Notices
Glow Engines Discuss RC glow engines

Welcome to Club SAITO !

Old 12-12-2021, 08:41 PM
  #51651  
Jesse Open
 
Jesse Open's Avatar
 
Join Date: Mar 2018
Location: 30 Miles North of Canada Border
Posts: 3,788
Received 92 Likes on 84 Posts
Default

Real valve seat grinders are lifted during the cut repeatedly to interrupt the cut and avoid plowing the ditches. Likewise, proper lapping involves short, alternating back and forth strokes, also with frequent lifting.


Angular, fluted reamer-like cutters may be used instead of grinders. Whe major cuts are made, the top and throat area are re-cut to un- mask the pocketed top and provide a seat of constant, concentric width.

These toy engine seats are already pretty crude right out of the box !
Old 12-12-2021, 09:14 PM
  #51652  
the Wasp
My Feedback: (1)
 
Join Date: Sep 2003
Location: VT
Posts: 5,389
Likes: 0
Received 41 Likes on 39 Posts
Default

any one know what this home made tool is ? LOL guess LOL
it is 5 inches long and made with 10 magnets I had just setting around. each magnet is 3/8x1/2 inch. these are very strong magnets, they even work threw my finger LOL. I guess you could make this tool with only one magnet if you had a metal handle for it. but for some small valves you will need to turn down the magnet's OD on a lathe. or find magnets with a smaller OD.
if you LOL figure out what it is for don't tell the OS guys LOL

Jim


Last edited by the Wasp; 12-13-2021 at 08:47 PM.
Old 12-12-2021, 09:31 PM
  #51653  
the Wasp
My Feedback: (1)
 
Join Date: Sep 2003
Location: VT
Posts: 5,389
Likes: 0
Received 41 Likes on 39 Posts
Default

Originally Posted by Jesse Open
Real valve seat grinders are lifted during the cut repeatedly to interrupt the cut and avoid plowing the ditches. Likewise, proper lapping involves short, alternating back and forth strokes, also with frequent lifting.


Angular, fluted reamer-like cutters may be used instead of grinders. Whe major cuts are made, the top and throat area are re-cut to un- mask the pocketed top and provide a seat of constant, concentric width.

These toy engine seats are already pretty crude right out of the box !
did that!
Jim
Old 12-13-2021, 04:09 AM
  #51654  
Jesse Open
 
Jesse Open's Avatar
 
Join Date: Mar 2018
Location: 30 Miles North of Canada Border
Posts: 3,788
Received 92 Likes on 84 Posts
Default

This too?


"Angular, fluted reamer-like cutters may be used instead of grinders. Whe major cuts are made, the top and throat area are re-cut to un- mask the pocketed top and provide a seat of constant, concentric width."
Old 12-13-2021, 06:45 AM
  #51655  
1200SportsterRider
Senior Member
 
1200SportsterRider's Avatar
 
Join Date: Dec 2019
Location: Virginia
Posts: 1,140
Likes: 0
Received 35 Likes on 35 Posts
Default

The black Saito 150 rebuild is this far along, new Boca's installed, new RMJ ring coming, good used cam and followers installed. The cam box is in the picture in case someone needs one that takes the followers without the mushroom heads, the cam box is for an early 120?, designation unknown to me.
I hope the scribe or otherwise write 150-S on the red patch. I'm still thinkin on it.

Old 12-13-2021, 07:04 AM
  #51656  
Jesse Open
 
Jesse Open's Avatar
 
Join Date: Mar 2018
Location: 30 Miles North of Canada Border
Posts: 3,788
Received 92 Likes on 84 Posts
Default

Dave, I believe that cam box is from a FatHead Saito
The red tag, if you like, can be lifted after heating with a soldering gun. You could make a custom, brass tag (?)


Jim , Forgot to add those micro pics were outstanding. Good effort on saving the cylinder too. The comments were hopefully a bit helpful.

Last edited by Jesse Open; 12-13-2021 at 07:11 AM.
Old 12-13-2021, 07:08 AM
  #51657  
1200SportsterRider
Senior Member
 
1200SportsterRider's Avatar
 
Join Date: Dec 2019
Location: Virginia
Posts: 1,140
Likes: 0
Received 35 Likes on 35 Posts
Default

Thanks Gary, I found the tappets for that housing at MacGregor's, more later on the tag.
Old 12-13-2021, 07:31 AM
  #51658  
Jesse Open
 
Jesse Open's Avatar
 
Join Date: Mar 2018
Location: 30 Miles North of Canada Border
Posts: 3,788
Received 92 Likes on 84 Posts
Default

Originally Posted by 1200SportsterRider
Thanks Gary, I found the tappets for that housing at MacGregor's, more later on the tag.
Looking forward to a pic of the completed engine!
Old 12-13-2021, 08:19 AM
  #51659  
FlyerInOKC
My Feedback: (6)
 
FlyerInOKC's Avatar
 
Join Date: Nov 2004
Location: Oklahoma City, OK
Posts: 14,167
Received 275 Likes on 240 Posts
Default

Originally Posted by Jesse Open
Looking forward to a pic of the completed engine!
Same here!
Old 12-13-2021, 08:19 PM
  #51660  
the Wasp
My Feedback: (1)
 
Join Date: Sep 2003
Location: VT
Posts: 5,389
Likes: 0
Received 41 Likes on 39 Posts
Default

Originally Posted by Jesse Open
This too?


