the MD's on Monday morning and it will be late in the week before I can get back in the shop safely, although I will probably be on the computer again on Tuesday.

Gail in NM


__________________
Gail in New Mexico, USA
I would like to be the kind of person my dog thinks I am.
GailInNM is online now  
robcas631 Likes This 
Reply With Quote
Old 03-08-2010, 06:17 PM   #73
GailInNM
Administrator
HMEM_ADMIN.png
 
GailInNM's Avatar
 
Join Date: Feb 2008
Location: Albuquerque, NM, USA
Posts: 2,133
Liked 289 Times on 241 Posts
Likes Given: 112

Default Re: Tiny I.C. Engine

This morning's appointment delayed until after lunch so I have time to post a couple of photos of the previous parts put together. I decided that this engine will look better with a matt finish except for the brass flywheels which have polished rims. The head may get polished also after I look at it when it is built.
Gail in NM


__________________
Gail in New Mexico, USA
I would like to be the kind of person my dog thinks I am.
GailInNM is online now  
robcas631 Likes This 
Reply With Quote
Old 03-08-2010, 07:33 PM   #74
putputman
Senior Member
 
putputman's Avatar
 
Join Date: Nov 2008
Location: Brainerd, MN. USA
Posts: 600
Liked 100 Times on 89 Posts
Likes Given: 18

Default Re: Tiny I.C. Engine

That looks great Gail.

Are you going to run long studs from the head to the frame to hold the cylinder in place?

What have you decided for an ignition system?
__________________
Regards
Arv
Brainerd, Minn. USA
******************
Think twice -- cut once ---- www.putputman.com
putputman is offline  
robcas631 Likes This 
Reply With Quote
Old 03-09-2010, 09:05 AM   #75
NickG
 
Join Date: Jun 2008
Posts: 1,025
Liked 31 Times on 42 Posts

Default Re: Tiny I.C. Engine

Looking superb Gail I really like the design of this engine, looks a good one for beginners.

Nick
NickG is offline  
robcas631 Likes This 
Reply With Quote
Old 03-12-2010, 06:49 PM   #76
GailInNM
Administrator
HMEM_ADMIN.png
 
GailInNM's Avatar
 
Join Date: Feb 2008
Location: Albuquerque, NM, USA
Posts: 2,133
Liked 289 Times on 241 Posts
Likes Given: 112

Default Re: Tiny I.C. Engine

Thanks Arv and Nick.
Arv: Thanks for the care package of 0-rings. I am going to use the same ignition system that you used. I bought one a little while back to retrofit an engine I built about 8 or 10 years ago, but I have not gotten around to doing the retrofit yet. The cylinder will lbe held in place by three 2-56 x 1.5 SHCS, but I have to cut about 1/8 inch off. As usual I have two short and too long screws on hand.

I finally got back into the shop yesterday and got the head and standoff done. A few changes on each of course. Still the same operating geometry, but a few personal preferences thrown in.

On the head, I changed to 10-40 for the spark plug thread. I rotated the exhaust hole to come out horizontal and threaded it so I can screw in different exhaust systems. It is spotfaced for a locknut. The intake remained the same, but I did add two 0-80 threaded holes to hold a flanged mixer body in place with two 0-80 SHCS. The standoff hole is just a plain 3/32 drilled locating hole and the standoff is held in place by two 0-80 SHCS. All cosmetic and personal preference. It's still Arv's engine geometry with just a different look.

The standoff is flanged and held in place with two screws.
Gail in NM


__________________
Gail in New Mexico, USA
I would like to be the kind of person my dog thinks I am.
GailInNM is online now  
robcas631 Likes This 
Reply With Quote
Old 03-13-2010, 02:04 AM   #77
metalmad
Project of the Month Winner!!!
 
metalmad's Avatar
 
Join Date: Nov 2009
Location: Australia
Posts: 1,427
Liked 292 Times on 213 Posts
Likes Given: 26

Default Re: Tiny I.C. Engine

Hi putput
have just downloaded your plans to see if my poor eyesight will alow me to build one
hope so as it about time i started something new.
anyway 1K to U with thanks from the land of Oz
Cheers Pete


__________________
A little bit every day, sometimes the same little bit!

Skype - metalmad11
metalmad is offline  
robcas631 Likes This 
Reply With Quote
Old 03-13-2010, 02:41 PM   #78
putputman
Senior Member
 
putputman's Avatar
 
Join Date: Nov 2008
Location: Brainerd, MN. USA
Posts: 600
Liked 100 Times on 89 Posts
Likes Given: 18

Default Re: Tiny I.C. Engine

Gail, glad you received the package O.K. I have plenty more if you find you need more. So far I have started my engine several times every day & the o-rings are holding up good. The old buna-n rings would only work for a few days.

