New Project - Fixed Height Wooden Tripod

[AdeKing]

I'm looking for a new project and having just completed renovating a couple of old wooden tripods, lusting after a Berlebach Planet, and reading DIY tripod threads on SGL, I have come to the decision that I would like to have a go at making my own.

I am in possession of a Berlebach Planet top plate and also a Uni 18 top plate and would like to build fixed leg tripods around these parts.

I have read the excellent threads by @Fozzie on his fixed leg tripod builds and one from @Moonshane on the same topic, as well as a couple of threads on CN, where DIY tripods seem to be rather popular.

This post by @Rusted appeared in the second of the @Fozzie threads

and was illustrated by these images from from @Peter Drew.

So, I thought that rather than trying to make a copy of a Berlebach Planet but with fixed legs, that I quite liked the idea of following the inverted isosceles triangle leg design.  I'm hoping that this will produce a nice stable tripod but will help to keep the weight down.

This is the Planet top plate that I have.  It will need a mod to allow a Vixen GP to be attached, but as I also have an iOptron AZ Pro and Pier Extension it could be used for that setup instead.

The Berlebach Planet top plate that the tripod will be built around has a 100mm spacing between the side struts of the legs and these will obviously come together and join in a much narrower foot.

Key aims are:

1) I want the tripod to provide a stable support for a Vixen GP holding an Altair Astro 102 f/11 Achro.  The other setups I have hold my other OTAs nicely, but the length of the f/11 makes it more tricky to mount without getting quite a bit of vibration and quivering when focusing and this is what I want the tripod to eliminate.

2) I want to use wood as I love wooden tripods

3) I would like some degree of adjustment via adjustable feet to correct for slightly uneven ground, but don't want the complexity of making up fully adjustable legs with a sliding central section.  I was thinking of articulated machine feet like this into a threaded insert: 

But as I'm after a really solid setup I do quite like the idea of just having spikes on the end of the legs with rubber covers that can be added like those that Fozzie used, though this would obviously remove any chance of small height adjustment and require me to select fairly level ground to set up on.  

4) I'm a novice woodworker and am no engineer so would like to keep the design as simple as possible.

However, I'm after suggestions and opinions on a few things:

a) what would be the best wood type to use.  I know that Berlebach and Oberwerk tripods are manufactured from Ash and that Ash seems to be generally accepted as being well suited to use in astronomy and photography wooden tripods.  But in reading various threads on SGL and CN I have seen a lot of different suggestions including Oak, American Ash, European Ash, Beech, Sapele and Iroko.  Apart from selecting a hardwood, are there any gotchas inherent in selecting the wood type?  The tripod will obviously be used in damp and dewy conditions, but will not be left outside for extended periods, thats what my pillar mount is for.

b)  I'm Intending to finish the wood with Teak Oil to seal the wood and bring out the grain, unless there are other suggestions.  I've assumed that a varnish finish would be likely to bind to the tripod top when the tops of the legs are tightened up and so will be avoiding varnish. 

c) Do I need to give special consideration to the holes at the tops of the legs where I'm intending that an M8 coach bolt will be employed as the pivot point with an adjustable clamping handle and washer as used on the Uni 18 and Planet tripods.  Should I drill oversize holes and use a metal sleeve in there, though I'm guessing that the shrinkage of the wood might pose a problem here.

d) How thick should the side struts of each leg be?

e) I want to use one of the Berlebach spread stoppers as I find a spread stopper makes setting up a tripod less of a wrestling match than when you have three independent legs each of which is trying to do its own thing, so I will obviously need a brace or infilled section of the leg to attach the spread stopper to.  But how wide should I am for the spread of the feet to be?  This will control where along the length of the leg the spread stopper is fitted with the higher is is fitted making he spread of the feet wider.

f) This may be a silly question, but will the side struts need any cross bracing along their length? (apart from where the spread stopper needs to be attached.

This is all I can think of at the moment, but I have quite possibly not considered a lot of things.