"Angular, fluted reamer-like cutters may be used instead of grinders. Whe major cuts are made, the top and throat area are re-cut to un- mask the pocketed top and provide a seat of constant, concentric width."

yes I read that
Jim
Old 12-14-2021, 03:41 AM
  #51661  
1200SportsterRider
Senior Member
 
1200SportsterRider's Avatar
 
Join Date: Dec 2019
Location: Virginia
Posts: 1,140
Likes: 0
Received 35 Likes on 35 Posts
Default

I was about to order an RMJ ring for the 150, there is a choice of ring thicknesses, so I have to measure the ring. https://rmjmachineworx.com/online-st...s/saito-fa-150

The choices, .039" and .0585", I checked and the 300 offers the same choice.



Last edited by 1200SportsterRider; 12-14-2021 at 04:28 AM. Reason: Add picture
Old 12-14-2021, 04:45 AM
  #51662  
Glowgeek
 
Join Date: Feb 2016
Posts: 3,617
Received 65 Likes on 65 Posts
Default

Your right Dave, RJM does offer two different ring thicknesses. Weird.

The 150 is a strange animal, some lower compression and some higher but with no readily visual differences in the cylinder, piston or rod. At one point we were going to figure that out with measurements but never really nailed it down. As I recall you had one marked "A" and I had one marked "K" but both were high compression units.

I sold my 150 and replaced it with the same sized case, only slightly heavier, but way more powerful 180. That 180 has recently been converted to gas. Final bench testing commencing sometime over the next week.

For those interested in the DIY glow to gas fuel control system I'm implementing details can be found here: https://www.rcgroups.com/forums/show...ecommendations

Last edited by Glowgeek; 12-14-2021 at 04:51 AM.
Old 12-14-2021, 05:37 AM
  #51663  
Jesse Open
 
Jesse Open's Avatar
 
Join Date: Mar 2018
Location: 30 Miles North of Canada Border
Posts: 3,788
Received 92 Likes on 84 Posts
Default

Originally Posted by the Wasp
yes I read that
Jim


Were you able to trim the seat to a consistent width?
Old 12-14-2021, 06:31 PM
  #51664  
Glowgeek
 
Join Date: Feb 2016
Posts: 3,617
Received 65 Likes on 65 Posts
Default

Originally Posted by 1200SportsterRider
I was about to order an RMJ ring for the 150, there is a choice of ring thicknesses, so I have to measure the ring. https://rmjmachineworx.com/online-st...s/saito-fa-150

The choices, .039" and .0585", I checked and the 300 offers the same choice.

Looks to measure .0575", even with the crusty carbon. It's seen some run time.
Old 12-14-2021, 08:59 PM
  #51665  
the Wasp
My Feedback: (1)
 
Join Date: Sep 2003
Location: VT
Posts: 5,389
Likes: 0
Received 41 Likes on 39 Posts
Default

Originally Posted by Jesse Open
Were you able to trim the seat to a consistent width?
Gary, go back and look at the Pics, it is imposable to get that seat width consistent with only a valve to work with. even Saito with all their tooling didn't get it correct. and to add, as I said nothing is at a 90 degree so the valve face is not level to the celling. not my fault. it all shows it in the pics.

Jim

Last edited by the Wasp; 12-15-2021 at 01:07 AM.
Old 12-15-2021, 01:13 AM
  #51666  
the Wasp
My Feedback: (1)
 
Join Date: Sep 2003
Location: VT
Posts: 5,389
Likes: 0
Received 41 Likes on 39 Posts
Default

Originally Posted by esmithga
The Wasp,

Very cool.

I have an FA-60T with a leaky exhaust valve that I can't get to seat. I'll try your method when I am able,
Thanks for the idea,
Evan
good luck, just know if it fails the cylinder will most likely be worthless. and if it works you should do both sides on a twin

Jim
Old 12-15-2021, 01:46 AM
  #51667  
Glowgeek
 
Join Date: Feb 2016
Posts: 3,617
Received 65 Likes on 65 Posts
Default

Originally Posted by esmithga
The Wasp,

Very cool.

I have an FA-60T with a leaky exhaust valve that I can't get to seat. I'll try your method when I am able,

Thanks for the idea,

Evan
Likewise, I had an exhaust valve that wouldn't seat on a 60T. In my case the valve guide was worn beyond serviceability. All the lapping, grinding or cutting in the world wasn't going to help. The only fix would have been to replace the valve guide, not something I have tooling for.

Typically I find valve guides in good shape on used Saitos, even high runtime ones, but that was not the case with my 60T sample. I believe that the previous owner may have used lapping compound at some point and failed to clean it out thoroughly before running the engine. Just a guess but I can't see any other way where only one of four guides was worn out on such a low run time engine.

