Laser Engines - Technical questions

[Denis Watkins]

Posted by TartanMac on 27/04/2018 14:06:25:

I was just wondering if I were to buy the 1.55 glow engine or maybe that pumped glow version you mentioned a while back. Would it be possible to convert the engine to the petrol version later on and if so would it cost a lot to do so ?

Rather than force petrol through the wrong compression ratio, in the wrong combustion chamber, a have to buy new new carb

Why not buy a petrol motor Tartan, they are cheaper

[Jon H]

Posted by TartanMac on 27/04/2018 14:06:25:

I was just wondering if I were to buy the 1.55 glow engine or maybe that pumped glow version you mentioned a while back. Would it be possible to convert the engine to the petrol version later on and if so would it cost a lot to do so ?

in principal you could, but as the pumped glow is not really something we are intending to sell at the moment you might not be able to buy the base engine for your plan. Also, even if you did you would still need a new carb, crankshaft, prop driver, driver collet and front housing as well as all the cdi unit parts.

If you bought the standard glow you would also need a new pinion drive, backplate, pump and regulator on top of the parts listed above. long story short, its not cost effective.

To touch on Denis's comment the comp ratio and other aspects of the combustion chamber are unchanged from the glow engine (dont ask me the number, i cant remember) as we have not had any trouble with knocking through all of our testing. This is likely due to our engines having reasonably conservative c/r in the first place and the design of our combustion chamber is resistant to knock even when running on glow. Thats why we dont supply a locknut as its simply not needed.

Edited By Jon - Laser Engines on 27/04/2018 16:34:09

[David Ovenden]

Can Jon, or anyone else, give me dimensions of the Laser 200V twin engine. Better still, where I can download a dimensioned drawing of the latest model 200V?

[Terry Walters]

This might help David. Try http://www.modelflying.co.uk/albums/member_album.asp?a=39698

[Terry Walters]

This is where I found it.

**LINK**

[Terry Walters]

Or I could measure mine if you let me know the critical dimensions for you.

[Jon H]

Nice one Terry. I don't have a proper dimension drawing yet. its another thing on my list of things to do

[David Ovenden]

Posted by Terry Walters on 16/05/2018 19:50:16:

Or I could measure mine if you let me know the critical dimensions for you.

Terry thanks for the info you sent me. Nice engine but not sure it will fit the model without a lot of mods.

[john stones 1 - Moderator]

Posted by Terry Walters on 16/05/2018 19:50:16:

Or I could measure mine if you let me know the critical dimensions for you.

You flying with the Doncaster flying club Terry ?

[John Stainforth]

David,

I have a Rhino 3D model of the Laser 200V, which I used for my Supermarine S6b model. The representation of the cylinder heads is crude, but the basic dimensions are correct. I could label any dimensions you want. I can also export this from Rhino in various other formats, e.g. Autocad, if that would be of any use to you.

[Jon H]

Nice John. I wish i had fancy 3d tools

[trebor]

Another one landed, it looks like a 70 not too sure without taking it apart. I was told this one only ran the once but I am not so sure due to the sealant on the flanges. What do you think ?

Oppps, helps if I load the pictures 

Edited By trebor on 22/05/2018 17:32:12

[Manish Chandrayan]

The first laser (a 150) I bought came from factory with sealant traces visible. So guess that he normal. My all other Lasers were acquired NIB but from others

Edited By Manish Chandrayan on 22/05/2018 17:38:49

[trebor]

Thanks, I know the joints normally dont have gaskets and I rebuilt a couple without any sealant.

[Jon H]

Its 70, assembled by my own fair hand no less. Dont worry about the sealant as that is standard as we use it in place of a paper gasket.

[Chris Walby]

Why do you need to take it apart to find the size, the 70 and 80 are quite different and the sizes are on the Laser Web site .

Plus the prop nuts are different sizes between 70 and 80's, best send it to me and I'll check it out in my BH Speed Air (goes like the clappers with a 70... but with an 80....ooorrr

[trebor]

Posted by Jon - Laser Engines on 22/05/2018 17:50:19:

Its 70, assembled by my own fair hand no less. Dont worry about the sealant as that is standard as we use it in place of a paper gasket.

Maybe I should have sealed the other I have ? I might be in touch for some more piston rings for my older 70 as this one has more compression. Do you have a piston ring gap size ?