I'm expecting this to be a long running project as I'll be learning my craft as I go, so am not in a particular hurry but intend to update this thread as I go.

Thanks for any help in advance.

Ade

  

[Fozzie]

Good man, I love a good tripod build Thread.. 

from your description, i think your talking along the line of this kind of tripod

I think these look great, a very classic elegant design.. This is a IR Poyser telescope & stand, its a "furniture level scope" that you mind being around the house, or that your other half doesn't mind being around the house!

The legs here look set to an angle, with the infilling also mirroring that angle, which gives you fixing points for your BB spreader.  TBH honest i'm not sure how that would work at the hinge, they look to be fixed of set to the plane of the bolt running through the hinge, as opposed to running square and flexing the legs to an angle.

Wood wise, always worth a conversation the supplier you have in mind..  I've used sapele and iroko, TBH the iroko has a nasty habit of splintering due to little calcium deposits, if you catch one with saw or drill bit/router it blows, i had to do some filling on mine to cover, which now stands out somewhat after the wood has darkened to a deep red.

I would think, Oak, Ash, Beech are all good options.. TBH i like this bit the most, which wood to use as opposed to actually doing the work as I hate doing DIY and I've no real woodworking skills so i find it stressful... plan once, twice, check it three times then cut and hope for the best!..

what about Maple or Idigbo all of these should stay fairly pale.. the sapele and Iroko i used have all gone a deeper red colour over the last year.. 

As it's not my money i think Cherry would be lovely.

Oil wise, teak is a winner for lots of occasions, but OSMO do a range of UV protect oil for exterior wood I've used that, bit expensive but a little goes a long way. 

Looking forward to seeing how you get on.

Ta

Fozzie

[CraigT82]

Sounds like a nice project Ade! I've got some spiked feet you can have if you want them (bought from Berlebach). I don't have the rubber covers but I think you can buy these separately? Anyway let me know if they can be of use and I'll send them on.

[AdeKing]

12 hours ago, Fozzie said:

Good man, I love a good tripod build Thread.. 

from your description, i think your talking along the line of this kind of tripod

I think these look great, a very classic elegant design.. This is a IR Poyser telescope & stand, its a "furniture level scope" that you mind being around the house, or that your other half doesn't mind being around the house!

The legs here look set to an angle, with the infilling also mirroring that angle, which gives you fixing points for your BB spreader. 

Wood wise, always worth a conversation the supplier you have in mind..  I've used sapele and iroko, TBH the iroko has a nasty habit of splintering due to little calcium deposits, if you catch one with saw or drill bit/router it blows, i had to do some filling on mine to cover, which now stands out somewhat after the wood has darkened to a deep red.

I would think, Oak, Ash, Beech are all good options.. TBH i like this bit the most, which wood to use as opposed to actually doing the work as I hate doing DIY and I've no real woodworking skills so i find it stressful... plan once, twice, check it three times then cut and hope for the best!..

what about Maple or Idigbo all of these should stay fairly pale.. the sapele and Iroko i used have all gone a deeper red colour over the last year.. 

As it's not my money i think Cherry would be lovely.

Oil wise, teak is a winner for lots of occasions, but OSMO do a range of UV protect oil for exterior wood I've used that, bit expensive but a little goes a long way. 

Looking forward to seeing how you get on.

Ta

Fozzie

Hi Fozzie,

Thanks for the comments.  Yes this is exactly what I'm thinking, though it looks very different in wood than it does in Peter Drews aluminium stock.

With the infilling, the design of the legs is more along the lines of your first tripod build, though with triangular rather than parallel sided legs.

With regards to the wood type, I'm thinking probably European Ash, though may have fun doing some window shopping.

Cherry Wood is lovely, but as you say it comes at a premium.

12 hours ago, Fozzie said:

TBH honest i'm not sure how that would work at the hinge, they look to be fixed of set to the plane of the bolt running through the hinge, as opposed to running square and flexing the legs to an angle.