Old 12-15-2021, 03:59 AM
  #51668  
1200SportsterRider
Senior Member
 
1200SportsterRider's Avatar
 
Join Date: Dec 2019
Location: Virginia
Posts: 1,140
Likes: 0
Received 35 Likes on 35 Posts
Default

I just checked and neither the 180 nor the 2.20 offer a choice in ring widths. To satisfy my own curiosity Ill measure both today.
Old 12-15-2021, 06:47 AM
  #51669  
Jesse Open
 
Jesse Open's Avatar
 
Join Date: Mar 2018
Location: 30 Miles North of Canada Border
Posts: 3,788
Received 92 Likes on 84 Posts
Default

I have seen several Saito guides that were made sloppy at disassembly. During operation with sloppy rocker clearances, the valve tips become peened into a slighy mushroom shape. Forcing those valves out broaches the soft guide resulting in a sloppy fit.

If I encounter any resistance at all it is time to use a stone on the side of the stem tip to relieve the mushroomed area.

Even seen stem tips that were deformed to the point where the keeper groove had collapsed and pinched the keeper clip. One clip had cracked in two.



Last edited by Jesse Open; 12-15-2021 at 06:52 AM.
Old 12-15-2021, 06:51 AM
  #51670  
Glowgeek
 
Join Date: Feb 2016
Posts: 3,617
Received 65 Likes on 65 Posts
Default

Great tips for disassembly Gary. Words to live by.
Old 12-15-2021, 09:59 AM
  #51671  
706jim
 
Join Date: Mar 2007
Location: Thunder Bay, ON, CANADA
Posts: 136
Received 6 Likes on 6 Posts
Default

Since Saito cylinders don't have a removable head are the valve guides parallel to the cylinder bore? I own two Saitos but have not disassembled them to check.
Otherwise, I have no idea how they would machine the valve seats.
Old 12-15-2021, 10:07 AM
  #51672  
Glowgeek
 
Join Date: Feb 2016
Posts: 3,617
Received 65 Likes on 65 Posts
Default

Originally Posted by 706jim
Since Saito cylinders don't have a removable head are the valve guides parallel to the cylinder bore? I own two Saitos but have not disassembled them to check.
Otherwise, I have no idea how they would machine the valve seats.
The valves are canted and the combustion chamber is hemispherical. Valve location leaves just enough room for tooling in the cylinder for cutting the seats.
Old 12-15-2021, 04:32 PM
  #51673  
Jesse Open
 
Jesse Open's Avatar
 
Join Date: Mar 2018
Location: 30 Miles North of Canada Border
Posts: 3,788
Received 92 Likes on 84 Posts
Default

Often the spring retainers are just a bit sticky going over the valve tip. Good clue that you should de-burr the sides.

The HC FA-65 I took in last week was the worst I had seen so far. The owner had heated the rocker pivots with a torch to remove the pins. In so doing, he had destroyed the springs. The C Clip keeper on one was cracked in two, both were very tight in the grooves. The new clips would not fit the keeper groove at all.

New valves, springs, retainers, keepers and re-finished tappets. Along with a ring and bearings. The spare parts box took quite a hit on this engine!

Ready for it's next plane.
Old 12-15-2021, 04:46 PM
  #51674  
Jesse Open
 
Jesse Open's Avatar
 
Join Date: Mar 2018
Location: 30 Miles North of Canada Border
Posts: 3,788
Received 92 Likes on 84 Posts
Default

Originally Posted by the Wasp
Gary, go back and look at the Pics, it is imposable to get that seat width consistent with only a valve to work with. even Saito with all their tooling didn't get it correct. and to add, as I said nothing is at a 90 degree so the valve face is not level to the celling. not my fault. it all shows it in the pics.

Jim
Sorry Jim, I just now saw this.
I was hoping you would be able to make a tool similar to what we discussed. Actually it would take two , one for the throat and one for the topside.

Hope I didn't sound negative!
What you have done looks great, getting that seat narrowed and constant would be a big improvement. Maybe Dave could turn a couple of cutters (?) I would be glad to give tips on making them should be very basic.

Yes, the makers do get pretty sloppy in this area!




Old 12-16-2021, 07:38 AM
  #51675  
Jesse Open
 
Jesse Open's Avatar
 
Join Date: Mar 2018
Location: 30 Miles North of Canada Border
Posts: 3,788
Received 92 Likes on 84 Posts
Default

Originally Posted by 1200SportsterRider
I was about to order an RMJ ring for the 150, there is a choice of ring thicknesses, so I have to measure the ring. https://rmjmachineworx.com/online-st...s/saito-fa-150

The choices, .039" and .0585", I checked and the 300 offers the same choice.

Dave,

Just happened to recall that Sr, Telemaster had some cylinders and pistons that were pulls from brand new engines. I think they were for the 150. He was willing to sell them. Maybe still has them (?)


FYI

RE ring thicknesses:

The .039" ring is 1 millimeter thick.
The .0585" ring is a 1.5 millimeter
thickness.


Last edited by Jesse Open; 12-16-2021 at 09:00 PM.

Thread Tools
Search this Thread

Contact Us - Manage Preferences - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service -

Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.