[Manish Chandrayan]

I have to say this. The current setup on Laser website does not allow you to check back on dimensions or anything else for the multiple cylinder engines. Not very encouraging for a commercial enterprise.
I understand that engines are currently not in stock, that's ok. But why on Earth can't one see the engine specs? Why shut that section off?

[Jon H]

Posted by Manish Chandrayan on 22/05/2018 18:37:15:
I have to say this. The current setup on Laser website does not allow you to check back on dimensions or anything else for the multiple cylinder engines. Not very encouraging for a commercial enterprise.
I understand that engines are currently not in stock, that's ok. But why on Earth can't one see the engine specs? Why shut that section off?

Because my time is limited and telling people individually that an item is out of production is not especially efficient. As the availability notices detail we have been closed for the past 2 months while we moved our factory. Certain engines have been removed from production as i simply did not have the resources to continue working on the entire range. I had to scale things back to stand a chance of finishing anything. Given that the engines were out of production I did not see it a problem to remove the product pages as those products don't exist at that exact moment and so information promoting their sale was not really required. A number of people emailed me asking about availability/dimension drawings and after I explained the situation I emailed them dimensions and information directly where possible.

I also do not have the option to mark items as out of production on the website. The software our website is built on is not easy to use and I have far better things to do than faff with it for hours on end trying to beat it into submission. I came up with the most efficient solution I could given what I have to work with.

Trebor, since early last year we have had a new specification of piston ring which offers better performance. The issue is not so much the gap size (which we keep as small as we can) but with the tension in the ring. This is important as it keeps the ring held against the cylinder wall. Give me a call tomorrow if you need more information about it.

[Manish Chandrayan]

Jon
I do not agree to large part of what you have reasoned. To illustrate,
Just because the engine is not in stock does not mean it's no longer there. There are plenty of examples in use or being traded by modeller, who may have a need to look up some critical dimensions. Case in point being a post preceeding few posts where some one wanted to know dimensions and I had to look up Gordon's album as I was about to acquire a 200V.
The other example, You have been nice to people emailing them dimensions and other details. But you have been telling us how pressed for time you have been. Will it not save some of your time if the ordinarily asked information was available on website?.

[John Stainforth]

Perhaps, Jon, you don't want people to realise that the length of the Laser 200V, from firewall to prop-driver, is exactly the same as a bunch of competing OS engines mounted on an OS radial mount!

[bert baker]

Posted by John Stainforth on 23/05/2018 08:09:27:

Perhaps, Jon, you don't want people to realise that the length of the Laser 200V, from firewall to prop-driver, is exactly the same as a bunch of competing OS engines mounted on an OS radial mo

Really,,

You don't think it's more to do with what folks want to purchase,,

[Jon H]

Posted by Manish Chandrayan on 23/05/2018 03:03:54:
Jon
I do not agree to large part of what you have reasoned. To illustrate,
Just because the engine is not in stock does not mean it's no longer there. There are plenty of examples in use or being traded by modeller, who may have a need to look up some critical dimensions. Case in point being a post preceeding few posts where some one wanted to know dimensions and I had to look up Gordon's album as I was about to acquire a 200V.
The other example, You have been nice to people emailing them dimensions and other details. But you have been telling us how pressed for time you have been. Will it not save some of your time if the ordinarily asked information was available on website?.

The V engines are not out of stock, they are out of production until further notice. These are very different things.

In the case of the 200v i dont even have a dimension drawing for that as i have not had time to create one so in that case the page would not have helped you anyway.

While i understand that you are trying to offer constructive criticism you are not aware of all of the issues i am trying to balance. As such it is not really fair to tell me how to do my job.

John, are they? i have to say i hadnt noticed!

[Manish Chandrayan]

Thank you for taking that as a constructive criticism. I have no intention to tell you or for that matter any one else how to run the shop

[Jon H]

Posted by Manish Chandrayan on 23/05/2018 10:08:06:

Thank you for taking that as a constructive criticism. I have no intention to tell you or for that matter any one else how to run the shop

I appreciate this, thanks.

By the way if anyone wants an engine now is the time. Single cylinder engines are in stock but im already out of 100's. Im also away on holiday from friday (i know, worst timing ever) so we will be closed again until June 11th.