 I have been thinking exactly this since I decided on this design last night, maybe it will need some wooden wedges fitting to the inside of the side struts to that the struts are held at the correct angle, rather than bending them, but where they attach to the pivot point they still sit flat against the top plate if that makes sense.  Although, this will still give me issues with the bolt as the side struts of the legs will still be at an angle relative to the flat ends of the coach bolt.

Hmmm, so careful thinking is obviously in order.

11 hours ago, CraigT82 said:

Sounds like a nice project Ade! I've got some spiked feet you can have if you want them (bought from Berlebach). I don't have the rubber covers but I think you can buy these separately? Anyway let me know if they can be of use and I'll send them on.

Thanks for the comments and offer Craig, this is what I have changed my mind to consider as today I have had a play with my Uni 18, which is fitted with a set of these, and I realised how much they add to the stability of the setup.

I realised afterwards that a perfectly level tripod top makes very little difference with an EQ mount to a visual only astronomer such as myself.  The iOptron pillar extension has levelling screws on the top plate which work with the AZ Pro that I have so no difference there either, so the spiked feet are all go.

I'll send you a PM before we get our wrists slapped for discussing this on the open forum.

[Fozzie]

15 hours ago, AdeKing said:

 I have been thinking exactly this since I decided on this design last night, maybe it will need some wooden wedges fitting to the inside of the side struts to that the struts are held at the correct angle, rather than bending them, but where they attach to the pivot point they still sit flat against the top plate if that makes sense.  Although, this will still give me issues with the bolt as the side struts of the legs will still be at an angle relative to the flat ends of the coach bolt.

Hmmm, so careful thinking is obviously in order.

that's not a bad idea, and the bolts on the outside are not an issue, you can just countersink the wood in the same plan as the as the bolt so it sits flush.  Obviously the counter sunk would be deeper at the top than the bottom to square it off, I doubt it would be objectionable..

I just wonder if you could flex the wood enough to form the shape without putting too much stress on it..  if you started with parallel legs, so everything was square at the hinge, add a brace point here, that's square, then pinch the two sections together, i wonder over say 1200mm (or what ever the height of the remaining leg is) would you (the wood) have enough natural flex to for the shape you needed, you'd then just need to profile you tapered infills, and fix together. 

could be worth a go or a test run..   

[Peter Drew]

This is the way I used for fixed height wood tripods. (last paragraph)  Works well.     🙂

Edited July 17, 2020 by Peter Drew
addition

[CraigT82]

Steam bending would give the best results and Ash is great for this. It would result in the least amount of residual stress in the legs.  There's lots of video on YouTube about DIY steam bending. 

May not be the ideal solution though if you don't have any of the kit to hand. If the bend at the end of the legs isn't too steep then you could probably do it using a jig and clamps (no steam) and just bending it bit by bit leaving a few days for the wood fibres to stretch between bends. 

Making a laminated leg may also be an option and would allow easy bending. Could alternate the grain between strips for maximum strength. 

Edited July 17, 2020 by CraigT82

[Fozzie]

38 minutes ago, CraigT82 said:

Steam bending would give the best results and Ash is great for this. It would result in the least amount of residual stress in the legs.  There's lots of video on YouTube about DIY steam bending. 

May not be the ideal solution though if you don't have any of the kit to hand. If the bend at the end of the legs isn't too steep then you could probably do it using a jig and clamps (no steam) and just bending it bit by bit leaving a few days for the wood fibres to stretch between bends. 

or beech...  Bending slowly over time sounds like the ticket to me, you could easily make a jig up using wing nut bolts, then give as little of a turn as you wanted to slowly stretch the wood in to shape..

Had another thought finishing wise, Osmo Polyix Oil.. is a hard wax oil hybrid, takes up to a couple of weeks to set hard, but it's dry within a few hours..  After it's set, finishing wax, couple of coats.. that will look really nice!  The polyix oil (others are available like Fides hard wax oil) you can get clear or tinted if you want to add a stain as well..  

I stripped back a table a few weeks back and finished with this combo, no idea what wood it is mind, but after i got off the horrible coloured wax/stain the wife used it came up well.. see below, my pine observing chair is also finished with this combo..