I like your stand off. It will give your engine some nice class. Can't wait to see your exhaust system.

I have 0-80 screws and a tap, but have never tried using it. I think 2-56 might be my limit.

Pete, I think you should go for it. From the conversations I have had with Gail, he has some serious handicap with his eyes also. It certainly doesn't show in his work though. Perhaps he can give you some tips on how to work with that handicap.

Look forward to following your build and will help in any way I can.
__________________
Regards
Arv
Brainerd, Minn. USA
******************
Think twice -- cut once ---- www.putputman.com
putputman is offline  
robcas631 Likes This 
Reply With Quote
Old 03-13-2010, 06:31 PM   #79
GailInNM
Administrator
HMEM_ADMIN.png
 
GailInNM's Avatar
 
Join Date: Feb 2008
Location: Albuquerque, NM, USA
Posts: 2,133
Liked 289 Times on 241 Posts
Likes Given: 112

Default Re: Tiny I.C. Engine

Pete,
Jump on in. Don't let not being able to see all the part details stop you. It may slow you down a bit, a lot sometimes, but if you have some engine building experience the "Tiny" is not too bad. I used some 0-80's because I have worked with them a lot over my life, but 2-56 is the smallest that Arv used on the basic design. And Arv, or I, will help you if you need and detail clarification on the plans. Besides, Arv would probably like for SOMEONE to actually follow his plans. I never was very good a following instructions.

Arv,
Thanks for the approval on the stand off. The flange was made separate and silver soldered to the post. For anyone who might be interested, the flange is rotated 15 degrees so I made the included angle on ends of the flange 30 degrees so it just is aligned to the flat side of the fork to braze up. I also drilled the holes in the flange a little bit oversize so I can rotate it a bit to align the rocker arm if necessary.

0-80's are not that bad. It's mostly feel. All tapping is done with a spring loaded driver in the mill to make sure the tap is perfectly in line with the hole. I use form taps, so no chips are made to bind up the tap. They are great for blind holes and I seldom use cutting taps except for larger sizes or special sizes. Hole size is more critical, and different, than for cutting taps is the only precaution.

I really like your idea of using the center electrode to support the PTFE insulator while machining. Never thought about doing that. I have a small rotating ball bearing tailstock chuck that I use to support long skinny parts while machining and it will work perfect for that. I am a little worried about drilling the very deep 1/32 hole in the spark plug insulator. My 1/32 drill bits only have .625 of flute so I guess that a lot so very fine peck drilling will be necessary to clear the chips. The drill bits are long enough so that is not a problem. I will find out soon enough.

The basic body for the spark plug is made, but other than the 0.079 hole being drilled through it I have not done any internal work. I am also making some copper washers to seal the spark plug. I just feel more comfortable with them in place to prevent leakage. OD of 0.265, ID of 0.190 and 0.029 thick. I cut some extra bodys and washers in case I ruin up a body. If I am lucky and don't mess up there are enough that some one can have one if they need it for a Tiny build and I will still have a spare.

No more work until tomorrow. Family get together in a couple of hours that will wipe out the rest of the day. It will be fun however with 3 of the 4 grandkids there.

Gail in NM


Gail in NM
__________________
Gail in New Mexico, USA
I would like to be the kind of person my dog thinks I am.
GailInNM is online now  
robcas631 Likes This 
Reply With Quote
Old 03-15-2010, 02:06 AM   #80
metalmad
Project of the Month Winner!!!
 
metalmad's Avatar
 
Join Date: Nov 2009
Location: Australia
Posts: 1,427
Liked 292 Times on 213 Posts
Likes Given: 26

Default Re: Tiny I.C. Engine

Hi gail and putput
i hope start getting some aliminium this week and make a start soon.
It will be fun to make I recon.
cheers from oz
Pete


__________________
A little bit every day, sometimes the same little bit!

Skype - metalmad11
metalmad is offline  
robcas631 Likes This 
Reply With Quote
Reply


Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Finished my version of Elmer's Tiny Engine TuxMan Finished Projects 8 08-17-2011 03:16 AM
My first Engine , frist Tiny and its a runner YAY! ewok Finished Projects 17 08-17-2011 03:04 AM
Teeny Tiny - My 3rd build Elmer's tiny at 1/2 scale 90LX_Notch Photos and Videos 19 03-29-2009 09:44 PM
Mighty yet tiny IC engine ! PTsideshow The Break Room 8 03-15-2009 10:19 PM
Elmer's Tiny - My 2nd Engine 90LX_Notch Photos and Videos 21 03-03-2009 03:16 AM



Newest Threads






- Top - Member List