help wanted please - dh98

[richard armstrong]

hi all

just a quick request for a little help,

i been given 2 26cc petrol motors, (yippee), i would like to have a go at building a twin dh98 mossie, but i am not sure how to calculate the wind span size for the engines, my plan is to build under the 20kg rules all wood construct, hopfully to have one of the lma members test fly it???? (to many projects not enough time)

also i am having a hard time finding scale plans, either at a lower scale to enlarge and mod, or the right size can any one point me in the right direction, please

all the best

[robbieskipton]

Hi,
ahh a lovely Mosquito

Well, the first question i will ask is are you going to draw it your self in cad and get it cut?

I have a 3 view if thats any help to you....Im designing one myself at the moment for someone.. for 2 x 24 zenoah engines..

I worked out the wing span at 110inch which is 16% scale.. weight approx 33lbs

[Phil Clark]

Brian Taylor (Plans now available via Traplet Publications) does 2 Mosquito plans.....the largest of which if I remember is 81" span.

https://shop.traplet.com/product.aspx?c=2516

For a pair of 26's....I'd be looking at somethng between 100 and 110" span.......so a 25 - 30% enlargement will do just fine. At this level of enlargement, other than altering some timber choices and a few sizes, you should be able to build it petty much as per plan and definately keep it under the 20kg's

Phil

[Ken Bones]

Agree with you there Phil, My 1/6 Tigercat , 102'', 28lbs flew ok on Z23s. Now being reworked i expect the AUW to be around 32lb and power this time will be Z26s.
Ken B.

[richard armstrong]

Hi,
ahh a lovely Mosquito

Well, the first question i will ask is are you going to draw it your self in cad and get it cut?

I have a 3 view if thats any help to you....Im designing one myself at the moment for someone.. for 2 x 24 zenoah engines..

I worked out the wing span at 110inch which is 16% scale.. weight approx 33lbs

please send any'all drawings that might help

i would love draw it up myself (advice on former's, necells etc), then lazer cut to save time, but i have never done that not sure where to start any advice would be great?? prefer to work off cad files as i can print sections at a time also ideal for making alterations

110/120" (16 to 20%)is ideal for carting about to shows, i can design it to break down into 4 to 5 sections

i have a 1/4 scale raf chippe on the bench for a 45cc, to finish

Brian Taylor (Plans now available via Traplet Publications) does 2 Mosquito plans.....the largest of which if I remember is 81" span.

https://shop.traplet.com/product.aspx?c=2516

For a pair of 26's....I'd be looking at somethng between 100 and 110" span.......so a 25 - 30% enlargement will do just fine. At this level of enlargement, other than altering some timber choices and a few sizes, you should be able to build it petty much as per plan and definately keep it under the 20kg's

Phil

thanks phil i will take a look, how do i get them enlarge our local print shop don't have the gear to enlarge??

ken b great would love to see pics

[Phil Clark]

Richard

You need to find a print shop that can first of all scan them, then enlarge, then print.

DON'T just get the enlarged on a photocopier.......the large 'roller' type copiers are well know to 'stretch' drawings. Over a 2m long plan, you'll get an inaccuracy of a good 'cm' or more meaning fuselages and wing spans get stretched out of proportion. If they are scanned 1st, the enlargement can be carried out much more accurately before printing. This method is a little more expensive, but you'll get a better plan out the other end.

My local 'Prontaprint' has the facility to do this, so maybe look for your nearest branch? (or search the Yellow Pages and ring round all the local copy centres until you find one that can)

Phil

[richard armstrong]

Richard

You need to find a print shop that can first of all scan them, then enlarge, then print.

DON'T just get the enlarged on a photocopier.......the large 'roller' type copiers are well know to 'stretch' drawings. Over a 2m long plan, you'll get an inaccuracy of a good 'cm' or more meaning fuselages and wing spans get stretched out of proportion. If they are scanned 1st, the enlargement can be carried out much more accurately before printing. This method is a little more expensive, but you'll get a better plan out the other end.

My local 'Prontaprint' has the facility to do this, so maybe look for your nearest branch? (or search the Yellow Pages and ring round all the local copy centres until you find one that can)

Phil

thanks for that

[Pat Cuss]

Also only scan and print one wing half, then get them to mirror image and print again, you then carefully sellotape the wings drawing together at the centre thus giving you a really accurate drawing. Do the same with the plan view of the fuz and re-tape together down the cuntre line. Tailplane as well. You would be surprised how far out some hand drawn plans can be.

[richard armstrong]

Also only scan and print one wing half, then get them to mirror image and print again, you then carefully sellotape the wings drawing together at the centre thus giving you a really accurate drawing. Do the same with the plan view of the fuz and re-tape together down the cuntre line. Tailplane as well. You would be surprised how far out some hand drawn plans can be.

i know what you are saying and thanks, i took the 1/4 scale raf chippe plans had them scanned, traced them and made lazer sheet for cutting, and a few mods to the under cart,