[AdeKing]

On 17/07/2020 at 13:20, Fozzie said:

that's not a bad idea, and the bolts on the outside are not an issue, you can just countersink the wood in the same plan as the as the bolt so it sits flush.  Obviously the counter sunk would be deeper at the top than the bottom to square it off, I doubt it would be objectionable..

I just wonder if you could flex the wood enough to form the shape without putting too much stress on it..  if you started with parallel legs, so everything was square at the hinge, add a brace point here, that's square, then pinch the two sections together, i wonder over say 1200mm (or what ever the height of the remaining leg is) would you (the wood) have enough natural flex to for the shape you needed, you'd then just need to profile you tapered infills, and fix together. 

could be worth a go or a test run..   

I've been doing some research over on CN and from the search results, opinions and ideas I've seen, it appears that building your own wooden tripod is a much bigger thing stateside than it is on this side of the pond.

It appears that I was on the right track with my post about wedges, and it seems that countersinking is not required, based on this post.

https://www.cloudynights.com/topic/308494-making-wooden-tripod-question/page-2#entry3962810

I've not yet made a scaled drawing of what I want to achieve, but I don't know why I didn't see this before, but the wedges that will need to be cut from the bottom of the legs to form the feet will have the correct angles to be stuck to the inside of the struts and therefore give a flat mating surface at the hinge, the outside corner of the strut is then squared off, job done and no need for countersinking or bending.

This then gives a straight length of wood with a slight kink at the top end.  Simples.

The designs I've seen have the bottom of the legs bolted together, which does pose a bit of a problem with putting in a threaded insert, but I'll work on that in a bit.

That way I don't need to worry about having to bend the wood in jigs or anything like that.  I like simple.

On 17/07/2020 at 13:39, Peter Drew said:

This is the way I used for fixed height wood tripods. (last paragraph)  Works well.     🙂

Thanks Peter, it's good to know that the parallel sides and flexing method works for when my "wood butchering" skills (thanks for the phrase @Alan White) inevitably kick in and the realisation of what I think I can do and what I can actually achieve materialises.

On 17/07/2020 at 13:40, CraigT82 said:

Steam bending would give the best results and Ash is great for this. It would result in the least amount of residual stress in the legs.  There's lots of video on YouTube about DIY steam bending. 

May not be the ideal solution though if you don't have any of the kit to hand. If the bend at the end of the legs isn't too steep then you could probably do it using a jig and clamps (no steam) and just bending it bit by bit leaving a few days for the wood fibres to stretch between bends. 

Making a laminated leg may also be an option and would allow easy bending. Could alternate the grain between strips for maximum strength. 

Thanks Craig, I'm hoping I have a solution that won't involve steam bending.  I watched an interesting youtube video by a Guy in Australia (I think) and saw how many times he failed trying to do this, though to be fair he was going for a 90 degree curve, whereas the bend I would need might be only 2-3 degrees.

On 17/07/2020 at 14:26, Fozzie said:

or beech...  Bending slowly over time sounds like the ticket to me, you could easily make a jig up using wing nut bolts, then give as little of a turn as you wanted to slowly stretch the wood in to shape..

Had another thought finishing wise, Osmo Polyix Oil.. is a hard wax oil hybrid, takes up to a couple of weeks to set hard, but it's dry within a few hours..  After it's set, finishing wax, couple of coats.. that will look really nice!  The polyix oil (others are available like Fides hard wax oil) you can get clear or tinted if you want to add a stain as well..  

I stripped back a table a few weeks back and finished with this combo, no idea what wood it is mind, but after i got off the horrible coloured wax/stain the wife used it came up well.. see below, my pine observing chair is also finished with this combo..

Thanks for the suggestions on finishes, I'm enjoying looking at what wood to use as I'd like it to look pretty as well as being stable and vibration damping, though at the moment I'm veering towards going with the herd and thinking that Ash is probably what I'll end up with.

That is a lovely finish you've achieved on that table, I love it.