Cheap Dobsons sometimes need a diet

[PeterHA]

My 12" Bintel starts to deteriorate in the mount.
It was always too flexible for my taste and the stiffening, original EbonyStar and virgin Teflon helped but now humidity starts creeping in.

So I decided on a diet leading to a stiffer and 60% lighter mount.
From Alexander I purchased a new EbonyStar disc (due next week) and this weekend I played with 45$ worth of ply.

I will post later the base which is only 300 grams, the woodwork runs just below 6.5 kg.

[mental4astro]

Nice work there, Peter, :)

Are you going to just use varnish (I love the look of timber - but that's me...), or are you going to paint/stain the mount before some varnish?

[PeterHA]

Alexander,

Good Question.
I have not decided yet. I am tossing between a Jarra oil based stain and thereafter 3 coats of water based Polyurethane or just the 3 coats of Polyurethane.
Will decide within the next 2 days ;)

[PeterHA]

Here some pictures of the result of $70 of ply, harware, clear polyurethane and last two weeks spare time:

7 kg down from 15 kg of the old base
Smaller 50x43 cm from 65 cm
All ply with 4 coats of clear waterbased Polyurethane
Integrated encoders for ArgoNavis
Hight adjustable Argo stalk
Cable management, no loose ends
Stiffer than original
Azimut with Teflon on EbonyStar (thanks to Alexander of this forum)
Very light base with Teflon pad on top of feet (Altitude with Teflon on original Bintel scope attachements
Sever small things still to come:

Feet will get plastic (PE) baseplates
Altitude encoder will stay on the mount with a brush guard (aluminium brace) and tool free engagement with the scope
Altitude will get a adjstable felt pad break feature
StarTest at next possible opportunity.

[PeterHA]

Two more images.

[mental4astro]

Blooming gorgeous, mate! :D :thumbsup:

I like the way you've attached the stalk too - simplicity in design. Beautiful.

Taken it for a spin yet? Proof of the pudding is in the eating, though here its out in the field.

[sn1987a]

That's a really good job there Peter, well done.


cheers
Barry

[ZeroID]

Nice work for sure. Excellent stuff.

[gary]

Hi Peter,

Thanks for the email and drawing this to my attention and thanks
for sharing this here on IceInSpace.

Thoughtfully & beautifully executed!

Love your Argo Navis stalk. :)

Interested to hear how it performs under the stars. Congratulations on
a wonderful job.

Best Regards

Gary Kopff
Managing Director
Wildcard Innovations Pty. Ltd.
20 Kilmory Place, Mount Kuring-Gai
NSW. 2080. Australia
Phone +61-2-9457-9049
Fax +61-2-9457-9593
wildcard@wildcard-innovations.com.au
http://www.wildcard-innovations.com.au

[PeterHA]

OK - we had clear sky tonight and I had time to try it out:


Took some time to get the Argo settings adjusted, had it still on a European city, wrong time zone, wrong Fix alt rev, wrong encoder direction...eagerly waiting for the new Argo firmware which should allow several mounts to be set up!!!
Movements are fine up to 250x I have tested it
Will change the Telrad versus a Quickfinder (have a spare) as that is the ideal balance
Argo stalk is a treat

So in total I am happy with the result, clear sky here we come.

[PeterHA]

Hi,

I have now installed two updates.


A brush guard which is dimensioned in a way that I can leave the altitude encoder mounted and if I drop in the OTA I can engage the encoder with a knurled knob. The brush guard protects the encoder from bumps.
An eyepiece rack with 3 positions. I find it very annoying to not be able to change EP with one hand whilst I am on the scope. This rack allows me to have two EPs and a empty position. With the Twist lock EP holder I have, I can now change with one hand and hold the scope with the other. The rack swivels around the Argo stalk, is made of Polycarbonate so it does not scratch the EPs.